Reference List

Abe K and Ziemer R (1991), "Effect of tree roots on shallow-seated landslides", USDA Forest Service General Technical Report PSQ-GTR-130. , pp. 11-20.
Abstract: The Technical Session of the Subject Group on Natural Disasters was held on the afternoon of August 7, 1990 as part of the XIX World Congress of the lnlernational Union of Forestry Research Organizations in Montreal, Canada. About 35 scientists representing 10 nations were in attendance. Seventeen papers were presented, addressing the topics of all four Working Pxties in the Group. Two papers reported research on torrents, three were about snow, five concerned landslides, and seven USDA Forest Service Gcn. Tech. Rep. PSW-GTR-130. 1991. discussed watershed management problems. Four of the invited papers can be found in Volume 1 of the Proceedings of Division I , and two are in this volume. The remainder of this volume includes nine of the contributed papers presented at the technical session plus one that was not orally presented. 11 is hoped that this volume, together with others supported by the Subject Group in recent years, will foster increased understanding of natural disasters in forested environments.
Abellan A, Jaboyedoff M, Oppikofer T and Vilaplana JM (2009), "Detection of millimetric deformation using a terrestrial laser scanner: experiment and application to a rockfall event", Natural Hazards and Earth System Sciences. Vol. 9(2), pp. 365-372.
Abstract: Terrestrial laser scanning (TLS) is one of the most promising surveying techniques for rockslope characterization and monitoring. Landslide and rockfall movements can be detected by means of comparison of sequential scans. One of the most pressing challenges of natural hazards is combined temporal and spatial prediction of rockfall. An outdoor experiment was performed to ascertain whether the TLS instrumental error is small enough to enable detection of precursory displacements of millimetric magnitude. This consists of a known displacement of three objects relative to a stable surface. Results show that millimetric changes cannot be detected by the analysis of the unprocessed datasets. Displacement measurement are improved considerably by applying Nearest Neighbour (NN) averaging, which reduces the error (1 sigma) up to a factor of 6. This technique was applied to displacements prior to the April 2007 rockfall event at Castellfollit de la Roca, Spain. The maximum precursory displacement measured was 45 mm, approximately 2.5 times the standard deviation of the model comparison, hampering the distinction between actual displacement and instrumental error using conventional methodologies. Encouragingly, the precursory displacement was clearly detected by applying the NN averaging method. These results show that millimetric displacements prior to failure can be detected using TLS.
Abramson L (2002), "Slope Stability and Stabilization Methods" , pp. 1-25. John Wiley & Sons.
Abstract: The evolution of slope stability analyses in geotechnical engineering has followed closely the developments in soil and rock mechanics as a whole. Slopes either occur naturally or are engineered by humans. Slope stability problems have been faced throughout history when men and women or nature has disrupted the delicate balance of natural soil slopes. Furthermore, the increasing demand for engineered cut and fill slopes on construction projects has only increased the need to understand analytical methods, investigative tools, and stabilization methods to solve slope stability problems. Slope stabilization methods involve specialty construction techniques that must be understood and modeled in realistic ways. An understanding of geology, hydrology, and soil properties is central to applying slope stability principles properly. Analyses must be based upon a model that accurately represents site subsurface conditions, ground behavior, and applied loads. Judgments regarding acceptable risk or safety factors must be made to assess the results of analyses.
The authors have recognized a need for consistent understanding and application of slope stability analyses for construction and remediation projects across the United States and abroad. These analyses are generally carried out at the beginning, and sometimes throughout the life, of projects during planning, design, construction, improvement, rehabilitation, and maintenance. Planners, engineers, geologists, contractors, technicians, and maintenance workers become involved in this process. This book provides the general background information required for slope stability analyses, suitable methods of analysis with and without the use of computers, and examples of common stability problems and stabilization methods for cuts and fills. This body of information encompasses general slope stability concepts, engineering geology principles, groundwater conditions, geologic site explorations, soil and rock testing and interpretation, slope stability concepts, stabilization methods, instrumentation and monitoring, design documents, and construction inspection. Detailed discussions about methods used in slope stability analyses are given, including the ordinary method of slices, simplified Janbu method, simplified Bishop method, Spencer’s method, other limit equilibrium methods, numerical methods, total stress analysis, effective stress analysis, and the use of computer programs to solve problems. This book is intended for individualswhodeal with slope stability problems, including most geotechnical engineers and geologists who have an understanding of geotechnical engineering principles and practice.
Acevo-Herrera R, Aguasca A, Bosch-Lluis X, Camps A, Martinez-Fernandez J, Sanchez-Martin N and Perez-Gutierrez C (2010), "Design and First Results of an UAV-Borne L-Band Radiometer for Multiple Monitoring Purposes", Remote Sensing., July, 2010. Vol. 2(7), pp. 1662-1679.
Abstract: UAV (unmanned Aerial Vehicle) platforms represent a challenging opportunity for the deployment of a number of remote sensors. These vehicles are a cost-effective option in front of manned aerial vehicles (planes and helicopters), are easy to deploy due to the short runways needed, and they allow users to meet the critical requirements of the spatial and temporal resolutions imposed by the instruments. L-band radiometers are an interesting option for obtaining soil moisture maps over local areas with relatively high spatial resolution for precision agriculture, coastal monitoring, estimation of the risk of fires, flood prevention, etc. This paper presents the design of a light-weight, airborne L-band radiometer for deployment in a small UAV, including the hardware and specific software developed for calibration, geo-referencing, and soil moisture retrieval. First results and soil moisture retrievals from different field experiments are presented.
Adams J (1979), "Gravel Size Analysis From Photographs", Journal of the Hydraulics Division-asce. Vol. 105(10), pp. 1247-1255.
Abstract: Gravel sizes measured from photographs of river beds are biased estimates of size when compared to standard sieve analysis. Mean apparent short axis size (for gravel coarser than 8 mm) from photographs may be converted to sieve-equivalent mean size by subtracting 0.1 phi (if mean size in phi units) or multiplying by 1.07 (if mean size in mm). Percentile of the distribution also differ by the same factors. Measures of grain size standard deviation from photographs are approximately equivalent to sieve values. For sizes in phi units the photograph and sieve size frequency distribution curves have similar shape, but are offset by the same bias as the mean size.
AGN (2004), "Permanente Rutschungen, spontane Rutschungen und Hangmuren"
Agung MW, Sassa K, Fukuoka H and Wang GH (2004), "Evolution of Shear-Zone Structure in Undrained Ring-Shear Tests", Landslides., July, 2004. Vol. 1(2), pp. 101-112.
Abstract: Undrained monotonic torque-controlled tests were conducted on fine-grained silica sand to study the shear-deformation process in granular materials by using a ring-shear apparatus. Shear-zone structures at various stages in the undrained shear tests were observed during a series of tests in which the experiments were terminated at different shear displacement. For "undisturbed" samples, the shear zone was only developed during the post-failure stage and its thickness increased with progressed shearing. First the shear surfaces had undulating and asymmetric structures; later they gradually became smooth and parallel to the shearing direction. During this process, pore water pressure was generated, and the effective friction angle decreased correspondingly. Generally, the shear zone could be divided into three parts: the compacted core, the adjacent zone above the core, and the adjacent zone below the core. Grain-size analysis on the sample from the shear zone revealed that grain crushing occurred during each stage and the extent of grain crushing differed for different shear stages. An interesting phenomenon occurred during the steady-state deformation where the coarse and fine particles within the shear zone segregated during motions and a parallel orientation structure developed. These results are helpful for understanding the mechanism of progressive failure in granular material as well as the rapid landslide with long runout study.
Ahnert F (1970), "Functional Relationships Between Denudation, Relief, and Uplift In Large Mid-latitude Drainage Basins", American Journal of Science. Vol. 268(3), pp. 243-263.
Akca D (2013), "Photogrammetric Monitoring of an Artificially Generated Shallow Landslide", Photogrammetric Record., June, 2013. Vol. 28(142), pp. 178-195.
Abstract: An artificial rainfall event was applied to a forested slope in Ruedlingen, northern Switzerland. The experiment triggered a landslide which resulted in mobilising about 130m3 of debris. The event was monitored by a photogrammetric network of four cameras, operating at 5 to 8 frames per second, in order to quantify spatial and temporal changes by tracking tennis balls pegged into the ground. Image measurements were performed using automated image matching methods, implemented through a software package developed in-house. Three-dimensional coordinates of the target points were estimated by running a customised type of bundle adjustment, achieving a positioning precision of +/- 1 center dot 8cm.
Aksoy B and Ercanoglu M (2012), "Landslide identification and classification by object-based image analysis and fuzzy logic: An example from the Azdavay region (Kastamonu, Turkey)", Computers & Geosciences., January, 2012. Vol. 38(1), pp. 87-98.
Abstract: This study presents a data-driven and semiautomatic classification system carried out by object-based image analysis and fuzzy logic in a selected landslide-prone area in the Western Black Sea region of Turkey. In the first stage, a multiresolution segmentation process was performed using Landsat ETM+ satellite images of the study area. The model was established on 5235 image objects obtained by the segmentation process. A total of 70 landslide locations and 10 input parameters including normalized difference vegetation index, slope angle, curvature, brightness, mean band blue, asymmetry, shape index, length/width ratio, gray level co-occurrence matrix, and mean difference to infrared band were considered in the analyses. Membership functions were used to classify the study area by five fuzzy operators such as "and", "or", "mean arithmetic", "mean geometric", and "algebraic product". In order to assess the performances of the so-produced maps, 700 image objects, which were not used in the model, were taken into consideration. Based on the results, the map produced by "fuzzy and" operator performed better than those classified by the other fuzzy operators. The proposed methodology applied in this study may be useful for decision makers, local administrations, and scientists interested in landslides. It may also be useful in landslide-prone areas for planning, management, and regional development purposes. (C) 2011 Elsevier Ltd. All rights reserved.
Aleotti P (2004), "A warning system for rainfall-induced shallow failures", Engineering Geology., June, 2004. Vol. 73(3-4), pp. European Geophys Soc.
Abstract: It is widely recognised that soil slips and debris flows are triggered by short intense storms. Owing its geologic, geomorphologic and climatic settings, the Piedmont Region (NW Italy) is highly prone to the occurrence of this kind of landslides. In the last two centuries, in fact, a total of 105 severe meteoric events which triggered shallow failures occurred and, of these, 18 events took place from 1990 to 2002. A fair number of rainfall thresholds have been proposed in the literature, defined both on empirical or on physical bases. Empirical thresholds are defined collecting rainfall data for landslide meteoric events and for events without landslides, while physical thresholds are based on numerical models that consider the relation between rainfall, pore pressure and slope stability. The main objective of this paper is the identification of the empirical triggering thresholds for the Piedmont Region. Four meteoric events were selected and analysed (November 4-5, 1994; July 7-8, 1996; April 27-30, 2000; October 13-16, 2000) because they supply a wide range of variation for both rainfall parameters (duration, intensity, cumulative rainfalls) and the number of induced landslides. In the intensity-duration plot, the critical limit is described by the equation: I = 19D(-0.50) (where I = rainfall intensity expressed in mm/h and D = rainfall duration expressed in hours). Such a limit is traced to envelop 90% of the points on the graph. In the NI-D diagram the triggering thresholds are given by the equations NI = 0.76D(-0.33) and NI = 4.62D(-0.79) (where NI = normalised intensity with respect to the annual precipitation, MAP, expressed in %, [(mm/h)/PMA] X 100). In the article the different meaning of these thresholds is discussed. Finally, the diagram NI-NCR is proposed; the triggering threshold is given by the expression: NI = -0.09ln[NCR] + 0.54 (where NCR is the normalised cumulative critical rainfall, [mm/PMA] x 100). The application of the triggering thresholds as a fundamental element in a warning system dedicated to the safeguarding of population in landslide-prone areas is discussed. In detail an operating procedure which is presently being verified and tested in the studied area is described. (C) 2004 Elsevier B.V. All rights reserved.
Aleotti P, Baldelli P and Polloni G (1996), "Landsliding and flooding event triggered by heavy rains in the Tanaro basin", In Proc. of the VIII International Congress Interpraevent 1996, Garmisch-Partenkirchen. Garmisch-Partenkirchen Vol. 1, pp. 435-446.
Abstract: A study of the November 1994 rainstorn triggered phenomena was carried out in a test area of the Tanaro basin (Piedmont, NW Italy), in particular with regard to the shallow slope failures. About 3000 soil slips/debris flows were inventoried and the water courses, together with the main bridges, were surveyed. The slope and river dynamics interaction has been examined and the influence of man-made structures (bridges) on solid transport process has been analyzed. Considerations on hazard and risk assessement, together with a susceptibility map, are also presented.
Aleotti P and Chowdhury R (1999), "Landslide hazard assessment: summary review and new perspectives", Bulletin of Engineering Geology and the Environment. Vol. 58(1), pp. 21-44. Springer-Verlag.
Abstract: This paper deals with several aspects of the assessment of hazard and risk of landsliding. In recent years the interest in this topic has increased greatly and there are many technical papers dealing with this subject in the literature. This article presents a summary review and a classification of the main approaches that have been developed world-wide. The first step is the subdivision between qualitative and quantitative methods. The first group is mainly based on the site-specific experience of experts with the susceptibility/hazard determined directly in the field or by combining different index maps. The approaches of the second group are formally more rigorous. It is possible to distinguish between statistical analyses (bivariate or multivariate) and deterministic methods that involve the analysis of specific sites or slopes based on geo-engineering models. Such analyses can be deterministic or probabilistic. Among the quantitative methods discussed is the Neural Networks approach which has only recently been applied to engineering geology problems. Finally several considerations concerning the concept of acceptable risk and risk management are presented.
Alewell C, Meusburger K, Brodbeck M and Banninger D (2008), "Methods to describe and predict soil erosion in mountain regions", Landscape and Urban Planning., December, 2008. Vol. 88(2-4), pp. 46-53. Elsevier Science Bv.
Abstract: Suitable methods to describe and predict soil degradation in mountain areas with low accessibility, steep topography and extreme climate are urgently needed for suitable planning processes in Alpine regions under global change regime. Aerial photograph mapping has been proven to be a valuable tool in surveying landslide development over time. However, landslides< 10 m(2) as well as sheet erosion have been difficult to detect. Thus, the beginning of potentially heavy soil degradation cannot be tracked with aerial photographs. As an early warning system for soil degradation, we analyzed gradients of stable isotopes of carbon and nitrogen from upland (erosion source) to wetland soils (erosion sink). Oxic upland soils and anoxic wetlands differ in their isotopic signature, due to differing isotopic fingerprints of aerobic and anaerobic metabolism in soils. Gradients of delta(15)N and delta(13)C in soils reflected erosion of material. However, if soils were fertilized with manure, the delta(15)N profiles were obscured. To quantify soil erosion, we noted that existing soil erosion models are generally unsuitable for mountain regions. As a first step, we developed a new modelling concept with a special algorithm for spatial discretization with irregular grids. The latter ensures three-dimensional water flow routing that is controlled by topography and not by the underlying algorithm. Regarding quantification of soil erosion an improvement and validation of existing modelling approaches or development of new models is urgently needed. (C) 2008 Elsevier B.V. All rights reserved.
Alkasawneh W, Malkawi AIH, Nusairat JH and Albataineh N (2008), "A comparative study of various commercially available programs in slope stability analysis", Computers and Geotechnics . Vol. 35(3), pp. 428 - 435.
Abstract: The objective of this paper is to study the effect of different slip surface search techniques on the factors of safety obtained using the limit equilibrium (LE) slope stability methods. This objective is accomplished by comparing results from the finite element method, the linear grid method, the rectangular grid method, and the Monte-Carlo searching techniques using different commercially available programs. The results showed that the LE methods are very efficient methods when coupled with a robust searching technique namely the Monte-Carlo method. In addition, the selected slip surface search technique highly influenced the location of the critical slip surfaces as well as the value of the calculated factors of safety.
Altfeld O, Bunza G and Ziegler R (1996), "Eine Karte der Hangdynamik auf der Grundlage geologischer und hydrologischer Ursachen", In Proc. of the VIII International Congress Interpraevent 1996, Garmisch-Partenkirchen. Garmisch-Partenkirchen Vol. 4, pp. 77-90..
Abstract: 1992 wurde am Bayerischen Landesamt für Wasserwirtschaft das Projekt "Integrales Wildbachschutzkonzept" initiiert. Ein Ziel dieses Vorhabens war es, Karten der Hangdynamik als Grundlage für entsprechende Schutz- und Sanierungsmaßnahmen in Wildbacheinzugsgebieten zu entwickeln, insbesondere auch im Hinblick auf die Folgen erhöhter Nutzungsansprüche, des Wald- und Bodensterbens und der Klimaänderung. Im vorliegenden Beitrag wird über die Erstellung einer Karte der Hangdynamik berichtet. GIS-unterstützte kausalanalytische Untersuchungen trugen dazu bei, die Zusammenhänge der systemimmanenten Faktoren, insbesondere zwischen Geologie, Tektonik und Hydrogeologie zu klären.
In der Karte der Hangdynamik wird das geologisch und hydrogeologisch induzierte "Gefahrenpotential" dargestellt und in Form von Labilitätsstufen ausgewiesen. Die Kartendarstellung erlaubt ferner eine Überlagerung mit anderen thematischen Karten, sodaß sie in eine weitergehende interdisziplinäre Analyse miteinbezogen werden kann.
Amacher MC and O'Neill KP (2004), "Assessing soil compaction on Forest Inventory & Analysis phase 3 field plots using a pocket penetrometer", Research Note, RMRS-RP-46WWW, U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins, Colorado.. , pp. 1-7.
Abstract: Soil compaction is an important indicator of soil quality, yet few practical methods are available to quantitatively measure this variable. Although an assessment of the areal extent of soil compaction is included as part of the soil indicator portion of the Forest Inventory & Analysis (FIA) program, no quantitative measurement of the degree of soil compaction is made. We tested a small, lightweight pocket penetrometer that measures soil compression strength as a simple, quantitative measure of the degree of compaction of mineral soils under forested conditions. Soil compression strengths were significantly higher in compacted trails and areas than in adjacent undisturbed locations. In contrast, no significant difference in soil compression strength was found between rutted trails and adjacent undisturbed areas. A protocol is suggested for further pilot testing of this device as part of the soil indicator assessment. The main disadvantage of this device is that many of the compacted soils had compression strengths higher than the maximum measurable value of 4.5 tons/ft2. Despite this limitation, this device can rapidly and easily distinguish between compacted and uncompacted areas in the field. Time previously spent by field crews trying to identify qualitative evidences of compaction can instead be used to provide a quantitative measure of the degree of compaction, which would strengthen the analysis and interpretation of the soil quality indicator.
Ampferer O (1937), "Über die eiszeitlichen Ablagerungen des Laternser Tales", Verhandlungen der Geologischen Bundesanstalt (Wien). Vol. 12, pp. 253-255.
Anderson K and Croft H (2009), "Remote sensing of soil surface properties", Progress In Physical Geography., August, 2009. Vol. 33(4), pp. 457-473.
Abstract: Remote sensing is now in a strong position to provide meaningful spatial data for use in soil science investigations. In the last 10 years, advancements in remote sensing techniques and technologies have given rise to a wealth of exciting new research findings in soil-related disciplines. This paper provides a critical insight into the role played by remote sensing in this field, with a specific focus on soil surface monitoring. Two key soil properties are considered in this review, soil surface roughness and moisture, because these two variables have benefited most from recent cutting-edge advances in remote sensing. Of note is the fact that the major recent advancements in spatial assessment of soil structure have emerged from optical remote sensing, while the soil moisture community has benefited from advancements in microwave systems, justifying the focus of this paper in these specific directions. The paper considers the newest techniques within active, passive, optical and microwave remote sensing and concludes by considering future challenges, multisensor approaches and the issue of scale - which is a key cross-disciplinary research question of relevance to soil scientists and remote sensing scientists alike.
Anderson MG, Richards KS and Kneale PE (1982), "The Role of Stability Analysis In the Interpretation of the Evolution of Threshold Slopes - Reply", Transactions of the Institute of British Geographers. Vol. 7(2), pp. 236-239.
Anderson MG, Richards KS and Kneale PE (1980), "The Role of Stability Analysis In the Interpretation of the Evolution of Threshold Slopes", Transactions of the Institute of British Geographers. Vol. 5(1), pp. 100-112.
Abstract: Stability analyses have been used to interpret the angles of straight slope segments defined as threshold slopes, even where visible evidence of mass movement is lacking. Two problems are identified in interpreting the results of these analyses. First, in the absence of surface expression of mass movement, identification of the threshold slopes is problematical since the systematic variation of slope angle in the drainage basin results in non-threshold slopes being included in a random sample, with occasional fortuitous accord between observed and predicted modal angles. Secondly, there is a wide range of assumptions concerning shear plane morphology, lateral extent of slide, and pore water pressure patterns which can be employed in the calibration of the models. Thus accordance between observed and predicted angles can arise from different model assumptions. These problems are assessed using data on slope form and soil mechanics of some Norfolk dry valleys, and on pore pressures in a motorway embankment subjected to a shallow slide. It is suggested that detailed interpretation of slope evolution using stability analysis and soil mechanical data is limited by the discordance in the levels of sophistication of the theoretical models and the data available for their calibration.
Andrecs P and Hacker R (2005), "Faustformel für die Abschätzung der Volumen von Rutschungen", BFW-Praxisinformation. Vol. 8, pp. 25-26.
Abstract: Angaben über Rutschungsvolumina beruhen meist auf visuellen Schätzungen und sind mit Unsicherheiten verbunden. Vom Institut für Naturgefahren und Waldgrenzregionen des BFW wurde deshalb eine Faustformel zur Volumsbestimmung entwickelt.
Andrecs P, Hagen K, Lang E, Stary U, Gartner K, Herzberger E, Riedel F and Haiden T (2007), "Dokumentation und Analyse der Schadensereignisse 2005 in den Gemeinden Gasen und Haslau (Steiermark)" Wien Vol. 6, pp. 75. Schriftenreihe des Bundesforschungs- und Ausbildungszentrums für Wald, Naturgefahren und Landschaft.
Abstract: Im August 2005 fanden in weiten Teilen Österreichs schwere Unwetter statt, die zu enormen Schäden führten. Das Lebensministerium (BMLFUW) beauftragte daraufhin das BFW mit einer detaillierten Dokumentation der Schadensereignisse in den am stärksten betroffenen Gebieten der Steiermark (Gemeinden Gasen und Haslau bei Birkfeld) und Vorarlbergs. Die Dokumentation der Hochwasserereignisse, Massenbewegungen und Rutschungen erfolgte nach der Methodik des „5W-Standards“, bei der bestimmte Parameter nach festgelegten Standards erhoben werden um damit die Kriterien des Was,Wer,Wo,Wann und Warum von Schadensereignissen näher zu beschreiben. Die im Gelände erhobenen Daten wurden anschließend in das Ereignismeldungsportal des digitalen Wildbach- und Lawinenkatasters eingebracht.
Auswertungen dieser digital erfassten Daten sind ein Schwerpunkt der vorliegenden Arbeit. Dabei wird das Schadensausmaß detailliert dargestellt und die Ursachen und Auslösemechanismen der Schadensprozesse analysiert. Ergänzt werden diese Auswertungen durch Untersuchungen der meteorologischen Rahmenbedingungen, wofür ein neu entwickeltes Analysetool der Zentralanstalt für Meteorologie und Geodynamik eingesetzt wurde. Die Ergebnisse eines für die Geländeerhebungen vom BFW beauftragten Geologen lieferten zusätzlich geotechnische sowie struktur- und hydrogeologische Details. Diese wurden mit am BFW vorhandenen Daten aus Standortskartierungen und Kartierungen der landwirtschaftlichen Böden in Zusammenhang gestellt. Neben diesen Auswertungen werden in der vorliegenden Arbeit auch die im Rahmen des Praxiseinsatzes des Dokumentationsverfahrens gewonnenen Erkenntnisse vorgestellt und die daraus abgeleiteten Vorschläge für eine Weiterentwicklung dieser Methodik präsentiert.
Andrecs P, Markart G, Lang E, Hagen K, Kohl B and Bauer W (2002), "Untersuchung der Rutschungsprozesse vom Mai 1999 im Laternsertal (Vorarlberg)", BFW Berichte. Vol. 127, pp. 55-87.
Angerer H, Hermann S, Kittl H, Poisel R and Roth W (2004), "Monitoring, mechanics and risk assessment of the landslide Lärchberg-Galgenwald (Austria)", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 821-826. Taylor & Francis.
Abstract: The Lärchberg—Galgenwald landslide is situated in the southwestern slope of the Rantenbach valley 2 km upstream of the City of Murau. The slope is built up by marbles some 300 m thick lying on a phyllite base some 140m thick. The cracks of the main scarp, which are some 10m wide, are monitored by wire extensometers and are opening with a precipitation dependent velocity of 30 cm per year. Monitoring by an automatic servo-theodolit revealed that the lowest base area is not yet moving. Numerical analyses showed that an overall volume of up to 10,000,000 m3 might bury the road in the valley and dam up the Rantenbach river causing a debris flow. Measures reducing the amount of precipitation seeping into the ground seem to be most promising due to the high degree of rock fracturing and the dependence of displacements on precipitaion.
Apip, Takara K, Yamashiki Y, Sassa K, Ibrahim AB and Fukuoka H (2010), "A distributed hydrological-geotechnical model using satellite-derived rainfall estimates for shallow landslide prediction system at a catchment scale", Landslides., September, 2010. Vol. 7(3), pp. 237-258.
Abstract: This paper describes the potential applicability of a hydrological-geotechnical modeling system using satellite-based rainfall estimates for a shallow landslide prediction system. The physically based distributed model has been developed by integrating a grid-based distributed kinematic wave rainfall-runoff model with an infinite slope stability approach. The model was forced by the satellite-based near real-time half-hourly CMORPH global rainfall product prepared by NOAA-CPC. The method combines the following two model outputs necessary for identifying where and when shallow landslides may potentially occur in the catchment: (1) the time-invariant spatial distribution of areas susceptible to slope instability map, for which the river catchment is divided into stability classes according to the critical relative soil saturation; this output is designed to portray the effect of quasi-static land surface variables and soil strength properties on slope instability and (2) a produced map linked with spatiotemporally varying hydrologic properties to provide a time-varying estimate of susceptibility to slope movement in response to rainfall. The proposed hydrological model predicts the dynamic of soil saturation in each grid element. The stored water in each grid element is then used for updating the relative soil saturation and analyzing the slope stability. A grid of slope is defined to be unstable when the relative soil saturation becomes higher than the critical level and is the basis for issuing a shallow landslide warning. The method was applied to past landslides in the upper Citarum River catchment (2,310 km(2)), Indonesia; the resulting time-invariant landslide susceptibility map shows good agreement with the spatial patterns of documented historical landslides (1985-2008). Application of the model to two recent shallow landslides shows that the model can successfully predict the effect of rainfall movement and intensity on the spatiotemporal dynamic of hydrological variables that trigger shallow landslides. Several hours before the landslides, the model predicted unstable conditions in some grids over and near the grids at which the actual shallow landslides occurred. Overall, the results demonstrate the potential applicability of the modeling system for shallow landslide disaster predictions and warnings.
Arnold JG, Srinivasan R, Muttiah RS and Williams JR (1998), "Large area hydrologic modeling and assessment - Part 1: Model development", Journal of the American Water Resources Association., February, 1998. Vol. 34(1), pp. 73-89. Amer Water Resources Assoc.
Abstract: A conceptual, continuous time model called SWAT (Soil and Water Assessment Tool) was developed to assist water resource managers in assessing the impact of management on water supplies and nonpoint source pollution in watersheds and large river basins. The model is currently being utilized in several large area projects by EPA, NOAA, NRCS and others to estimate the off-site impacts of climate and management on water use, nonpoint source loadings, and pesticide contamination. Model development, operation, limitations, and assumptions are discussed and components of the model are described. In Part II, a GIS input/output interface is presented along with model validation on three basins within the Upper Trinity basin in Texas.
Arnone E, Noto LV, Lepore C and Bras RL (2011), "Physically-based and distributed approach to analyze rainfall-triggered landslides at watershed scale", Geomorphology., October, 2011. Vol. 133(3-4), pp. 121-131.
Abstract: Landslides are a serious threat to life and property throughout the world. The causes of landslides are various since multiple dynamic processes are involved in driving slope failures. One of these causes is prolonged rainfall, which affects slope stability in different ways. Water infiltrating in a hillslope may cause a rise of the piezometric surface, which, in turn, involves an increase of the pore water pressure and a decrease of the soil shear resistance. For this reason, knowledge of spatio-temporal dynamics of soil water content, infiltration processes and groundwater dynamics, is of considerable importance in the understanding and prediction of landslides dynamics. In this paper a spatially distributed and physically based approach is presented, which embeds a slope failure method in a hydrological model. The hydrological model here used is the tRIBS model (Triangulated Irregular Network Real-Time Integrated Basin Simulator) that allows simulation of most of spatial-temporal hydrologic processes (infiltration, evapotranspiration, groundwater dynamics and soil moisture conditions) that can influence landsliding. Slope stability is assessed by implementing the infinite slope model in tRIBS. The model, based on geotechnical and geomorphological characteristics, classifies each computational cell as unconditionally stable or conditionally stable. Soil moisture conditions resulting from precipitation can trigger landslides at conditionally stable locations. When a landslide occurs, the model also computes the amount of detached soil and its possible path downslope. Model performance has been initially tested on a small catchment with very steep slopes, located in the northern part of Sicily (Italy), after a sensitivity analysis concerning some model parameters. (C) 2011 Elsevier B.V. All rights reserved.
van Asch TWJ, Malet J-P, van Beek LPH and Amitrano D (2007), "Techniques, issues and advances in numerical modelling of landslide hazard", Bulletin De La Societe Geologique De France. Vol. 178(2), pp. 65-88.
Abstract: Slope movements (e.g. landslides) are dynamic systems that are complex in time and space and closely linked to both inherited and current preparatory and triggering controls. It is not yet possible to assess in all cases conditions for failure, reactivation and rapid surges and successfully simulate their transient and multi-dimensional behaviour and development, although considerable progress has been made in isolating many of the key variables and elementary mechanisms and to include them in physically-based models for landslide hazard assessments. Therefore, the objective of this paper is to review the state-of-the-art in the understanding of landslide processes and to identify some pressing challenges for the development of our modelling capabilities in the forthcoming years for hazard assessment. This paper focuses on the special nature of slope movements and the difficulties related to simulating their complex time-dependent behaviour in mathematical, physically-based models. It analyses successively the research frontiers in the recognition of first-time failures (pre-failure and failure stages), reactivation and the catastrophic transition to rapid gravitational processes (post-failure stage). Subsequently, the paper discusses avenues to transfer local knowledge on landslide activity to landslide hazard forecasts on regional scales and ends with an outline how geomorphological investigations and supporting monitoring techniques could be applied to improve the theoretical concepts and the modelling performance of physically-based landslide models at different spatial and temporal scales.
Aschenwald J, Leichter K, Tasser E and Tappeiner U (2001), "Spatio-temporal landscape analysis in mountainous terrain by means of small format photography: A methodological approach", Ieee Transactions On Geoscience and Remote Sensing., April, 2001. Vol. 39(4), pp. 885-893.
Abstract: A method is presented in order to georectify high-oblique terrestrial images of high mountainous terrain taken by means of small-format camera. Using the distinct topographic situation of the study area located in a small alpine valley, an automatic camera has been mounted on the opposing hill slope providing daily photographs of the area of interest. To use the data in a geographic information system (GIS) a specific georectification method (JUKE method) was developed employing a digital elevation model (DEM), several reference and ground control points (GCPs), and the focal length of the lens, The method was useful for single-stage image rectification but was also applied successfully on pre-analyzed time-series images ("summary" images). Hence, the procedure enables the analysis of detailed, dynamic landscape ecological processes. Accuracy was mainly a measure of the quality of the GCPs, which were difficult to define in this remote area. The relatively economic data capturing and transforming procedure makes the method interesting for various applied disciplines in order to gain detailed spatio-temporal data. This method might be of considerable benefit, particularly in mountainous terrain where it is often difficult to capture continuous spatio-temporal information.
van Asselen S and Seijmonsbergen AC (2006), "Expert-driven semi-automated geomorphological mapping for a mountainous area using a laser DTM", Geomorphology., August, 2006. Vol. 78(3-4), pp. 309-320. Elsevier Science Bv.
Abstract: In this paper a semi-automated method is presented to recognize and spatially delineate geomorphological units in mountainous forested ecosystems, using statistical information extracted from a 1-m resolution laser digital elevation dataset. The method was applied to a mountainous area in Austria. First, slope angle and elevation characteristics were determined for each key geomorphological unit occurring in the study area. Second, a map of slope classes, derived from the laser DTM was used in an expert-driven multilevel object-oriented approach. The resulting classes represent units corresponding to landforms and processes commonly recognized in mountain areas: Fluvial terrace, Alluvial Fan, Slope with mass movement, Talus slope, Rock cliff, Glacial landform, Shallow incised channel and Deep incised channel. The classification result was compared with a validation dataset of geomorphological units derived from an analogue geomorphological map. For the above mentioned classes the percentages of correctly classified grid cells are 69%, 79%, 50%, 64%, 32%, 61%, 23% and 70%, respectively. The lower values of 32% and 23% are mainly related to inaccurate mapping of rock cliffs and shallow incised channels in the analogue geomorphological map. The accuracy increased to 76% and 54% respectively if a buffer is applied to these specific units. It is concluded that high-resolution topographical data derived from laser DTMs are useful for the extraction of geomorphological units in mountain areas. (c) 2006 Elsevier B.V. All rights reserved.
Asselman NEM, Middelkoop H and van Dijk PM (2003), "The impact of changes in climate and land use on soil erosion, transport and deposition of suspended sediment in the River Rhine", Hydrological Processes., November, 2003. Vol. 17(16), pp. 3225-3244.
Abstract: The objective of this study was to estimate the potential effects of changes in climate and land use on the mobilization of fine sediment and the net transport of wash load from the upstream basin to the lower Rhine delta. For this purpose, a suite of geographical information system-embedded models was developed that simulates the production, and transport of wash load through the drainage network and deposition on floodplains along the lower river reaches. The model results indicate that if climate changes in accordance with the UKHI climate-change scenario, in combination with land use changes, erosion rates will increase in the Alps and decrease in the German part of the basin. Averaged over the entire basin, erosion will increase by about 12%. However, due to inefficient sediment delivery, increasing erosion in the Alps will have little effect on the sediment load further downstream. In the delta area, sediment loads are expected to decrease by 13%. When changes in river discharge are accounted for, it appears that, although very high discharges are expected to occur more frequently, sedimentation on floodplains tends to decrease. This is caused mainly by reduced sediment loads at discharges during which the floodplains are just inundated and trapping efficiencies are high. Copyright (C) 2003 John Wiley Sons, Ltd.
Athapaththu A, Tsuchida T, Suga K and Kano S (2007), "A lightweight dynamic cone penetrometer for evaluation of shear strength of natural masado slopes", Doboku Gakkai Ronbunshuu C. Vol. 63(2), pp. 403-416. J-STAGE.
Abstract: This paper presents a simple methodology for determination of in situ shear strength parameters by recently developed lightweight dynamic cone penetrometer. A series of laboratory calibration lightweight dynamic cone penetration tests, and direct shear tests with pore water pressure measurements were conducted at different void ratios and degrees of saturation. Based on the laboratory calibration test results, a method of determining void ratio, e from the data of cone resistance, qd was established for different degrees of saturation. A method of determining shear strength parameters from the data of qd was proposed based on the correlations developed between void ratios with qd and shear parameters.
Auer I, Bohm R, Jurkovic A, Lipa W, Orlik A, Potzmann R, Schoner W, Ungersbock M, Matulla C, Briffa K, Jones P, Efthymiadis D, Brunetti M, Nanni T, Maugeri M, Mercalli L, Mestre O, Moisselin JM, Begert M, Muller-Westermeier G, Kveton V, Bochnicek O, Stastny P, Lapin M, Szalai S, Szentimrey T, Cegnar T, Dolinar M, Gajic-Capka M, Zaninovic K, Majstorovic Z and Nieplova E (2007), "HISTALP - historical instrumental climatological surface time series of the Greater Alpine Region", International Journal of Climatology., January, 2007. Vol. 27(1), pp. 17-46.
Abstract: This paper describes the HISTALP database, consisting of monthly homogenised records of temperature, pressure, precipitation, sunshine and cloudiness for the 'Greater Alpine Region' (GAR, 4-19 degrees E, 43-49 degrees N, 0-3500m asl). The longest temperature and air pressure series extend back to 1760, precipitation to 1800, cloudiness to the 1840s and sunshine to the 1880s. A systematic QC procedure has been applied to the series and a high number of inhomogeneities (more than 2500) and outliers (more than 5000) have been detected and removed. The 557 HISTALP series are kept in different data modes: original and homogenised, gap-filled and outlier corrected station mode series, grid-1 series (anomaly fields at 1 degrees x 1 degrees, lat x long) and Coarse Resolution Subregional (CRS) mean series according to an EOF-based regionalisation. The leading climate variability features within the GAR are discussed through selected examples and a concluding linear trend analysis for 100, 50 and 25-year subperiods for the four horizontal and two altitudinal CRSs. Among the key findings of the trend analysis is the parallel centennial decrease/increase of both temperature and air pressure in the 19th/20th century. The 20th century increase (+1.2 degrees C/+1.1 hPa for annual GAR-means) evolved stepwise with a first peak near 1950 and the second increase (1.3 degrees C/0.6hPa per 25 years) starting in the 1970s. Centennial and decadal scale temperature trends were identical for all subregions. Air pressure, sunshine and cloudiness show significant differences between low versus high elevations. A long-term increase of the high-elevation series relative to the low-elevation series is given for sunshine and air pressure. Of special interest is the exceptional high correlation near 0.9 between the series on mean temperature and air pressure difference (high-minus low-elevation). This, further developed via some atmospheric statics and thermodynamics, allows the creation of 'barometric temperature series' without use of the measures of temperature. They support the measured temperature trends in the region. Precipitation shows the most significant regional and seasonal differences with, e.g., remarkable opposite 20th century evolution for NW (9% increase) versus SE (9% decrease). Other long- and short-term features are discussed and indicate the promising potential of the new database for further analyses and applications. Copyright (c) 2006 Royal Meteorological Society.
Avanzi GD, Giannecchini R and Puccinelli A (2004), "The influence of the geological and geomorphological settings on shallow landslides. An example in a temperate climate environment: the June 19, 1996 event in northwestern Tuscany (Italy)", Engineering Geology., June, 2004. Vol. 73(3-4), pp. European Geophys Soc.
Abstract: On June 19, 1996, an extremely heavy rainstorm hit a restricted area in the Apuan Alps (northwestern Tuscany, Italy). Its max intensity concentrated over an area of about 150 km(2) astride the Apuan chain, where 474 min was recorded in about 12 h (21% of the mean annual precipitation, with an intensity up to 158 mm/h). The storm caused floods and hundreds of landslides and debris flows, which produced huge damage (hundreds of millions of Euros), partially destroyed villages and killed 14 people. This paper reports the results obtained from a detailed field survey and aerial view interpretation. In the most severely involved area, 647 main landslides were investigated, mapped and related to the geologic, geomorphic and vegetational factors of the source areas. This was in order to define the influence of these factors and contribute to an evaluation of the landslide hazard in the study area. An assessment was also made of the total area and volume of material mobilised by landsliding. The study area, about 46 km(2) wide, includes three typically mountainous basins, characterised by narrow, deep cut valleys and steep slopes, where many rock types outcrop. Most of the landslides were shallow and linear, referable to complex, earth and debris translational slide, which quickly developed into flow (soil slip-debris flow). Usually, they involved colluvium and started in hollows underlain by metamorphic rock (metasandstone and phyllite), often dipping downslope. Therefore, bedrock lithology and impermeability appeared to be important factors in the localisation of the landslide phenomena. The investigation of the geomorphic and land use features in the source areas also frequently highlighted a rectilinear profile of the slope, a high slope gradient (31-45degrees) and dense chestnut wood cover. In the area, about 985,000 m(2) (2.1% of 46 km(2)) was affected by landsliding and about 700,000 m(2) of this area was covered by chestnut forest. The landslides removed about 7000 trees. The volume of mobilised material was about 1,360,000 m(3); about 220,000 m(3) remained on the slopes, while the rest poured into the streams. In addition, about 945,000 m(3) was mobilised by the torrential erosion in the riverbeds. (C) 2004 Elsevier B.V. All rights reserved.
Ayalew L, Kasahara M and Yamagishi H (2011), "The spatial correlation between earthquakes and landslides in Hokkaido (Japan), a GIS-based analysis of the past and the future", Landslides., December, 2011. Vol. 8(4), pp. 433-448.
Abstract: Although earthquakes are thought to be one of the factors responsible for the occurrence of landslides in Hokkaido, there exist no enough records which can allow correlating many of the old slope failures in the island with earthquakes. In the absence of these records, an attempt was done in this study to use the abundance, frequency, magnitude, depth, and distribution of historical earthquakes to deduce that many of the slope failures in the region were triggered by strong and continuous seismicity. The determination of the zones of influences of selected earthquakes using an existing empirical function has also supported this conclusion. Moreover, the use of a 10% probability of exceedance of earthquake intensity in 50 years, and the geological and slope maps has allowed preparing a landslide hazard map which explains the role of future earthquakes in the formation of slope failures. The result indicates a high probability of occurrences of landslides in the hilly regions of the southeastern part of Hokkaido due to expected strong seismicity and earthquake intensities in these areas. On the other hand, the low level of intensity in the north has given rise to low probability of landslide hazard. There are also places in the center of the island and high intensity regions in the east where the probability of landslide hazard was influenced by the contribution of the geological and slope maps.
Bachri S and Shresta RP (2010), "Landslide hazard assessment using analytic hierarchy processing (AHP) and geographic information system in Kaligesing mountain area of Central Java Province Indonesia", In 5th Annual International Workshop & Expo on Sumatra Tsunami Disaster & Recovery. Banda Aceh, Indonesia, 23-24 November, 2010.
Abstract: Landslide is type of natural disaster which may cause huge losses of live and properties. Many landslides triggering factors found in Kaligesing make this zone as landslide prone area in Indonesia. Zoning hazard area was a solution to assess landslide disaster since there is still a great danger of further landslides in the region and also it is strongly linked with spatial issues. The combination of GIS and Analytic Hierarchy Process (AHP) are used to create landslide hazard zone in this study. Factors, such as landform, land utilization, slope steepness, soil texture and lithology are considered for use in AHP through pair-wise matrix. The output of calculation was validated with present landslide location. Based on the judgment matrix and calculation, the result showed ë max = 5.406256, the feature vector of normalization: F= 0.4042, 0.2746, 0.2018, 0.0845, 0.0349). In this calculation, RI =1.12. According to relational formula, CI=0.101564. A consistency ratio (CR) was computed to verify that the consistency of matrix. CR value of 0.090682, meant that the pair-wise matrix is consistent (threshold CR<0.10) and can be used for assigning the criteria weight. Spatial distribution of the susceptibility classes of landslide in Kaligesing showed that more than 40% of the study area was categorized as landslide prone area with moderate susceptibility and 30.05% falling on high susceptibility class, while the rest 20.78% was categorized as less susceptibility class.
Baenninger D (2007), "Technical Note: Water flow routing on irregular meshes", Hydrology and Earth System Sciences. Vol. 11(4), pp. 1243-1247.
Abstract: For spatially explicit hydrological modelling an algorithm was required that works as a cellular automata on irregular meshes. From literature it was found that the usual algorithms applied for this purpose do not route the water flow correctly between adjacent cells. In this study the hydraulic linking between mesh cells is done by calculating the flow cross section between the mesh cells. The flow cross sections are positioned in the centre of the mesh edges and are perpendicular to the local gradient of the digital elevation model. The presented algorithm is simple in its implementation and efficient in computation. It is shown that the proposed algorithm works correctly for different synthesised hill slope shapes.
Baeza C and Corominas J (2001), "Assessment of shallow landslide susceptibility by means of multivariate statistical techniques", Earth Surface Processes and Landforms., November, 2001. Vol. 26(12), pp. 1251-1263. John Wiley & Sons Ltd.
Abstract: Several multivariate statistical analyses have been performed to identify the most influential geological and Geomorphological parameters on shallow landsliding and to quantify their relative contribution. A data set was first prepared including more than 30 attributes of 230 failed and unfailed slopes. The performance of principal component analysis, t-test and one-way test, allowed a preliminary selection of the most significant variables, which were used as input variables for the discriminant analysis. The function obtained has classified successfully 88.5 per cent of the overall slope population and 95.6 per cent of the failed slopes. Slope gradient, watershed area and land-use appeared as the most powerful discriminant factors. A landslide susceptibility map, based on the scores of the discriminant function, has been prepared for Ensija range in the Eastern Pyrenees. An index of relative landslide density shows that the results of the map are consistent. Copyright (C) 2001 John Wiley & Sons, Ltd.
BAFU (2009), "Rutschungen - Gefährdung und Überwachung. Informationsblatt.".
BAFU (2009), "Rutschungen - Dynamik. Informationsblatt.".
BAFU (2009), "Rutschungen - Ursachen. Informationsblatt.".
BAFU (2009), "Rutschungen - Prozess. Informationsblatt.".
Bai S, Wang J, Zhang Z and Cheng C (2012), "Combined landslide susceptibility mapping after Wenchuan earthquake at the Zhouqu segment in the Bailongjiang Basin, China", Catena., December, 2012. Vol. 99, pp. 18-25.
Abstract: In this study, two separate landslide susceptibility maps using multi-temporal landslide and Wenchuan earthquake triggered landslide datasets were carried out based on GIS and logistic regression model at Zhouqu segment in the Bailongjiang Basin in North-western China. This region has already been strongly affected by landslides for a long time, and numerous additional slope failures were triggered by the 2008 Wenchuan earthquake. The data used for this study consists of two landslide inventories, of which the first lists historical landslides and the latter contains only slope failures attributed to the 2008 earthquake. Additional data sources include landslide causative factor such as a digital elevation model (DEM) with a 30x30 m(2) resolution, orthophotos, geological and land-use maps, precipitation records and information on peak ground acceleration data from the 2008 earthquake. The comparison of the two computed maps shows that susceptibility classes are consistent for over 58% of study area. Changes of one or more classes were observed for approximately 36% and 6%, respectively. Finally, both susceptibility maps were combined to describe the maximum likelihood of landslide occurrences. The overall high prediction rates of the calculated susceptibility maps make them an ideal basis for the use within regional spatial planning as well as for the organization of emergency actions by local authorities. (C) 2012 Elsevier B.V. All rights reserved.
Balteanu D, Chendes V, Sima M and Enciu P (2010), "A country-wide spatial assessment of landslide susceptibility in Romania", Geomorphology., December, 2010. Vol. 124(3-4), pp. 102-112.
Abstract: This paper proposes a brief spatial analysis of landslides in Romania, completed by a landslide susceptibility model. Landslides constitute a very common geomorphic hazard in this country, mainly in the hilly regions which occupy around 30% of Romania's territory. The landslide susceptibility assessment at national level was accomplished using a Landslide Susceptibility Index (LSI) computed in GIS, which considers and weights the main factors that control landslide activity: lithology, slope gradient, maximum rainfall in 24 h, land use, seismicity and local relief. Each factor was classified into 7-18 classes which were rated from 1 to 10 by means of expert judgement. A formula was devised to compute the landslide Susceptibility Index over each 100 m x 100 m pixel and the resulting values were ranked into 5 landslide susceptibility classes. This synthetic method of landslide susceptibility assessment, applied to the whole country, is a useful tool to evaluate the distribution of landslide-prone areas, as well as to validate and to enhance some results obtained in previous studies based on field research and map interpretation. The most landslide-prone areas correspond to the Subcarpathians (an outer fringe of hilly terrain accompanying the Carpathians), as well as to the Moldavian Plateau in the east. The semi-quantitative approach has been validated with satisfactory results in a particular sector using independent cartographic landslide inventories. (C) 2010 Elsevier By. All rights reserved.
Bänninger D, Brodbeck M, Hohwieler N, Meusburger K and Alewell C (2006), "Soil Degradation in the Swiss Alps", In Mountain Forum Bulletin. Vol. VI(2), pp. 41. Mountain Forum.
Barnard PL, Rubin DM, Harney J and Mustain N (2007), "Field test comparison of an autocorrelation technique for determining grain size using a digital 'beachball' camera versus traditional methods", Sedimentary Geology., September, 2007. Vol. 201(1-2), pp. 180-195.
Abstract: This extensive field test of an autocorrelation technique for determining grain size from digital images was conducted using a digital bed-sediment camera, or 'beachball' camera. Using 205 sediment samples and >1200 images from a variety of beaches on the west coast of the US, grain size ranging from sand to granules was measured from field samples using both the autocorrelation technique developed by Rubin [Rubin, D.M., 2004. A simple autocorrelation algorithm for determining grain size from digital images of sediment. Journal of Sedimentary Research, 74(l): 160-165.] and traditional methods (i.e. settling tube analysis, sieving, and point counts). To test the accuracy of the digital-image grain size algorithm, we compared results with manual point counts of an extensive image data set in the Santa Barbara littoral cell. Grain sizes calculated using the autocorrelation algorithm were highly correlated with the point counts of the same images (r(2) = 0.93; n = 79) and had an error of only 1%. Comparisons of calculated grain sizes and grain sizes measured from grab samples demonstrated that the autocorrelation technique works well on high-energy dissipative beaches with well-sorted sediment such as in the Pacific Northwest (r(2) >= 0.92; n = 115). On less dissipative, more poorly sorted beaches such as Ocean Beach in San Francisco, results were not as good (r(2) >= 0.70; n = 67; within 3% accuracy). Because the algorithm works well compared with point counts of the same image, the poorer correlation with grab samples must be a result of actual spatial and vertical variability of sediment in the field; closer agreement between grain size in the images and grain size of grab samples can be achieved by increasing the sampling volume of the images (taking more images, distributed over a volume comparable to that of a grab sample). In all field tests the autocorrelation method was able to predict the mean and median grain size with similar to 96% accuracy, which is more than adequate for the majority of sedimentological applications, especially considering that the autocorrelation technique is estimated to be at least 100 times faster than traditional methods. Published by Elsevier B.V.
Bathurst JC, Bovolo CI and Cisneros F (2010), "Modelling the effect of forest cover on shallow landslides at the river basin scale", Ecological Engineering., March, 2010. Vol. 36(3), pp. 317-327. Elsevier Science Bv.
Abstract: The potential for reducing the occurrence of shallow landslides through targeted reforestation of critical parts of a river basin is explored through mathematical modelling. Through the systematic investigation of land management options, modelling allows the optimum strategies to be selected ahead of any real intervention in the basin. Physically based models, for which the parameters can be evaluated using physical reasoning offer particular advantages for predicting the effects of possible future changes in land use and climate. Typically a physically based landslide model consists of a coupled hydrological model (for soil moisture) and a geotechnical slope stability model, along with an impact model, such as basin sediment yield. An application of the SHETRAN model to the 65.8-km(2) Guabalcon basin in central Ecuador demonstrates a technique for identifying the areas of a basin most susceptible to shallow landslicling and for quantifying the effects of different vegetation covers on landslide incidence. Thus, for the modelled scenario, increasing root cohesion from 300 to 1500 Pa causes a two-thirds reduction in the number of landslides. Useful information can be obtained even on the basis of imperfect data availability but model output should be interpreted carefully in the light of parameter uncertainty. (C) 2009 Elsevier B.V. All rights reserved.
Bathurst JC, Moretti G, El-Hames A, Moaven-Hashemi A, Burton A and others (2005), "Scenario modelling of basin-scale, shallow landslide sediment yield, Valsassina, Italian Southern Alps", Natural Hazards and Earth System Science. Vol. 5(2), pp. 189-202.
Abstract: The SHETRAN model for determining the sediment yield arising from shallow landsliding at the scale of a river catchment was applied to the 180-km2 Valsassina basin in the Italian Southern Alps, with the aim of demonstrating that the model can simulate long term patterns of landsliding and the associated sediment yields and that it can be used to explore the sensitivity of the landslide sediment supply system to changes in catchment characteristics. The model was found to reproduce the observed spatial distribution of landslides from a 50-year record very well but probably with an overestimate of the annual rate of landsliding. Simulated sediment yields were within the range observed in a wider region of northern Italy. However, the results suggest that the supply of shallow landslide material to the channel network contributes relatively little to the overall long term sediment yield compared with other sources. The model was applied for scenarios of possible future climate (drier and warmer) and land use (fully forested hillslopes). For both scenarios, there is a modest reduction in shallow landslide occurrence and the overall sediment yield. This suggests that any current schemes for mitigating sediment yield impact in Valsassina remain valid. The application highlights the need for further research in eliminating the large number of unconditionally unsafe landslide sites typically predicted by the model and in avoiding large overestimates of landslide occurrence.
Baum RL, Coe JA, Godt JW, Harp EL, Reid ME, Savage WZ, Schulz WH, Brien DL, Chleborad AF, McKenna JP and Michael JA (2005), "Regional landslide-hazard assessment for Seattle, Washington, USA", Landslides., December, 2005. Vol. 2(4), pp. 266-279.
Abstract: Landslides are a widespread, frequent, and costly hazard in Seattle and the Puget Sound area of Washington State, USA. Shallow earth slides triggered by heavy rainfall are the most common type of landslide in the area; many transform into debris flows and cause significant property damage or disrupt transportation. Large rotational and translational slides, though less common, also cause serious property damage. The hundreds of landslides that occurred during the winters of 1995-96 and 1996-97 stimulated renewed interest by Puget Sound communities in identifying landslide-prone areas and taking actions to reduce future landslide losses. Informal partnerships between the U.S. Geological Survey (USGS), the City of Seattle, and private consultants are focusing on the problem of identifying and mapping areas of landslide hazard as well as characterizing temporal aspects of the hazard. We have developed GIS-based methods to map the probability of landslide occurrence as well as empirical rainfall thresholds and physically based methods to forecast times of landslide occurrence. Our methods for mapping landslide hazard zones began with field studies and physically based models to assess relative slope stability, including the effects of material properties, seasonal groundwater levels, and rainfall infiltration. We have analyzed the correlation between historic landslide occurrence and relative slope stability to map the degree of landslide hazard. The City of Seattle is using results of the USGS studies in storm preparedness planning for emergency access and response, planning for development or redevelopment of hillsides, and municipal facility planning and prioritization. Methods we have developed could be applied elsewhere to suit local needs and available data.
Baum RL and Godt JW (2010), "Early warning of rainfall-induced shallow landslides and debris flows in the USA", Landslides., September, 2010. Vol. 7(3), pp. 259-272.
Abstract: The state of knowledge and resources available to issue alerts of precipitation-induced landslides vary across the USA. Federal and state agencies currently issue warnings of the potential for shallow, rapidly moving landslides and debris flows in a few areas along the Pacific coast and for areas affected by Atlantic hurricanes. However, these agencies generally lack resources needed to provide continuous support or to expand services to other areas. Precipitation thresholds that form the basis of landslide warning systems now exist for a few areas of the USA, but the threshold rainfall amounts and durations vary over three orders of magnitude nationwide and over an order of magnitude across small geographic areas such as a county. Antecedent moisture conditions also have a significant effect, particularly in areas that have distinct wet and dry seasons. Early warnings of shallow landslides that include specific information about affected areas, probability of landslide occurrence, and expected timing are technically feasible as illustrated by a case study from the Seattle, WA area. The four-level warning scheme (Null, Outlook, Watch, Warning) defined for Seattle is based on observed or predicted exceedance of a cumulative precipitation threshold and a rainfall intensity-duration threshold combined with real-time monitoring of soil moisture. Based on analysis of historical data, threshold performance varies according to precipitation characteristics, and threshold exceedance corresponds to a given probability of landslide occurrence. Experience in Seattle during December 2004 and January 2005 illustrates some of the challenges of providing landslide early warning on the USA West Coast.
Baum RL, Godt JW and Sacage WZ (2010), "Estimating the timing and location of shallow rainfall-induced landslides using a model for transient, unsaturated infiltration", Journal of Geophysical Research. Vol. 115
Abstract: Shallow rainfall-induced landslides commonly occur under conditions of transient infiltration into initially unsaturated soils. In an effort to predict the timing and location of such landslides, we developed a model of the infiltration process using a two-layer system that consists of an unsaturated zone above a saturated zone and implemented this model in a geographic information system (GIS) framework. The model links analytical solutions for transient, unsaturated, vertical infiltration above the water table to pressure-diffusion solutions for pressure changes below the water table. The solutions are coupled through a transient water table that rises as water accumulates at the base of the unsaturated zone. This scheme, though limited to simplified soil-water characteristics and moist initial conditions, greatly improves computational efficiency over numerical models in spatially distributed modeling applications. Pore pressures computed by these coupled models are subsequently used in one-dimensional slope-stability computations to estimate the timing and locations of slope failures. Applied over a digital landscape near Seattle, Washington, for an hourly rainfall history known to trigger shallow landslides, the model computes a factor of safety for each grid cell at any time during a rainstorm. The unsaturated layer attenuates and delays the rainfall-induced pore-pressure response of the model at depth, consistent with observations at an instrumented hillside near Edmonds, Washington. This attenuation results in realistic estimates of timing for the onset of slope instability (7 h earlier than observed landslides, on average). By considering the spatial distribution of physical properties, the model predicts the primary source areas of landslides.
Baum RL, Savage WZ and Godt JW (2008), "TRIGRS- A Fortran Program for Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability Analysis, Version 2. 0"
Abstract: TRIGRS (Transient Rainfall Infiltration and Grid-based Regional Slope-Stability Model) is a Fortran program for computing transient pore-pressure changes, and attendant changes in the factor of safety, due to rainfall infiltration using the method outlined by Iverson (2000). We have extended Iverson's (2000) method by implementing the solution for complex storms, a solution for additional basal boundary conditions, and a simple runoff-routing scheme. The program operates on a gridded elevation model of a map area and accepts input from a series of ASCII text files. Infiltration, hydraulic properties, and slope stability input parameters are allowed to vary over the grid area thus making it possible to analyze complex storm sequences over geologically complex terrain. The optional routing scheme achieves mass balance between rainfall input, infiltration, and runoff over the entire grid by allowing excess water to flow to downslope cells that are receiving less direct precipitation than they are able to absorb. The program saves output to a series of text files that can be imported to GIS software for display or further analysis.
Analyses using TRIGRS are applicable to areas that are prone to shallow precipitation-induced landslides and that satisfy other model assumptions reasonably well. These assumptions include nearly saturated soil, a well-documented flow field and relatively isotropic, homogeneous hydrologic properties. The saturated soil assumption is approximately satisfied during the winter rainy season in parts of the U.S. Pacific coast region (Baum and others, 2002). Significant hydraulic heterogeneity may cause errors at boundaries between materials of differing hydraulic properties because TRIGRS uses infiltration models for a homogeneous, isotropic medium. However, we have not evaluated the magnitude of such possible errors. Model results are very sensitive to the initial conditions, particularly the steady component of the flow field and initial depth of the water table. Consequently, the model may produce questionable results where the initial water table depth is poorly constrained.
TRIGRS runs in a simple input/output window with relatively little user interaction. The user controls an analysis by means of an initialization file that contains the names of all other input and output files as well as other parameters needed to run the program. The following discussion will briefly describe system requirements for running the program, installation, features and limitations of the program, and provide a detailed description of the initialization file. A tutorial helps familiarize the user with program features and operation.
Baumgartner H-J (2007), "Ganze Berghänge in Bewegung", Umwelt., In Umwelt. Vol. 2, pp. 18-20.
Abstract: Dass Hänge abrutschen, gehört zum Lauf der Erdgeschichte, die nie zu Ende ist. In mehreren Gebieten der Schweiz sind permanente Rutschungen teils schon seit Jahrtausenden in Gang. Zunehmend geraten nun auch die auftauenden Permafrostböden in höheren Lagen in Bewegung. Ein satellitengestütztes Überwachungssystem hilft, diese Gefahren rechtzeitig zu erkennen und ihnen auszuweichen.
Becht M (1994), "Investigations of slope erosion in the northern limestone Alps", Lecture Notes in Earth Sciences. Vol. 52, pp. 171-193.
Abstract: With reference to the Kesselbach valley in the Northern Limestone Alps as an example, the relationship between slope erosion and sediment load yield of the catchnmm area is prevented. Slope erosion is predominated by gravitational processes (debris flows, avalanches). Fluvial erosion prevails only where these processes are not active (forested areas, gentle slopes). Comparing slope erosion with the sediment load yield of the catchment area of the Kesselbach shows a clear predominance of the latter. The solids are eroded in the cuts of the V-shaped valleys. Thus, there is present-day intensive further formation of these valleys, which dominate the scenery.
Becker M (2005), "Entwicklung von computergestützten Hangstabilitätsmodellen zur Erstellung einer Gefahrenhinweiskarte für die Region Rheinhessen". Thesis at: Johannes Gutenberg-Universität Mainz.
Abstract: Das Ziel dieser Arbeit war die Entwicklung computergestützter Methoden zur Erstellung einer Gefahrenhinweiskarte für die Region Rheinhessen zur Minimierung der Hangrutschungsgefährdung. Dazu wurde mit Hilfe zweier statistischer Verfahren (Diskriminanzanalyse, Logistische Regression) und einer Methode aus dem Bereich der Künstlichen Intelligenz (Fuzzy Logik) versucht, die potentielle Gefährdung auch solcher Hänge zu klassifizieren, die bis heute noch nicht durch Massenbewegungen aufgefallen sind. Da ingenieurgeologische und geotechnische Hanguntersuchungen aus Zeit und Kostengründen im regionalen Maßstab nicht möglich sind, wurde auf punktuell vorhandene Datenbestände zu einzelnen Rutschungen (etwa 200 Stück) des Winters 1981/82, die in einer Rutschungsdatenbank zusammengefaßt sind, zurückgegriffen, wobei die daraus gewonnenen Erkenntnisse über Prozeßmechanismen und auslösende Faktoren genutzt und in das jeweilige Modell integriert wurden. Flächenhafte Daten (Lithologie, Hangneigung, Landnutzung, etc.), die für die Berechnung der Hangstabilität notwendig sind, wurden durch Fernerkundungsmethoden, dem Digitalisieren von Karten und der Auswertung von Digitalen Geländemodellen (Reliefanalyse) gewonnen. Für eine weiterführende Untersuchung von einzelnen, als rutschgefährdet klassifizierten Bereichen der Gefahrenhinweiskarte, wurde am Beispiel eines Testgebietes, eine auf dem infinite-slope-stability Modell aufbauende Methode untersucht, die im Maßstabsbereich von Grundkarten (1:5000) auch geotechnische und hydrogeologische Parameter berücksichtigt und damit eine genauere, der jeweiligen klimatischen Situation angepaßte, Gefahrenabschätzung ermöglicht.
Becker M, Rödelsperger S, Läufer G and Schneider J (2012), "Erfassung von hochfrequenten und langfristigen Deformationsprozessen mit terrestrischer Mikrowelleninterferometrie", Vermessung und Geoinformation. , pp. 29-35.
Abstract: In den letzten 10 Jahren hat sich die terrestrische Mikrowelleninterferometrie zu einem wichtigen Instrument bei der Beobachtung von Massenbewegungen und Bauwerken entwickelt. Das Messverfahren ermöglicht sowohl das wiederholte Erfassen von langfristigen Deformationen flächenhafter Objekte (2D), als auch die Bestimmung von hochfrequenten Bewegungen eines Profils (1D). Dieser Vortrag stellt die technischen und physikalischen Grundlagen des Mess- und Auswerteverfahrens dar und zeigt drei Anwendungsbeispiele. Die Anwendungsmöglichkeiten dieser Technik sind vielfältig und reichen von der Bestimmung von modalen Parametern (Eigenfrequenz, Eigenform, Dämpfung) von Bauwerken wie Brücken und Türmen bis hin zu Monitoring von Bewegungen im Bergbau, an Hangrutschungen, Gletschern, Vulkanen und Staudämmen. Die wesentlichen Vorteile der Technik gegenüber herkömmlichen Verfahren sind das berührungslose Messen (d.h. kein Zugang zum Objekt ist erforderlich), sowie die Unabhängigkeit von Tageslicht und Wetterverhältnissen.
Begueria S (2006), "Changes in land cover and shallow landslide activity: A case study in the Spanish Pyrenees", Geomorphology., March, 2006. Vol. 74(1-4), pp. 196-206.
Abstract: The Pyrenees, like many other mountain areas in Europe, have experienced depopulation and land abandonment during the 20th century. This has encouraged vegetation recovery in formerly occupied areas, including reforestation to promote woodland. The objective of this study is to analyse the effects of these changes on shallow landsliding, a process responsible for erosion and land degradation in many mountain areas. A sequence of aerial images reveals a slight decrease in the landslide occurrence rate in the last half of the 20th century and a parallel increase in the landslide extinction rate, i.e. the rate at which evidence of landslide activity is removed by vegetation colonisation. A logistic regression routine was used to assess the influence of land use and vegetation recovery in the occurrence of shallow landslides. The result shows that the former arable fields on the valley slopes still facilitate landsliding, even after land abandonment and revegetation by shrubs or trees. A shift in the topographic location of landslides was also detected, pointing to an increased importance of water redistribution in the slopes after prolonged rainfall periods. (c) 2005 Elsevier B.V. All rights reserved.
Behrens T, Schmidt K, Zhu AX and Scholten T (2010), "The ConMap approach for terrain-based digital soil mapping", European Journal of Soil Science. Vol. 61(1), pp. 133-143. Blackwell Publishing Ltd.
Abstract: We present a new digital terrain analysis framework for digital soil mapping, referred to as contextual elevation mapping (ConMap). In contrast to common regression approaches based on features from digital terrain analysis, ConMap is not based on standard terrain attributes, but on elevation differences from the centre pixel to each pixel in circular neighbourhoods only. These differences are used as features in random forest regressions. We applied and validated the framework by predicting topsoil silt content in a loess region of 1150 km2 in Rhineland-Palatinate and Hesse, Germany. Three hundred and forty-two samples and a 20-m resolution digital elevation model were used for this illustration and validation. We compared ConMap with standard and multi-scale terrain analysis approaches as well as with ordinary kriging interpolations. Cross-validation root mean square error (RMSE) decreased from 16.1 when the standard digital terrain analysis was used to 11.2 when ConMap was used. This corresponds to an increase in variance explained (R2) from 15 to 61%. Even though ordinary kriging out-performed standard terrain analysis as well, the variance explained was 6% smaller compared with that using ConMap. The results show that the geomorphic settings in the study area must have induced the spatial trend, which can be accounted for by ConMap over different scales. We conclude that ConMap shows great potential for digital soil mapping studies.
Bell R (2007), "Lokale und regionale Gefahren- und Risikoanalyse gravitativer Massenbewegungen an der Schwäbischen Alb". Thesis at: University of Bonn, Institute of Geography.
Bell R, Petschko H, Rohrs M and Dix A (2012), "Assessment of Landslide Age, Landslide Persistence and Human Impact Using Airborne Laser Scanning Digital Terrain Models", Geografiska Annaler Series A-physical Geography. Vol. 94A(1), pp. 135-156.
Abstract: Landslides occur worldwide and contribute significantly to sediment budgets as well as to landform evolution. Furthermore, they pose hazards and risks to people and their goods. To assess the role of landslides, information on their age or persistence (i.e. the length of time the morphological characteristics of a landslide remain recognizable in the terrain) is essential. In this study, the potential of airborne laser scanning digital terrain models (ALS DTMs) is analysed for estimating landslide age, landslide persistence and human impact. Therefore, landslides in two study areas, Swabian Alb in Germany and Lower Austria in Austria, are mapped from hillshades of ALS DTMs and combined with historical information on landslide occurrence. It is tested whether the modification of the geomorphological features of landslides can be used to assess landslide age. In the Swabian Alb older landslides might show fresher features than younger ones because of different degrees of human impact, natural erosion and different histories of landslide reactivation. Estimated persistence times range between 27 and 320 years but are minimum values only. In Lower Austria four landslides show estimated minimum persistence times between 4 and 28 years. In Lower Austria 27 landslides disappeared in less than 7 years after occurrence mainly because of planation by farmers. The results show no clear trend in landslide persistence, neither regarding landslide magnitude, nor regarding land use. However, it is evident that human impact plays a major role in landslide persistence.
Beniston M (2006), "Mountain weather and climate: A general overview and a focus on climatic change in the Alps", Hydrobiologia., June, 2006. Vol. 562, pp. 3-16.
Abstract: Meteorological and climatic processes in mountain regions play a key role in many environmental systems, in particular the quantity and quality of water that influences both aquatic ecosystems and economic systems often far beyond the boundaries of the mountains themselves. This paper will provide a general overview of some of the particular characteristics of mountain weather and climate, to highlight some of the unique atmospheric features that are associated with regions of complex topography. The second part of the paper will focus upon characteristics of climate and climatic change in the European Alps, a region with a wealth of high quality data that allows an assessment on how climate and dependent environmental systems have evolved in the course of the 20th century and how alpine climate may undergo further changes to "global warming" in the 21st century, as the atmosphere responds to increasing levels of greenhouse gases that are expected in coming decades.
Berg P, Moseley C and Haerter JO (2013), "Strong increase in convective precipitation in response to higher temperatures", Nature Geoscience. Vol. 6, pp. 181-185.
Abstract: Precipitation changes can affect society more directly than variations in most other meteorological observables1–3, but precipitation is difficult to characterize because of fluctuations on nearly all temporal and spatial scales. In addition, the intensity of extreme precipitation rises markedly at higher temperature4–9, faster than the rate of increase in the atmosphere’s water-holding capacity1,4, termed the Clausius–Clapeyron rate. Invigoration of convective precipitation (such as thunderstorms) has been favoured over a rise in stratiform precipitation (such as large-scale frontal precipitation) as a cause for this increase4,10, but the relative contributions of these two types of precipitation have been difficult to disentangle. Here we combine large data sets from radar measurements and rain gauges over Germany with corresponding synoptic observations and temperature records, and separate convective and stratiform precipitation events by cloud observations. We find that for stratiform precipitation, extremes increase with temperature at approximately the Clausius–Clapeyron rate, without characteristic scales. In contrast, convective precipitation exhibits characteristic spatial and temporal scales, and its intensity in response to warming exceeds the Clausius– Clapeyron rate. We conclude that convective precipitation responds much more sensitively to temperature increases than stratiform precipitation, and increasingly dominates events of extreme precipitation.
Bernhaupt P (1980), "Zum Problem der Bodenerosion in Almgebieten am Beispiel der Planneralm, Wölzer Tauern, Steiermark", In Proc. of the IV International Congress Interpraevent 1980, Bad Ischl. Bad Ischl Vol. 1, pp. 291-308.
Abstract: Im Bereich der Plan neralm treten an den S-SW-exponierten Glallhängen, die 20 - 35° geneigt sind, B1aiken (Grasnarbenrutschungen) auf. Innerhalb von 24 Jahren hat sich die Denudati onsniiche verdoppelt. Fehlender Weidegang und fehle nde Almpnege, somit Ex tensivierung der Almwirtschaft im Zuge eines tiefgreifenden kulturgeographischen Funktionswandels, müssen dafür verantwortlich gemacht werden.
Bertle H (1984), "Bericht 1983 über geologische Aufnahmen auf Blatt 112 Bezau", Jb. Geol. B.-A. Wien. Vol. 127, pp. 229-229.
Beven K and Germann P (1982), "Macropores and Water-flow In Soils", Water Resources Research. Vol. 18(5), pp. 1311-1325. Amer Geophysical Union.
Beven K and Kirkby M (1979), "A physically based, variable contributing area model of basin hydrology", Hydrol. Sci. Bull.. Vol. 24(1), pp. 43-69.
Bezzola G and Hegg C (2008), "Ereignisanalyse Hochwasser 2005, Teil 2 - Analyse von Prozessen, Maßnahmen und Gefahrengrundlagen", In Umweltwissen: 0825. , pp. 429. Bundesamt für Umwelt BAFU, Eidgenössische Forschungsanstalt WSL.
Bezzola G and Hegg C (2007), "Ereignisanalyse Hochwasser 2005, Teil 1 - Prozesse, Schäden und erste Einordnung", In Umweltwissen: 0707. , pp. 215. Bundesamt für Umwelt BAFU, Eidgenössische Forschungsanstalt WSL.
Bezzola GR, Hegg C and Koschni A (2008), "Synthesebericht Hochwasser 2005 in der Schweiz"
Bianchi Fasani G, Bozzano F, Esposito C, Manuel MR, Martino S, Prestininzi A and Scarascia Mugnozza G (2004), "An example of earthquake triggered landslide in structurally complex formations", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 2, pp. 321-326. Taylor & Francis.
Birkenhauer J (2001), "Blaiken in den Alpen - Ursachen und Verbreitung", Mitteilungen der Geographischen Gesellschaft München. Vol. 85, pp. 1-17.
Abstract: Die wesentliche Absicht des Beitrages besteht darin, einen alpenweiten Überblick über das Phänomen "Blaiken" zu gewinnen und damit zu einer Gesamteinordnung zu gelangen. Einzelforschungen sind absolut unerläßlich - aber Geographie muß als Regionalforschung über die Einzelfälle hinauskommen - sonst handelte es sich nicht mehr um Geographie. Die Darstellung stützt sich aufwiederholte und ausgedehnte Beobachtungen in weitesten Teilen der Alpen, die seit 1969 angestellt worden sind. Räumliche Weite verbindet sich mit zeitlicher Tiefe.
Bishop MP, James LA, Shroder JFJ and Walsh SJ (2012), "Geospatial technologies and digital geomorphological mapping: Concepts, issues and research", Geomorphology., January, 2012. Vol. 137(1), pp. 5-26.
Abstract: Geomorphological mapping plays an essential role in understanding Earth surface processes, geochronology, natural resources, natural hazards and landscape evolution. It involves the partitioning of the terrain into conceptual spatial entities based upon criteria that include morphology (form), genetics (process), composition and structure, chronology, environmental system associations (land cover, soils, ecology), as well as spatial topological relationships of surface features (landforms). Historically, the power of human visualization was primarily relied upon for analysis, introducing subjectivity and biases with respect to selection of criteria for terrain segmentation and placement of boundaries. This paper reviews new spatiotemporal data and geocomputational approaches that now permit Earth scientists to go far beyond traditional mapping, permitting quantitative characterization of landscape morphology and the integration of varied landscape thematic information. Numerous conceptual, theoretical, and information-technology issues are at the heart of digital geomorphological mapping (DGM), and scientific progress has not kept pace with new and rapidly evolving geospatial technologies. Consequently, new capabilities exist but numerous issues have not been adequately addressed. Therefore, this paper discusses conceptual foundations and illustrates how geomorphometry and mapping approaches can be used to produce geomorphological information related to the land surface and landforms, process rates, process-form relationships, and geomorphic systems. (C) 2011 Elsevier B.V. All rights reserved.
Bitelli G, Dubbini M and Zanutta A (2004), "Terrestrial laser scanning and digital photogrammetry to monitor landslide bodies", In Proceedings of the XXth ISPRS Congress, Instanbul, Vol. XXXV, part B5. Istanbul , pp. 246-251.
Abstract: Photogrammetry and laser scanning, thanks to significant development in last years, are comparable surveying techniques to generate - without object contact and with a precision commensurate with scale - Digital Terrain Models (DTMs), a fundamental tool to detect, classify and monitoring landslides. The traditional way to survey the territory for landslide detection purposes is aerial or, in some cases, terrestrial photogrammetry, that permits to carry out 3D models of the terrain and, by means of DTMs comparisons, to realise multi-temporal studies. The massive introduction of modern digital photogrammetric workstations, with automatic matching procedures, allows for a rapid DTM production for landslide monitoring activities. On the other hand, the 3D reconstruction of the terrain with terrestrial laser scanning methods is another modern way to reproduce the natural surface of the ground with high accuracy and high automation. There are however some open problems concerning the elaboration of the data and the procedures to generate DTM starting from Digital Surface Models (DSMs), taking off vegetation, buildings, etc. The present work describes the terrestrial laser scanning and photogrammetric surveys realised on a small landslide body located on the Northern Apennines in Italy (municipality of Vergato, Bologna), an interesting case in order to test the laser scanning capabilities and the procedure of laser data processing, also in comparison with photogrammetry.
Bittelli M, Valentino R, Salvatorelli F and Pisa PR (2012), "Monitoring soil-water and displacement conditions leading to landslide occurrence in partially saturated clays", Geomorphology., November, 2012. Vol. 173, pp. 161-173.
Abstract: Shallow landslides frequently occur during transient rainfall infiltration and under partially saturated conditions. However, a detailed analysis of what triggers them, particularly in clayey soils, is often hindered by the lack of field measurements. It is uncommon, in fact, to capture their occurrence in an instrumented natural slope. This paper presents results from an integrated field experiment monitoring the soil-water and displacement conditions :hat lead to the occurrence of a shallow landslide in partially saturated clays. The integration of a variety of experimental techniques allowed for the examination of interplay between soil hydrological and mechanical properties. This research also evaluates a slope stability model based on the suction stress concept. Since the model was applied after the occurrence of the landslide, the results are interpreted as a hind-casting technique for model evaluation. Nevertheless, the detailed field measurements acquired during the monitoring activity and the occurrence of a landslide during the experiment provided significant information on model parameters and data interpretation. The station provides remote satellite monitoring of data on weather variables, soil water content and soil suction. A time domain reflectometry cable was installed vertically to detect potential soil failure. The experimental area had a high probability of landslide occurrence. Indeed, slope failure occurred during the observation period, showing the effectiveness of the station in detecting the occurrence, time and depth of landslides. The landslide was triggered in consequence of changes in suction stress. The failure plane occurred at a depth of 1.4 m. corresponding to the interface between a superficial layer of higher permeability of 1 to 1.45 m thickness, slipping over a compacted substrate having lower permeability. The analysis allowed for testing of the validity of the model and the description of the triggering mechanisms of the observed shallow landslide in unsaturated conditions, indicating that oscillations in soil matric suction were the dominant variables determining soil failure. (C) 2012 Elsevier B.V. All rights reserved.
Bitterlich W (1998), "Auswirkungen unterschiedlicher Bewirtschaftungen auf Boden und Vegetation am Beispiel der Kaserstattalm / Neustift im Stubaital". Thesis at: University of Innsbruck, Institute of Botany.
Blechschmidt G (1990), "Die Blaikenbildung im Karwendel", Jahrbuch des Vereins zum Schutz der Bergwelt. Vol. 55, pp. 31-45.
BLU (2012), "Georisiken im Klimawandel - Gefahrenhinweiskarte Bayerische Alpen"
Blum W, Englisch M, Freudenschuß A, Nelhiebel P, Pock H, Schneider W, Schwarz S, Wagner J and Wandl M (2005), "Soil Survey and Soil Data in Austria", European Soil Bureau Research Report. Vol. 9, pp. 47-61.
Abstract: There are three principal systems of soil survey in Austria: on forested land the Forest Soil Survey, on agricultural land, the Soil Taxation Survey and the Soil Management Survey. In addition, there is an Environmental Soil Survey, a Soil Monitoring System and a Soil Information System (BORIS). Each of these is described below.
Blume U and Reichenbach H (2008), "Leichte Rammsonde mit variabler Rammenergie zur Baugrunduntersuchung und zur Verdichtungskontrolle", Straße und Autobahn. Vol. 1, pp. 5-11.
Abstract: Die französische Panda-Sonde ist ein Prüfgerät zur Bodenuntersuchung und Verdichtungskontrolle. Im Unterschied zu den Rammsondenmit konstanterRammenergiegemäß DINEN 22476 wirddie Rammenergiebei der panda-Sonde variabel durch Hammerschläge erzeugt. Wegen des relativ geringen Energieeintrages wird eine detaillierte Auflösung der durchteuften Bodenschichten erreicht. Außerdem ist die Sonde aufgrund ihrer geringen Abmessungen und ihres geringen Gewichtes auch zur Untersuchung schwer zugänglicher Geländepunkte, für Hinterfüllungen, in Rohrgräben sowie für horizontale Untersuchungen geeignet. In Frankreich ist die Rammsondierung mit variabler Energie seit dem Jahr 2000 in der XP P 94-105 "Überprüfung der Verdichtungsqualität - Methode mit dynamischer Rammsondierung mit variabler Energie" genormt. Der Beitrag beschreibt das generelle Messprinzip und die Vorgehensweise zur Verdichtungskontrolle gemäß der französischen Norm. Erste positive Ergebnisse bei der Verdichtungskontrolle in Deutschland, wo die Panda-Sonde bislang vorwiegend für Eigenüberwachungsprüfungen bei Leitungsgrabenverfüllungen eingesetzt wurde, werden beispielhaft beschrieben. Schließlich werden Möglichkeiten zur Adaption in das deutsche Straßenbauregelwerk dargelegt und der hierfür noch erforderliche Forschungsbedarf erläutert.
Bogaard TA, Malet JP and Schmittbuhl J (2012), "Hydrological behaviour of unstable clay-shales slopes: the value of cross-disciplinary and multitechnological research at different scales Preface", Hydrological Processes., July, 2012. Vol. 26(14), pp. 2067-2070.
Böhm H (1966), "Die Geländeklimatische Bedeutung des Bergschattens und der Exposition für das Gefüge der Natur- und Kulturlandschaft", Erkunde. Vol. 20(2), pp. 81-93.
Abstract: The relief climatic importance of mountain shadow and aspect in the structure of the physical and cultural landscape.
Böhm R (2012), "Changes of regional climate variability in central Europe during the past 250 years", The European Physical Journal Plus. Vol. 127(54), pp. 13.
Abstract: The paper uses the data potential of very long and homogenized instrumental climate time series in the south central Europe for analyzing one feature which is very dominant in the climate change debate -whether anthropogenic climate warming causes or goes along with an increase of climate extremes. The monthly resolved data of the HISTALP data collection provide 58 single series for the three climate elements, air pressure, air temperature and precipitation, that start earlier than 1831 and extend back to 1760 in some cases. Trends and long-term low frequent climate evolution is only shortly touched in the paper. The main goal is the analysis of trends or changes of high frequent interannual and interseasonal variability. In other words, it is features like extremely hot summers, very cold winters, excessively dry or wet seasons which the study aims at. The methods used are based on detrended highpass series whose variance is analyzed in discrete 30-year windows moving over the entire instrumental period. The analysis of discrete subintervals relies on the unique number of 8 (for precipitation 7) such "normal periods". The second approach is based on the same subintervals though not in fixed but moving windows over the entire instrumental period. The first result of the study is the clear evidence that there has been no increase of variability during the past 250 years in the region. The second finding is similar but concentrates on the recent three decades which are of particular interest because they are the first 30 years with dominating anthropogenic greenhouse gas forcing. We can show that also this recent anthropogenic normal period shows no widening of the PDF (probability density function) compared to the preceding ones. The third finding is based on the moving window technique. It shows that interannual variability changes show a clear centennial oscillating structure for all three climate elements in the region. For the time being we have no explanation for this empirical evidence. We argue that it should not be an artifact of any remaining data problems, but of course a centennial cyclic effect based on 250 years of data only is not really well consolidated in terms of sample length. But it is at least an interesting new feature and the subject is open for scientific discussion and for further studies dealing with circulation effects, long-term memories in the oceans etc.
Böhm R (2009), "Geändertes Umfeld durch Klimawandel? Modified environment due to climate change?", Wildbach und Lawinenverbau. Vol. 163, pp. 34-50.
Abstract: Trotz der geforderten Kürze versucht der Artikel einen in sich konsistenten Überblick über das weite Feld der Klimavariabilität und ihrer in der Vergangenheit gegebenen und für die Zukunft zu erwartenden Trends, Pendelungen und der dahinter liegenden natürlichen und anthropogenen Ursachen zu geben. Trotz der in der öffentlichen Debatte meist betonten massiven Ausformung „des Klimawandels“ (worunter meist der von uns verursachte gemeint ist) erfordern die räumlich und zeitlich sehr variablen Wetter- und Klimaphänomene zunächst eine sehr ernsthafte Auseinandersetzung mit höchsten Qualitätsanforderungen an die Messdaten. Diesem Thema ist der erste Teil gewidmet, der Fragen der Homogenität von Klimazeitreihen diskutiert und Überlegungen über die nötige Stichprobenmächtigkeit anstellt, um zu statistisch signifikanten Aussagen zu kommen, da das „Klimasignal“ meist gut verborgen hinter „nichtklimatologischem Lärm“ ist. Erst dann wird im zweiten Kapitel „der Klimawandel“ skizziert, wobei der Fokus auf den beiden letzten Jahrhunderten, auf dem Großraum Alpen und auf dem Klimaelement Temperatur liegt. Gezeigt wird, wie stark es wann und wo, auf welche Art und Weise und warum in unserer Region wärmer geworden ist, und ob und wie stark wir daran Anteil haben. Im dritten Kapitel wird dann die Reaktion des Niederschlages auf die Erwärmung quantitativ diskutiert und auf die kleinräumig lang- und kurzfristig und auch saisonal durchaus unterschiedlichen säkularen und dekadischen Trends und Pendelungen eingegangen. Das letzte Kapitel schließlich unternimmt den Versuch, den überaus heterogenen Zukunftsaussichten näher zu kommen. Der Unterschied zwischen „Szenarien“ und „Prognosen“ wird diskutiert, die „Härte“ oder „Weiche“ der sogenannten „Fakten des Klimawandels“ werden unter die Lupe genommen und schließlich wird, trotz aller Unsicherheiten und dem diskutierten Forschungsbedarf eine abschließende Auflistung der besser und der weniger gut abschätzbaren regionalen bis lokalen Zukunftsaussichten gegeben.
Bohner A, Öhlinger R and Tomanova O (2006), "Auswirkungen der Grünlandbewirtschaftung und Flächenstilllegung auf Vegetation, Boden, mikrobielle Biomasse und Futterqualität", Die Bodenkultur. Vol. 57(1), pp. 33-45.
Abstract: A species-rich permanent meadow (Cardaminopsido halleri-Trisetetum flavescentis) with two cuts every year on a relatively nutrient-poor soil and an adjacent abandoned meadow, dominated by grasses, was investigated comparatively. The abandoned meadow was afforested with only few spruce trees (4 trees within 50 m2) and the adjacent permanent meadow was moderately fertilized with slurry. Abandonment caused within 7 years a reduction in vascular plant species richness, a decline in flowering plants, a change in plant species composition with increases in rhizomatous species, shade-tolerant species and species with low tolerance of frequent defoliation, an expansion of Festuca rubra ssp. rubra, an increase in cover value of the moss layer, a change in life forms, an increase in below-ground phytomass, an increase in root:shoot-ratio, a deeper and more uniform root distribution in the soil, a slight increase in above-ground phytomass at the time of first cut in the meadow, a reduced forage quality, and an accumulation of individual nutrients in the above-ground phytomass. In topsoil the following changes of soil chemical and microbial properties after abandonment were established: accumulation of nitrogen-poor humus, increase in C:N-ratio, slight increase in exchangeable acidity, increase in magnesium content due to bioaccumulation, and decrease in microbial biomass. Some soil physical properties were influenced positively: aggregate stability increased slightly and, because of the absence of mechanical compression by human influence, there was no soil compaction resulting in stagnant water conditions in topsoil. This later feature is typical for intensively managed grassland soils. Abandoned grasslands fulfil a sink function for atmospheric CO2, because of the gradual accumulation of nitrogen-poor humus. In addition, there is an increase in nitrogen-retention capacity of the topsoil. A low nitrogen- and potassium availability in the soil favours in early successional stage the development of Festuca rubra ssp. rubra dominated abandoned grassland on acid, deep, well-drained soils in the montane belt. This kind of abandoned grassland does not get lost immediately as agricultural area because of the inhibited growth of trees and shrubs. Abandoned meadows, dominated by grasses, are not very important for the floristic species protection and landscape aesthetics in mountainous regions.
Böhner J, Köthe R, Conrad O, Gross J, Ringeler A and Selige T (2002), "Soil Regionalisation by Means of Terrain Analysis and Process Parameterisation", In Soil Classification 2001 – European Soil Bureau – Research Report No. 7, EUR 20398 EN, Luxembourg.
Bonham-Carter G, Agterberg F and Wright D (1989), "Weights of evidence modelling: a new approach to mapping mineral potential", Statistical Applications in Earth Sciences. Vol. 89(9), pp. 171-183.
Bonnard C and Corominas J (2005), "Landslide hazard management practices in the world", Landslides., December, 2005. Vol. 2(4), pp. 245-246.
Abstract: In 1997 a Workshop on Landslide Risk Assessment organised by the IUGSWorking Group on Landslides, was held in Honolulu, Hawaii, USA. The goal of this Workshop was to provide a framework for carrying out Quantitative Risk Assessment (QRA) for landslides, to highlight its actual limitations and to disseminate the available tools for evaluating the different components of risk. Since then, the interest forQRAhas significantly increased: the InternationalConferences on Instability Planning andManagement held inVentnor,UKin 2002; the Conference on Fast SlopeMovements: Prediction and Prevention for Risk Mitigation, held in Naples, Italy in 2003; the IXth International Symposium on Landslides, held in Rio de Janeiro, Brazil in 2004; and above all the International Conference on Landslide Risk Management held in Vancouver, B.C., Canada in 2005 demonstrate such interest. Moreover, the increasing number of papers in scientific journals and books constitute excellent examples of the research activity in this fundamental topic.
Borga M, Fontana D, Da Ros D and Marchi L (1998), "Shallow landslide hazard assessment using a physically based model and digital elevation data", Environmental Geology. Vol. 35(2-3), pp. 81-88.
Abstract: A model for the analysis of topographic influence on shallow landslide initiation is applied to an experimental mountain basin where high-resolution digital elevation data are available: the Cordon catchment (5 km2) located in northern Italy. The model delineates those areas most prone to shallow landsliding due to surface topographic effects on hydrologic response. The model is composed of two parts: a steady-state model for shallow sub-surface runoff and an infinite-slope Coulomb failure model which assumes that the soil is cohesionless at failure. An inventory of landslide scars is used to document sites of instability and to provide a test of model performance by comparing observed landslide locations with model predictions. The model reproduces the observed distribution of landslide locations in a consistent way, although spatial variations in soil strength and transmissivity, which are not accounted for in the model, influence specific distribution of landslide areas within regions of similar topographic control.
Borga M, Fontana GD and Cazorzi F (2002), "Analysis of topographic and climatic control on rainfall-triggered shallow landsliding using a quasi-dynamic wetness index", Journal of Hydrology., November, 2002. Vol. 268(1-4), pp. PII S0022-1694(02)00118-X.
Abstract: A model for the prediction of both topographic and climatic control on shallow landslide initiation processes in hilly mountainous terrain is proposed. The model develops upon a theory for coupled shallow subsurface flow and landsliding of the soil mantle previously proposed by Montgomery and Dietrich [Water Resour. Res, 30 (1994) 1153], The model uses a 'quasi-dynamic' wetness index to predict the spatial distribution of soil saturation in response to a rainfall of specified duration. The rainfall predicted to cause instability in each topographic element is characterised by duration and frequency of occurrence. The incorporation of a rainfall frequency-duration relationship into assessment of landslide hazard provides a practical way to include climate information into estimation of the relative potential for shallow landsliding. The model is applied to a mountain experimental basin where high-resolution digital elevation data are available: the Cordon catchment (5 km(2)), in north-eastern Italy. An inventory of landslide scars is used to document sites of instability and to provide a test of model performance by comparing observed landslide locations with model predictions. The model reasonably reproduces the observed distribution of landslides, although spatial variability of soil properties and hydrologic complexities not accounted for by the model complicate prediction of where landslides occur within areas of similar topographic-climatic control. Model predictions from the quasi-dynamic model are compared with those provided by the steady-state model [Water Resour, Res. 30 (1994) 1153], These results suggest that the quasi-dynamic model offers significant improvement over the steady-state model in predicting existing landslides as represented in the considered landslide inventory. (C) 2002 Published by Elsevier Science B.V.
Borgatti L and Soldati M (2010), "Landslides as a geomorphological proxy for climate change: A record from the Dolomites (northern Italy)", Geomorphology., August, 2010. Vol. 120(1-2), pp. 56-64.
Abstract: This study investigates the relationships between climate changes and hillslope evolution in the Dolomites (eastern Alps, Italy), during the Late Quaternary, with particular attention paid to landslide processes. The basic premise is that modifications in landslide frequency may be interpreted as changes in the hydrological conditions of slopes, which are in turn controlled by climate. After the statistical analysis of a data set composed of 73 conventional radiocarbon ages, obtained from 24 landslides, four periods of enhanced landsliding have been identified: I. from 10,700 to 8400 cal BP, between Younger Dryas and the Preboreal: II. from 8200 to 6900 cal BP, during the older Atlantic; III. from 5800 to 4500 cal BP, between Atlantic and Subboreal; and IV. from 4000 to 2100 cal BP, between Subboreal and Subatlantic. These periods have been compared with different Lateglacial and Holocene paleoclimatic records, to check the correspondence between periods of enhanced landslide activity and cold and humid spells recognized at different spatial scales. As the records show, in the study areas, slope instability processes can be considered geomorphological indicators of climatic changes and to a certain extent reliable proxies of environmental evolution. (C) 2009 Elsevier B.V. All rights reserved.
Borgatti L and Soldati M (2005), "Geomorphological hazard and human impact in mountain environments: an introduction", Geomorphology., March, 2005. Vol. 66(1-4), pp. 7-11.
Abstract: The purpose of this Special Issue is to collect contributions presented during the Symposium of the International Association of Geomorphologists (IAG) held in Dornbirn (Vorarlberg, Austria) on 14th July 2002, where a wide international audience of researchers in the field of Applied Geomorphology convened. The IAG Symposium dealt with the Relationships between Man and the Mountain Environment in terms of Geomorphological Hazards and Human Impact in EuropeQ and was of topical importance considering the goals of the International Year of Mountains in 2002 (IYM 2002), proclaimed by the United Nations with the aim of increasing international awareness of the global importance of mountain ecosystems.
Mountain landscapes offer important perspectives and opportunities for scientific research and, in recent years, many theoretical and experimental studies have been carried out to improve our understanding of geomorphological processes in mountain environments. New methodologies and approaches have been used in facing the increased effects of extreme natural events due to natural climate variability, seismic phenomena, societal changes and human development. In fact, the need for new urban and industrial land is high in several mountain areas of the world and human settlements often develop in extremely fragile areas. In particular, the theme of natural hazards is of great concern for land management boards and the contribution of Geomorphology is relevant for the assessment and mitigation of hazards and for the definition of procedures of Environmental Impact Assessment.
Borghuis AM, Chang K and Lee HY (2007), "Comparison between automated and manual mapping of typhoon-triggered landslides from SPOT-5 imagery", International Journal of Remote Sensing., April, 2007. Vol. 28(7-8), pp. 1843-1856.
Abstract: Two large tropical cyclones struck Taiwan in the summer of 2004 and landslides triggered by these events caused not only casualties and housing damage but also produced large volumes of sediment that entered rivers and reservoirs. For reservoir and watershed management it is important to quickly identify the location and areal extent of new landslides for coordinating mitigation efforts. In this study, two automated methods, supervised and unsupervised classification of 10 m multi-spectral SPOT-5 imagery, were tested for their ability to identify and map landslide areas before and after the two storm events. A slope map was applied to mask roads, riverbeds and agricultural fields erroneously commissioned as landslides. The automated classification results were compared with manually delineated landslides using SPOT-5 supermode satellite imagery with a resolution of 2.5 m. Statistical testing and spatial analysis of the mapping results were performed. Finally, the results from all three methods were validated by using 0.35 m orthophotographs. This paper reports the results and discusses the salient differences between the automated and manual methods.
Borter P (1999), "Risikoanalyse bei gravitativen Naturgefahren - Fallbeispiele und Daten", In Umweltmaterialien, Nr. 107/II. , pp. 129. Bundesamt für Umwelt, Wald und Landschaft.
Borter P (1999), "Risikoanalyse bei gravitativen Naturgefahren - Methode", In Umweltmaterialien, Nr. 107/I. , pp. 115. Bundesamt für Umwelt, Wald und Landschaft.
Bovolo CI and Bathurst JC (2012), "Modelling catchment-scale shallow landslide occurrence and sediment yield as a function of rainfall return period", Hydrological Processes., February, 2012. Vol. 26(4), pp. 579-596.
Abstract: A model-based method is proposed for improving upon existing threshold relationships which define the rainfall conditions for triggering shallow landslides but do not allow the magnitude of landsliding (i.e. the number of landslides) to be determined. The SHETRAN catchment-scale shallow landslide model is used to quantify the magnitude of landsliding as a function of rainfall return period, for focus sites of 180 and 45 km2 in the Italian Southern Alps and the central Spanish Pyrenees. Rainfall events with intensities of different return period are generated for a range of durations (1-day to 5-day) and applied to the model to give the number of landslides triggered and the resulting sediment yield for each event. For a given event duration, simulated numbers of landslides become progressively less sensitive to return period as return period increases. Similarly, for an event of given return period, landslide magnitude becomes less sensitive to event duration as duration increases. The temporal distribution of rainfall within an event is shown to have a significant impact on the number of landslides and the timing of their occurrence. The contribution of shallow landsliding to catchment sediment yield is similarly quantified as a function of the rainfall characteristics. Rainfall intensityduration curves are presented which define different levels of landsliding magnitude and which advance our predictive capability beyond, but are generally consistent with, published threshold curves. The magnitude curves are relevant to the development of guidelines for landslide hazard assessment and forecasting. Copyright (c) 2011 John Wiley & Sons, Ltd.
Bozzano F, Martino S, Prestininzi A, Scarascia Mugnozza G, Bianchi Fasani G, Esposito C and Manuel M (2004), "An example of earthquake triggered landslide in structurally complex formations", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 1133-1139. Taylor & Francis.
Abstract: The 31st, October 2002 Molise (Central Italy) earthquake (MI 5.4) triggered an earthslide which involved scaly clay shales. Based on site investigation and borehole data it was possible to define the ground crack pattern and the slope movement kinematics; the inferred maximum depth of the sliding surface is about 50 in b.g.I., indicating an estimatcd involved volume up to 40. 106 m3. The coseismic increase in pore water pressure is clearly shown by the presence of sand-mud boils in the main scarp area and the delayed movement can be referred to transient flow conditions within the landslide mass. In the preliminary laboratory tests it was considered the influence of groundwater chemical composition on the physical and mechanical properties of the considered scaly clays.
Brardinoni F, Slaymakerl O and Hassan MA (2003), "Landslide inventory in a rugged forested watershed: a comparison between air-photo and field survey data", Geomorphology., September, 2003. Vol. 54(3-4), pp. 179-196.
Abstract: Landslide inventories are routinely compiled by means of aerial photo interpretation (API). When examining photo pairs, the forest canopy (notably in old-growth forest) hides a population of "not visible" landslides. In the present study, we attempt to estimate how important is the contribution of landslides not detectable from aerial photographs to the global mass of sediment production from mass failures on forested terrain of the Capilano basin, coastal British Columbia. API was coupled with intensive fieldwork for identification and measurement of all landslides. A 30-year framework was adopted. We show that "not visible" landslides can represent up to 85% of the total number of failures and account for 30% of the volume of debris mobilised. Such percentages display high sub-basin variability with rates of sediment production varying by one order of magnitude between two sub-basins of the study area. This is explained qualitatively by GIS-based analysis of slope frequency distributions, drainage density, and spatial distribution of surficial materials. Such observations find further support in the definitions of transport-limited and supply-limited basins. As a practical consideration to land managers, we envisage that supplementary fieldwork for landslide identification is mandatory in transport-limited systems only. Fieldwork has demonstrated that gully-related failures have a greater importance than one could expect from API. (C) 2002 Elsevier Science B.V. All rights reserved.
Brenning A (2005), "Spatial prediction models for landslide hazards: review, comparison and evaluation", Natural Hazards and Earth System Sciences. Vol. 5(6), pp. 853-862. European Geosciences Union.
Abstract: The predictive power of logistic regression, support vector machines and bootstrap-aggregated classification trees (bagging, double-bagging) is compared using misclassification error rates on independent test data sets. Based on a resampling approach that takes into account spatial autocorrelation, error rates for predicting "present" and "future" landslides are estimated within and outside the training area. In a case study from the Ecuadorian Andes, logistic regression with stepwise backward variable selection yields lowest error rates and demonstrates the best generalization capabilities. The evaluation outside the training area reveals that tree-based methods tend to overfit the data.
Breuss G and Wanner G (1980), "Laternsertal: Geschichte, Wirtschaft, Volkskunde" Rheticus-Gesellschaft, Feldkirch..
Broll G, Hiller B, Bednorz F, Muller G and Reineke T (2005), "Guideline for describing soil profiles in mountain ecosystems", Mountain Ecosystems: Studies In Treeline Ecology. , pp. 1-42.
Abstract: This guideline for describing soil profiles in mountainous ecosystems is intended to provide scientists around the world with other than soil science expertise to collect useful soil data such as soil profile descriptions and soil sampling. From the collected soil profile descriptions the scientists should be able to calculate important parameters such as field capacities. In addition, the main objective of this guideline is to streamline methods for soil data collection in mountainous terrain throughout the world, which would result in comparable soil data. The field book Schoeneberger et al. (2002) is recommended as basis for the guideline. This manual was used providing a minimum data set for de scripting soil profiles in mountainous areas. Before describing a soil profile a representative site should be selected. A representative site is defined by the objective of the study. This could consist of parameters such as vegetation communities, microtopography etc. Only those parameters have to be considered, which are essential for a minimum data set. We tried to focus on the specific site conditions in mountainous areas with great heterogeneity in many ways and added special recommendations for their description and sampling. We focussed on those soil parameters, which are necessary to investigate ecological processes, like interactions between plants and soil. In this manual we do not consider genetic purposes. Interpretation of pedogenesis as well as soil mapping should be done in cooperation with soil scientists only. In connection with soil profile description some data, e. g. texture and slope gradient, are collected, which are necessary for erosion risk assessment. Examples of soil profile descriptions in alpine areas of Europe and Asia are given in order to improve the clarity of the guideline.
Bromhead EN (2004), "Landslide slip surfaces: their origins, behaviour and geometry", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 523-602. Taylor & Francis.
Abstract: The devclopment and subsequent behaviour of slip surfaces, from "first time" failures through to their long term behaviour in old landslides in an established and ongoing research topic. Recent work suggests that short term and long tcrm changes in slip surfaces may alter their behaviour when inactive landslides are stationary, and which have the potential to affect landslide reactivation. The behaviour of slip surfaces is inseparable from the behaviour of pore fluids in the soil mass, and attention is given to this aspect in the paper. 2-D and 3-D analysis of landslides is considered, and some insights into the treatment of the double curvature of slip surfaces, and how this affects the way they are analysed is offered.
Brooks SM, Crozier MJ, Glade TW and Anderson MG (2004), "Towards establishing climatic thresholds for slope instability: Use of a physically-based combined soil hydrology-slope stability model", Pure and Applied Geophysics., March, 2004. Vol. 161(4), pp. 881-905.
Abstract: Shallow landslides are often linked to high magnitude rainstorms. Research has attempted to establish threshold rainfall totals that trigger shallow landslides, based mainly on field evidence. Complications arise because not all regolith has the same hydrological behaviour, and research frequently fails to take this into account. This paper uses a combination of field and modelling approaches to explore the triggering rainfall thresholds for shallow failures in deforested hill country of New Zealand. It emphasises the role of variations in regolith hydrology, focussing on unsaturated and saturated zone responses. By using a modelling approach, detailed variations in pore pressure (positive and negative) responses are investigated, developing ideas initially derived from field evidence. This paper defines and develops earlier research that establishes values for maximum and minimum probability thresholds for shallow landslides, and provides a more generalised model that can be applied more widely. Hydrological mechanisms for shallow landslides are investigated in greater detail than previously possible using a Combined Hydrology And Stability Model (CHASM(TM)).
Brooks SM, Crozier MJ, Preston NJ and Anderson MG (2002), "Regolith stripping and the control of shallow translational hillslope failure: application of a two-dimensional coupled soil hydrology-slope stability model, Hawke's Bay, New Zealand", Geomorphology., June, 2002. Vol. 45(3-4), pp. PII S0169-555X(01)00153-2.
Abstract: Rainfall-triggered regolith landslides constitute a dominant erosional process in New Zealand hill country. Conversion of forest to pasture about 150 years ago decreased the size of event required to trigger slope failure resulting in greater landslide activity. Recent research indicates that shallow landslides then cause progressive regolith stripping with redeposition at the slope base. The exposed bedrock is less permeable than the pre-existing regolith cover and the redeposited soil has a higher unit weight. Hence, alterations in both hydrological and geotechnical conditions result, changing the triggering thresholds for further failure. In this paper three phases of regolith stripping are investigated using a process-based model, to define variations in both the triggering storms as well as the failure mechanisms under these altered hydrological and geotechnical conditions. Over time, as the regolith is stripped progressively upslope, the threshold for slope failure also changes such that the landscape becomes more stable. However, there is a varying sensitivity to storm type for each of the three phases, which adds complexity to the relationship between regolith stripping and slope failure. Model results suggest different hydrological conditions for slope instability, depending on the degree of stripping and redeposition, adding further complexity. Future advances in process-based modelling are required for detailed investigation of temporal changes in landscape susceptibility to slope failure, and uncertainty in both model parameterisation as well as process representation should be emphasised when applying such models to the long term. (C) 2002 Elsevier Science B.V. All rights reserved.
Broothaerts N, Kissi E, Poesen J, Van Rompaey A, Getahun K, Van Ranst E and Diels J (2012), "Spatial patterns, causes and consequences of landslides in the Gilgel Gibe catchment, SW Ethiopia", Catena., October, 2012. Vol. 97, pp. 127-136.
Abstract: The Gilgel Gibe catchment in SW Ethiopia is one of the areas in East Africa affected by landslides. To better understand the patterns and the causal factors of these landslides, all landslides in a small study area (14 km(2)) in the hilly parts of the Gilgel Gibe catchment were mapped and analyzed. In total, 60 landslides were mapped. These landslides caused a displacement of 1 million m(3) slope material, which corresponds to a mean displaced volume of 50 ton ha(-1) y(-1) the last 20 years. Moreover many landslides deliver directly sediment to the rivers and hence increase the sediment load in the rivers. This soil loss to the rivers was estimated at 11 ton ha(-1) y(-1) during the same period. High annual rainfall (ca. 2000 mm y(-1)), lithological and pedological properties and to a lesser extent steep (> 16 degrees) slopes turn the area into an inherent unstable situation and can be indicated as preconditions for the landslides in the study area. Distance to rivers is significantly the most important precondition, as slopes near rivers are less stable than slopes further away from the rivers. This is mainly caused by river incision and bank erosion which often occur in the area and which can be attributed to increased runoff due to deforestation over the past 20 years. Therefore recent deforestation caused more shallow landslides but also indirectly more deep-seated landslides close to the rivers. Heavy rainfall is indicated as the main triggering factor for almost all landslides. (c) 2012 Elsevier B.V. All rights reserved.
Bründl M (2009), "Risikokonzept für Naturgefahren - Leitfaden. Testversion Februar 2009" Bern Nationale Plattform für Naturgefahren (PLANAT).
Brunetti M, Buffoni L, Maugeri M and Nanni T (2000), "Precipitation intensity trends in Northern Italy", International Journal of Climatology. Vol. 20, pp. 1017-1031.
Abstract: Recent studies on changes in precipitation intensity encompassing North America have found evidence for an increase in the relative amount of precipitation contributed by heavy and extreme rainfall events in the last 80 years. Within this context, the purpose of this paper is to verify whether such a signal can also be detected in northern Italy, where daily precipitation data are available from the beginning of the 19th century. The analysis is performed by applying the non-parametric Mann-Kendall test to mean anomaly series obtained through averaging the anomalies of some precipitation intensity statistics over five stations: Genoa (1833-1998), Milan (1858-1998), Mantova (1868-1997), Bologna (1879-1998) and Ferrara (1879-1996). It provides evidence that in northern Italy, the number of rainy days has a stronger and more significant negative trend than the corresponding precipitation amount, both on a yearly basis and in all of the seasons. As a consequence, precipitation intensity has a positive trend. The increase in precipitation intensity causes a significant positive trend in the proportion of total precipitation contributed by heavy precipitation events (i.e. daily precipitation > 25 mm and daily precipitation > 50 mm). The trend is mainly caused by the last 60-80 years, and is particularly evident in the periods of 1930-1945 and 1975-1995. The increase in precipitation intensity is connected to a modification of the distribution of daily precipitation values in a year, with trends that grow from the lower to the upper percentiles, and up to 4 mm/100 years for the 95th percentile. Copyright (C) 2000 Royal Meteorological Society.
Brunetti MT, Peruccacci S, Rossi M, Luciani S, Valigi D and Guzzetti F (2010), "Rainfall thresholds for the possible occurrence of landslides in Italy", Natural Hazards and Earth System Sciences. Vol. 10(3), pp. 447-458.
Abstract: In Italy, rainfall is the primary trigger of landslides that frequently cause fatalities and large economic damage. Using a variety of information sources, we have compiled a catalogue listing 753 rainfall events that have resulted in landslides in Italy. For each event in the catalogue, the exact or approximate location of the landslide and the time or period of initiation of the slope failure is known, together with information on the rainfall duration D, and the rainfall mean intensity I, that have resulted in the slope failure. The catalogue represents the single largest collection of information on rainfall-induced landslides in Italy, and was exploited to determine the minimum rainfall conditions necessary for landslide occurrence in Italy, and in the Abruzzo Region, central Italy. For the purpose, new national rainfall thresholds for Italy and new regional rainfall thresholds for the Abruzzo Region were established, using two independent statistical methods, including a Bayesian inference method and a new Frequentist approach. The two methods proved complementary, with the Bayesian method more suited to analyze small data sets, and the Frequentist method performing better when applied to large data sets. The new regional thresholds for the Abruzzo Region are lower than the new national thresholds for Italy, and lower than the regional thresholds proposed in the literature for the Piedmont and Lombardy Regions in northern Italy, and for the Campania Region in southern Italy. This is important, because it shows that landslides in Italy can be triggered by less severe rainfall conditions than previously recognized. The Frequentist method experimented in this work allows for the definition of multiple minimum rainfall thresholds, each based on a different exceedance probability level. This makes the thresholds suited for the design of probabilistic schemes for the prediction of rainfall-induced landslides. A scheme based on four probabilistic thresholds is proposed. The four thresholds separate five fields, each characterized by different rainfall intensity-duration conditions, and corresponding different probability of possible landslide occurrence. The scheme can be implemented in landslide warning systems that operate on rainfall thresholds, and on precipitation measurements or forecasts.
Brunsden D and Ibsen M (1996), "Landslide recognition. Identification, Movement and Causes" Chichester , pp. 103-119. Wiley.
Buchli C and Abderhalden W (1999), "Einwirkungen des Alpensteinbocks (Capra i. ibex) auf alpine Rasen", Zeitschrift für Jagdwissenschaft. Vol. 45(2), pp. 77-87.
Abstract: Unter dem Begriff Erosion wird im allgemeinen der Bodenabtrag infolge Wasser, Wind Schneebewegungen oder- in sehr steilen Gebieten- auch durch die Schwerkraft verstanden. In der folgenden Untersuchung im Rahmen des Steinbockprojektes Albris/Schweizerischer Nationalpark (BUCHLI und ABDERHALDEN, 1998) wird dlese Definition um die Möglichkeit erweitert, dass Tiere die Erosion in einem Gebiet beschleunigen können, sei es durch Verhinderung der Pflanzendecke infolge Beäsung oder durch Tritteinwirkung sowie Liegeplätze an bevorzugter Lage. Von edichen Tierarten wie Rothirsch, Steinbock, aber auch Schaf und Ziege, ist bekannt, daft sie gerne an vegetationslosen Stellen liegen, was die Wiederbegrünung dieser Stellen verzögern oder ganz verhindern kann.
Buck BJ and Monger HC (1999), "Stable isotopes and soil-geomorphology as indicators of Holocene climate change, northern Chihuahuan Desert", Journal of Arid Environments., December, 1999. Vol. 43(4), pp. 357-373.
Abstract: Coeval delta(13)C Shifts recorded in buried soils at both piedmont slope and basin floor sites in the northern Chihuahuan Desert indicate a major shift from C(4) grasses to C(3) desert-scrub between 7 and 9 ka. The age assignments are based on stratigraphic correlations to charcoal dates and carbon-14 dates of carbonate. This shift is synchronous with a period of cooling in the North Atlantic that: may have triggered a period of drought in the south-western United States. Coinciding with this vegetation change, geomorphic evidence in Rio Grande, piedmont, and basin floor eolian environments indicates a major period of erosion. Subsequent gradual enrichment of pedogenic carbonate delta(13)C values in younger deposits suggests that C(4) grasses rebounded in the late Holocene (approximately 4 ka), which is consistent with other evidence of increased moisture regionally. A period of less severe aridity at approximately 2.2 ka is indicated by erosion and subsequent deposition along the alluvial fans and within the basin, and correlates with depleted pedogenic carbonate delta(13)C values suggesting a decrease in C(4) grasses. Isotope and packrat midden records should be used together to infer past environmental conditions at different elevations. (C) 1999 Academic Press.
Bucknam R, Coe J, Chavarría M, Godt J, Tarr A, Bradley L, Rafferty S, Hancock D, Dart R and Johnson M (2001), "Landslides triggered by Hurricane Mitch in Guatemala – Inventory and discussion. U.S. Geological Survey Open-File Report 01-443."
Bui DT, Pradhan B, Lofman O and Revhaug I (2012), "Landslide Susceptibility Assessment in Vietnam Using Support Vector Machines, Decision Tree, and Naive Bayes Models", Mathematical Problems In Engineering. , pp. 974638.
Abstract: The objective of this study is to investigate and compare the results of three data mining approaches, the support vector machines (SVM), decision tree (DT), and Naive Bayes (NB) models for spatial prediction of landslide hazards in the Hoa Binh province (Vietnam). First, a landslide inventory map showing the locations of 118 landslides was constructed from various sources. The landslide inventory was then randomly partitioned into 70% for training the models and 30% for the model validation. Second, ten landslide conditioning factors were selected (i.e., slope angle, slope aspect, relief amplitude, lithology, soil type, land use, distance to roads, distance to rivers, distance to faults, and rainfall). Using these factors, landslide susceptibility indexes were calculated using SVM, DT, and NB models. Finally, landslide locations that were not used in the training phase were used to validate and compare the landslide susceptibility maps. The validation results show that the models derived using SVM have the highest prediction capability. The model derived using DT has the lowest prediction capability. Compared to the logistic regression model, the prediction capability of the SVM models is slightly better. The prediction capability of the DT and NB models is lower.
Bui DT, Pradhan B, Lofman O, Revhaug I and Dick OB (2012), "Landslide susceptibility assessment in the Hoa Binh province of Vietnam: A comparison of the Levenberg-Marquardt and Bayesian regularized neural networks", Geomorphology., October, 2012. Vol. 171, pp. 12-29.
Abstract: This study investigates the potential application of artificial neural networks in landslide susceptibility mapping in the Hoa Binh province of Vietnam. A landslide inventory map of the study area was prepared by combining landslide locations investigated through three projects during the last 10 years. Some recent landslide locations were identified based on SPOT satellite images, field surveys, and existing literature. The images have a spatial resolution of 2.5 m. Ten landslide conditioning factors were utilized in the multilayer feed-forward neural network analysis: slope, aspect, relief amplitude, lithology, land use, soil type, rainfall, distance to roads, distance to rivers and distance to faults. Two back-propagation training algorithms, Levenberg-Marquardt and Bayesian regularization, were utilized to determine synoptic weights using a training dataset. Relative importance of each landslide conditioning factor was assessed using the above mentioned synoptic weights. The final connection weights obtained in the training phase were applied to the entire study area to produce landslide susceptibility indexes. The results were then imported to a GIS and landslide susceptibility maps were constructed. landslide locations not used in the training phase were used to verify and compare the results of the landslide susceptibility maps. Finally, the two landslide susceptibility maps were validated using the prediction-rate method. Subsequently, areas under the prediction curves were assessed. The prediction accuracy of landslide susceptibility maps produced by the Bayesian regularization neural network and the Levenberg-Marquardt neural network were 90.3% and 86.1% respectively. These results indicate that the two models seem to have good predictive capability. The Bayesian regularization network model appears more robust and efficient than the Levenberg-Marquardt network model for landslide susceptibility mapping. (C) 2012 Elsevier B.V. All rights reserved.
Bui DT, Pradhan B, Lofman O, Revhaug I and Dick OB (2012), "Spatial prediction of landslide hazards in Hoa Binh province (Vietnam): A comparative assessment of the efficacy of evidential belief functions and fuzzy logic models", Catena., September, 2012. Vol. 96, pp. 28-40.
Abstract: The main objective of this study is to evaluate and compare the results of evidential belief functions and fuzzy logic models for spatial prediction of landslide hazards in the Hoa Binh province of Vietnam, using geographic information systems. First, a landslide inventory map showing the locations of 118 landslides that have occurred during the last ten years was constructed using data from various sources. Then, the landslide inventory Was randomly partitioned into training and validation datasets (70% of the known landslide locations were used for training and building the landslide models and the remaining 30% for the model validation). Secondly, nine landslide conditioning factors were selected (i.e., slope, aspect, relief amplitude, lithology, landuse, soil type, distance to roads, distance to rivers and distance to faults). Using these factors, landslide susceptibility index values were calculated using evidential belief functions and fuzzy logic models. Finally, landslide susceptibility maps were validated and compared using the validation dataset that was not used in the model building. The prediction-rate curves and area under the curves were calculated to assess prediction capability. The results show that all the models have good prediction capabilities. The model derived using evidential belief functions has the highest prediction capability. The model derived using fuzzy SUM has the lowest prediction capability. The fuzzy PRODUCT and fuzzy GAMMA models have almost the same prediction capabilities. In general, all the models yield reasonable results that may be used for preliminary landuse planning purposes. (C) 2012 Elsevier B.V. All rights reserved.
Bunza G (1976), "Geologisch-morphologische Grundlagen der Wildbachkunde" Vol. 11, pp. 1-86. Bayerische Landesstelle für Gewässerkunde.
Bunza G (1978), "Ökologische Analysen von Almflächen im Gasteinertal. Veröff. der Österr. MaB - Hochgebirgsprogramm Hohe Tauern" Innsbruck Vol. 2, pp. 315-334. Universitätsverlag Wagner.
Abstract: Comparative measurements of runoff and soll erosion on alpine pastures at the Stubnerkogel in the valley of Gastein.
On three slopes of a non cultivated alpine pasture at the Stubnerkogel in Badgastein the relationship between runoff and soil erosion and vegetation and geology were studied under simulated rainstorm experiments. In cooperation with the institute for general botany at the university of Innsbruck (Prof. Dr. A. CERNUSCA) a transportable spray-irrigation installation by KARL and TOLDRIAN (1973) of the Bavarian national office for watermanagement was used.
The subsoil of the sprinkled areas, which covered 100 m² respective, consists of local moraine gravel originated from granit-gneisses and mica schists. The grown soil is a silty fine grained sand with tighty stratification, with a high soil moisture and a minimal fraction of effective size of grains (silt and clay). The slopes differed mainly in their vegetation and soil structure. The duration of rainfall was one hour at times; the intensities of rainiall were 80 mm (slope I), 55 mm (slope 2), 83 mm (slope 3). On test area number 1 with an inclination of 40 to 45 %, a thick vegetation cover of subalpine grass associations hindered a greater runoff and a soil erosion. Due to an impermeable layer 2185 l water (27,3 %) ran off yet.
A thick plant formation with green aider (Alnus viridis) on test area number 2 effected the late beginning of tbe surface nmoff. In spite of the greatest inclination with 80 % only 900 l water (16,4 %) ran off. No soil erosion was observed.
A short time after the start of raining on test area number 3, which was bare of a vegetation cover (slope inclination 35 to 40 %), appeared a surface closing by mica plates. This advanced the surface runoff, which was 2030 l (32,2 %) and hindered the soil erosion.
The rates of surface runoff which were observed fluctuate in the order of magnitudes of the prevaillng spray irrigation tests in the Bavarian Alps. Nevertheless this three tests can only be considered as a location investigation. By a larger grown over with green alder and dwarf shrubs the soil structure of such an alpine pasture will be meliorated, the surface runoff will become smaller and the soil erosion will be small further on.
Bunza G (1992), "Instabile Hangflanken und ihre Bedeutung für die Wildbachkunde" Deutscher Alpenverein.
Bunza G (1992), "Die Erfassung des aktuellen Abtragsgeschehens mit Hilfe geomorphologischer Kartierungen zur Beurteilung von potentiellen Gefahrenräumen", In Proc. of the VII International Congress Interpraevent 1992, Bern. Bern Vol. 6, pp. 213-236.
Bunza G (1982), "Oberflächenabfluss und Bodenabtrag in alpinen Graslandökosystemen", Verhandlungen der Gesellschaft für Ökologie. Vol. 12, pp. 101-109.
Bunza G and Christa R (1980), "Zur Frage der Beeinflussung des Bodenabtrags durch Schneefeldsprengungen in den bayerischen Alpen", In Proc. of the IV International Congress Interpraevent 1980, Bad Ischl. Bad Ischl Vol. 2, pp. 309-314.
Bunza G, Deisenhofer E, Karl J, Porzelt M and Riedl J (1985), "Der künstliche Starkniederschlag der transportablen Beregnungsanlage", DVWK. Vol. 71, pp. 3-35.
Bunza G, Jürging P, Löhmannsröben R, Schauer T and Ziegler R (1996), "Abfluss und Abtragsprozesse in Wildbacheinzugsgebieten – Grundlagen zum integralen Wildbachschutz", Schriftenreihe des Bayerischen Landesamtes für Wasserwirtschaft. Vol. 27, pp. 89.
Bunza G, Karl J and Mangelsdorf J (1976), "Geologisch-morphologische Grundlagen der Wildbachkunde" Vol. 11, pp. 129. Bayerische Landesstelle für Gewässerkunde.
Bunza G, Löhmanssröben R and Schauer T (1992), "Erfassung und Darstellung des Gefährdungspotentials durch Oberflächenabfluss und Abtrag in einem Wildbacheinzugsgebiet (Hirschbach / Hindelang)", In Proc. of the VII International Congress Interpraevent 1992, Bern. Bern Vol. 6, pp. 273-276.
Bunza G and Schauer T (1989), "Der Einfluss von Vegetation, Geologie und Nutzung auf den Oberflächenabfluss bei künstlichen Starkregen in den Wildbacheinzugsgebieten der Bayer. Alpen", In Grundlagen des Wasserbaues, Aktuelle Beiträge. Informationsberichte Bayer. Landesamtes für Wasserwirtschaft Nr. 2.
Bürkle J and Kuntsche K (2005), "Bodenmechanische Untersuchungen an einem Rutschungshang in Rheinhessen", In 15. Tagung für Ingenieurgeologie. Erlangen
Abstract: Im Zuge eines interdisziplinären Forschungsprojektes wurden bodenmechanische Untersuchungen am Jakobsberg bei Ockenheim (Rheinhessen) durchgeführt. Hierzu wurden sowohl im Hangbereich als auch im Hinterland bei bis zu 80 m tiefen Kernbohrungen möglichst ungestörte Proben aus den anstehenden tertiären Tonen entnommen und bodenmechanischen Laborversuchen unterzogen. Anhand einer Zuordnung von Bohrkernen aufgrund bodenmechanischer, mineralogischer und auch feinstratigrafischer Untersuchungen wurden die mechanischen Eigenschaften der Böden aus dem Rutschhang mit stratigrafisch identischen Schichten im bislang von der Hangbildung unbeeinflussten Hinterland verglichen. Aus diesem Vergleich werden Schlüsse gezogen, welche die Ausbildung von immer neuen Rutschungen an Rheinhessens Hängen erklären können. Es ist nach den Ergebnissen dieser Untersuchungen zu erwarten, dass das Risiko künftiger Rutschungen genauer eingeschätzt werden kann.
Burri K (2006), "Boden-Aggregatstabilität als Parameter zur Quantifizierung von Vegetationseffekten auf oberflächennahe Bodenbewegungen". Thesis at: ETH Zürich.
Burton A, Arkell TJ and Bathurst JC (1998), "Field variability of landslide model parameters", Environmental Geology., August, 1998. Vol. 35(2-3), pp. 100-114.
Abstract: A data set of parameters (slope, soil depth and soil shear strength) relevant to spatially distributed modelling of shallow landslides triggered by rain and snowmelt events was determined from field measurements in 250 grid elements of dimensions 25 m (downslope) x 10 m (across slope) in an area of 250 m x 250 m on a hillslope in Scotland. These data provide an unusually detailed basis for the evaluation of spatial variability and uncertainty in model parameterisation. The variations in slope and soil strength are represented adequately by normal distributions; a Weibull distribution is suggested for the soil depth data. The factor of safety calculated at each point in the grid was shown partially to identify observed landslides, with a number of false predictions of occurrence. Trend analysis and semivariogram analysis of the data set suggest that the use of kriging could improve upon this approach to landslide prediction by providing areal estimates of parameters at the grid element scale with associated error bounds.
Burton A and Bathurst JC (1998), "Physically based modelling of shallow landslide sediment yield at a catchment scale", Environmental Geology., August, 1998. Vol. 35(2-3), pp. 89-99. Springer Verlag.
Abstract: A shallow landslide erosion and sediment yield component, applicable at the basin scale, has been incorporated into the physically based, spatially distributed, hydrological and sediment transport modelling system, SHETRAN. The component determines when and where landslides occur in a basin in response to time-varying rainfall and snowmelt, the volume of material eroded and released for onward transport, and the impact on basin sediment yield. Derived relationships are used to link the SHETRAN grid resolution (up to 1 km), at which the basin hydrology and final sediment yield is modelled, to a subgrid resolution (typically around 10-100 m) at which landslide occurrence and erosion is modelled. The subgrid discretization, landslide susceptibility and potential landslide impact are determined in advance using a geographic information system (GIS), with SHETRAN then providing information on temporal variation in the factors controlling landsliding. The ability to simulate landslide sediment yield is demonstrated by a hypothetical application based on a catchment in Scotland.
Buscarnera G and di Prisco C (2013), "Soil stability and flow slides in unsaturated shallow slopes: can saturation events trigger liquefaction processes?", Géotechnique. Vol. 63, pp. 801-817. Ice Virtual Library.
Abstract: This paper illustrates an application of the theory of material stability to the analysis of unsaturated slopes. The main goal is to contribute to the understanding of rainfall-induced flow slides. For this purpose, a coupled hydromechanical constitutive model is combined with a simplified approach for the analysis of infinite slopes. Simple shear-test simulations are used to evaluate triggering perturbations and investigate the role of both initial suction and stress anisotropy in the activation of slope failures. The numerical simulations clearly show that different mechanisms of activation can be originated. The onset of instability is detected by introducing appropriate stability indices for distinct modes of failure: localised shear failure, static liquefaction and wetting-induced collapse. Critical intervals of slope inclinations are identified, cautioning that the predicted failure mode may change dramatically depending on initial conditions, slope angle and material properties. The numerical simulations demonstrate that, in particular circumstances, saturation of the pore space can be the unexpected result of a volumetric instability. According to this interpretation, a rainfall-induced flow slide can originate from a complex chain process consisting of a sudden volume collapse, uncontrolled saturation of the pores and, eventually, catastrophic liquefaction of the deposit.
Buscarnera G and di Prisco C (2011), "Stability criteria for unsaturated shallow slopes", Géotechnique Letters. Vol. 1, pp. 85-90(5).
Abstract: This letter focuses on the mechanical conditions governing the initiation of landslides in unsaturated shallow slopes. The goal is to provide mathematical criteria for predicting the onset of slope instabilities and capturing the interplay between saturation conditions and shear failure. For this purpose, the standard scheme of infinite slope is used and the mechanical response of the deposit is represented through simple shear kinematics. This assumption enables the study of different perturbation scenarios using a modelling strategy that: (i) incorporates the constraints describing the interaction with the pore fluids into the control conditions and (ii) allows the analytical derivation of stability indices for each scenario. The theoretical results show that, in unsaturated slopes, the coupling between the solid skeleton and the pore fluid can exacerbate the tendency to undergo mechanical instabilities. This general aspect is clearly disclosed by the analytical expression of the stability index for water-undrained shearing. It is found that, because of hydro-mechanical coupling, the failure mode originated by these perturbations embodies some characteristics of both shear localisation and static liquefaction. As a result, depending on soil properties and initial conditions, the unstable response resulting from its activation can resemble either phenomena and predictive models are necessary to distinguish between the two scenarios.
Buscombe D (2008), "Estimation of grain-size distributions and associated parameters from digital images of sediment", Sedimentary Geology., October, 2008. Vol. 210(1-2), pp. 1-10.
Abstract: A new technique to estimate the grain-size distribution (GSD) from a digital image of sediment is proposed, advancing the applicability of a suite of sedimentary 'look-up-catalogue' approaches originated by Rubin [Rubin, D.M., 2004. A simple autocorrelation algorithm for determining grain size from digital images of sediment. journal of Sedimentary Research, 74(1): 160-165]. The outputs of an automated procedure to estimate the GSD from digital images of sediment are examined with reference to the distributions obtained from both manually sieving the corresponding sediment samples, and axial measurements made on the grains in the images. Measures of grain-size obtained from the imaging procedure correlate very well with grain-size measures derived from both the number-frequency and mass-frequency curve. As expected the GSD obtained from the new automated approach, based on kernel density, compared better with point counts because of a shared two-rather than three-dimensionality. The GSD shape is not always mimicked exactly, however the percentiles obtained from the cumulative GSD compare well with those from sieved distributions, which allow for the first time computation of graphical sorting and skewness from digital images of sediment which are accurate reflections of those measures obtained for point-count and sieved samples. The new approach allows for realistic GSDs from which the residual can be computed, thus a numerical criterion upon which the grain-size distribution from an image can be accepted or rejected. Finally, a method is presented whereby two-dimensional autocorrelogram fields are derived from image power spectra. Ellipsoids are fitted to isolines of autocorrelation coefficients, and from this the dominant axial lengths and orientation of these isolines which could facilitate computation of major and minor axis lengths of grains in sample images, as well as their dominant orientation. In turn, this could allow for parameterisation of axial ratios for parameterisation of 2D shape. Such analysis is completely automated, rapid and non-intrusive. (C) 2008 Elsevier B.V. All rights reserved.
Butler JB, Lane SN and Chandler JH (2001), "Automated extraction of grain-size data from gravel surfaces using digital image processing", Journal of Hydraulic Research. Vol. 39(5), pp. 519-529.
Abstract: This paper describes and tests a method for the automated extraction of grain-size data from digital imagery. It combines two basic image processing methods for this purpose: grey-scale thresholding to create a binary image and watershed segmentation to grow edges on the binary image to allow the identification of individual grains. The method is subject to rigorous testing in terms of edge detection and automatic measurement of grain-size information from the edge images, and is also compared with the results obtained from simple direct clast sampling. The edge detection methods are tested with respect to manually-identified edges. This suggests that simple thresholding of raw imagery produces grain-size estimates that are: (i) in excellent agreement with manual estimates, above a critical particle size defined by the scale of the photography; (ii) downgraded with the inclusion of additional edge information from analysis of high resolution digital elevation models (DEMs); and (iii) not affected by the use of raw imagery as opposed to imagery that has been rectified to deal with geometric, tilt and relief distortion effects. The automated ellipse-based measurement method is shown to produce a good estimate of two-dimensional a- and b- axes as they appear as long and short axes on the edge images. Thus, the research shows that it can be used to map and quantify very rapidly spatial variations in grain-size characteristics, although it cannot deal with the long-recognised problem of the relationship between two-dimensional planform grain-size estimates and actual a- and b- axes obtained by direct grain sampling.
BWG (2002), "Hochwasser 2000 - Ereignisanalyse/Fallbeispiele. Berichte des BWG, Serie Wasser: 2" Bern
Caine N (1980), "The Rainfall Intensity - Duration Control of Shallow Landslides and Debris Flows", Geografiska Annaler Series A-physical Geography. Vol. 62(1-2), pp. 23-27.
Cala M, Flisiak J and Tajdus A (2004), "Slope stability analysis with modified shear strength reduction technique", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 1085-1089. Taylor & Francis.
Abstract: This paper deals with the slope stability engineering. Due to the rapid development of computing efficiency, several numerical methods are gaining increasing popularity in slope stability analysis. The most popular numerical method of slope stability estimation is shear strength reduction technique (SSR). The factor of safety (FS) for slope may be computed by reducing shear strength of soil (or rock) in stages, until the slope fails. Application of SSR for complex geology slopes is usually restricted to the weakest “link” estimation – part of slope with the lowest FS. Finite Difference Method code FLAC (FLAC, 2000) gives the opportunity to analyse several slip surfaces by using modified SSR technique (MSSR). The method is based on reducing shear properties of soils after identification of first slip surface. MSSR allows performing complete estimation of stability for any type of slope.
Calcaterra D, De Riso R and Di Martire D (2004), "Assessing shallow debris slide hazard in the Agnano Plain (Naples, Italy) using SINMAP, a physically based slope-stability model", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 177-186. Taylor & Francis.
Abstract: In the last 20 years the Agnano Plain, Naples, Italy, has been affected by several shallow landslides in its pyroclastic products. Following a geomorphologic survey, integrated by air-photo interpretation and archival research, a landslide inventory and a database were implemented, consisting of 62 mass movements, 80% of which are represented by shallow debris slides. Based on a DEM with a ground resolution of 5 m x 5 m, the SINMAP code (Pack et al. 1998) was adopted, in order to explain and eventually predict the spatial distribution of the slides. Stability Index (SI) values, calculated as a result of an infinite slope stability model, were used to classify the studied territory in six stability classes. 48 out of the 49 slides considered fell in the regions characterized by the lowest SI (lower and upper threshold slope zones, defended slope zones). Having correctly classified the shallow slides of the Agnano Plain, the SI map created with SINMAP can hence be considered as a reliable tool to mimic the landslide susceptibility of local slopes.
Calvello M, Cascini L and Sorbino G (2008), "A numerical procedure for predicting rainfall-induced movements of active landslides along pre-existing slip surfaces", International Journal For Numerical and Analytical Methods In Geomechanics., March, 2008. Vol. 32(4), pp. 327-351.
Abstract: A numerical model to predict landslide movements along pre-existing slip surfaces from rainfall data is presented. The model comprises: a transient seepage finite-element analysis to compute the variations of pore water pressures due to rainfall; a limit equilibrium stability analysis to compute the factors of safety along the slip surface associated with transient pore pressure conditions; an empirical relationship between the factor of safety and the rate of displacement of the slide along the slip surface; an optimization algorithm for the calibration of analyses and relationships based on available monitoring data. The model is validated with reference to a well-monitored active slide in central Italy, characterized by very slow movements occurring within a narrow band of weathered bedrock overlaid by a clayey silt colluvial cover. The model is conveniently divided and presented in two parts: a groundwater model and a kinematic model. In the first part, monthly recorded rainfall data are used as time-dependent flow boundary conditions of the transient seepage analysis, while piezometric levels are used to calibrate the analysis by minimizing the errors between monitoring data and computed pore pressures. In the second part, measured inclinometric movements are used to calibrate the empirical relationship between the rate of displacement along the slip surface and the factor of safety, whose variation with time is computed by a time-dependent stability analysis. Copyright (C) 2007 John Wiley & Sons, Ltd.
Caputo V, Di Maio C, Brancucci A and Vassallo R (2004), "The Spineto Landslide: pore pressure measurements and analyses", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 577-582. Taylor & Francis.
Abstract: This paper deals with a landslide in clayey soil. It reports a brief geotechnical characterization, pore pressure measurements and the results of theoretical analyses carried out in order to evaluate the influence of a drainage system on pore pressure distribution and on the slope safety factor. The analyses were carried out with both two and three-dimensional commercial finite element codes and the calculated piezometric head values were compared to the values measured before and after the construction of the drainage system. The results show that the system, due to its insufficient depth, does not influence significantly pore pressures on the shear zone.
Carbonneau PE, Lane SN and Bergeron NE (2004), "Catchment-scale mapping of surface grain size in gravel bed rivers using airborne digital imagery", Water Resources Research., July, 2004. Vol. 40(7), pp. W07202.
Abstract: This study develops and assesses two methods for estimating median surface grain sizes using digital image processing from centimeter-resolution airborne imagery. Digital images with ground resolutions of 3 cm and 10 cm were combined with field calibration measurements to establish predictive relationships for grain size as a function of both local image texture and local image semivariance. Independently acquired grain size data were then used to assess the algorithm performance. Results showed that for the 3 cm imagery both local image semivariance and texture are highly sensitive to median grain size, with semivariance being a better predictor than image texture. However, in the case of 10 cm imagery, sensitivity of image semivariance and texture to grain size was poor, and this scale of imagery was found to be unsuitable for grain size estimation. This study therefore demonstrates that local image properties in very high resolution digital imagery allow for automated grain size measurement using image processing and remote sensing methods.
Cardinali M, Reichenbach P, Guzzetti F, Ardizzone F, Antonini G, Galli M, Cacciano M, Castellani M and Salvati P (2002), "A geomorphological approach to the estimation of landslide hazards and risks in Umbria, Central Italy", Natural Hazards and Earth System Science. Vol. 2(1/2), pp. 57-72.
Abstract: We present a geomorphological method to evaluate landslide hazard and risk. The method is based on the recognition of existing and past landslides, on the scrutiny of the local geological and morphological setting, and on the study of site-specific and historical information on past landslide events. For each study area a multi-temporal landslide inventory map has been prepared through the interpretation of various sets of stereoscopic aerial photographs taken over the period 1941–1999, field mapping carried out in the years 2000 and 2001, and the critical review of site-specific investigations completed to solve local instability problems. The multi-temporal landslide map portrays the distribution of the existing and past landslides and their observed changes over a period of about 60 years. Changes in the distribution and pattern of landslides allow one to infer the possible evolution of slopes, the most probable type of failures, and their expected frequency of occurrence and intensity. This information is used to evaluate landslide hazard, and to estimate the associated risk. The methodology is not straightforward and requires experienced geomorphologists, trained in the recognition and analysis of slope processes. Levels of landslide hazard and risk are expressed using an index that conveys, in a simple and compact format, information on the landslide frequency, the landslide intensity, and the likely damage caused by the expected failure. The methodology was tested in 79 towns, villages, and individual dwellings in the Umbria Region of central Italy.
Carpentier S, Konz M, Fischer R, Anagnostopoulos G, Meusburger K and Schoeck K (2012), "Geophysical imaging of shallow subsurface topography and its implication for shallow landslide susceptibility in the Urseren Valley, Switzerland", Journal of Applied Geophysics., August, 2012. Vol. 83, pp. 46-56.
Abstract: Landslides and soil erosion are an ever present threat to water management, building construction, vegetation formation and biodiversity in the Swiss Alps. Improved understanding of the mechanics and causative factors of soil erosion is a key factor in mitigation of damage to Alpine natural resources. Recently, much progress has been achieved in the forecasting of landslides on Alpine slopes with a new generation of shallow landslide models. These models perform well in spatial predictions, but temporal control on the occurrence of shallow landslides is less successful. Realistic soil composition and geometry of interfaces are necessary input for better predictions. Geophysical methods have so far not been widely considered to obtain these parameters, in spite of their ability to cover much ground with high-resolution. In this study we successfully use such methods to derive adequate subsurface topography as input to dynamic spatially distributed hydrological and soil mechanical models. Trench, GPS, electrical resistivity tomography and ground penetrating radar data were collected, resulting in revealing images of the composition and geometry of past and future landslides. A conceptual model for the occurrence of local shallow landslides is derived, spanning from block-wise steady creep of detaching soil units to rapid sliding and downslope deposition of soil units via varying sliding planes. Significant topography was observed in the soil interfaces acting as sliding planes, leading to a more complex role of groundwater flow in the initiation of shallow landslides. Hydrogeologic models should be revised accordingly. (c) 2012 Elsevier B.V. All rights reserved.
Carrara A (1983), "Multivariate models for landslide hazard evaluation", Journal of the International Association for Mathematical Geology. Vol. 15(3), pp. 403-426. Kluwer Academic Publishers-Plenum Publishers.
Abstract: As part of a long-term project aimed at a better understanding of the geological and geomorphological factors that control slope instability phenomena in Southern Italy, multivariate models for assessing landslide incidence hazard were developed and tested in two Calabrian sample areas characterized by different geological-geomorphologieal conditions. Discriminant analysis, based on a large set of mappable geological and geomorphical variables, is able to discriminate rather successfully between stable and unstable areas or slope units. Multiple regression analysis has also proved to be a useful tool in predicting actual and potential landslide hazard. Consequently, geomathematical models may provide a feasible approach to environmental hazard assessment, particularly when applied within the framework of a wider multidisciplinary project for land evaluation and planning.
Carrara A, Cardinali M, Detti R, Guzzetti F, Pasqui V and Reichenbach P (1991), "GIS techniques and statistical models in evaluating landslide hazard", Earth Surf. Process. Landforms. Vol. 16(5), pp. 427-445. John Wiley & Sons, Ltd.
Abstract: Geographical Information Systems (GIS) and numerical cartography may greatly facilitate the development and use of statistical models for the assessment of regional landslide hazard. From a small drainage basin located in Central Italy, relevant geological and geomorphological factors were collected and processed by applying GIS technology. In particular, modules were used which both generate high-fidelity digital terrain models and automatically partition the terrain into main slope-units. The resulting information was then analysed by discriminant analysis which enabled landslide hazard and risk to be evaluated in each slope-unit. Although not lacking drawbacks, the method proved to be a feasible and cost-effective approach to landslide susceptibility assessment and mapping.
Carrara A, Cardinali M, Guzzetti F and Reichenbach P (1995), "Gis Technology in Mapping Landslide Hazard", In Geographical Information Systems in Assessing Natural Hazards. Vol. 5, pp. 135-175. Springer Netherlands.
Carrara A, Guzzetti F, Cardinali M and Reichenbach P (1999), "Use of GIS technology in the prediction and monitoring of landslide hazard", Natural Hazards., November, 1999. Vol. 20(2-3), pp. 117-135.
Abstract: Technologies such as Geographical Information Systems (GIS) have raised great expectations as potential means of coping with natural disasters, including landslides. However, several misconceptions on the potential of GIS are widespread. Prominent among these is the belief that a landslide hazard map obtained by systematic data manipulation within a GIS is assumed to be more objective than a comparable hand-made product derived from the same input data and founded on the same conceptual model. Geographical data can now be handled in a GIS environment by users who are not experts in either GIS or natural hazard process fields. The reality of the successful application of GIS within the landslide hazard domain seems to be somewhat less attractive than current optimistic expectations. In spite of recent achievements, the use of GIS in the domain of prevention and mitigation of natural catastrophes remains a pioneering activity. Diffusion of the technology is still hampered by factors such as the difficulty in acquiring appropriate raw data, the intrinsic complexity of predictive models, the lack of efficient graphical user interfaces, the high cost of digitisation, and the persistence of bottlenecks in hardware capabilities. In addition, researchers are investing more in tuning-up hazard models founded upon existing, often unreliable data than in attempting to initiate long-term projects for the acquisition of new data on the causes of catastrophic events. Governmental institutions are frequently involved in risk reduction projects whose design and implementation appear to be governed more by political issues than by technical ones. There is an unfortunate general tendency to search for data which can be collected at low cost rather than attempting to capture the information which most readily explains the causes of a disaster. If the technical, cultural, economic and political reasons for this unhealthy state cannot be adequately tackled, the International Decade for Natural Disaster Reduction will probably come to an end without achieving significant advances in the prediction and control of natural disasters.
Carsel RF and Parrish RS (1988), "Developing Joint Probability-distributions of Soil-water Retention Characteristics", Water Resources Research., May, 1988. Vol. 24(5), pp. 755-769.
Abstract: A method is presented for developing probability density functions for parameters of soil moisture relationships of capillary head [h(0)] and hydraulic conductivity [K(0)]. These soil moisture parameters are required for the assessment of water flow and solute transport in unsaturated media. The method employs a statistical multiple regression equation proposed in the literature for estimating [h(O)] or [K(O)] relationships using the soil saturated water content and the percentages of sand and clay. In the abscnce of known statistical distributions for either [h(0)] or [K(O)] relationships, the method facilitates modeling by providing variability estimates that can be used to examine the uncertainty associated with water flow or solute transport in unsaturated media.
Casadel M, Dietrich WE and Miller NL (2003), "Testing a model for predicting the timing and location of shallow landslide initiation in soil-mantled landscapes", Earth Surface Processes and Landforms., August, 2003. Vol. 28(9), pp. 925-950.
Abstract: The growing availability of digital topographic data and the increased reliability of precipitation forecasts invite modelling efforts to predict the timing and location of shallow landslides in hilly and mountainous areas in order to reduce risk to an ever-expanding human population. Here, we exploit a rare data set to develop and test such a model. In a 1.7 km(2) catchment a near-annual aerial photographic coverage records just three single storm events over a 45 year period that produced multiple landslides. Such data enable us to test model performance by running the entire rainfall time series and determine whether just those three storms are correctly detected. To do this, we link a dynamic and spatially distributed shallow subsurface runoff model (similar to TOPMODEL) to an infinite slope model to predict the spatial distribution of shallow landsliding. The spatial distribution of soil depth, a strong control on local landsliding, is predicted from a process-based model. Because of its common availability, daily rainfall data were used to drive the model. Topographic data were derived from digitized 1 : 24 000 US Geological Survey contour maps. Analysis of the landslides shows that 97 occurred in 1955, 37 in 1982 and five in 1998, although the heaviest rainfall was in 1982. Furthermore, intensity-duration analysis of available daily and hourly rainfall from the closest raingauges does not discriminate those three storms from others that did not generate failures. We explore the question of whether a mechanistic modelling approach is better able to identify landslide-producing storms. Landslide and soil production parameters were fixed from studies elsewhere. Four hydrologic parameters characterizing the saturated hydraulic conductivity of the soil and underlying bedrock and its decline with depth were first calibrated on the 1955 landslide record. Success was characterized as the most number of actual landslides predicted with the least amount of total area predicted to be unstable. Because landslide area was consistently overpredicted, a threshold catchment area of predicted slope instability was used to define whether a rainstorm was a significant landslide producer. Many combinations of the four hydrological parameters performed equally well I-or the 1955 event, but only one combination successfully identified the 1982 storm as the only landslide-producing storm during the period 1980-86. Application of this parameter combination to the entire 45 year record successfully identified the three events, but also predicted that two other landslide-producing events should have occurred. This performance is significantly better than the empirical intensity-duration threshold approach, but requires considerable calibration effort. Overprediction of instability, both for storms that produced landslides and for non-producing storms, appears to arise from at least four causes: (1) coarse rainfall data time scale and inability to document short rainfall bursts and predict pressure wave response; (2) absence of local rainfall data; (3) legacy effect of previous landslides; and (4) inaccurate topographic and soil property data. Greater resolution of spatial and rainfall data, as well as topographic data, coupled with systematic documentation of landslides to create time series to test models, should lead to significant improvements in shallow landslides forecasting. Copyright (C) 2003 John Wiley Sons, Ltd.
Cascini L, Cuomo S and Della Sala M (2011), "Spatial and temporal occurrence of rainfall-induced shallow landslides of flow type: A case of Sarno-Quindici, Italy", Geomorphology., March, 2011. Vol. 126(1-2), pp. 148-158.
Abstract: Rainfall-induced shallow landslides of flow type provide unstable masses which often travel long run-out distances with high velocities, thus posing a high societal risk when they affect large areas. Therefore, analysis of their spatial and temporal occurrence is relevant to landslide hazard assessment as the first step of the risk analysis. In order to address this issue, this paper outlines a multidisciplinary procedure that is applied to the May 1998 Sarno-Quindici landslides (southern Italy), whose spatial and temporal occurrence is not satisfactorily addressed in current literature. The spatial occurrence of the landslides is analysed using heuristic models for both the source and propagation areas. The temporal occurrence of the landslides is firstly compiled and then related to the cumulated rainfall, stratigraphy and hydraulic boundary conditions. Finally, the spatial and temporal occurrence of the main landslide triggering mechanism is modelled over the whole affected area by analysing the groundwater regime and slope stability conditions. The obtained results show that the spatial and temporal occurrence is strongly related to stratigraphy and hydraulic boundary conditions at both the slope and massif scales. They also highlight a suitable procedure for assessing the spatial and temporal occurrence of complex landslides over large areas. (C) 2010 Elsevier B.V. All rights reserved.
Cascini L, Peduto D, Pisciotta G, Arena L, Ferlisi S and Fornaro G (2013), "The combination of DInSAR and facility damage data for the updating of slow-moving landslide inventory maps at medium scale", Natural Hazards and Earth System Science. Vol. 13(6), pp. 1527-1549.
Abstract: Testing innovative procedures and techniques to update landslide inventory maps is a timely topic widely discussed in the scientific literature. In this regard remote sensing techniques – such as the Synthetic Aperture Radar Differential Interferometry (DInSAR) – can provide a valuable contribution to studies concerning slow-moving landslides in different geological contexts all over the world. In this paper, DInSAR data are firstly analysed via an innovative approach aimed at enhancing both the exploitation and the interpretation of remote sensing information; then, they are complemented with the results of an accurate analysis of survey-recorded damage to facilities due to slow-moving landslides. In particular, after being separately analysed to provide independent landslide movement indicators, the two datasets are combined in a DInSAR-Damage matrix which can be used to update the state of activity of slow-moving landslides. Moreover, together with the information provided by geomorphological maps, the two datasets are proven to be useful in detecting unmapped phenomena. The potentialities of the adopted procedure are tested in an area of southern Italy where slow-moving landslides are widespread and accurately mapped by using geomorphological criteria.
Caviezel C, Kuhn NJ and Meusburger K (2010), "Applicability of Alp Inspection Reports for the Reconstruction of Land-Use and Mass Wasting History in the Ursern Valley, Switzerland", Die Erde. Vol. 141(4), pp. 301-319.
Abstract: Changes in land use and climate can increase landscape susceptibility for mass wasting. This study illustrates a method aimed at reconstructing landscape susceptibility for mass wasting in the Ursern Valley, Switzerland, based on an analysis of alp inspection reports of the years 1950-2000. The yearly reports were written by farmers commissioned to supervise pasture use and condition on the communal land. The analysis offers the possibility to reconstruct mass wasting history, its patterns in time and space as well as its determining factors. Preliminary results show that mass wasting frequency increased since 1970 and that the recorded events are not distributed uniformly in time and space, but concentrated on geologically sensitive slopes which experienced an increase in grazing intensity.
Ceaglio E, Meusburger K, Freppaz M, Zanini E and Alewell C (2012), "Estimation of soil redistribution rates due to snow cover related processes in a mountainous area (Valle d'Aosta, NW Italy)", Hydrology and Earth System Sciences. Vol. 16(2), pp. 517-528.
Abstract: Mountain areas are widely affected by soil erosion, which is generally linked to runoff processes occurring in the growing season and snowmelt period. Also processes like snow gliding and full-depth snow avalanches may be important factors that can enhance soil erosion, however the role and importance of snow movements as agents of soil redistribution are not well understood yet. The aim of this study was to provide information on the relative importance of snow related processes in comparison to runoff processes. In the study area, which is an avalanche path characterized by intense snow movements, soil redistribution rates were quantified with two methods: (i) by field measurements of sediment yield in an avalanche deposition area during 2009 and 2010 winter seasons; (ii) by caesium-137 method, which supplies the cumulative net soil loss/gain since 1986, including all the soil erosion processes. The snow related soil accumulation estimated with data from the deposit area (27.5 Mg ha(-1) event(-1) and 161.0 Mg ha(-1) event(-1)) was not only higher than the yearly sediment amounts, reported in literature, due to runoff processes, but it was even more intense than the yearly total deposition rate assessed with Cs-137 (12.6 Mg ha(-1) yr(-1)). The snow related soil erosion rates estimated from the sediment yield at the avalanche deposit area (3.7 Mg ha(-1) and 20.8 Mg ha(-1)) were greater than the erosion rates reported in literature and related to runoff processes; they were comparable to the yearly total erosion rates assessed with the Cs-137 method (13.4 Mg ha(-1) yr(-1) and 8.8 Mg ha(-1) yr(-1)). The Cs-137 method also showed that, where the ground avalanche does not release, the erosion and deposition of soil particles from the upper part of the basin was considerable and likely related to snow gliding. Even though the comparison of both the approaches is linked to high methodological uncertainties, mainly due to the different spatial and temporal scales considered, we still can deduce, from the similarity of the erosion rates, that soil redistribution in this catchment is driven by snow movement, with a greater impact in comparison to the runoff processes occurring in the snow-free season. Nonetheless, the study highlights that soil erosion processes due to the snow movements should be considered in the assessment of soil vulnerability in mountain areas, as they significantly determine the pattern of soil redistribution.
Cerdan O, Poesen J, Govers G, Saby N, Le Bissonnais Y, Gobin A, Vacca A, Quinton J, Auerswald K, Klik A, Kwaad F and Roxo M (2006), "Soil Erosion in Europe" , pp. 501-514. Wiley.
Abstract: Water erosion is commonly divided into different subprocesses. This chapter focuses on erosion processes ranging from sheet (or intenill) erosion, which consists of the removal of a fairly uniform layer of soil by raindrop splash and sheet flow, to lill erosion, which results in the formation of numerous and randomly occurring small channels of only several centimeters depth under the action of small, intermittent water courses usually also only several centimeters deep (Glossary of Soil Science Terms, http://www.soils.org/ sssagloss). To measure the rates and extent of sheet and rill erosion, both indirect and direct methods have been used. Indirect methods generally measure soil profile truncation or sediment accumulation relative to a reference soil horizon, to an exposed or bmied reference object (exposed or buried roots, foundations, etc.), or to the loss or accumulation of tracers. These methods are more appropriate for studying historical erosion. To assess current sheet and rill erosion rates, direct methods, mainly plot or catchment monitoring and field-based measurements (e.g. mapping of erosion features) are reported. Field-based methods are most effective to answer questions such as, where does linear erosion occur and is it a problem? However, they cannot properly monitor sheet erosion and, more important for this study, their applications have been restricted to very few places in Europe. The best available data to compare soil erosion rates in Europe induced by sheet and rill processes come from plot measurements. These represent relatively well-standardized data, which can give reliable infonnation on slope sensitivity to sheet and lill erosion under a given set of conditions, and they are widespread. Based on a large dataset of soil erosion measurements under natural rainfall at the plot scale, the objectives of this study were (i) to quantify the different sheet and rill erosion rates in various agroenvironmental settings throughout western and central Europe, (ii) to identify the more at-risk situations in terms of land use or physiographic conditions and (iii) to assess overall sheet and rill erosion rates for Europe.
Ceriani M, Lauzi S and Padovan N (1992), "Rainfalls and landslides in the alpine area of Lombardia Region-Central Alps-Italy", In Proc. of the VII International Congress Interpraevent 1992, Bern. Bern Vol. 2, pp. 9-20.
Abstract: Exceptional meteorological events like those occurred during the last years on Alps pointed out the importance of rainfalls as primary cause of hydrogeological accidents. In particular during July 1987 a lot of slides occurred on wide areas, causing damages along the valley of Adda, Brembo and Oglio rivers. The aim of the present work is to propose an hydrological model and look for rainfalls thresholds triggering landslides and floods. This in order to set up an alarm system with an automatic hydro-pluviometrical network transmitting data in real time.
Cernusca A, Tappeiner U, Bahn M, Bayfield N, Chemini C, Fillat F, Graber W, Rosset M, Siegwolf R and Tenhunen J (1996), "Ecomont - Ecological effects of land use changes on European terrestrial mountain ecosystems", Pirineos. Vol. 147-148, pp. 145-172.
Abstract: As a contribution to the Terrestrial Ecosystem Research Initiative (TERI) within Framework IV of the EU, ECOMONT aims at investigating ecological effects of land-use changes in European terrestrial mountain ecosystems. ECOMONT is coordinated by Prof Cernusca (University of Innsbruck) and is carried out by eight European partner teams in the Eastern Alps, the Swiss Alps, the Spanish Pyrennees and the Scottish Highlands. ECOMONT focuses on an analysis of structures and processes in the context of land-use changes, scaling from the leaf to the landscape level. The following research topics are being investigated: Spatial distribution of vegetation and soil in the composite experimental sites; physical and chemical soil properties, SOM status and turnover; canopy structure, primary production, and litter decomposition; water relations of ecosystems and hydrology of catchment areas; microclimate and energy budget of ecosystems; gas exchange of single plants and ecosystems; gas exchange between the composite experimental sites and the atmosphere, population and plant biology of keyspecies, plant-animal interactions, potential risks through land-use changes; GIS; remote sensing - environmental mapping; modelling activities integrating from plant to ecosystem and landscape level. First results of ECOMONT show that land-use changes have strong impacts on vegetation composition, structure and processes, on soil physics and chemistry, and therefore strongly affect exchange processes with the atmosphere and biogeochemical cycles. Abandonment of traditionalagricultural practices (grazing, mowing) causes.characteristic changes of the vegetation. In most cases a successional reversion over many decades reaches its climax with the vegetation growing naturally at the sites. Sometimes, however, abandonment can also lead fo a degradation of vegetation and soil. In spite of common principles of changes of vegetation, soils and related processes with altered land-use geology, climate, exposition, slope inclination and land-use history may play an important role in determining species composition and specific patterns and processes on a community, ecosystem and landscape level in different European terrestrial mountain ecosystems.
Chacon J, Irigaray C, Fernandez T and El Hamdouni R (2006), "Engineering geology maps: landslides and geographical information systems", Bulletin of Engineering Geology and the Environment., December, 2006. Vol. 65(4), pp. 341-411.
Abstract: IAEG Commission No. 1-Engineering Geological Maps-is developing a guide to hazard maps. Scientists from 17 countries have participated. This paper is one of a series that presents the results of that work. It provides a general review of GIS landslide mapping techniques and basic concepts of landslide mapping. Three groups of maps are considered: maps of spatial incidence of landslides, maps of spatial-temporal incidence and forecasting of landslides and maps of assessment of the consequences of landslides. With the current era of powerful microcomputers and widespread use of GIS packages, large numbers of papers on the subject are becoming available, frequently founded on different basic concepts. In order to achieve a better understanding and comparison, the concepts proposed by Varnes (Landslide hazard zonation: a review of principles and practice, 1984) and Fell (Some landslide risk zoning schemes in use in Eastern Australua and their application 1992; Landslide risk assessment and acceptable risk. Can Geotech J 31:261-272, 1994) are taken as references. It is hoped this will also add to the international usefulness of these maps as tools for landslide prevention and mitigation. Six hundred and sixty one papers and books related to the topic are included in the references, many of which are reviewed in the text.
Chadwick J, Dorsch S, Glenn N, Thackray G and Shilling K (2005), "Application of multi-temporal high-resolution imagery and GPS in a study of the motion of a canyon rim landslide", Isprs Journal of Photogrammetry and Remote Sensing., June, 2005. Vol. 59(4), pp. 212-221.
Abstract: Change detection techniques using co-registered high-resolution satellite imagery and archival digital aerial photographs have been used in conjunction with GPS to constrain the magnitude and timing of previously undocumented historical motion of the Salmon Falls landslide in south-central Idaho, USA. The landslide has created natural dams of Salmon Falls Creek, resulting in the development of large lakes and a potential flooding hazard. Rapid motion (cm/year-m/year) of the relatively remote landslide was first reported in 1999, but significant horizontal motion (up to 10.8 m) is demonstrated between 1990 and 1998 by measuring changes in the locations of ground control points in a time-series of images. The total (three-dimensional) motion of the landslide prior to 2002 was calculated using the horizontal (two-dimensional) velocities obtained in the image change detection study and horizontal-to-vertical ratios of motion derived for the landslide in 2003-2004 collected from a network of autonomous GPS stations. The total historical motion that was estimated using this method averages about 12 m, which is in agreement with field observations. (c) 2005 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS). Published by Elsevier B.V. All rights reserved.
Chang F-J and Chung C-H (2012), "Estimation of riverbed grain-size distribution using image-processing techniques", Journal of Hydrology . Vol. 440–441(0), pp. 102 - 112.
Abstract: Summary Quantification of the grain size distribution of fluvial gravels remains an important and challenging issue in the study of river behavior. It is desirable for sampling techniques to achieve accurate estimation of grain size distribution, while simultaneously reducing the time spent. Recent advances in image analysis techniques have facilitated automated grain identification and measurement within digital images. In this study, an image-processing method fusing feedback pulse couple neural network and multilevel thresholding, the I-FM method, is proposed for automatic extraction of grain-size distribution based on digital photographs taken from a river-bed. A decisive image-merging algorithm is also developed for improving the quality of image segmentation in grain-size measurements. The experiments were conducted in both lab and field, and the proposed method was compared with traditional image processing methods. The proposed I-FM produces much more satisfactory results in estimating the amount of gravel and the percentiles of grain-size distribution in comparison with other image processing methods and manual sieving methods. It demonstrates the I-FM method is an efficient method for precisely measuring the grain-size distribution of river-bed material.
Chang K-T, Veldkamp A and Borga M (2011), "Preface: Modeling land dynamics in mountainous environments", Geomorphology., October, 2011. Vol. 133(3-4), pp. 117-120.
Abstract: Globally the distribution of mountains is related to those regions where tectonic plates collide or have been colliding. Many active plate margins are characterized by rapidly uplifting mountains, accompanied by large earthquakes. Some tectonically active mountain zones are also located in regions where the monsoon, tropical cyclones (typhoons), and other rain bearing weather systems regularly bring torrential rain to mountain watersheds. The combination of steep slope gradients and abundant water naturally leads to landslides and debris flows, causing casualties and heavy economic losses to the affected areas (http://www.landslidecentre.org/database.htm). Wellknown examples of these mountain zones are found in Japan, Taiwan, Philippines, Indonesia, New Zealand, and the lower slopes on the Alpine, Andean, and Himalayan mountain ranges.
Chatwin S, Howes J, Schwab JW and Swanston D (1991), "A guide for Management of Landslide-Prone Terrain in the Pacific Northwest" Province of British Columbia Ministry of Forests, Crown Pub. Inc..
Abstract: A Guide for Management of Landslide-Prone Terrain in the Pacific Northwest has been prepared for agency and industry personnel who are operating in areas with existing or potential stability problems. The document is intended for use in the coastal areas of the Pacific Northwest, even though the principles may be applicable to other locations in North America. The guide addresses four topics:
• Slope movement processes and characteristics.
• An office/field technique for recognizing landslide-prone terrain
• Measures to manage unstable terrain during forestry activities.
• Road deactivation and revegetation of unstable terrain.
The guide is designed to be carried in field staff vehicles. A "condensed" version of the book will be available in the form of field cards that can be more easily carried in field note books. They will provide some of the basic information contained in this larger document.
Che VB, Kervyn M, Suh CE, Fontijn K, Ernst GGJ, del Marmol MA, Trefois P and Jacobs P (2012), "Landslide susceptibility assessment in Limbe (SW Cameroon): A field calibrated seed cell and information value method", Catena., May, 2012. Vol. 92, pp. 83-98.
Abstract: The dissected volcanic terrains around Limbe, SW Cameroon are frequently affected by small scale but destructive landslides. In this study, a raster-based data driven method involving seed cells is used to build a landslide susceptibility model for the Limbe area. Factors considered to be potential controls of slope failure within this area include slope gradient, rock type, distance from roads, slope orientation, mean annual precipitation, soil type, land cover type, stream density and distance from stream. 63 small to very small translational and rotational landslide scars were identified through extensive field work. Landslide data is randomly divided into a training (75%) and validation set (25%) and seed cells are generated by creating 25 m buffer zones around the head scarp of each scar. The quantitative relationship between landslide seed cells and the above-mentioned factors is established by a data driven approach to obtain weighted factor classes. Summing weighted factor layers, a continuous scale of susceptibility indices is obtained and reclassified into 5 susceptibility classes. Seed cells obtained from the validation data set were used to evaluate the quality of several models involving different controlling factors. Our preferred model combines the weight of 6 factors (i.e. slope gradient, land cover, mean annual precipitation, stream density, proximity to roads and slope orientation). 78% of the validation seed cells are located within the high to very high susceptibility class, which occupy 16.9% of the study area. The obtained susceptibility map is combined with the outline of urban areas and key infrastructures to evaluate zones that are vulnerable to the impact of future slope failures. Such an approach will assist civil protection and urban planning efforts in SW Cameroon. (C) 2011 Elsevier B.V. All rights reserved.
Chemini C and Rizzoli A (2003), "Land use change and biodiversity conservation in the Alps", Ibex Journal of Mountain Studies. Vol. 7, pp. 1-7.
Abstract: Human activities are changing the Planet, inducing high rates of extinction and a worldwide depletion of biological diversity at genetic, species, and ecosystem level. Biodiversity not only has an ethical and cultural value, but also plays a role in ecosystem function and, thus, ecosystem services, which are essential to civilization, economic production, and human wellbeing. The functional role of biodiversity is still poorly known; a minimum level of biodiversity is required for sustainable preservation of ecosystem functions, and as an insurance for future environmental changes. A large part of the biodiversity of the Alps is linked to an interaction between the natural environment and traditional human practices. At present, the change in land-use, with both intensification and abandonment, and other environmental and socioeconomic processes at different scales (urbanization, tourism, pollution, global change, etc.) are important forces of environmental change. Mowing and livestock grazing are primary factors inhibiting woody plant succession in many areas of the Alps. Abandonment and fragmentation has resulted in an expansion of ecotones and edge, with increase in tick-hosts and possibly changes in host-parasite interactions resulting from species concentration. The abandonment of mountain fields and meadows with a consequent expansion of shrubs and forests has caused a decrease of several grassland species, such as rock partridge Alectoris graeca; some arthropod communities of grassland have also been affected. Many forest species should find new opportunities, but in several cases the forests have become too dense for some species, such as for capercaille Tetrao urogallus. In the low altitude belts, a high species diversity co-occurs with human disturbance. Biodiversity studies require an interdisciplinary approach by the life sciences, and an interface to socioeconomic sciences. Preservation of species and landscape diversity cannot prescind from a dialogue between different actors and interests.
Chen H, Lin G-W, Lu M-H, Shih T-Y, Horng M-J, Wu S-J and Chuang B (2011), "Effects of topography, lithology, rainfall and earthquake on landslide and sediment discharge in mountain catchments of southeastern Taiwan", Geomorphology., October, 2011. Vol. 133(3-4), pp. 132-142.
Abstract: From 1996 through 2007, several heavy typhoons and earthquakes precipitated landslide hazards in southeast Taiwan. In the present study, we analyze the impact of topography, lithology, rainfall and earthquakes on landsliding and sediment transport by quantifying the landslide ratio (ratio of landslide area to catchment area) and the sediment discharge for the Sinwulu and Luye upstream catchments of the Peinan River. The steep topography in these two catchments causes a large proportion of landslide ratios on slopes to exceeding 50 degrees, a condition which accelerates the delivery of landslide debris to the downslope channel. The landslide ratios of 0.84%-2.30% are obviously related to the rock strength and discontinuity density of the terrain, but we find the magnitude of landsliding and sediment discharge to vary with the occurrence of earthquakes. Typhoon-induced rainstorms generate the bulk of sediment discharge in the study catchments, though the landslide debris is transported by the huge amounts of runoff produced by rainstorms. A contributing factor is the recent occurrence of severe earthquakes which weakened the geomaterial, leading in turn to further increases of fluvial sediment during subsequent typhoons. Additionally, the finding that eventual reduction of unit sediment concentration after high magnitude earthquake events reveals that the downslope transport of landslide debris associated with earthquake activity and subsequent typhoon events precipitates a relatively short term, 1-3 year, increase of erosion rates in these two study areas in southeastern Taiwan. (C) 2011 Elsevier B.V. All rights reserved.
Chen L and Young MH (2007), "Green-Ampt infiltration model for sloping surfaces", Water Resources Research., July, 2007. Vol. 42(7), pp. W07420.
Abstract: [1] This work quantifies and explains the direct physical effects of slope angle on infiltration and runoff generation by extending the Green-Ampt equation onto sloping surfaces. A new extended solution using identical precipitation hydrographs was compared to the original formulation and then used to calculate the infiltration and runoff generation for different slope angles but for identical horizontal projection lengths. Homogeneous and isotropic soil is assumed, and two different boundary conditions for vertical rainfall are studied: ponded infiltration and infiltration under steady rainfall. Infiltration under unsteady rainfall was found to be similar to cases with steady rainfall. Both theoretical and numerical results show that infiltration increases with increasing slope angle. For cases with ponded infiltration the slope effect was generally not significant for mild to moderate slopes, but the slope effect became more important for low-intensity and short-duration rainfall events, especially as it delayed the time for ponding. It was also found that the cumulative vertical infiltration depth (I-hp) at ponding ( or the initial loss) increases with increasing slope angle. The model was compared to Richards' equation on horizontal and sloping surfaces and found to perform well. The model's applicability for nonuniform slopes was discussed, and it was found that the model is generally applicable for isotropic and mildly anisotropic soils except for some small-scale topographic elements. Finally, the occurrence of nonvertical rainfall could increase runoff with increasing slope angle when rainfall deflects a large angle to upslope.
Chen XL, Ran HL and Yang WT (2012), "Evaluation of factors controlling large earthquake-induced landslides by the Wenchuan earthquake", Natural Hazards and Earth System Science. Vol. 12(12), pp. 3645-3657.
Abstract: During the 12 May 2008, Wenchuan earthquake in China, more than 15 000 landslides were triggered by the earthquake. Among these landslides, there were 112 large landslides generated with a plane area greater than 50 000 m2. These large landslides were markedly distributed closely along the surface rupture zone in a narrow belt and were mainly located on the hanging wall side. More than 85% of the large landslides are presented within the range of 10 km from the rupture. Statistical analysis shows that more than 50% of large landslides occurred in the hard rock and second-hard rock, like migmatized metamorphic rock and carbonate rock, which crop out in the south part of the damaged area with higher elevation and steeper landform in comparison with the northeast part of the damaged area. All large landslides occurred in the region with seismic intensity > X except a few of landslides in the Qingchuan region with seismic intensity IX. Spatially, the large landslides can be centred into four segments, namely the Yingxiu, the Gaochuan, the Beichuan and the Qingchuan segments, from southwest to northeast along the surface rupture. This is in good accordance with coseismic displacements. With the change of fault type from reverse-dominated slip to dextral slip from southwest to northeast, the largest distance between the triggered large landslides and the rupture decreases from 15 km to 5 km. The critical acceleration ac for four typical large landslides in these four different segments were estimated by the Newmark model in this paper. Our results demonstrate that, given the same strength values and slope angles, the characteristics of slope mass are important for slope stability and deeper landslides are less stable than shallower landslides. Comprehensive analysis reveals that the large catastrophic landslides could be specifically tied to a particular geological setting where fault type and geometry change abruptly. This feature may dominate the occurrence of large landslides. The results will be useful for improving reliable assessments of earthquake-induced landslide susceptibility, especially for large landslides which may result in serious damages.
Chiang S-H and Chang K-T (2011), "The potential impact of climate change on typhoon-triggered landslides in Taiwan, 2010-2099", Geomorphology., October, 2011. Vol. 133(3-4), pp. 143-151.
Abstract: In the western North Pacific, including Taiwan, typhoons (tropical cyclones) and rainfall rates are predicted to intensify as a result of climate change. Because typhoons are the major triggers of shallow landslides in Taiwan, landslide activity is expected to increase as global warming continues. To assess the worst scenario of landslide occurrence in a mountainous watershed till the end of the century, this study developed a method to select a global climate model (GCM) from 21 available GCMs and correct its monthly precipitation data, before downscaling annual maximum (24-h) rainfall from the corrected GCM data as input to the factor-of-safety model for landslide prediction. Average annual maximum rainfall is expected to increase from 322 mm in 1960-2008 to 371 mm in 2010-2099. Average total unstable area is expected to increase from 1135 ha in 1960-2008 to 1280 ha in 2010-2099, a 12% increase. As a first attempt to assess landslide activity due to global warming, this study is useful as a reference for watershed management in Taiwan. The results must be evaluated in light of uncertainties caused by the correction and downscaling of GCM data and the input parameters to the slope stability model. (C) 2011 Elsevier B.V. All rights reserved.
Chigira M, Duan FJ, Yagi H and Furuya T (2004), "Using an airborne laser scanner for the identification of shallow landslides and susceptibility assessment in an area of ignimbrite overlain by permeable pyroclastics", Landslides., September, 2004. Vol. 1(3), pp. 203-209. Springer Heidelberg.
Abstract: An airborne laser scanner can identify shallow landslides even when they are only several meters in diameter and are hidden by vegetation, if the vegetation is coniferous or deciduous trees in a season with fewer leaves. We used an airborne laser scanner to survey an area of the 1998 Fukushima disaster, during which more than 1,000 shallow landslides occurred on slopes of vapor-phase crystallized ignimbrite overlain by permeable pyroclastics. We identified landslides that have occurred at the 1998 event and also previous landslides that were hidden by vegetation. The landslide density of slopes steeper than 20 degrees was 117 landslides/km(2) before the 1998 disaster. This event increased the density by 233 landslides/km(2) indicating that this area is highly susceptible to shallow landsliding.
Chugh AK and Stark TD (2006), "Permanent seismic deformation analysis of a landslide", Landslides., March, 2006. Vol. 3(1), pp. 2-12.
Abstract: A failed slope may not necessarily require a remedial treatment if it can be shown with confidence that the maximum movement of the slide mass will be within tolerable limits, i.e., not cause loss of life or property. A permanent displacement analysis of a landslide for static and seismic conditions is presented using a continuum mechanics approach. Computed values of displacement for static conditions compare favorably with field measurements and computed values of seismic displacements for a postulated earthquake motion appear reasonable. Also, the seismic displacements using the continuum mechanics approach compare favorably with those obtained using the Newmark sliding block procedure for assessing scismically-induced slope deformations.
Chung C-J and Fabbri A (2003), "Validation of Spatial Prediction Models for Landslide Hazard Mapping", Natural Hazards. Vol. 30(3), pp. 451-472. Kluwer Academic Publishers.
Chung C-J, Fabbri AG and Westen CJ (1995), "Multivariate Regression Analysis for Landslide Hazard Zonation", In Geographical Information Systems in Assessing Natural Hazards. Vol. 5, pp. 107-133. Springer Netherlands.
Chung CJF and Fabbri AG (1999), "Probabilistic prediction models for landslide hazard mapping", Photogrammetric Engineering and Remote Sensing., December, 1999. Vol. 65(12), pp. 1389-1399. Amer Soc Photogrammetry.
Abstract: A joint conditional probability model is proposed to represent a measure of a future landslide hazard, and five estimation procedures for the model are presented. The distribution of past landslides was divided into two groups with respect to a fixed time. A training set consisting of the earlier landslides and the geographical information system-based multi-layer spatial data in the study area was used to construct the prediction maps. The predictions were then cross-validated by comparing them with the remaining later landslides. When the database falls short of providing sufficient support for the prediction, the model allows the introduction of the expert's knowledge to modify the observed frequencies of the landslides with respect to the spatial data. The additional information should improve the prediction results. A case study from the Rio Chincina region in Colombia was used to illustrate the methodologies.
Claessens L, Heuvelink GBM, Schoorl JM and Veldkamp A (2005), "DEM resolution effects on shallow landslide hazard and soil redistribution modelling", Earth Surface Processes and Landforms., April, 2005. Vol. 30(4), pp. 461-477. John Wiley & Sons Ltd.
Abstract: In this paper we analyse the effects of digital elevation model (DEM) resolution on the results of a model that simulates spatially explicit relative shallow landslide hazard and soil redistribution patterns and quantities. We analyse distributions of slope, specific catchment area and relative hazard for shallow landsliding for four different DEM resolutions (grid sizes of 10, 25, 50 and 100 m) of a 12 km(2) study area in northern New Zealand. The effect of DEM resolution is especially pronounced for the boundary conditions determining a valid hazard calculation. For coarse resolutions, the smoothing effect results in a larger area becoming classified as unconditionally stable or unstable. We apply simple empirical soil redistribution algorithms for scenarios in which all sites with a certain landslide hazard fail and generate debris flow. The lower initial number of failing cells but also the inclusion of slope (limit) in those algorithms becomes apparent with coarser resolutions. For finer resolutions, much larger amounts of soil redistribution are found, which is attributed to the more detailed landscape representation. Looking at spatial patterns of landslide erosion and sedimentation, the size of the area affected by these processes also increases with finer resolutions. In general, landslide erosion occupies larger parts of the area than deposition, although the total amounts of soil material eroded and deposited are the same. Analysis of feedback mechanisms between soil failures over time shows that finer resolutions show higher percentages of the area with an increased or decreased landslide hazard. When the extent of sites with lower and higher hazards are compared, finer grid sizes and higher landslide hazard threshold scenarios tend to increase the total extent of areas becoming more stable relative to the less stable ones. Extreme care should be taken when quantifying landslide basin sediment yield by applying simple soil redistribution formulas to DEMs with different resolutions. Rather, quantities should be interpreted as relative amounts. For studying shallow landsliding over a longer timeframe, the 'perfect' DEM resolution may not exist, because no resolution can possibly represent the dimensions of all different slope failures scattered in space and time. We assert that the choice of DEM resolution, possibly restricted by data availability in the first place, should always be adapted to the context of a particular type of analysis. Copyright (c) 2005 John Wiley & Sons, Ltd.
Claessens L, Schoorl JM and Veldkamp A (2007), "Modelling the location of shallow landslides and their effects on landscape dynamics in large watersheds: An application for Northern New Zealand", Geomorphology., June, 2007. Vol. 87(1-2), pp. 16-27. Elsevier Science Bv.
Abstract: In this study we propose a model to assess the location of shallow landslides and their impact on landscape development within a timeframe of years to decades. Processes that need to be incorporated in the model are reviewed then followed by the proposed modelling framework. The capabilities of the model are explored through an application for a forested 17 km(2) study catchment in Northern New Zealand for which digital elevation data are available with a grid resolution of 25 x 25 m. The model predicts the spatial pattern of landslide susceptibility within the simulated catchment and subsequently applies a spatial algorithm for the redistribution of failed material by effectively changing the corresponding digital elevation data after each timestep on the basis of a scenario of triggering rainfall events, relative landslide hazard and trajectories with runout criteria for failed slope material. The resulting model will form a landslide module within the dynamic landscape evolution model LAPSUS. The model forms a spatially explicit method to address the effects of shallow landslide erosion and sedimentation because digital elevation data are adapted between timesteps and on- and off-site effects over the years can be simulated in this way. By visualization of the modelling results in a GIS environment, the shifting pattern of upslope and downslope (in) stability, triggering of new landslides and the resulting slope retreat by soil material redistribution due to former mass movements can be simulated and assessed. (C) 2006 Elsevier B.V. All rights reserved.
Clerici A, Perego S, Tellini C and Vescovi P (2010), "Landslide failure and runout susceptibility in the upper T. Ceno valley (Northern Apennines, Italy)", Natural Hazards., January, 2010. Vol. 52(1), pp. 1-29.
Abstract: The 'Conditional Analysis' multivariate statistical method was used to evaluate Landslide Susceptibility (LS) in an area of the Italian Northern Apennines. An Inventory Landslide map, containing 518 landslides, and seven landslide-related factor maps (lithology, elevation, slope angle and aspect, profile and tangential curvatures, bedding/slope relations) were processed using a shell script that automatically carries out the whole procedure producing a final map with five Failure Susceptibility (FS) classes. The procedure was applied separately to the most frequent landslide typologies, namely, rotational slides, flows, and complex landslides, and for each of the 127 different combinations of the seven factors. To define areas potentially affected by the down-slope movement of the depleted material, four runout belts with different probabilities were distinguished around the classes with highest FS. By overlaying the resulting map with the map of the elements at risk, namely, settlements, roads, and streams, the spatial risk in the area was assessed.
Clerici A, Perego S, Tellini C and Vescovi P (2006), "A GIS-based automated procedure for landslide susceptibility mapping by the Conditional Analysis method: the Baganza valley case study (Italian Northern Apennines)", Environmental Geology., August, 2006. Vol. 50(7), pp. 941-961.
Abstract: Among the many GIS based multivariate statistical methods for landslide susceptibility zonation, the so called "Conditional Analysis method" holds a special place for its conceptual simplicity. In fact, in this method landslide susceptibility is simply expressed as landslide density in correspondence with different combinations of instability-factor classes. To overcome the operational complexity connected to the long, tedious and error prone sequence of commands required by the procedure, a shell script mainly based on the GRASS GIS was created. The script, starting from a landslide inventory map and a number of factor maps, automatically carries out the whole procedure resulting in the construction of a map with five landslide susceptibility classes. A validation procedure allows to assess the reliability of the resulting model, while the simple mean deviation of the density values in the factor class combinations, helps to evaluate the goodness of landslide density distribution. The procedure was applied to a relatively small basin (167 km(2)) in the Italian Northern Apennines considering three landslide types, namely rotational slides, flows and complex landslides, for a total of 1,137 landslides, and five factors, namely lithology, slope angle and aspect, elevation and slope/bedding relations. The analysis of the resulting 31 different models obtained combining the five factors, confirms the role of lithology, slope angle and slope/bedding relations in influencing slope stability.
Cohen D, Lehmann P and Or D (2009), "Fiber bundle model for multiscale modeling of hydromechanical triggering of shallow landslides", Water Resources Research., October, 2009. Vol. 45, pp. W10436.
Abstract: Sudden and rapid mass movements associated with landslides and snow avalanches present a hazard to life and infrastructure, yet their predictions and triggering mechanisms remain poorly understood. Statistical methods and correlative studies have been used to produce landslide or avalanche susceptibility maps, often with limited physical basis. Mechanistic approaches based on factor-of-safety computation seldom represent the progressive transition from local failure events to a landslide and, in general, do not include heterogeneities associated with land cover or with subsurface material properties and hydrologic pathways. Focusing on rainfall-induced shallow landslides, we propose the use of the fiber bundle model (FBM), a generic yet powerful and adaptable model used in modeling fatigue and fracture of complex and disordered materials. The primary strength of the FBM is its ability to represent the progressive failure of cracks and shear zones and the ruptures of highly heterogeneous bonding elements that are present in soils at all scales. The model also provides a natural framework for interpretation of acoustic emission signatures from failing slopes, which may form the basis of a monitoring and warning system.
Colombo A, Lanteri L, Ramasco M and Troisi C (2005), "Systematic GIS-based landslide inventory as the first step for effective landslide-hazard management", Landslides., December, 2005. Vol. 2(4), pp. 291-301.
Abstract: The purpose of the so-called IFFI project (Inventario dei Fenomeni Franosi in Italia-Inventory of Landslides in Italy) and of many other related activities carried out by the Centro Regionale per le Ricerche Territoriali a Geologiche of ARPA Piemonte (Agenzia Regionale per la Protezione Ambientalo-Regional Agency for Environmental Protection), is to map all the existing landslides in Piemonte (including both results of monitoring data and available historical data). ARPA carried out new systematic surveys using airphoto interpretation and created a specific alphanumeric geological information systems (GIS)-based database to store and process all the collected data. In order to obtain proper landslide-hazard zoning, it is necessary to provide a landslide inventory and to define the relationship between landslides and geological setting. A landslide inventory represents a fundamental base of knowledge, is a very basic tool for land planning, and strongly helps the local authorities in their decision making.
Confortola G, Maggioni M, Freppaz M and Bocchiola D (2012), "Modelling soil removal from snow avalanches: A case study in the North-Western Italian Alps", Cold Regions Science and Technology., January, 2012. Vol. 70, pp. 43-52.
Abstract: Snow avalanches can exert considerable erosive forces on soils. If a snow avalanche flows directly over bare ground, basal shear forces may scrape away and entrain soil. Sediments mix up with the avalanche body and may be found within the run-out snow deposit. Based on a previous field campaign aiming to quantify the amount of sediments trapped within avalanche bodies for the study site of Lavancher, in the Aosta Valley, NW-Italy, we developed here a soil erosion model, which we preliminarily applied to that site. An already developed and tested 1-D avalanche dynamics model was modified to include soil erosion. Soil removal was triggered according to two different mechanisms, namely excess of shear and critical velocity. We used equations from the available literature to model the shear stress exerted by the avalanche flow upon the ground underneath. Critical threshold for soil removal of either shear or velocity were also retrieved from the available literature, possibly depending upon soil texture and geotechnical properties. The model performs well in reproducing soil removal for three wet-dense avalanches that occurred in the study site. Use of excess of shear mechanism to evaluate erosion seems more robust, as less dependent upon flow velocity, utmost uncertain. Albeit more accurately measured events of soil eroding avalanches seem necessary to test its performance, the model can be used henceforth as a basis for further refinement concerning geomorphologic contribution of avalanches. (C) 2011 Elsevier B.V. All rights reserved.
Conrad O, Krüger JP, Bock M and Gerold G (2006), "Soil Degradation Risk Assessment Integrating Terrain Analysis and Soil Spatial Prediction Methods", In Proceedings of the International Conference
Soil and Desertification – Integrated Research for the Sustainable Management of Soils in Drylands, 5-6 May 2006, Hamburg, Germany.
Abstract: Soil degradation risk assessment requires before all reliable soil information at commensurate scales, which, in many developing countries, is neither covered by coarse analogous soil maps nor by sparsely available soil profile analyses. Given the serious current degradation problems in the eastern Bolivian lowlands owing to deforestation and poor agricultural practices, we report on an attempt to assess soil erosion risks by integrating terrain analysis and soil spatial prediction methods. Based on homogenized top soil attributes from 191 profile samples, continuous soil texture layer were estimated, using DEM terrain attributes as predictor variables. Spatial prediction functions were defined by means of multiple regression analyses, which provided mapping results with satisfactory prediction accuracy, and moreover allowed a preliminary assessment of potential wind induced soil erosion risks at spatial high resolution.
Corominas J (1996), "Landslide recognition. Identification, Movement and Causes" Chichester , pp. 97-102. Wiley.
Corominas J (1996), "The angle of reach as a mobility index for small and large landslides", Canadian Geotechnical Journal., April, 1996. Vol. 33(2), pp. 260-271.
Abstract: The relations between the angle of reach (fahrboschung) and other indexes expressing the mobility of landslides and vertical drop, horizontal reach, and volume of landslide mass have been analyzed by means of simplified plots and regression equations. Results for 204 landslides of all sizes show that whatever the mechanism of motion, all kinds of landslides experience a continuous reduction of the angle of reach with volume increase. This reduction starts from the smallest sizes. Scattering in this relation is mostly due to mechanisms of motion and to both obstacles and topographic constraints on the path. This synthesis indicates that small landslides (less than 0.5 X 10(6) m(3)), in relative terms, display excesses of travel distance similar to large landslides. Since most small landslides are not expected to develop any change in the mechanism of progression while moving, the decrease in the reach angle with volume suggests that scale effects should be taken into account. The angle of reach is found to be a proper indicator of the relative mobility of landslides and is not dependent on the height of fall.
Corominas J (1996), "The angle of reach as a mobility index for small and large landslides: Reply", Canadian Geotechnical Journal., December, 1996. Vol. 33(6), pp. 1029-1031.
Corominas J and Moya J (1999), "Reconstructing recent landslide activity in relation to rainfall in the Llobregat River basin, Eastern Pyrenees, Spain", Geomorphology., October, 1999. Vol. 30(1-2), pp. 79-93.
Abstract: A chronology of recent landslides in the upper basin of the Llobregat River, Eastern Pyrenees, has been reconstructed from technical reports, field reconnaissance and dendrogeomorphological analysis. The precipitation conditions responsible for triggering and reactivating landslides have been deduced by analysis of rainfall records from two rain gauges located in the area. Two different rainfall patterns relate to landslide occurrence: (i) Without antecedent rainfall, high intensity and short duration rains trigger mostly debris flows and shallow slides developed in colluvium and weathered rocks. A rainfall threshold of around 190 mm in 24 h initiates failures whereas more than 300 mm in 24-48 h are needed to cause widespread shallow landsliding; (ii) with antecedent rain, moderate intensity precipitation of at least, 40 mm in 24 h reactivates mudslides and both rotational and translational slides affecting clayey and silty-clayey formations. In this case, several weeks and 200 mm of precipitation are needed to cause landslide reactivation. Dendrochronological analysis shows that landslide activity in the Eastern Pyrenees was relatively low between 1926 and 1959 but has since increased significantly with reactivation now occurring about every 3 years. (C) 1999 Elsevier Science B.V. All rights reserved.
Crosetto M, Gili JA, Monserrat O, Cuevas-González M, Corominas J and Serral D (2013), "Interferometric SAR monitoring of the Vallcebre landslide (Spain) using corner reflectors", Natural Hazards and Earth System Science. Vol. 13(4), pp. 923-933.
Abstract: This paper describes the deformation monitoring of the Vallcebre landslide (Eastern Pyrenees, Spain) using the Differential Interferometric Synthetic Aperture Radar (DInSAR) technique and corner reflectors (CRs). The fundamental aspects of this satellite-based deformation monitoring technique are described to provide the key elements needed to fully understand and correctly interpret its results. Several technical and logistic aspects related to the use of CRs are addressed including an analysis of the suitability of DInSAR data to monitor a specific landslide, a discussion on the choice of the type of CRs, suggestions for the installation of CRs and a description of the design of a CR network. This is followed by the description of the DInSAR data analysis procedure required to derive deformation estimates starting from the main observables of the procedure, i.e., the interferometric phases. The main observation equation is analysed, discussing the role of each phase component. A detailed discussion is devoted to the phase unwrapping problem, which has a direct impact on the deformation monitoring capability. Finally, the performance of CRs for monitoring ground displacements has been tested in the Vallcebre landslide (Eastern Pyrenees, Spain). Two different periods, which provide interesting results to monitor over time the kinematics of different parts of the considered landslide unit, are analysed and described.
Crosta G (1998), "Regionalization of rainfall thresholds: an aid to landslide hazard evaluation", Environmental Geology. Vol. 35(2-3), pp. 131-145. Springer-Verlag.
Abstract: Rainfall, soil properties, and morphology are major factors controlling shallow landsliding. A series of meteorological events that triggered soil slips in northern Italy were studied to define rainfall thresholds and to evaluate a possible regionalization. Soil properties, triggering rainfall, and local lithological and morphometrical settings of different sites were used as input to an infiltration model. The approach allows the recognition of several triggering conditions in the Piedmont, Pre-Alpine and Alpine regions. This suggests the need for different rainfall thresholds with respect to those derived with other methods. Intensity versus rainfall duration relationships become particularly important when related to soil permeability and thickness, and demonstrate the role of antecedent precipitation. Events with exceptional water discharge from obstructed road culverts reveal the role played by anthropic structures in triggering such phenomena. Different approaches to slope stability analysis are shown, taking into account bedrock lithology, topography, seepage, and local saturation conditions.
Crosta GB and Frattini P (2008), "Rainfall-induced landslides and debris flows", Hydrol. Process.. Vol. 22(4), pp. 473-477. John Wiley & Sons, Ltd..
Abstract: In this preface we introduce the special issue on rainfall-induced landslides and debris flows. The topic is of high interest for many practical and scientific reasons. In fact, rainfall is the most relevant factor for the triggering of both shallow and deep-seated landslides, and rainfall analysis is the most frequently adopted approach for forecasting the occurrence of such phenomena. The six papers of the special issue cover most of the key issues relative to rainfall-induced landslides. Starting from the analysis of these contributions, we identify and discuss, in this paper, several main topics that deserve further research in the field of rainfall-induced landslide, such as the uncertainty of the data, the quality of geotechnical analysis, the validation of the models, and the applicability of results in the framework of natural hazards. Copyright © 2007 John Wiley & Sons, Ltd.
Crosta GB and Frattini P (2003), "Distributed modelling of shallow landslides triggered by intense rainfall", Natural Hazards and Earth System Science. Vol. 3(1/2), pp. 81-93.
Abstract: Hazard assessment of shallow landslides represents an important aspect of land management in mountainous areas. Among all the methods proposed in the literature, physically based methods are the only ones that explicitly includes the dynamic factors that control landslide triggering (rainfall pattern, land-use). For this reason, they allow forecasting both the temporal and the spatial distribution of shallow landslides. Physically based methods for shallow landslides are based on the coupling of the infinite slope stability analysis with hydrological models. Three different grid-based distributed hydrological models are presented in this paper: a steady state model, a transient "piston-flow" wetting front model, and a transient diffusive model. A comparative test of these models was performed to simulate landslide occurred during a rainfall event (27–28 June 1997) that triggered hundreds of shallow landslides within Lecco province (central Southern Alps, Italy). In order to test the potential for a completely distributed model for rainfall-triggered landslides, radar detected rainfall intensity has been used. A new procedure for quantitative evaluation of distributed model performance is presented and used in this paper. The diffusive model results in the best model for the simulation of shallow landslide triggering after a rainfall event like the one that we have analysed. Finally, radar data available for the June 1997 event permitted greatly improving the simulation. In particular, radar data allowed to explain the non-uniform distribution of landslides within the study area.
Crozier MJ (2010), "Landslide geomorphology: An argument for recognition, with examples from New Zealand", Geomorphology., August, 2010. Vol. 120(1-2), pp. 3-15.
Abstract: The role and significance that have been ascribed to landsliding within geomorphology were examined with respect to some of the influential historical concepts of landform evolution. Landsliding was almost completely ignored as a geomorphic process in the earliest models of landform evolution. While there has been a growing acknowledgement of landsliding as a hillslope process capable of performing significant erosion and transportation, it has received only sparse recognition as a formative process in its own right. Notable exceptions are the rarely referenced model of relief development of Skempton,A.W., 1953. Soil mechanics in relation to geology. Proceedings of the Yorkshire Geological Society 29(3), 33-62 Pt.1 and the reply of Selby, M.J., 1974. Dominant geomorphic events in landform evolution. Bulletin International Association of Engineering Geology 9, 85-89 to the frequency-magnitude findings of Wolman, M.G., Miller, J.P., 1960. Magnitude and frequency of forces in geomorphic processes. Journal of Geology 68 (1), 54-74. Together, these two contributions provide a sound basis of geomechanical theory and ample empirical evidence to indicate that landslides have the potential to control landform evolution. It is proposed that landslide geomorphology systems exist, within which landslides dominate form and process by governing the mechanisms, rhythm, and pace of geomorphic change, in time and space. A review of New Zealand terrain suggests that these criteria are met in six distinctive landslide geomorphology systems. Each of these can be characterised not only by the landslide regime but also by the fundamental pre-conditions of tectonic setting and geology. It is argued that the existence of such systems and the complex interrelations involved require the recognition of a landslide geomorphology in its own right. (C) 2009 Elsevier B.V. All rights reserved.
Crozier MJ (2010), "Deciphering the effect of climate change on landslide activity: A review", Geomorphology., December, 2010. Vol. 124(3-4), pp. 260-267. Elsevier Science Bv.
Abstract: Increased landslide activity is commonly listed as an expected impact of human-induced climate change. This paper examines the theoretical and empirical bases for this assertion. It identifies the mechanisms by which climate can induce landsliding and examines the manner in which these mechanisms may respond to changes in a range of climatic parameters. It is argued that inherent limiting stability factors, which vary with different terrain conditions and landslide types, ultimately govern the nature of response to changing climate. Several modelling approaches are evaluated on the basis of their potential to predict landslide response to climate projections. Given reliable input data of appropriate form and resolution, the existing slope stability, hydrological, and statistical models are for the most part capable of yielding useful prognoses on occurrence, reactivation, magnitude and frequency of landsliding. While there is a strong theoretical basis for increased landslide activity as a result of predicted climate change, there remains a high level of uncertainty resulting from the margins of error inherent in scenario-driven global climate predictions, and the lack of sufficient spatial resolution of currently available downscaled projections. Examples from New Zealand are used to illustrate the extent to which changes resulting from human activity have affected slope stability. Changes resulting from human activity are seen as a factor of equal, if not greater, importance than climate change in affecting the temporal and spatial occurrence of landslides. (C) 2010 Elsevier B.V. All rights reserved.
Crozier MJ (2005), "Multiple-occurrence regional landslide events in New Zealand: Hazard management issues", Landslides., December, 2005. Vol. 2(4), pp. 247-256.
Abstract: Landsliding in New Zealand most commonly occurs in the form of multiple-occurrence landslide events, simultaneously involving thousands to ten thousands of landslides over areas extending up to 20,000 km(2). The scale of these events, together with their multiple-hazard character, provide a unique set of management issues that stretch the capabilities of available emergency management services. Several measures for characterising the magnitude and impact potential of these events are presented and compared. While the median density of landsliding is approximately 30 landslides/km(2), over 100 landslides/km(2) have been recorded in some events. Specific soil displacement volumes vary widely between events-New Zealand events yield a median value of approximately 140 m(3)/ha. Measured Ratios of runout length to scar length are commonly about 3:1. However, comparison between events is constrained by lack of standardisation in methods of measurement and recording. Agricultural production loss, damage to road and rail infrastructure and increased flooding are the main consequences of these events. Treatment options involve loss sharing, resource management legislation, and various forms of bin-engineering.
Crozier MJ (1999), "Prediction of rainfall-triggered landslides: A test of the antecedent water status model", Earth Surface Processes and Landforms. Vol. 24(9), pp. 825-833.
Cruden D (2000), "Some forms of mountain peaks in the Canadian Rockies controlled by their rock structure ", Quaternary International . Vol. 68-71(0), pp. 59-65.
Abstract: Different mountain shapes in sedimentary sequences in the Canadian Rockies were enhanced by glacial erosion and have been modified post-glacially by gravity-driven slope processes. Slope modification by both glacial erosion and post-glaciation landslides is related to slope geometry and rock structure, particularly bedding dip. Five mountain peak shapes in monoclinal sequences each fall into different ranges of bedding dips. (1) Castellate and (2) matterhorn mountains occur in sub-horizontal beds and their slopes are generally 35-65° and oblique to both bedding and joints. (3) Cuestas develop in gently to moderately dipping beds. Dip slopes and steeper, normal escarpments form their cataclinal and anaclinal sides, respectively, with the dihedral angle between them about 90°. (4) Hogbacks in moderately to steeply dipping beds have similar slope angles on both cataclinal and anaclinal slopes. Cataclinal slopes are either dip slopes or underdip slopes but anaclinal slopes are often steepened escarpments, the dihedral angle between the slopes is usually <90°. (5) Dogtooth mountains occur in steeply dipping to sub-vertical beds and the dihedral angle can be as low as 60°. Slope gradients on a sample of 34 peaks are closely related to landslides, particularly rock slides and rock topples. These landslide modes are controlled by bedding dips.
Cruden D (1991), "A simple definition of a landslide", Bulletin of the International Association of Engineering Geology - Bulletin de l'Association Internationale de Geologie de l'Ingenieur. Vol. 43(1), pp. 27-29. Springer-Verlag.
Abstract: One obstacle to a simple definition of "landslide" is the erroneous assumption that a landslide is, simply, a slide of land. A similar linguistic analysis would suggest that a cowboy is a male calf. The less formal analysis here starts with a review of the history of the term. With this background, some current definitions can be rephrased in the terminology of the Working Party on World Landslide Inventory (1990) to give the simple, easily-understood definition which forms the Summary. The definition is intended for informal, non-technical use.
Cruden DM and Varnes DJ (1996), "Landslides: investigation and mitigation" Vol. 247, pp. 36-75. National Academies Press.
Dachroth WR (2002), "Handbuch der Baugeologie und Geotechnik" Springer DE.
Dai FC and Lee CF (2003), "A spatiotemporal probabilistic modelling of storm-induced shallow landsliding using aerial photographs and logistic regression", Earth Surface Processes and Landforms., May, 2003. Vol. 28(5), pp. 527-545.
Abstract: Landslides constitute one of the major natural hazards that could cause significant losses of life and property. Mapping or delineating areas prone to landsliding is therefore essential for land-use activities and management decision making in hilly or mountainous regions. A landslide hazard map can be constructed by a qualitative combination of maps of site conditions, including geology, topography and geomorphology, by statistical methods through correlating landslide occurrence with geologic and geomorphic factors, or by using safety factors from stability analysis. A landslide hazard map should provide information on both the spatial and temporal probabilities of landsliding in a certain area. However, most previous studies have focused on susceptibility mapping, rather than on hazard mapping in a spatiotemporal context. This study aims at developing a predictive model, based on both quasi-static and dynamic variables, to determine the probability of landsliding in terms of space and time. The study area selected is about 13 km(2) in North Lantau, Hong Kong. The source areas of the landslides caused by the rainstorms of 18 July 1992 and 4-5 November 1993 were interpreted from multi-temporal aerial photographs. Landslide data, lithology, digital elevation model data, land cover, and rainfall data were digitized into a geographic information system database. A logistic regression model was developed using lithology, slope gradient, slope aspect, elevation, slope shape, land cover, and rolling 24 It rainfall as independent variables, since the dependent variable could be expressed in a dichotomous way. This model achieved an overall accuracy of 87.2%, with 89.5% of landslide grid cells correctly classified and found to be performing satisfactorily. The model was then applied to rainfalls of a variety of periods of return, to predict the probability of landsliding on natural slopes in space and time. It is observed that the modelling techniques described here are useful for predicting the spatiotemporal probability of landsliding and can be used by land-use planners to develop effective management strategies. Copyright 0 2003 John Wiley Sons, Ltd.
Dai FC, Lee CF and Ngai YY (2002), "Landslide risk assessment and management: an overview", Engineering Geology., April, 2002. Vol. 64(1), pp. PII S0013-7952(01)00093-X.
Abstract: Landslides can result in enormous casualties and huge economic losses in mountainous regions. In order to mitigate landslide hazard effectively, new methodologies are required to develop a better understanding of landslide hazard and to make rational decisions on the allocation of funds for management of landslide risk. Recent advances in risk analysis and risk assessment are beginning to provide systematic and rigorous processes to enhance slope management. In recent years, risk analysis and assessment has become an important tool in addressing uncertainty inherent in landslide hazards. This article reviews recent advances in landslide risk assessment and management, and discusses the applicability of a variety of approaches to assessing landslide risk. Firstly, a framework for landslide risk assessment and management by which landslide risk can be reduced is proposed. This is followed by a critical review of the current state of research on assessing the probability of landsliding, runout behavior, and vulnerability. Effective management strategies for reducing economic and social losses due to landslides are described. Problems in landslide risk assessment and management are also examined. (C) 2002 Elsevier Science B.V All rights reserved.
Damm B and Terhorst B (2010), "A model of slope formation related to landslide activity in the Eastern Prealps, Austria", Geomorphology., October, 2010. Vol. 122(3-4), pp. 338-350.
Abstract: The Rhenodanubian Flysch zone of the eastern Alps of Austria is considered to be susceptible to landslides. In the study area, an undulating low mountain landscape of the eastern European Prealps, the Flysch bedrock is superimposed by Quaternary periglacial cover beds and loess. Both, the petrography of the bedrock and the soil mechanical properties of Quaternary sediments control the slope dynamics. A database compiled for the study area comprises about 200 datasets on landslide and rock fall hazards. It covers a time span between 1771 and 2007 and shows clusters between 1940 and 1943, 1965 and 1966, 1979 and 1982 as well as in 2006. The study analyses slope stability in the light of slope formation phases with respect to weathering, erosion and geology. Furthermore, geomorphological and soil-geographical methods are combined with soil-mechanical calculations. The application of the concept of periglacial cover beds facilitates the distinction between Holocene and Pleistocene landforms and slide masses in the research area. As a result, the study shows that the properties of Quaternary sediments and the occurrence of the densely bedded basal cover beds are responsible for landslide susceptibility. The variable permeability in loess layers, in contrast to that in the underlying basal cover beds, consisting mainly of marls and clayey material, is one of the fundamental controlling factors of mass movements. In a temporal context it is evident that the stability of slopes in the study area is influenced by several phases of slope formation. The synopsis of field survey, morphometrical, geotechnical as well as laboratory analyses, and slope-stability calculation, gives evidence of five morphodynamic phases that partly reoccur in an alternating pattern. After having passed all phases, the stability of the slopes studied is increased, because modified soil-mechanical properties of the slide masses become important. As a consequence, the critical slope angle is raised by 3-5 degrees. (C) 2009 Elsevier B.V. All rights reserved.
Damm B and Terhorst B (2007), "Quaternary slope formation and landslide susceptibility in the Flysch Zone of the Vienna Forest (Austria)", In Proc. of the Conference 'Geomorphology for the Future'. Obergurgl, 09, 2007. , pp. 89-96.
Abstract: The Rhenodanubian Flysch of the northern Vienna Forest is composed by various layers of sandstones, marly shales, calcareous marls and clay shists, which are covered by Quaternary periglacial cover beds and loess deposits. This area at the margin of the eastern Alps represents an undulating landscape of the Austrian low mountain regions. The Vienna Forest Flysch region is considered to be susceptible to landslides. Both, petrography of the bedrock and soil mechanical properties of the Quaternary sediments control the current slope dynamics in the study area. In a temporal context it is evident that the stability of slopes exceeding 27° is controlled by a succession of several steps of slope formation. On the basis of field survey, laboratory analyses, and slope stability modelling, investigations on recent landslides give evidence of five different phases (completely developed profile - first sliding process - erosional phase - bedrock decomposition - second sliding phase). In general, after passing these phases the stability of the studied slopes is increased, due to the different soil mechanical properties of the potential sliding masses.
Debella-Gilo M and Etzelmüller B (2009), "Spatial prediction of soil classes using digital terrain analysis and multinomial logistic
regression modeling integrated in GIS: Examples from Vestfold County, Norway"
, Catena. Vol. 77, pp. 8-18.
Abstract: The main objectives of this study were to model the relationship between WRB-1998 soil groups and terrain attributes and predict the spatial distribution of the soil groups using digital terrain analysis and multinomial logistic regression integrated in GIS in the Vestfold County of south-eastern Norway. A digital elevation model of 25 meter grid resolution was used to derive fifteen terrain attributes. A digitized soil map of thirteen WRB soil groups at the scale of 1:25,000 was used to obtain the reference soil data for model building and validation. First, the relationships between the soil groups and the terrain attributes were modeled using multinomial logistic regression. Then, the probability that a given soil type is present at a given pixel was determined from the logit models in ARCGIS to continuously map each soil group's spatial distribution. Elevation, flow length, duration of daily direct solar radiation, slope, aspect and topographic wetness index were found to be the most significant terrain attributes correlating with the spatial distribution of the soil groups. The prediction showed higher mean probability values for each soil group in the areas actually covered by that soil group compared to other areas, indicating the reliability of the prediction. However, the prediction performed poorly for soil groups that are not greatly influenced by topography but by other factors such as human activities.
Dehn M, Burger G, Buma J and Gasparetto P (2000), "Impact of climate change on slope stability using expanded downscaling", Engineering Geology., February, 2000. Vol. 55(3), pp. 193-204. Elsevier Science Bv.
Abstract: Climate parameters affecting ground water and pore pressure fluctuations can, in many cases, trigger slope instability and hence landslide activity. Global warming due to the greenhouse effect and especially changes in precipitation patterns and air temperature might therefore have influences on future landslide activity. The present paper shows an assessment of climate change consequences for displacement rates of a mudslide in the Dolomites, Italy. The study is based on climate projections of a general circulation model (GCM). GCMs are able to successfully reproduce large-scale patterns of climate, while they show a poor performance on the regional scale. Therefore, GCM output is postprocessed with a statistical downscaling technique to derive local-scale climate change information from simulated atmospheric circulation patterns of the European-North Atlantic sector. The resulting precipitation and temperature series are introduced in a hydrological tank model, which calculates daily groundwater levels. Based on the groundwater data, a visco-plastic rheological model is applied to derive displacement rates of the mudslide as final output. The climate change signal is most pronounced for air temperature, while it is weaker but still significant for yearly precipitation, which is decreasing. As a consequence, yearly displacement rates show a significant reduction. The most dramatic changes, however, occur in spring with strongly lowered groundwater levels and consequently decreasing displacement rates. This is seen as an effect of reduced storage of winter precipitation as snow and hence decreasing meltwater amounts in early spring. The presented model chain with statistical downscaling, hydrological and rheological models allows the assessment of future landslide displacement affected by the greenhouse effect. The results, however, have to be taken with caution since in all parts of the model chain there are uncertainties that are difficult to address. (C) 2000 Elsevier Science B.V. All rights reserved.
Delaloye R, Lambiel C, Lugon R, Raetzo H and Strozzi T (2007), "ERS InSAR detecting slope movement in a periglacial mountain environment (Western Valais Alps, Switzerland)", Grazer Schriften der Geographie und Raumforschung. Vol. 43, pp. 113-120.
Abstract: The potential of ERS InSAR for detecting slope motion in a periglacial mountain environment has been tested in the western part of the Swiss Alps. An inventory has been built from the analysis of the InSAR data. It contains a large number of areas that can be possibly attributed to various types of mass movement (glacier, debris-covered glacier, rock glacier, landslide, sagging, gelifl uction) occurring with various rates of activity above the tree line. The applied methodology is briefly described and several typical examples of detected slope movement are illustrated.
Delaloye R, Lambiel C, Lugon R, Raetzo H and Strozzi T (2007), "Typical ERS InSAR signature of slope movements in a periglacial mountain environment (Swiss Alps)", In Proceedings ENVISAT Symposium 2007 - Montreux. Montreux , pp. 1-6.
Abstract: ERS InSAR has been used for mapping and assessing slope movements in an alpine periglacial test region. A large number of areas have thus been recognized as affected by mass wasting related to permafrost or not. Glaciers and most of the active geomorphic landforms display in fact typical ERS InSAR signals. A typology has been established. It can be seen as a useful tool to interpret ERS InSAR data in such a mountain environment.
Deploey J, Kirkby MJ and Ahnert F (1991), "Hillslope Erosion By Rainstorms - A Magnitude Frequency-analysis", Earth Surface Processes and Landforms., August, 1991. Vol. 16(5), pp. 399-409. John Wiley & Sons Ltd.
Abstract: Daily rainfall data for four stations in Europe and east Africa are used to obtain, by means of magnitude-frequency analysis, a measure of the Cumulative Erosion Potential (CEP) that takes into account rainfall characteristics, soil water storage, and granulometric properties of soils. The CEP has the advantage of being calculated from generally available published rainfall data, so that wide regional coverage is possible. Together with additional data on the surface configuration and on seasonal variations of rainfall and plant cover, the CEP can provide a basis for estimating hillslope erosion by overland flow.
Déqué M (2007), "Frequency of precipitation and temperature extremes over France in an anthropogenic scenario: Model results and statistical correction according to observed values", Global and Planetary Change. Vol. 57(1–2), pp. 16 - 26.
Abstract: Météo-France atmospheric model ARPEGE/Climate has been used to simulate present climate (1961–1990) and a possible future climate (2071–2100) through two ensembles of three 30-year numerical experiments. In the scenario experiment, the greenhouse gas and aerosol concentrations are prescribed by the so-called SRES-A2 hypotheses, whereas the sea surface temperature and sea ice extent come from an earlier ocean–atmosphere coupled simulation. The model covers the whole globe, with a variable resolution reaching 50 to 60 km over France. Model responses on daily minimum and maximum temperature and precipitation are analyzed over France. The distribution of daily values is compared with observed data from the French climatological network. The extreme cold temperatures and summer heavy precipitations are underestimated by the model. A correction technique is proposed in order to adjust the simulated values according to the observed ones. This process is applied to both reference and scenario simulation. Synthetic indices of extreme events are calculated with corrected simulations. The number of heavy rain (&gt;&#xa0;10 mm) days increases by one quarter in winter. The maximum length of summer dry episodes increases by one half in summer. The number of heat wave days is multiplied by 10. The response in precipitation is less when only the change in the mean is considered. Such a corrected simulation is useful to feed impact models which are sensitive to threshold values, but the correction does not reduce, and may enhance in some cases, the uncertainty about the climate projections. Using several models and scenarios is the appropriate technique to deal with uncertainty.
Derose RC, Trustrum NA, Thomson NA and Roberts AHC (1995), "Effect of landslide erosion on Taranaki hill pasture production and composition", New Zealand Journal of Agricultural Research., December, 1995. Vol. 38(4), pp. 457-471.
Abstract: Herbage accumulation, botanical composition, and selected soil properties were measured on hillslope pastures at three localities within eastern Taranaki hill country over 4 years, beginning in 1984. Measurement sites were either on uneroded soils representing top, middle, and bottom slope positions, or on landslide scars with ages ranging from 12 to 80 years. On uneroded sites, net annual herbage accumulation decreased with increasing slope angle from the bottom to the top of hillslopes. Net herbage accumulation was lower on landslide scars when compared with uneroded sites of similar slope. This was attributed to the presence of bare ground, lower soil water-holding capacities, and lower ryegrass content when compared with uneroded sites. Results confirmed previous findings from Wairarapa and Wairoa hill country, but showed that pasture recovery on landslide scars in Taranaki hill country was slower. Pasture recovery on landslide scars was greatest during the first 40 years after slipping, followed by a more gradual increase. Annual herbage accumulation on 12- and 40-year-old scars, was 24 and 74%, respectively, of uneroded levels. Further recovery was related to soil moisture status. On scars where soil moisture conditions did not limit pasture growth, net herbage accumulation recovered to levels of uneroded soils after, 80 years. In comparison, where soil moisture conditions limited pasture growth during late summer and autumn months, herbage accumulation was similar to 40-year-old scars. Results indicate that landslide erosion causes permanent reductions in mean herbage accumulation on hillslopes. These reductions increase from about 1 to 3% per decade with increasing slope angle from 28 to 42 degrees, mainly because of increased landslide densities. Model simulations suggest that the rate of reduction will decrease over longer periods, corresponding to fewer fresh landslides being produced on hillsides.
Descroix L and Gautier E (2002), "Water erosion in the southern French alps: climatic and human mechanisms", Catena., December, 2002. Vol. 50(1), pp. PII S0341-8162(02)00068-1.
Abstract: A large number of studies have focused on water erosion in the southern Alps because of its intensity and the high erodability affecting numerous outcrops in this region. The aim of this paper is to determine the relations between natural and human factors on the one hand, geomorphologic behaviour of hillslopes and fluvio-torrential dynamics at two time scales (geological and historical) on the other hand. This paper specially focuses on the recent weakening of torrential activity and its linkage with reforestation and rural desertion on the watersheds. Another objective is to compare these results with a rich mainly French scientific production on this theme. Experimental data on: current erosion measurements and the analysis of its processes on the one hand, and geomorphologic background of river beds and slopes, are compared and analysed using archives and the present knowledge on historical climate. It has been shown that the overexploitation of watersheds leads to an increase in soil loss, in the number and intensity of floods in alpine valleys, as well as to an enhancement of sediment transport. However, climatic changes during the Holocene and during the past millennium have resulted in changes in morphological behaviour of the hillslopes upstream and of river beds downstream. Moreover, a strong sedimentary deficit can be observed over the last three or four decades in all the Alpine massifs. The consequences of this sediment deficit are firstly an entrenchment of river beds, which threatens bridges and embankments. This recent trend is probably due to the excessive extraction of material in gravel pits and the sedimentation in the numerous dams built between 1920 and 1980 in the entire alpine range. However, the entrenchment appeared recently on non-exploited rivers; therefore, the deficit is also due to the success of the natural and artificial reforestation and torrent correction since the end of 19th century. (C) 2002 Elsevier Science B.V. All rights reserved.
Descroix L and Mathys N (2003), "Processes, spatio-temporal factors and measurements of current erosion in the French Southern Alps: A review", Earth Surface Processes and Landforms., August, 2003. Vol. 28(9), pp. 993-1011.
Abstract: Present erosion in mountainous areas of Western Europe causes land management problems, particularly for areas located downstream of erosion zones. Except for transalpine roads and ski resorts, economic activities no longer require as much space as they did in the past. Therefore, natural reforestation has provided significant protection for alpine hillslopes during the 20th century. However, extreme floods continue to cause severe damage in intra-alpine valleys, as well as in piedmont and surrounding plains, making the study of present water erosion phenomena very important. Many studies have investigated the processes and factors of water erosion on slopes at both the catchment and plot scales. They have focused on rock fragmentation and transportation in different fields, the spatial and temporal explanatory variables, the consequences downstream (flooding, sedimentation, river bed evolution) and the impact of floods. In the French Alps, present erosion has been studied in a variety of outcrops, with several recent studies conducted in fields such as marls, clayey deposits, molasses and moraines. These kinds of outcrops are found throughout the alpine massif, including an area of special interest on the great Jurassic black marl outcrop where badlands are frequently observable. Geomorphologists and hydrologists have been particularly interested in the strong erosion processes in marls, seeking to determine the main patterns and the impact of spatial and temporal factors on soil loss quantities. The main climatic factors of rock disaggregation were found to be the freeze-thaw and wet-dry cycles, which destroy rock cohesion, and the splash effect of rain. The principal site variables are vegetation cover, exposure and dip-slope angle. Erosion rates are two or three orders of magnitude higher on bare soils than on pastures; northern aspect slopes suffer two to four times as much soil loss as southern aspect slopes. Finally, the angle formed by the slope and the dip also determines different behaviours: erosion rates are higher when slope and dip are perpendicular than when they are parallel. The transportation agents are mostly debris flows and runoff caused by intense precipitation. Annual erosion depth in the marls is generally assumed to be substantial, up to 10 mm. The high value can be explained by the severity of the climatic conditions and the brittleness of the lithology, which results in numerous fractures. Copyright (C) 2003 John Wiley Sons, Ltd.
Descroix L, Viramontes D, Vauclin M, Barrios JLG and Esteves M (2001), "Influence of soil surface features and vegetation on runoff and erosion in the Western Sierra Madre (Durango, Northwest Mexico)", Catena., March, 2001. Vol. 43(2), pp. 115-135.
Abstract: In mountainous areas, runoff and soil erosion are closely linked to soil surface features, particularly stoniness. Depending on the size of rock fragments (gravel, pebbles, stones and/or blocks) and especially the way they are integrated into the soil matrix, they may facilitate or hinder infiltration and promote soil losses. The present study examines the role of different soil surface features and their influence on runoff formation and on soil erosion in an area seriously affected by overgrazing. Based on measurements made on hillslopes for 2 years at the plot scale, the results show that grass cover, pebbles and sand content increase runoff and erosion. Inversely, slope value, tree cover percentage, structural stability and organic matter content are negatively correlated with runoff and soil losses. It is shown that the correlations can be explained by the major role played by the surface features on hydrologic behaviour of the hillslopes. Two main surface features were identified and hydraulically characterised, namely: (i) crusted surfaces with embedded gravel widespread on gentle slopes which induce high runoff and erosion rates; and (ii) stony surfaces, where free pebbles and blocks protect the top soil against raindrops and overland flow kinetic energy and lead to reduce runoff and soil losses. (C) 2001 Elsevier Science B.V. All rights reserved.
De Vita P, Reichenbach P, Bathurst JC, Borga M, Crosta G, Crozier M, Glade T, Guzzetti F, Hansen A and Wasowski J (1998), "Rainfall-triggered landslides: a reference list", Environmental Geology. Vol. 35(2-3), pp. 219-233. Springer-Verlag.
Abstract: In preparing this special issue of Environmental Geology, authors and reviewers pointed out that the literature on the subject of rainfall-triggered mass movements is vast and scattered in journals, books, proceedings, internal and technical reports pertaining to the realm of different sciences: geomorphology, hydrology, hydrogeology, soil science, pedology, agronomy, and forestry among others. This limits our ability to get an overall understanding of what is known or available on the subject. We compiled a list of the available literature that rapidly grew to more than 450 entries. The list was compiled by searching through the international as well as national literature. Care was taken to include, where possible, references pertaining to the “grey” literature, such as that available from government and research institutions. These internal or technical reports, often unpublished, contain valuable information that remains largely unknown to the international scientific community. The reference list is comprehensive but by no means exhaustive. It contains references covering a variety of topics. Among the most important for the subject of this volume are: types, patterns, and causes of widespread landsliding; hydrological and hydrogeological causes of diffused landsliding; modelling slope groundwater response to rainfall; significance, role, extent, and availability of thresholds; scaling up versus scaling down; regionalization of detailed information on single slopes to large regions; usefulness of thresholds for the evaluation and mitigation of landslide hazard and risk.
Dietl W (2007), "Standörtlich angepasste Nutzung von Alpweiden", Bizauer Gespräche – Die Zukunft der Alpwirtschaft.
Dietl W (1990), "Alpweiden naturgemäß nutzen", Landfreund Nr. 11.
Dietrich WE, Reiss R, Hsu M-L and Montgomery DR (1995), "A process-based model for colluvial soil depth and shallow landsliding using digital elevation data", Hydrological Processes. Vol. 9(3-4), pp. 383-400. John Wiley & Sons, Ltd.
Abstract: A model is proposed for predicting the spatial variation in colluvial soil depth, the results of which are used in a separate model to examine the effects of root strength and vertically varying saturated conductivity on slope stability. The soil depth model solves for the mass balance between soil production from underlying bedrock and the divergence of diffusive soil transport. This model is applied using high-resolution digital elevation data of a well-studied site in northern California and the evolving soil depth is solved using a finite difference model under varying initial conditions. The field data support an exponential decline of soil production with increasing soil depth and a diffusivity of about 50 cm2/yr. The predicted pattern of thick and thin colluvium corresponds well with field observations. Soil thickness on ridges rapidly obtain an equilibrium depth, which suggests that detailed field observations relating soil depth to local topographic curvature could further test this model. Bedrock emerges where the curvature causes divergent transport to exceed the soil production rate, hence the spatial pattern of bedrock outcrops places constraints on the production law.The infinite slope stability model uses the predicted soil depth to estimate the effects of root cohesion and vertically varying saturated conductivity. Low cohesion soils overlying low conductivity bedrock are shown to be least stable. The model may be most useful in analyses of slope instability associated with vegetation changes from either land use or climate change, although practical applications may be limited by the need to assign values to several spatially varying parameters. Although both the soil depth and slope stability models offer local mechanistic predictions that can be applied to large areas, representation of the finest scale valleys in the digital terrain model significantly influences local model predictions. This argues for preserving fine-scale topographic detail and using relatively fine grid sizes even in analyses of large catchments.
Dikau R (2004), "Encyclopedia of Geomorphology" , pp. 644-652. Routledge-Taylor & Francis.
Dikau R (2006), "Oberflächenprozesse - ein altes oder ein neues Thema?", Geographica Helvetica. Vol. 3, pp. 170-180.
Abstract: Der vorliegende Aufsatz beruht auf einigen Aspekten des Vortrages «Die Formung der Erdoberfläche - geomorphologische Perspektiven», der im Rahmen des Workshops' «Erdoberflächenprozesse» gehalten wurde, der vom 25. bis 26. November 2005 in Göttingen stattgefunden hat. Die Beiträge und Diskussionen des Workshops bieten eine gute Gelegenheit, in diesem Themenheft der GEOGRAPHICA HELVETICA einige grundsätzliche Aspekte geomorphologischer Zugänge zur Erdoberfläche sowie neuere Forschungs und Methodenfeldder der Disziplin zu erörtern. Der Göttinger Workshop hatte Geowissenschaftler und Geomorphologen zusammengeführt, die diskutierten , in welchen Bereichen zukünftige gemeinsame Forschungsthemen weiterentwickelt werden können und möglicherweise programmatisch umzusetzen sind. Im Rahmen dieser Aktivitäten erscheint es angebracht, zunächst auf geomorphologische Paradigmen der «Erdoberfläche» einzugehen, da daraus Komplementaritäten zwischen den Disziplinen deutlich werden, die es mit Bedacht zu erkennen und zu würdigen gilt. Weiterhin sollen im Folgenden Aspekte der Theorie komplexer geomorphologischer Systeme angesprochen werden, um die es in der deutschsprachigen Disziplin merkwürdig still geblieben ist, um die allerdings in Nachbardisziplinen heftig gerungen wird.
Dikau R (2006), "Komplexe Systeme in der Geomorphologie", Mitteilungen der Österreichischen Geographischen Gesellschaft. Vol. 148, pp. 125-150.
Abstract: The paper presented focuses on the potential contributions of geomorphology to the understanding of complexity in social-ecologieal systems. Based on the hypothesis that social-ecologieal systems are characterised by "complex behaviour" or by an "increase of complexity" we suggest stepping up theoretical and empirical research on complex systems within the geomorphologic discipline. The author discusses categories of non-linear complexity in relation to the multi-scale charaeter of the palimpsest of landforms. These categories include: geomorphologic history, scale dependency, equilibrium, non-equilibrium, sensitivity, path dependency, chaos, self-organisation, adaptive cycle, "Panarchy" and resilience. Finally, the social-ecological concept of "Panarchy" is analysed with respect to its adaptation to the geomorphologic systems approach. We advocate discussing in greater detail the specific complexity approaches of diverse social-ecological programmes within the framework of international complexity science.
Dikau R (1988), "Entwurf einer geomorphographisch-analytischen Systematik von Reliefeinheiten", Heidelberger Geographische Bausteine. Vol. 5, pp. 1-45.
Abstract: Der vorliegende Entwurf einer Systematik geomorphographischer Objekte versteht sich als Basis für unsere Arbeiten bei der Entwicklung eines Digitalen Geomorphographischen Reliefmodells (DGRM) im DFG-Schwerpunktprogramm "Digitale Geowissenschaftliehe Kartenwerke" (vgl. VINKEN 1985). Die computer-gestützte Reliefmodellierung ist als Kern einer Digitalen Geomorphologischen Basiskarte (DGmBK) zu verstehen, deren methodischen und systematischen Aspekte bereits im Vorläuferprogramm zum jetzigen SPP diskutiert und bearbeitet wurden (BARSCH & SCHUSTER 1981, BARSCH, DIKAU & SCHUSTER 1986). Auf Grundlage des Ansatzes der Geomorphologischen Karte 1:25 000 der Bundesrepublik Deutschland (G MK 25) wurde von BARSCH & STÄBLEIN (1978) ein erster Entwurf eines geomorphologischen Symbolschlüssels vorgelegt (vgl. STÄBLEIN 1981). Seine systematischen Grundsätze sind in den vorliegenden Entwurf eingeflossen. Dem Entwurf gingen zwei unpublizierte Arbeitsberichte voraus (DIKAU 1986, DIKAU 1987), die mit Kollegen aus der Bodenkunde, Geologie, Ökologie und Geomorphologie innerhalb und außerhalb des Schwerpunktprogrammes fruchtbar diskutiert worden sind.
Dikau R, Brunsden D, Schrott L and Ibsen M (1996), "Landslide recognition. Identification, Movement and Causes" Chichester , pp. 274. Wiley.
Dikau R and Glade T (2002), "Gefahren und Risiken durch Massenbewegungen", Geographische Rundschau. Vol. 54(1), pp. 38-45.
Abstract: Massenbewegungen sind bruchlose und bruchhafte hangabwärts gerichtete Verlagerungen von Fels- und/oder Lockergesteinen unter Wirkung der Schwerkraft. Sie bilden in bestimmten Regionen der Erde eine beträchtliche Naturgefahr und können damit entscheidend zum Naturrisiko beitragen. Im Rahmen der Internationalen Dekade für die Reduzierung von Naturkatastrophen ist deutlich geworden, dass Gefahr und Risiko durch solche gravitative Massenbewegungen weltweit unterschätzt werden. Es ist deshalb geboten, diese Problematik systematisch zu untersuchen, an Fallbeispielen zu erläutern und zukünftige Perspektiven aufzuzeigen.
Dikau R and Schrott L (1999), "The temporal stability and activity of landslides in Europe with respect to climatic change (TESLEC): main objectives and results", Geomorphology., October, 1999. Vol. 30(1-2), pp. 1-12.
Abstract: The major aim of the European project "The temporal stability and activity of landslides in Europe with respect to climatic change (TESLEC)" was to investigate the interrelationship between landslides, climate and time. The research was focused on three main objectives: (I) developing criteria for the recognition of landslides, (2) reconstructing past distributions of landslide incidents and their relationship to climatic change parameters, and (3) developing a hydrological and slope stability modelling framework using different test sites. The results of the project are related to these major objectives and include: (1) a technical manual for landslide recognition, (2) records of landslide activity, and (3) an evaluation of different hydrological and slope stability models. Landslide activity since 1950 has been generally high at all test sites. In some areas, there has almost been a continuous activity observed since the beginning of the monitoring. The records before 1950 are incomplete and probably indicate a lack of data rather than a lack of landslide activity. Whether the observed active landslides are carrying a climate signal cannot be stated for all test sites with high confidence, since some relationships between climate and landslides are uncertain. Thus, for the present, the complexity of the relationships between climate and landsliding seems to make it not feasible to establish "universal laws'' all over Europe. On the other hand, it was possible to establish for some areas a cumulative rainfall-duration threshold for the reactivation of landslides. Future scenarios of regional precipitation were derived from downscaled general circulation model (GCM) experiments and used within simple slope hydrological and slope stability models. The evaluation of hydrological and slope stability models shows that physically based models are not always the best solution due to the model complexity and data requirements. For shallow landslides, more simple tank models are sometimes the better alternative. Future model development should strengthen considerations of fissure flow, sudden changes in permeability, larger landslide volumes and complex landslide topography. (C) 1999 Elsevier Science B.V. All rights reserved.
Dilo A, de By RA and Stein A (2007), "A system of types and operators for handling vague spatial objects", International Journal of Geogrpahical Information Science. Vol. 21, pp. 397-426.
Abstract: Vagueness is often present in spatial phenomena. Representing and analysing vague spatial phenomena requires vague objects and operators, whereas current GIS and spatial databases can only handle crisp objects. This paper provides mathematical definitions for vague object types and operators.

The object types that we propose are a set of simple types, a set of general types, and vague partitions. The simple types represent identifiable objects of a simple structure, i.e. not divisible into components. They are vague points, vague lines, and vague regions. The general types represent classes of simple type objects. They are vague multipoint, vague multiline, and vague multiregion. General types assure closure under set operators. Simple and general types are defined as fuzzy sets in R(2) satisfying specific properties that are expressed in terms of topological notions. These properties assure that set membership values change mostly gradually, allowing stepwise jumps. The type vague partition is a collection of vague multiregions that might intersect each other only at their transition boundaries. It allows for a soft classification of space. All types allow for both a finite and an infinite number of transition levels. They include crisp objects as special cases.

We consider a standard set of operators on crisp objects and define them for vague objects. We provide definitions for operators returning spatial types. They are regularized fuzzy set operators: union, intersection, and difference; two operators from topology: boundary and frontier; and two operators on vague partitions: overlay and fusion. Other spatial operators, topological predicates and metric operators, are introduced giving their intuition and example definitions. All these operators include crisp operators as special cases. Types and operators provided in this paper form a model for a spatial data system that can handle vague information. The paper is illustrated with an application of vague objects in coastal erosion.

Dilo A, de By RA and Stein A (2007), "Metrics for vague spatial objects based on the concept of mass", In IEEE International Conference on Fuzzy Systems. London, United Kingdom Vol. 1-4, pp. 803-808.
Abstract: Many spatial phenomena exhibit vagueness. Representation of such phenomena requires vague objects. In previous work, we provided definitions for vague objects: vague points, vague lines, and vague regions. Each of these objects is presented as a fuzzy set in IR(2) that satisfies well-defined properties. In this paper, we propose a number of geometric measures for vague objects, using the concept of mass distribution. The membership function of a vague object can be seen as a mass distribution. According to this view, a crisp object is a body with constant density, and a vague object is a body of varying density. We provide mathematical definitions for length of a vague line, area of a vague region, centroid of a vague object, as well as a measure for the vagueness of an object. The length of a vague line and the area of a vague region are indeed the mass of the vague line and of the vague region, respectively. Both metrics give an average of the values of the corresponding crisp metric on the alpha-cuts of the vague object. The centroid of a vague object is its centre of mass associated with a membership degree. The last metric functions as a measure of the degree of vagueness for a vague object.
DIN (Deutsches Institut für Normung) (2008), "DIN-Taschenbuch 113: Erkundung und Untersuchung des Baugrunds" , pp. 407-439. Beuth Verlag.
Abstract: Dieses Dokument legt Anforderungen an indirekte Bodenuntersuchungen mit Rammsondierungen im Rahmen geotechnischer Erkundung und Untersuchung nach EN 1997-1 und EN 1997-2 fest. Dieses Dokument umfasst die In-situ-Ermittlung des Widerstands von Böden und weichem Fels gegenüber der dynamischen Eindringung einer Sondenspitze. Ein Rammbär mit gegebener Masse und Fallhöhe wird verwendet, um die Sondenspitze einzurammen. Der Eindringwiderstand ist als die Schlagzahl definiert, die erforderlich ist, um die Sonde bis zu einer definierten Eindringtiefe zu rammen. Die Aufzeichnung erfolgt fortlaufend mit der Tiefe; allerdings werden keine Proben entnommen. Vier Verfahren sind hier enthalten, die einen weiten Bereich der spezifischen Arbeit je Schlag umfassen: - Leichte Rammsondierung (DPL): Versuch, der für die untere Grenze der Massenbandbreite der Rammsonden steht; - Mittlere Rammsondierung (DPM): Versuch, der für die mittlere Massenbandbreite der Rammsonden steht; - Schwere Rammsondierung (DPH): Versuch, der für die mittlere bis sehr schwere Massenbandbreite der Rammsonden steht; - Superschwere Rammsondierung (DPSH): Versuch, der für die obere Grenze der Massenbandbreite der Rammsonden steht. Die Versuchsergebnisse nach diesem Dokument sind zusammen mit direkten Untersuchungen (zum Beispiel Probenentnahme nach prEN ISO 22475-1) besonders für die qualitative Bewertung eines Bodenprofils oder für den relativen Vergleich mit anderen Versuchen, die in situ durchgeführt werden, geeignet. Sie dürfen auch zur Ermittlung von Festigkeits- und Verformungseigenschaften von Böden - hauptsächlich von nichtbindigen Böden, möglicherweise aber auch von feinkörnigen Böden - mithilfe geeigneter Beziehungen verwendet werden. Die Versuche können ebenfalls dazu benutzt werden, um die Tiefe sehr dicht gelagerter Schichten zu bestimmen, zum Beispiel für das Festlegen der Länge von Spitzendruckpfählen und sehr locker gelagerten, hohlraumreichen, ver- und aufgefüllten Baugrund zu erkennen. Für diese Norm ist das Gremium NA 005-05-09 AA "Baugrund; Feldversuche (SpA zu CEN/TC 341/WG 2, WG 3 und WG 5)" im DIN zuständig.
Dislich C and Huth A (2012), "Modelling the impact of shallow landslides on forest structure in tropical montane forests", Ecological Modelling., July, 2012. Vol. 239, pp. 40-53.
Abstract: Shallow landslides are an important type of natural ecosystem disturbance in tropical montane forests. Due to landslides, vegetation and often also the upper soil layer are removed, and space for primary succession under altered environmental conditions is created. Little is known about how these altered conditions affect important aspects of forest recovery such as the establishment of new tree biomass and species composition. To address these questions we utilize a process-based forest simulation model and develop potential forest regrowth scenarios. We investigate how changes in different trees species characteristics influence forest recovery on landslide sites. The applied regrowth scenarios are: undisturbed regrowth (all tree species characteristics remain like in the undisturbed forest), reduced tree growth (induced by nutrient limitation), reduced tree establishment (due to thicket-forming vegetation and dispersal limitation) and increased tree mortality (due to post-landslide erosion and increased susceptibility). We then apply these scenarios to an evergreen tropical montane forest in southern Ecuador where landslides constitute a major source of natural disturbance. Our most important findings are (a) On the local scale of a single landslide tree biomass recovers within the first 80 years after landslides for most scenarios, but it takes at least 200 years for the post-landslide forest to reach a structure (in terms of stem size distribution) similar to a mature forest. On this scale forest productivity is reduced for most regrowth scenarios. Changes in different tree species characteristics produce distinct spatio-temporal patterns of tree biomass distribution in the first decades of recovery within the landslide disturbed area. These patterns can potentially be used for identifying the dominant processes that drive forest recovery on landslide disturbed sites. (b) On the larger scale of the landscape overall tree biomass is reduced by 9-15% due to landslide disturbances. Overall forest productivity is only slightly reduced (<6%), but landslides increase landscape heterogeneity and produce hotspots of biomass loss and 'blind spots' of forest productivity. Thus landslides have a strong impact on the distribution of biomass in tropical montane forests. This study demonstrates that dynamic forest models are useful tools for complementing field based studies on landslides; they allow for testing alternative hypotheses on different sources of heterogeneity across spatial scales and investigating the influence of landslides on long-term forest dynamics. (c) 2012 Elsevier B.V. All rights reserved.
Domej G (2012), "Geophysical investigations on a system of active landslides in the village of Tusion (Pamir, Tajikistan)". Thesis at: University of Natural Resources and Life Sciences, Vienna.
Dommermuth C (1995), "Beschleunigte Bodenabtragungsvorgänge in der Kulturlandschaft des Nationalparks Berchtesgaden", Forstwissenschaftliches Centralblatt. Vol. 114, pp. 285-292.
Abstract: Im Laufe der letzten vier Jahrzehnte nehmen Bodenschäden durch beschleunigte Abtragungsvorgänge in der Kulturlandschaft des Nationalparks Berchtesgaden deutlich zu. Ist es der Berglandwirtschaft früher hinreichend gelungen, diese durch Rodung künstlich entstandenen Ökosysteme durch eine angepasste Nutzung zu stabilisieren und damit auch die Produktivität nachhaltig zu sichern, so wird sie heute dieser Aufgabe nicht mehr immer gerecht. Die Folgen sind erhöhte Abträge durch quasinatürtich ablaufende geomorphologische Prozesse. Am Beispiel des Jennergebietes im Nationalpark Berchtesgaden werden die Ursachen und Auswirkungen dieser nach wie vor aktuellen Entwicklung aufgezeigt.
Dommermuth C (1995), "Forschungsberichte" Vol. 32, pp. 148. Nationalpark Berchtesgaden.
Abstract: Über viele Jahrhunderte hinweg war die Bevölkerungsdichte und die Anzahl der Besucher in weiten Teilen der Alpen vergleichsweise gering. Mit der starken Zunahme des Siedlungsdrucks und des Fremdenverkehrs seit Beginn des 20. Jahrhunderts und insbesondere nach dem Zweiten Weltkrieg, hat sich diese Situation grundlegend verändert. Höhere Realeinkommen, vermehrte Freizeit, eine verbesserte Infrastruktur und hohe Mobilität führen zu einer immer intensiveren Nutzungsnahme sowohl der Tallagen als auch der höheren Regionen als Siedlungs-und Erholungsraum. Damit einher geht eine weitreichende Umgestaltung zahlreicher Landschaftsbereiche in den Alpen.
Domsch H, Ehlert D, Giebel A, Witzke K and Boess J (2006), "Evaluation of the soil penetration resistance along a transect to determine the loosening depth", Precision Agriculture., October, 2006. Vol. 7(5), pp. 309-326.
Abstract: The objective of this study was to evaluate the distribution of soil strength (measured as cone index, Cl) along a 600 m transect and to determine the soil loosening depth necessary to eliminate zones with soil strengths exceeding a threshold value down to a depth of 0.6 m. The transect was located at a site in a glacial drift area which was characterised by sandy deposits overlying boulder clay. A tractor-mounted multi-penetrometer array consisting of four hydraulically driven single vertical penetrometers was used to determine CI at 1-m sampling intervals as a measure of penetration resistance. The spatial fluctuation of the C1 readings in general and that of repeatedly averaged readings along the transect was examined. Furthermore, the relationships between the penetration resistance of several soil layers and the relationships between the C1 of single penetrometers were identified. Averaged C1 values over 5-m intervals were used to determine the depth of soil loosening required. By using various data sub-sets based on the averaged data of the four array mounted penetrometers and simulating several different sampling intervals, treatment intervals and threshold values of soil strength, a sampling interval of about 10 m proved to be sufficiently accurate to determine the loosening depth required.
Douglas GB, Trustrum NA and Brown IC (1986), "Effect of Soil Slip Erosion On Wairoa Hill Pasture Production and Composition", New Zealand Journal of Agricultural Research. Vol. 29(2), pp. 183-192.
Abstract: Dry matter production, botanical composition, soil fertility parameters, and foliar nutrient concentrations were measured on hillslope pastures in Wairoa in the North Island of New Zealand, for up to 3 years starting in 1982. Measurement sites were on 10 physiographically different landform units (pre-1942, 1942, 1970, and 1977 slip scars, 1970 and 1977 accumulation zones, footslope ridges, spurs, flats, and lower pumice ridges) representing the erosion-sedimentation continuum of the area. Average annual pasture production on pre-1942 scars was 7.5 t dry matter/ha. Similar yields were recorded from 1942 and 1970 scars, but the 1977 scars produced only 2.6 t dry matter/ha. A model derived from analysis of these results indicated that pasture recovery was exponential- recovery was most rapid in the first 10 years after slipping, and after 30 years there was no further increase in production. The proportions of the grass and clover pasture components increased and decreased, respectively, with increasing length of time since slipping. Soil pH and calcium levels generally declined with scar age and were lowest for spurs, but the reverse trend was generally true for potassium, phosphate retention, and sulphur. Moisture content and phosphate retention were higher on treads than scarps. All other landform units produced more dry matter annually than any slip scar. The results show the necessity of studying landform units separately in any research on hill country pastoral productivity, and confirm many of the findings from previous work in the Wairarapa, particularly those relating to the rate of pasture recovery.
Douglas-Mankin K, Srinivasan R and Arnold J (2010), "Soil and Water Assessment Tool (SWAT) model: Current developments and applications", Transactions of the ASABE. Vol. 53(5), pp. 1423-1431. American Society of Agricultural Engineers.
Duncan J and Wright S (1980), "The accuracy of equilibrium methods of slope stability analysis ", Engineering Geology . Vol. 16(1–2), pp. 5 - 17.
Abstract: Equilibrium methods of slope stability analysis all involve assumptions because the number of equilibrium equations available is smaller than the number of unknowns involved. Furthermore, a number of widely used methods do not satisfy all conditions of equilibrium, and thus do not employ all of the available equations of equilibrium. This paper discusses the inaccuracies which arise from these inevitable assumptions and these neglected conditions of equilibrium. Comparative analyses have shown that all of the methods which satisfy all conditions of equilibrium result in the same value of safety factor with an accuracy no worse than ± 5%, which is perfectly acceptable for practical purposes. Furthermore, within this range of accuracy, this may be considered to be the "correct" answer. Bishop's modified method, which does not satisfy all conditions of equilibrium, has been found to be as accurate as the methods which do so, and thus to be an effective and simple means of analyzing circular slip surfaces. The ordinary method of slices, which satisfies only one condition of equilibrium, gives factors of safety which may be as much as 50% smaller than the correct value for flat slopes with high pore pressures. Force equilibrium procedures with ill-chosen side force assumptions may give factors of safety which are 30% larger than the correct value for slopes in cohesive soils. The results of the study show how equilibrium methods may be selected which avoid significant errors arising from the mechanics of the analysis, and thus allow the engineer performing the analysis to devote his attention and effort to correct evaluation of shear strength.
Dunkerley D (1976), "A study of long-term slope stability in the Sydney Basin, Australia ", Engineering Geology . Vol. 10(1), pp. 1 - 12.
Abstract: A study of slope characteristics in part of the Sydney Basin indicates that landslide occurrence and long-term slope stability are both governed by the residual shear strength of the clay soils which weather from the Triassic shales of this area. Both the present distribution of landslides and the form of the slopes themselves lend support to this conclusion. It is found that on the Wianamatta shales forming the Razorback Range southwest of Sydney, landslides may only occur on slopes whose inclination exceeds 11°. The average value of Or measured in direct shear was found to be 22°. Values of Cr were found to be very small but positive.
Dunkerley DL (1982), "A Comment on "The Role of Stability Analysis In the Interpretation of the Evolution of Threshold Slopes"", Transactions of the Institute of British Geographers. Vol. 7(2), pp. 233-235.
Dymond J, Jessen M and Lovell L (1999), "Computer simulation of shallow landsliding in New Zealand hill country", International Journal of Applied Earth Observation and Geoinformation. Vol. 1(1), pp. 122-131.
Abstract: Much of the North Island hill country in New Zealand was converted from forest to pasture in the late 19th century, leaving slopes susceptible to landsliding during heavy rainstorms. Excessive soil loss has called into question the sustainability of pastoral farming, and increased sedimentation has caused problems downstream, such as increased flood risk and degraded fish habitats. A catchment- wide model of landslide erosion and sediment delivery to streams is required to help plan soil conservation and mitigate offsite effects. We describe a computer simulation model of shallow landslides and associated sediment delivery to streams, based on a high-resolution digital terrain model (DTM). The probability of landsliding during a storm is determined for each DTM pixel from GIS (geographic information system) layers of land systems, rainfall, vegetation/land cover, and slope. Where landslides occur, they are routed down the hillside, leaving a trail of sediment about 20 cm thick, on average, until they either reach a stream or become exhausted. Sediment delivery ratios can be calculated for any area. We demonstrate the model by assessing the effects of two afforestation scenarios on soil loss and sediment delivery for a simulated heavy storm in the Waipaoa catchment (220 x IO3 ha), using a DTM of 3200 x 3600 25m pixels.
Eagleston H and Rubin C (2013), "Non-motorized Winter Recreation Impacts to Snowmelt Erosion, Tronsen Basin, Eastern Cascades, Washington", Environmental Management., January, 2013. Vol. 51(1), pp. 167-181.
Abstract: Many recreation impact studies have focused on summer activities, but the environmental impact of winter recreation is poorly characterized. This study characterizes the impact of snowshoe/cross-country ski compaction and snowmelt erosion on trails. Trail cross-sectional profiles were measured before and after the winter season to map changes in erosion due to winter recreation. Compacted snow on the trail was 30 % more dense than snowpack off the trail before spring melt out. Snow stayed on the trail 7 days longer. Soil and organic material was transported after spring snowmelt with -9.5 +/- 2.4 cm(2) total erosion occurring on the trail transects and -3.8 +/- 2.4 cm(2) total erosion occurring on the control transect (P = 0.046). More material was transported on the trail than on the control, 12.9 +/- 2.4 versus 6.0 +/- 2.4 cm(2) (P = 0.055), however, deposition levels remained similar on the trail and on the control. Snow compaction from snowshoers and crosscountry skiers intensified erosion. Trail gradient was found to be significantly correlated to net changes in material on the trail (R-2 = 0.89, q = -0.98, P = 0.005). This study provides a baseline, showing that non-motorized winter recreation does impact soil erosion rates but more studies are needed. Trail managers should consider mitigation such as water bars, culverts and avoiding building trails with steep gradients, in order to reduce loss of soils on trails and subsequent sedimentation of streams.
Easterling DR, Evans JL, Groisman PY, Karl TR, Kunkel KE and Ambenje P (2000), "Observed variability and trends in extreme climate events: A brief review", Bulletin of the American Meteorological Society., March, 2000. Vol. 81(3), pp. 417-425.
Abstract: Variations and trends in extreme climate events have only recently received much attention. Exponentially increasing economic losses, coupled with an increase in deaths due to these events, have focused attention on the possibility that these events are increasing in frequency. One of the major problems in examining the climate record for changes in extremes is a lack of high-quality, long-term data. In some areas of the world increases in extreme events are apparent, while in others there appears to be a decline. Based on this information increased ability to monitor and detect multidecadal variations and trends is critical to begin to detect any observed changes and understand their origins.
Edgers L and Nadim F (2004), "Rainfall-induced slides of unsaturated slopes", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 2, pp. 1091-1096. Taylor & Francis.
Abstract: The mechanics of rainfall induced landslides involve the interaction of a number of complex hydrologic and geotechnical factors. The development of positive pore pressures and in some cases the reduction in soil negative pore water pressures (suctions) may be sufficient to cause a landslide. This paper describes the results of numerical studies on the effects of hydrologic and geotechnical factors on the pore pressures caused by rainfall infiltration. These studies included the effects of:
• Rainfall intensity.
• Initial groundwater level and soil suctions.
• Soil moisture characteristic and hydraulic conductivity functions.
• Nonhomogeneous soil layers.
The numerical studies include a Norwegian debris flow for which detailed hydrologic records are available.
Egner H (2006), "Autopoiesis, Form, und Beobachtung – Moderne Systemtheorie und ihr möglicher Beitrag für eine Integration von Human- und Physiogeographie.", Mitteilungen der Österreichischen Geographischen Gesellschaft. Vol. 148, pp. 92-108.
Abstract: Autopoiesis, form and observation – modern systems theory and its potential contribution to the integration of human and physical geography As it seems, geographers have based their concept and understanding of the world on the assumption that it consists of diverse systems — this is revealed by the way they refer to the earth system, ecosystems, economic systems, social systems etc. as a matter of course. In consequence, modern systems theory might serve as a kind of background theory for an integrating approach of both geographies. By focusing on three basic aspects of Niklas LUHMANN’s theory – autopoiesis, form and observation –, it becomes evident that his social systems theory conforms to the systems theories employed by diverse natural sciences. The author briefly reflects on the consequences geography – as a science – must anticipate when adopting a systems theoretical perspective. Finally, some consideration is given to the strategies to be pursued by the geographies to enhance the success of integrative projects based on systems theories.
Eidt M and Löhmannsröben R (1996), "Zusammenhänge zwischen bodenkundlichen Standortfaktoren und verschiedenen Abtragsformen", In Proc. of the VIII International Congress Interpraevent 1996, Garmisch-Partenkirchen. Garmisch-Partenkirchen Vol. 1, pp. 247-261.
Abstract: In diesem Beitrag werden Methodik und Ergebnisse zu Untersuchungen über den Einfluß des Bodens bei Abtragsprozessen in Wildbacheinzugsgebieten vorgestellt. Die Methodik besteht aus der Auswertung von Daten, die aus Verschneidung von detaillierten, großflächigen bodenkundlichen und geomorphologischen Kartierungen mit Hilfe eines Geographischen Informationsystems gewonnen werden. Die Auswertung dieser Verschneidungsdaten macht deutlich, daß sich durch eine standörtliche Betrachtung des Bodens verschiedene Abtragsprozesse zwar nicht ganzheitlich erklären lassen, daß die Kenntnis der bodenkundlichen Eigenschaften jedoch wesentlich zur Klärung der Phänomene beitragen kann. So werden Zusammenhänge deutlich zwischen verschiedenen flach- und mittelgründigen Abtragsfonmen im Lockergestein und Schluff- und Tongehalten des Bodens, seiner Wasserdurchlässigkeit, Speicherfähigkeit und Hydromorphie, nutzungsbedingten Bodenveränderungen und Kombinationen aus diesen Eigenschaften. Abschließend wird ein Versuch vorgestellt, die erzielten Ergebnisse in eine "Karte der Bereitschaft zur Entstehung von Massenbewegungen" umzusetzen.
Ellenberg H (1996), "Vegetation Mitteleuropas mit den Alpen in ökologischer, dynamischer und historischer Sicht" Stuttgart Vol. 5, pp. 561-648. Ulmer.
Ellenberg H (1996), "Vegetation Mitteleuropas mit den Alpen in ökologischer, dynamischer und historischer Sicht" Stuttgart Vol. 5, pp. 1095. Ulmer.
von Elversfeldt K (2010), "Systemtheorie in der Geomorphologie - Problemfelder, erkenntnistheoretische Konsequenzen und praktische Implikationen". Thesis at: University of Vienna, Institute for Geography.
Erener A and Duzgun HSB (2010), "Improvement of statistical landslide susceptibility mapping by using spatial and global regression methods in the case of More and Romsdal (Norway)", Landslides., March, 2010. Vol. 7(1), pp. 55-68.
Abstract: Statistical models are one of the most preferred methods among many landslide susceptibility assessment methods. As landslide occurrences and influencing factors have spatial variations, global models like neural network or logistic regression (LR) ignore spatial dependence or autocorrelation characteristics of data between the observations in susceptibility assessment. However, to assess the probability of landslide within a specified period of time and within a given area, it is important to understand the spatial correlation between landslide occurrences and influencing factors. By including these relations, the predictive ability of the developed model increases. In this respect, spatial regression (SR) and geographically weighted regression (GWR) techniques, which consider spatial variability in the parameters, are proposed in this study for landslide hazard assessment to provide better realistic representations of landslide susceptibility. The proposed model was implemented to a case study area from More and Romsdal region of Norway. Topographic (morphometric) parameters (slope angle, slope aspect, curvature, plan, and profile curvatures), geological parameters (geological formations, tectonic uplift, and lineaments), land cover parameter (vegetation coverage), and triggering factor (precipitation) were considered as landslide influencing factors. These influencing factors together with past rock avalanche inventory in the study region were considered to obtain landslide susceptibility maps by using SR and LR models. The comparisons of susceptibility maps obtained from SR and LR show that SR models have higher predictive performance. In addition, the performances of SR and LR models at the local scale were investigated by finding the differences between GWR and SR and GWR and LR maps. These maps which can be named as comparison maps help to understand how the models estimate the coefficients at local scale. In this way, the regions where SR and LR models over or under estimate the landslide hazard potential were identified.
Eriksson CP and Holmgren P (1996), "Estimating stone and boulder content in forest soils - Evaluating the potential of surface penetration methods", Catena., December, 1996. Vol. 28(1-2), pp. 121-134.
Abstract: Given the amount and variation of stones and boulders in forest soils, it is remarkable that little attention has been paid to this property in the analysis and modelling of soil processes. This study aims (a) to investigate the stoniness (relative volume of stones and boulders) of representative forest soils in central Sweden, (b) to evaluate the possibilities to predict soil stoniness with non-destructive surface penetration methods, particularly the rod penetration method suggested by Viro in 1952. The content of stones and boulders down to 0.4 m depth in forest till were quantified in 200 systematically distributed pits. The mean content of stones and boulders was 0.50 with a range of 0.14-0.78. Penetration depths were useful as predictors only for cases of stoniness below 0.50 where 75% of the Variation could be explained. The general evaluation of surface penetration methods revealed that large errors in very stony soils cannot be avoided. The major source of error is inherent in the method and not caused by sampling. This conclusion may lower expectations that ground-penetrating radar systems will become useful for predicting stoniness.
Ermini L, Catani F and Casagli N (2005), "Artificial Neural Networks applied to landslide susceptibility assessment", Geomorphology., March, 2005. Vol. 66(1-4), pp. Int Assoc Geomophologists.
Abstract: Landslide hazard mapping is often performed through the identification and analysis of hillslope instability factors, usually managed as thematic data within geographic information systems (GIS). In heuristic approaches, these factors are rated by the attribution of scores based on the assumed role played by each of them in controlling the development of a sliding process. Other more refined methods, based on the principle that the present and the past are keys to the future, have also been developed, thus allowing less subjective analyses in which landslide susceptibility is assessed by statistical relationships between past landslide events and hillslope instability factors. The objective of this research is to define a method with the ability to forecast landslide susceptibility through the application of Artificial Neural Networks (ANNs). The Riomaggiore catchment, a subwatershed of the Reno River basin located in the Northern Apennines (Italy), was chosen as an ideal test site, as it is representative of many of the geomorphological settings within this region. In the present application, two different ANNs, used in classification problems, were set up and applied: one belonging to the category of Multi-Layered Perceptron (MLP) and the other to the Probabilistic Neural Network (PNN) family. The hillslope factors that have been taken into account in the analysis were the following: (a) lithology, (b) slope angle, (c), profile curvature, (d) land cover and (e) upslope contributing area. These factors have been classified on nominal scales, and their intersection allowed 3342 homogeneous domains (Unique Condition Unit, UCU) to be singled out, which correspond to the terrain units utilized in this analysis. The model vector used to train the ANNs is a subset of that derived from the production of Unique Condition Units and consists of 3342 records organized in input and output variable vectors. In particular, the hillslope factors, once classified on nominal scales as binary numbers, represent the 19 input variables, while the presence/absence of a landslide in a given terrain unit is assumed to be the output variable. The comparison between the most up-to-date landslide inventory of the Riomaggiore catchment and the hazardous areas, as predicted by the ANNs, showed satisfactory results (with a slight preference for the MLP). For this reason, this is an encouraging preliminary approach towards a systematic introduction of ANN-based statistical methods in landslide hazard assessment and mapping. (c) 2004 Elsevier B.V. All rights reserved.
Fachleute Naturgefahren Schweiz FAN (2008), "Agenda FAN".
Farahmand A and AghaKouchak A (2013), "A satellite-based global landslide model", Natural Hazards and Earth System Science. Vol. 13(5), pp. 1259-1267.
Abstract: Landslides are devastating phenomena that cause huge damage around the world. This paper presents a quasi-global landslide model derived using satellite precipitation data, land-use land cover maps, and 250 m topography information. This suggested landslide model is based on the Support Vector Machines (SVM), a machine learning algorithm. The National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) landslide inventory data is used as observations and reference data. In all, 70% of the data are used for model development and training, whereas 30% are used for validation and verification. The results of 100 random subsamples of available landslide observations revealed that the suggested landslide model can predict historical landslides reliably. The average error of 100 iterations of landslide prediction is estimated to be approximately 7%, while approximately 2% false landslide events are observed.
Fazarinc R and Mikos M (1992), "Feststoffmobilisierung als Folge der extremen Niederschläge in Slowenien", In Proc. of the VII International Congress Interpraevent 1992, Bern. Bern Vol. 1, pp. 377-388.
Abstract: In August 1989 a catastrophic rainfall caused considerable damage along the Lahomnica and Kozarica rivers in Slovenia. The consequences were very severe. The agricultural areas, river banks and many utility components were destroyed, moreover urban areas that are situated along the river banks were flooded. All this happened because of two effects. There were enormous quantities of surface water that simply could not run just in channels and there were also catastrophic erosion processes on river banks as well. The causes and all effects of the event were analyzed and the technical report was issued. Because of the catastrophic consequences of the rainfall some of the basic concepts in water design were changed. The most important effects is that our attitude toward the water and living space has changed considerably. Water is getting the primary role in all environmentally oriented plans, that was not the case before.
Federico A, Popescu M, Fidelibus C and Interno G (2004), "On the prediction of the time of occurrence of a slope failure: a review", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 2, pp. 979-983. Taylor & Francis.
Fell R, Corominas J, Bonnard C, Cascini L, Leroi E and Savage W (2008), "Guidelines for landslide susceptibility, hazard and risk zoning for land use planning Preface", Engineering Geology., December, 2008. Vol. 102(3-4), pp. 83-84.
Abstract: The Commentary has been prepared to:
• Provide background notes to explain the reasons for adopting the provisions of the guideline.
• Elaborate on some parts of the guideline
• Provide references for additional reading.
The commentary is not meant to be a textbook on Landslide Susceptibility, Hazard and Risk Zoning.
Ferretti A, Prati C and Rocca F (2001), "Permanent scatterers in SAR interferometry", Geoscience and Remote Sensing, IEEE Transactions on. Vol. 39(1), pp. 8-20.
Abstract: Temporal and geometrical decorrelation often prevents SAR interferometry from being an operational tool for surface deformation monitoring and topographic profile reconstruction. Moreover, atmospheric disturbances can strongly compromise the accuracy of the results. The authors present a complete procedure for the identification and exploitation of stable natural reflectors or permanent scatterers (PSs) starting from long temporal series of interferometric SAR images. When, as it often happens, the dimension of the PS is smaller than the resolution cell, the coherence is good even for interferograms with baselines larger than the decorrelation one, and all the available images of the ESA ERS data set can be successfully exploited. On these pixels, submeter DEM accuracy and millimetric terrain motion detection can be achieved, since atmospheric phase screen (APS) contributions can be estimated and removed. Examples are then shown of small motion measurements, DEM refinement, and APS estimation and removal in the case of a sliding area in Ancona, Italy. ERS data have been used
Fiorucci F, Cardinali M, Carla R, Rossi M, Mondini AC, Santurri L, Ardizzone F and Guzzetti F (2011), "Seasonal landslide mapping and estimation of landslide mobilization rates using aerial and satellite images", Geomorphology., June, 2011. Vol. 129(1-2), pp. 59-70.
Abstract: We tested the possibility of using digital, color aerial ortho-photographs and monoscopic, panchromatic satellite images of comparable spatial and radiometric resolution, to map recent landslides in Italy and to update existing measures of landslide mobilization. In a 90-km(2) area in Umbria, central Apennines, rainfall resulted in abundant landslides in the period from September 2004 to June 2005. Analysis of the rainfall record determined the approximate dates of landslide occurrence and revealed that the slope failures occurred in response to moderately wet rainfall periods. The slope failures occurred primarily in cultivated terrain and left subtle morphological and land cover signatures, making the recognition and mapping of the individual landslides problematic. Despite the difficulty with the identification of the landslides without the use of stereoscopic visualization, visual analysis of the aerial and satellite images allowed mapping 457 new landslides, ranging in area 3.0 x 10(1) < A(L) < 2.5 x 10(4) m(2), for a total landslide area A(LT) = 6.92 x 10(5) m(2). To identify the landslides, the investigators adopted the interpretation criteria commonly used to identify and map landslides on aerial photography. The result confirms that monoscopic, very high resolution images taken by airborne and satellite sensors can be used to prepare landslide maps even where slope failures are difficult to detect, provided the imagery has sufficient geometric and radiometric resolutions. The different dates of the aerial (March 2005) and the satellite (June-July 2005) images allowed the temporal segmentation of the landslide information, and studying the statistics of landslide area and volume for different periods. Compared to pre-existing information on the abundance and size of the landslides in the area, the inventory obtained by studying the aerial and satellite images proved more complete. The new mapping showed 145% more landslides and 85% more landslide area than a pre-existing reconnaissance inventory. As a result of the improved mapping, the rate of landslide mobilization for the 2004-2005 landslide season was determined to be phi(L) = 27.1 mm year(-1), 30% higher than a previous estimate for the same period. This seasonal rate of landslide mobilization is significantly larger than the long-term regional erosion rate in the central Apennines. The accelerated rate is attributed to agricultural practices that favor slope instability. (C) 2011 Elsevier B.V. All rights reserved.
Florineth F (1993), "Begrünung von Erosionszonen über der Waldgrenze in Südtirol", Wildbach- und Lawinenverbau. Vol. 57(123), pp. 129-144.
Abstract: Begrünungen von Erosionsflächen über der Waldgrenze gestalten sich deshalb so schwierig, weil einmal nur eine kleine Auswahl von Handelssorten für Hochlagen geeignet ist und standortgerechtes Saatgut kaum zur Verfügung steht. Zudem reifen nur bei wenigen autochthonen Arten die Samen aus, von denen nicht alle für eine größere Saatgutproduktion geeignet sind. Auch die Einwanderung einheimischer Pflanzen in die begrünten Flächen geht auf Grund der erwähnten schlechten Keimfähigkeit der Samen und des geringen Ausdehnungswachstums alpiner Arten sehr langsam vor sich. Für eine dauerhafte Begrünung braucht es jedoch eine möglichst standortgerechte Vegetation, die wir auf vier Wegen zu erreichen versuchen.
1. Verwendung von geprüftem, höhenresistentem Handelssaatgut als pionierpflanzen, die mindestens 10 Jahre halten sollen.
2. Sammeln und Vermehren von standorteigenem Saatgut (Samen alpiner Gräser und Kräuter) für die Aussaat.
3. Sammeln von standorteigenem Saatgut für das Heranziehen von Jungpflanzen, die dann in die Lücken der begrünten Flächen eingesetzt werden.
• Vegetative Vermehrung alpiner Arten, welche ebenfalls in die begrünten Flächen verpflanzt werden.
Florineth F, Stern R and Mittendrein B (2004), "Untersuchung und Früherkennung der Erosionsanfälligkeit von alpinen Rasenbeständen", In Proc. of the X International Congress Interpraevent 2004, Riva del Garda. Riva del Garda Vol. 3, pp. 111-122.
Abstract: Der vorliegende Bericht befasst sich mit der Untersuchung von Erosion im Gebirge. Dazu wurden 1999 bis 2002 sechs Flächen zwischen 1400 und 2300 m üNN, alle in den Ostalpen gelegen, ausgewählt. Drei dieser Flächen sind aktuell von Erosion betroffen, drei weitere Flächen waren im Laufe der letzten Jahrzehnte mit Hilfe von ingenieurbiologischen Maßnahmen behandelt worden. Ziel der Untersuchungen war erstens die Evaluierung der angewendeten Methoden und zweitens die Erstellung eines Entscheidungsbehelfes, der es erlauben soll, das Erosionspotenzial eines Berghanges mit möglichst einfachen Mitteln zu eruieren. Dazu wurden umfangreiche Erhebungen der vegetations- und bodenkundlichen Gegebenheiten durchgeführt. Es zeigte sich, dass auch sehr alte ingenieurbiologische Verbauungen eine stabile und naturnahe Abdeckung der erodierten Flächen bewirkten. Allerdings waren einige der angewandten Methoden nach dem heutigen Stand des Wissens nicht optimal, was sich in einigen kleineren Problemen ausdrückte. Die Untersuchungen zur Früherkennung von Erosion zeigten, dass die alleinige Betrachtung der Vegetationsverhältnisse i.d.R. nicht ausreicht, um das Erosionspotenzial ausreichend zu bewerten. Aber schon sehr einfache Bodenuntersuchungen vor Ort liefern hier sehr gute Ergebnisse.
Florinsky I, Eilers R, Manning G and Fuller L (2002), "Prediction of soil properties by digital terrain modelling", Environmental Modelling & Software. Vol. 17, pp. 295-311.
Abstract: We investigated two approaches for large-scale analysis and prediction of the spatial distribution of soil properties in an agricultural landscape in the Canadian prairies. The first approach was based on the implementation of nine types of digital terrain models (DTMs) and regression analysis of soil and topographic data. The second approach used a concept of accumulation, transit, and dissipation zones of the landsurface. Soil properties were soil moisture, residual phosphorus, solum thickness, depth to calcium carbonate, and organic carbon content. The dependence of soil properties on topography was supported by correlations for the upper soil layer. However, topographic control of soil moisture and residual phosphorus decreased with depth. Also, correlation coefficients and regression equations describing topographic control of soil moisture and residual phosphorus differed among seasons. This imposes limitations on regression-based predictions of the spatial distribution of soil properties. The prediction of soil property distribution with the concept of accumulation, transit and dissipation zones can be more successful and appropriate than the prediction based on linear regression. The variability in relationships between soil and topographic characteristics with depth may stem from spatial variability in the rate of decline of hydraulic conductivity with depth. Temporal variability in soil–topography relationships occurs because soil properties result from interactions of a variety of pedogenetic factors and processes marked by different temporal variability. In soil studies with digital terrain modelling, there is a need to take into account four types of variability in relations between soil and relief: regional, temporal, depth, and scale.
Florinsky IV (2012), "Digital terrain analysis in soil science and geology"
Franciss F (2004), "Landslide hazard assessment on hilly terrain", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 143-150. Taylor & Francis.
Abstract: This article summarizes the author's previous and present experiences on applied morphometric analyses. It introduces the reader to a fast methodology to find quasi-unstable untouched slopes on hilly terrains. The novelty is the evaluation of 3D safety factors from digital elevation models using appropriate program codes. In a very short time, it is possible to sort all potential unstable slopes over vast areas. Competing methodologies are much expensive and time-consuming.
Frattini P, Crosta G and Sosio R (2009), "Approaches for defining thresholds and return periods for rainfall-triggered shallow landslides", Hydrol. Process.. Vol. 23(10), pp. 1444-1460. John Wiley & Sons, Ltd..
Abstract: Probabilistic thresholds for triggering shallow landslides by rainfall are developed using two approaches: a logistic regression model and Iverson's physically based model. Both approaches are applied to a 180 km2 area in northern Italy. For the physically based model a Monte Carlo approach is used to obtain probabilities of slope failure associated with differing combinations of rainfall intensity and duration as well as differing topographic settings. For the logistic regression model hourly and daily rainfall data and split-sample testing are used to explore the effect of antecedent rainfall on triggering thresholds. It is demonstrated that both the statistical and physically based models provide stochastic thresholds that express the probability of landslide triggering. The resulting thresholds are comparable, even though the two approaches are conceptually different. The physically based model also provides an estimate of the percentage of potentially unstable areas in which failure can be triggered with a certain probability. The return period of rainfall responsible for landslide triggering is studied by using a Gumbel scaling model of rainfall intensity–duration–frequency curves. It is demonstrated that antecedent rainfall must be taken into account in landslide forecasting, and a method is proposed to correct the rainfall return period by filtering the rainfall maxima with a fixed threshold of antecedent rainfall. This correction produces an increase of the return periods, especially for rainstorms of short duration. Copyright © 2009 John Wiley & Sons, Ltd.
Frei C (2006), "Eine Länder übergreifende Niederschlagsanalyse zum August Hochwasser 2005. Ergänzung zu Arbeitsbericht 211. Arbeitsberichte der MeteoSchweiz, 213, S. 10."
Frei C and Schär C (1998), "A precipitation climatology of the Alps from high-resolution rain-gauge observations", International Journal of Climatology. Vol. 18(8), pp. 873-900.
Frei M (2009), "Validation of a new approach to determine vegetation effects on superficial soil movement". Thesis at: ETH Zürich.
Abstract: Soil bioengineering methods are applied to minimize slope erosion. They are considered to be environmentally compatible and blend-in with the natural scenery. However, in contrast to slope stability calculations carried out using well proven geotechnical engineering approaches, the effectiveness of soil bioengineering methods is more difficult to determine. Therefore, a new concept was developed at the WSL to quantify the contribution of vegetation to soil stability. In contrast to traditional methods, the new concept assigns vegetation effects to a friction angle term (of a soil strength equation) using the soil density as a temporary reference term.
To investigate the new concept, three hypotheses were formulated: H1 The water-stability of aggregates and the soil density are (positively) correlated. H2 Soil samples with vegetation have a water-stability of aggregates equivalent to samples of higher density without vegetation. H3 The difference of density of samples in H2 is (positively) correlated with the shear strength. The investigation was performed with cylindrical soil samples that were all treated differently. The first and the fourth treatment consisted of pure soil samples, while the samples of the second and the third treatment were planted with alder. Additionally, the samples of the third and the fourth treatment were inoculated with a mycorrhizal fungus. All samples were maintained in a greenhouse for 24 weeks, before part of the samples were used for aggregate stability tests. To this end, the aggregate stability was determined applying a modified wet-sieving procedure. Additionally, the root length per sample volume and the number of mycorrhized root tips was determined. The remaining samples were used for undrained triaxial compression tests. The evaluation of the shear tests was performed applying two limiting criteria for failure. The first criterion was specified for the transition stage from an elastic- to a plastic sample behaviour (yielding), while the second criterion characterises a sample behaviour at nearly constant shear stress approaching failure.
Furthermore, generalized linear regression models were developed for the aggregate stability tests and the triaxial compression tests to determine those variables that had a significant influence on the response variables for aggregate stability and shear strength, respectively. The results showed that unplanted and differently compacted samples had a good correlation between the dry unit weight and the aggregate stability. Furthermore, planted samples with roots colonised by mycorrhizal fungi showed values for aggregate stability equivalent to unplanted and heavily compacted samples. The triaxial compression test, on the other hand, showed that the planted samples achieved equivalent friction angles to unplanted samples, but already at a lower dry unit weight. Furthermore, no cohesion was found, either for the planted samples or for the unplanted samples, and both treatments did not differ with regard to axial strain. Finally, the modelling showed for aggregate stability tests and triaxial tests that the fitted values represented the experimental data well.
The investigation confirms that the hypotheses can be validated by the experimental data. However, further investigations are required to quantify the (more general scope) of the soil-root compound system. In particular, tests with undisturbed horizontal root growth and plant-fungi systems that harmonize well would deliver promising results for further refinements of the new concept.
Freppaz M, Godone D, Filippa G, Maggioni M, Lunardi S, Williams MW and Zanini E (2010), "Soil Erosion Caused by Snow Avalanches: a Case Study in the Aosta Valley (NW Italy)", Arctic Antarctic and Alpine Research., November, 2010. Vol. 42(4), pp. 412-421.
Abstract: Snow avalanches can exert considerable erosive forces on soils. If a snow avalanche flows directly over bare ground, basal shear forces may scrape away and entrain soil. Soil material entrained by the avalanche is transported to the deposition zone, changing the chemical composition of the soils and potentially contributing to unique landforms. The quantity of soil material eroded and accumulated depends on avalanche characteristics and on morphological features, as well as soil properties and vegetation cover.
We monitored a channeled avalanche path in the Aosta Valley of NW Italy in order to assess the contribution of avalanche debris to the formation of soils in the runout zone. Sediment concentration estimates and measurements of the avalanche deposit volumes were used to estimate the total sediment load. The collected sediments were separated into fine sediments (,2 mm) and large (.2 mm) organic and mineral fractions. Results, obtained from the winter seasons of 2006, 2007, and 2008, showed that the amount of sediment deposited on the preexistent soil at the foot of the avalanche path was mainly the fine sediments fraction. The total carbon and nitrogen content in the fine sediment fraction ranged respectively from 6.6 to 9.0% and 0.37 to 0.42%. The total sediment load transported out of the 3.5 km2 basin was estimated to be 7585 kg in 2006, 27,115 kg in 2007, and 2323 kg in 2008. This mass transport resulted in basin averaged denudation rates ranging from 0.67 g m22 event21 in 2008 to 7.77 g m22 event21 in 2007. Annual accumulation in the runout zone was 240 Mg ha21 in 2006, 38 Mg ha21 in 2007 and 10 Mg ha21 in 2008. The inorganic N concentration of the snow in the runout zone was significantly greater than in the starting zone and was correlated with the organic fraction accumulated by the avalanche.
By redistributing snow, avalanches not only redistribute water but also nutrients that can be available for plants in the growing season. Moreover, avalanche paths are places where soil accumulates in some areas and erodes in others, contributing to potentially unique pedo-environmental conditions.
Frick E, Steffen B and Kienholz H (2004), "Gerinne-, Böschungs-, und Hangtypen in Wildbächen – Entwurf für ein praxistaugliches Verfahren zur Abschätzung der Feststofflieferung", In Proc. of the X International Congress Interpraevent 2004, Riva del Garda. Riva del Garda Vol. 7, pp. 83-94.
Abstract: Mit Hilfe eines Sets von Gerinnesohlen- und Böschungstypen wird ein Verfahren entwickelt, das der rationellen Abschätzung der Feststofflieferung von Wildbächen im Gelände dienen soll.
Je nach Grösse und Zugänglichkeit soll die Abschätzung im einzelnen Wildbach durch eine erfahrene Fachperson in einem oder wenigen Tagen erfolgen können, nachdem die notwendigen Vorabklärungen durchgeführt worden sind (allg. Charakter des Baches, Abflussverhältnisse, Aufzeichnungen früherer Ereignisse, Murfähigkeit, usw.).
Das Beurteilungsverfahren basiert auf einer Einteilung des Baches in mehr oder weniger homogene Abschnitte von Gerinne-, Böschungs- und Hangbereichen. Diesen Abschnitten werden in einer mehrstufigen Abfolge definierte Prozesstypen und Aktivitätsstufen zugeordnet. Prozessspezifisch werden dann mögliche Feststofflieferungen abgeschätzt. Abschliessend wird die Feststoffbilanz für die betrachteten Abschnitte und zusammenfassend für den gesamten Wildbach erstellt.
Die Abschätzung der Geschiebelieferung aus Hängen und Böschungen auf der Basis von Typisierungen wurde in verschiedenartigen Wildbächen getestet; die Methodik ist vielversprechend bezüglich Effizienz sowie Qualität und Nachvollziehbarkeit der Resultate. Noch nicht ausgereift und Gegenstand laufender Projekte ist dagegen der Weg über eine Typisierung im Gerinnesohlenbereich.
Friebe J (2004), "Zur Geologie Vorarlbergs – eine Einführung unter besonderer Berücksichtigung verkarstungsfähiger Gesteine", Vorarlberger Naturschau - forschen und entdecken. Vol. 15, pp. 19-39.
Friedel S, Thielen A and Springman SM (2006), "Investigation of a slope endangered by rainfall-induced landslides using 3D resistivity tomography and geotechnical testing", Journal of Applied Geophysics., October, 2006. Vol. 60(2), pp. 100-114.
Abstract: Rainfall-induced landslides pose a common problem in areas with slopes steeper than the friction angle of the soil. A series of such landslides in North Switzerland inspired a detailed geophysical and geotechnical site investigation prior to a monitoring experiment. High-resolution 2D and 3D electrical resistivity tomography (ERT) was used to derive a detailed subsurface image, which was verified by direct penetration tests, boreholes and laboratory analysis of soil samples with respect to grain size distribution and plasticity. Resolution analysis of ERT configurations proved a combination of Wenner-, Schlumberger- and Dipole-Dipole data to be a reasonable compromise between measurement time and model accuracy. Furthermore, a statistical approach to reducing subjectivity in the interpretation of 3D resistivity models is suggested. Applying this classification scheme to field data yields a model in very good agreement with the geotechnical model. The 3D resistivity model is then interpreted quantitatively using laboratory data and a constitutive relation accounting for clay and silt contents. The dominant influence of saturation on resistivity predicted by this model is confirmed and exemplified during repeated surveys in a dry and a wet period. In wet summer 2004, a silty sand layer of high water saturation is confined between two less permeable layers, the sandstone bedrock below and a clayey sand layer on top. This layer may locally form an aquifer, which becomes rapidly saturated during heavy rainfalls and contributes to the risk of failure. The combined ERT and geotechnical survey helped to optimize the design of the forthcoming monitoring experiment and may be used as a guideline for the investigation of similar slope conditions. (C) 2006 Elsevier B.V All rights reserved.
Fröhlich C and Mettenleiter M (2004), "Terrestrial laser scanning – New perspectives in 3D surveying", International Archives of Photogrammetry, Remote Sensing, and Spatial Information Sciences. Vol. XXXVI-8/W2, pp. 7-13.
Abstract: Laser scanners are used more and more as surveying instruments for various applications. With the advance of high precision systems, capable of working in most real world environments under a variety of conditions, numerous applications have opened up. In the field of surveying laser scanners open up a new dimension with data capturing. Different industrial sectors require precise data of the environment in order to be able to have a as-build documentation of the facility. Especially as build documentation of plants (automotive, chemical, pharmaceutical etc.) has become a very sensitive and important new segment, as companies need to document their facilities. This is a basic requirement to plan and evaluate emergency situations (evacuation scenarios etc.) but also for simulation purposes of specific manufacturing cycles (car assembly etc.) as well as design studies. Having the environment in 3D as a CAD model (“digital factory”) open up design studies without changing anything in the real environment and therefore causing no down time of production lines.
This paper reports about several systems and physical technologies used for measuring distances and presents several products available in this area. Furthermore it presents technical specifications of different systems and summarises with a comparison of achievable results.
Fuhrer J, Beniston M, Fischlin A, Frei C, Goyette S, Jasper K and Pfister C (2006), "Climate risks and their impact on agriculture and forests in Switzerland", Climatic Change., November, 2006. Vol. 79(1-2), pp. 79-102.
Abstract: There is growing evidence that, as a result of global climate change, some of the most severe weather events could become more frequent in Europe over the next 50 to 100 years. The paper aims to (i) describe observed trends and scenarios for summer heat waves, windstorms and heavy precipitation, based on results from simulations with global circulation models, regional climate models, and other downscaling procedures, and (ii) discuss potential impacts on agricultural systems and forests in Switzerland. Trends and scenarios project more frequent heavy precipitation during winter corresponding, for example, to a three-fold increase in the exceedance of today's 15-year extreme values by the end of the 21st century. This increases the risk of large-scale flooding and loss of topsoil due to erosion. In contrast, constraints in agricultural practice due to waterlogged soils may become less in a warmer climate. In summer, the most remarkable trend is a decrease in the frequency of wet days, and shorter return times of heat waves and droughts. This increases the risk of losses of crop yield and forage quality. In forests, the more frequent occurrence of dry years may accelerate the replacement of sensitive tree species and reduce carbon stocks, and the projected slight increase in the frequency of extreme storms by the end of the century could increase the risk of windthrow. Some possible measures to maintain goods and services of agricultural and forest ecosystems are mentioned, but it is suggested that more frequent extremes may have more severe consequences than progressive changes in means. In order to effectively decrease the risk for social and economic impacts, long-term adaptive strategies in agriculture and silviculture, investments for prevention, and new insurance concepts seem necessary.
Gabet EJ and Mudd SM (2006), "The mobilization of debris flows from shallow landslides", Geomorphology., March, 2006. Vol. 74(1-4), pp. 207-218. Elsevier Science Bv.
Abstract: According to critical state theory, a soil will approach a critical void ratio during shear such that loose soils contract and dense soils dilate. Theory indicates that failing soils must be loose to generate the pore pressures needed for the mobilization of debris flows. Previously published results from large-scale experiments have also suggested that soils must be initially loose to fail as debris flows. In this contribution, this mechanism for soil liquefaction is tested in the field through observations and geotechnical analysis of soils that failed during a large storm in central California. Surprisingly, we find that the debris flows mobilized from soils that were initially dense. In addition, we find that the potential for debris flow mobilization was strongly linked to the fines/ sand ratio. We present results from a numerical model that indicate that, as dilational soils approach the critical void ratio, the arresting effect of negative pore pressures generated by dilation is greatly reduced, leading to a rapid increase in basal pore pressure and rapid downslope acceleration. In addition, the model results suggest that the downslope displacement required to reach the critical state porosity in a dilative soil will be on the order of 0.1 to 1 m. Because the rate of the approach to critical state is fundamentally a function of the hydraulic conductivity of the soil, sandy soils will approach critical state much more rapidly than clay-rich soils. (c) 2005 Elsevier B.V. All rights reserved.
Galli M, Ardizzone F, Cardinali M, Guzzetti F and Reichenbach P (2008), "Comparing landslide inventory maps", Geomorphology., February, 2008. Vol. 94(3-4), pp. 268-289.
Abstract: Landslide inventory maps are effective and easily understandable products for both experts, such as geomorphologists, and for non experts, including decision-makers, planners, and civil defense managers. Landslide inventories are essential to understand the evolution of landscapes, and to ascertain landslide susceptibility and hazard. Despite landslide maps being compiled every year in the world at different scales, limited efforts are made to critically compare landslide maps prepared using different techniques or by different investigators. Based on the experience gained in 20 years of landslide mapping in Italy, and on the limited literature on landslide inventory assessment, we propose a general framework for the quantitative comparison of landslide inventory maps. To test the proposed framework we exploit three inventory maps. The first map is a reconnaissance landslide inventory prepared for the Umbria region, in central Italy. The second map is a detailed geomorphological landslide map, also prepared for the Umbria region. The third map is a multi-temporal landslide inventory compiled for the Collazzone area, in central Umbria. Results of the experiment allow for establishing how well the individual inventories describe the location, type and abundance of landslides, to what extent the landslide maps can be used to determine the frequency-area statistics of the slope failures, and the significance of the inventory maps as predictors of landslide susceptibility. We further use the results obtained in the Collazzone area to estimate the quality and completeness of the two regional landslide inventory maps, and to outline general advantages and limitations of the techniques used to complete the inventories. (c) 2007 Elsevier B.V. All rights reserved.
Gamper S and Tasser E (2002), "Interdisciplinary Mountain Research" Berlin , pp. 180-191. Blackwell Wiss.-Ver..
Abstract: Due to the ongoing structural changes in agriculture and forestry and the related economic challenges and restraints, the Alpine region has also suffered a process of abandonment of unfavourably situated areas and intensification of favoured areas. Especially mountain grasslands and pastures are affected by this trend towards extensification and abandonment. The aim of this work is to analyse how management-induced (mowing, fertilisation, and abandonment) vegetation changes effect the mass and the chemical properties of the O-horizon and the resulting changes in the A-horizon (0-10 cm). Mowing has a strong influence on the vegetation composition, on the litter quality, and on litter decomposition. Fertilisation results in alterations of the composition of vegetation; that is, a strong increase in grass and herbs, and a decrease in lignified species. Moreover it induces a high increase in phytomass, an increase in litter decomposition, and it has direct positive and negative effects on the nutrient balance of the O-horizon. Abandonment influences the correlations between the vegetation, O-horizon, and A-horizon in many ways. Litter quality decreases because of a decrease in herbaceous litter components in favour of lignified plant parts. With abandonment litter quantity (mass) increases and litter decomposition decreases, resulting in direct changes in the chemical properties of the A-horizon.
Gamper SM, Tasser E and Tappeiner U (2007), "Short-time effects of land-use changes on O-horizon in subalpine grasslands", Plant and Soil., October, 2007. Vol. 299(1-2), pp. 101-115.
Abstract: Due to economic needs, a process of abandonment of unfavourably situated areas and intensified cultivation on favoured areas has taken place in the alpine region. This abandonment not only means the loss of a cultural landscape based on centuries of care but also interference with an established ecological balance. We wanted to investigate the impact of land-use, such as mowing, fertilisation and irrigation and the effects of abandonment on the O-horizon type, quantity and quality. Therefore, we selected areas with different types of land use but with equivalent site conditions in the Passeier Valley (Bolzano-South Tyrol province) for investigation. The areas studied were as follows: an organically fertilised and irrigated, intensively managed hay meadow mown once a year; an organically fertilised, intensively managed hay meadow mown once a year; a lightly managed hay meadow mown every second year; a lightly managed hay meadow mown every 3-4 years; an area densely covered with dwarf shrubs abandoned 10 years ago; and a reforested area abandoned 30 years ago. These selected areas represent different intensities of land use or stages of succession. On these areas, vegetation, phytomass, litter quantity, humus type, O-horizon quantity, litter decomposition and C and N storage, were analysed in detail. Abandonment causes the percentage of coverage with grasses and herbs to decrease from 100 to 10%, while lignified species increase from 0 to 90%. This leads to growth of the phytomass pools, which in turn causes an increase in the annual litter quantity (from 117 to 525 g m(-2)). Significant changes in litter quality in the case of reduced use or abandonment increases the litter's resistance to decomposition, decreasing overall decomposition. Litter quantity and quality then have a significant impact on the O-horizon quantity. This increases strongly with decreasing intensity of land use or longer times since abandonment (115-1,180 g m(-2)). This leads to a significant increase of C and N storage and a change in O-horizon type ranging from no definite O-horizon or mull O-horizons on regularly used areas to moder on abandoned areas.
Garcia-Ruiz JM, Begueria S, Carlos Alatorre L and Puigdefabregas J (2010), "Land cover changes and shallow landsliding in the Spanish Pyrenees", Geomorphology., December, 2010. Vol. 124(3-4), pp. Int Assoc Geomorphol.
Abstract: This study investigated the characteristics, triggering factors, and spatial distribution of shallow landslides in relation to historical deforestation in the sub-alpine belt of the Pyrenees, particularly in the flysch sector. Shallow landslides in this area occur on straight and concave slopes, mainly covered by mesophyte grasslands, and contribute substantially to soil erosion and landscape deterioration. The investigated landslides were variable in shape and size, although common features included delimitation by a scar or semi-circular crown (averaging 32 m long x 10.15 m wide) and a tongue with a lobe at the foot of the scar area. The sliding surface coincided with the zone of contact of the C soil horizon with the bedrock, although in 13% of the cases the sliding surface occurred within the soil. The frontal lobes frequently trigger new landslides because of water accumulation and instability, resulting in a succession of interconnected landslides that can attain 100-200 m in length. Slope gradient appeared to be the most important factor correlated with shallow landslides. Thus, with slopes >30 degrees the soil was unstable and tended to slide even in dry conditions, whereas with slopes <15 degrees the soil was stable even under saturated conditions; shallow landslides were consequently concentrated on slopes between 15 degrees and 30 degrees. Rapid deforestation of the sub-alpine belt during the Middle and Modern Ages caused a sudden increase in hillslope instability. The studied landslides occurred only on deforested, grassland-covered hillslopes, and not in adjacent forested areas. Therefore, deforestation is considered to be a major factor contributing to shallow landslides, because of changes in soil hydrology and reduced soil strength as a consequence of decreased root cohesion, mainly coinciding with snowmelt and large rainstorms. (C) 2010 Elsevier B.V. All rights reserved.
Garcia-Ruiz JM, Lasanta T, RuizFlano P, Ortigosa L, White S, Gonzalez C and Marti C (1996), "Land-use changes and sustainable development in mountain areas: A case study in the Spanish Pyrenees", Landscape Ecology., October, 1996. Vol. 11(5), pp. 267-277.
Abstract: Land-use changes affecting Mediterranean mountains represent the intensification of use in valley bottoms, accompanied by land-use conflicts, and a generalized abandonment of the hillslopes, which in the past were perfectly integrated in the system of land management. Farmland abandonment, reforestation, diminution of the livestock pressure and substitution of cereal crops by meadows are the most outstanding features of the recent land-use changes. The question is whether the new spatial organisation is in accordance with a longterm policy of sustainable development in mountain areas. The results obtained confirm that farmland abandonment on steep slopes - and the resulting colonization of old fields by a dense shrub cover - and afforestation contribute to control both soil erosion and surface runoff. As a result some of the most important rivers and alluvial fans have recently stabilized their sedimentary structures.
Gardner RH, Milne BT, Turner MG and O'Neill RV (1987), "Neutral models for the analysis of broad-scale landscape pattern", Landscape Ecology., July, 1987. Vol. 1(1), pp. 19-28.
Abstract: The relationship between a landscape process and observed patterns can be rigorously tested only if the expected pattern in the absence of the process is known. We used methods derived from percolation theory to construct neutral landscape models, i.e., models lacking effects due to topography, contagion, disturbance history, and related ecological processes. This paper analyzes the patterns generated by these models, and compares the results with observed landscape patterns. The analysis shows that number, size, and shape of patches changes as a function of p, the fraction of the landscape occupied by the. habitat type of interest, and m, the linear dimension of the map. The adaptation of percolation theory to finite scales provides a baseline for statistical comparison with landscape data. When USGS land use data (LUDA) maps are compared to random maps produced by percolation models, significant differences in the number, size distribution, and the area/perimeter (fractal dimension) indices of patches were found. These results make it possible to define the appropriate scales at which disturbance and landscape processes interact to affect landscape patterns.
Gassman PW, Reyes MR, Green CH and Arnold JG (2007), "The soil and water assessment tool: historical development, applications, and future research directions" Center for Agricultural and Rural Development, Iowa State University.
Gellrich M, Baur P, Koch B and Zimmermann NE (2007), "Agricultural land abandonment and natural forest re-growth in the Swiss mountains: A spatially explicit economic analysis", Agriculture Ecosystems & Environment., January, 2007. Vol. 118(1-4), pp. 93-108.
Abstract: Natural forest re-growth reflects a decline in traditional agricultural practices that can be observed worldwide. Over the last few decades, natural forest re-growth has replaced much of the agricultural land in the Swiss mountains. This is a region where forms of traditional cultivation have preserved unique landscapes and habitats of high ecological value. This study aimed to characterise the locations in the Swiss mountains where agricultural land has been abandoned and overgrown by trees and bushes. Therefore, multivariate statistical models based on geo-physical and socio-economic variables were developed. Land-use change data were taken from two nationwide land-use surveys carried out in the 1980s and 1990s. In order to obtain reliable models, neighbourhood effects and the group structure in our data were accounted for. For the latter a robust estimation technique known as cluster-adjustment was used. Results show that forest re-growth is largely restricted to former alpine pastures, land with grass and scrub vegetation and agricultural land with groups of trees at mid to high altitudes, steep slopes, stony ground and a low temperature sum. Some relationships were not as expected, e.g. many of the new forest areas were found to be relatively close to roads. A new finding from this study was that forest re-growth is largely restricted to regions with immigration, higher proportions of part-time farms as opposed to full-time farms and high farm abandonment rates. By accounting for neighbourhood effects, the model fit was improved. The considerable residual deviance of the models was interpreted as the result of undetected local characteristics, such as poor water availability, small-scaled topographic peculiarities (e.g. small trenches, stonewalls, soil damages by cattle) and the individual's motivation to abandon or maintain cultivation. The conclusion made was that general policy measures for the whole mountain area are not suitable for the prevention of land abandonment and forest re-growth, and that policy measures must pay more attention to local characteristics and needs. (c) 2006 Elsevier B.V All rights reserved.
Gellrich M, Baur P and Zimmermann NE (2007), "Natural forest regrowth as a proxy variable for agricultural land abandonment in the Swiss mountains: a spatial statistical model based on geophysical and socio-economic variables", Environmental Modeling & Assessment., November, 2007. Vol. 12(4), pp. 269-278.
Abstract: In many European mountain regions, natural forest regrowth on abandoned agricultural land and the related consequences for the environment are issues of increasing concern. We developed a spatial statistical model based on multiple geophysical and socio-economic variables to investigate the pattern of natural forest regrowth in the Swiss mountain area between the 1980s and 1990s. Results show that forest regrowth occurred primarily in areas with low temperature sum, intermediate steepness and soil stoniness as well as close to forest edges and relatively close to roads. Model results suggest that regions with weak labor markets are favored in terms of land abandonment and forest regrowth. We could not find an effect of population change on land abandonment and forest regrowth. Therefore, we conclude that decision makers should consider non-linearities in the pattern of forest regrowth and the fact that labor markets have an effect on land abandonment and forest regrowth when designing measures to prevent agricultural land abandonment and natural forest regrowth in the Swiss mountains.
Gellrich M and Zimmermann NE (2007), "Investigating the regional-scale pattern of agricultural land abandonment in the Swiss mountains: A spatial statistical modelling approach ", Landscape and Urban Planning . Vol. 79(1), pp. 65 - 76.
Abstract: In many European mountain regions, agricultural land abandonment and the related consequences for the environment are issues of increasing concern. During the last few decades, natural forest re-growth has steadily replaced agricultural land in the Swiss mountains. This is a region where forms of traditional cultivation have preserved unique landscapes and habitats of high ecological value. The aim of this study was to investigate the recent regional-scale pattern of agricultural land abandonment, as indicated by forest re-growth, in the Swiss mountains. For this, we developed multivariate spatial statistical models on the basis of mountain-wide land-use change data, evaluated between the 1980s and 1990s, and selected geo-physical and socio-economic variables. Results show that regions with shallow soils, steep slopes and under-developed road infrastructure were favoured in terms of land abandonment and forest re-growth. These regions were also characterised by low proportions of full-time farms. In some regions, strong labour markets were related to higher abandonment rates, but this is not a general trend in Swiss mountainous regions. We found no relationship between land abandonment and migration, which contrasts with findings in other European mountain regions. One model suggests a spatial ‘spillover’ effect, causing similar abandonment rates in adjacent regions, although this could not be proven in this study. We conclude that decision-makers should consider non-linearity in the pattern of land abandonment and the fact that part-time farming is related to land abandonment when designing measures to react to land abandonment and its consequences.
Geneletti D and Gorte BGH (2003), "A method for object-oriented land cover classification combining Landsat TM data and aerial photographs", International Journal of Remote Sensing., March, 2003. Vol. 24(6), pp. 1273-1286.
Abstract: Object-oriented classification techniques based on image segmentation are gaining interest as methods for producing output maps directly storable into Geophysical Information System (GIS) databases. A limitation in efficiently applying image segmentation is often represented by the spatial resolution of the image. This contribution proposes a method for overcoming this problem, based on the integrated use of images of different resolution. A high-resolution black and white (b/w) orthophoto and a subscene of a Landsat Thematic Mapper (TM) image have been used to obtain an object-oriented classification of the land cover of a study area in northern Italy. The method consists of a sequential application of segmentation and classification techniques. First, the TM image was classified using the maximum likelihood classifier and additional empirical rules. Subsequently, the orthophoto was segmented by applying a region-based segmentation algorithm. Finally, the classification of the segmented images was performed using as a reference the TM image previously classified. The resulting land cover map was tested for accuracy and the results are dicusssed.
Gerber W and Böll A (1993), "Massnahmen zum Schutz gegen Rutschungen und Steinschlag", In Naturgefahren. Forum für Wissen 1993. WSL.
Abstract: Menschen haben seit jeher Massnahmen zum Schutz vor Naturgefahren ergriffen. Während in früheren Jahrhunderten ein Ausweichen in weniger gefährdete Gebietemöglich war, werden heute aktive Massnahmen zur Einschränkung der gefährdeten Gebiete gefordert. Im folgenden wird auf Rutschungs- und Steinschlagprozesse eingegangen, und ihr Einfluss auf die entsprechenden Massnahmen wird näher betrachtet.
Gessler P, Pike R, MacMillan R, Hengl T and Reuter H (2008), "The Future of Geomorphometry", In Developments in Soil Science. Vol. 33 Elsevier.
Ghuffar S, Szekely B, Roncat A and Pfeifer N (2013), "Landslide Displacement Monitoring Using 3D Range Flow on Airborne and Terrestrial LiDAR Data", Remote Sensing. Vol. 5, pp. 2720-2745.
Abstract: An active landslide in Doren, Austria, has been studied by multitemporal airborne and terrestrial laser scanning from 2003 to 2012. To evaluate the changes, we have determined the 3D motion using the range flow algorithm, an established method in computer vision, but not yet used for studying landslides. The generated digital terrain models are the input for motion estimation; the range flow algorithm has been combined with the coarse-to-fine resolution concept and robust adjustment to be able to determine the various motions over the landslide. The algorithm yields fully automatic dense 3D motion vectors for the whole time series of the available data. We present reliability measures for determining the accuracy of the estimated motion vectors, based on the standard deviation of components. The differential motion pattern is mapped by the algorithm: parts of the landslide show displacements up to 10 m, whereas some parts do not change for several years. The results have also been compared to pointwise reference data acquired by independent geodetic measurements; reference data are in good agreement in most of the cases with the results of range flow algorithm; only some special points (e.g., reflectors fixed on trees) show considerably differing motions.
Giannecchini R (2006), "Relationship between rainfall and shallow landslides in the southern Apuan Alps (Italy)", Natural Hazards and Earth System Sciences. Vol. 6(3), pp. 357-364.
Abstract: The Apuan Alps region is one of the rainiest areas in Italy (more than 3000 mm/year), in which frequently heavy and concentrated rainfall occurs. This is particularly due to its geographical position and conformation: the Apuan chain is located along the northern Tuscan coast, close to the Ligurian Sea, and the main peaks reach almost 2000 m. In several cases, the storms that hit the area have triggered many shallow landslides (soil slip-debris flows), which exposed the population to serious risks (during the 19 June 1996 rainstorm about 1000 landslides were triggered and 14 people died). The assessment of the rainfall thresholds is very important in order to prepare efficient alarm systems in a region particularly dedicated to tour-ism and marble activities. With the aim of contributing to the landslide hazard evaluation of the southern Apuan Alps territory (upper Versilia area), a detailed analysis of the main pluviometric events was carried out. The data recorded at the main rain gauge of the area from 1975 to 2002 were analysed and compared with the occurrence of soil slips, in order to examine the relationship between soil slip initiation and rainfall. The most important rainstorms which triggered shallow landslides occurred in 1984, 1992, 1994, 1996, 1998 and 2000. Many attempts were made to obtain a possible correlation between rainfall parameters and the occurrence of soil slip phenomena and to identify the local rainfall threshold for triggering shallow landslides. A threshold for soil slip activity in terms of mean intensity, duration and mean annual precipitation (MAP) was defined for the study area. The thresholds obtained for the southern Apuan Alps were also compared with those proposed by other authors for several regions in the world. This emphasized the high value of the rain threshold for shallow landslide activity in the Apuan area. The high threshold is probably also linked to the high mean annual precipitation and to the high frequency of rainstorms.
Giannecchini R (2005), "Rainfall triggering soil slips in the southern Apuan Alps (Tuscany, Italy)", Advances in Geosciences. Vol. 2, pp. 21-24.
Abstract: The Apuan Alps are characterized by frequent heavy rainfall. In several cases this triggered many shallow landslides (soil slips). With the aim of contributing to the landslide hazard evaluation of the southern Apuan Alps (upper Versilian area), a detailed analysis of the main pluviometric events was carried out. Data recorded at the main raingauge of the area from 1975 to 2002 were analysed and compared with the occurrence of soil slips, in order to examine the relationship between soil slip initiation and rainfall. Some thresholds for soil slip-debris flow activity in terms of mean intensity, duration and mean annual precipitation (MAP) were defined for the study area.
Glade T (2003), "Landslide occurrence as a response to land use change: a review of evidence from New Zealand", Catena., April, 2003. Vol. 51(3-4), pp. 297-314.
Abstract: Vegetation cover is an important factor influencing the occurrence and movement of rainfall-triggered landslides, and changes to vegetation cover often result in modified landslide behaviour. However, it is difficult to relate the occurrence of landslides directly to variations in land use, especially in some European countries. In contrast, New Zealand provides a good opportunity to investigate geomorphic responses to anthropogenic land cover changes. Before European settlers first arrived in the 1840s, hilly regions were only marginally influenced by human activity. The Maoris, New Zealand's first settlers, lived largely on coastal plains or near lakes and rivers. They influenced general vegetation cover only through localized burning practices. In contrast, European settlers moved into the back country and converted extensive hill areas from native forest and bush to pasture. This reduced the strength of the regolith and rendered the slopes more susceptible to landslides. Pulses of natural sedimentation in the pre-European period have been related to volcanic activity, climatic variability, including changes in frequency of cyclonic storms and wind erosion and fluvial erosion following forest fires initiated either by volcanic eruptions or lightning strikes. Since European deforestation began, sediment production has largely been determined by landslide events. On unstable slopes, thousands of landslides were triggered by high-magnitude/low-frequency climatic events during storms with estimated return periods in excess of 50 years. In contrast, low-magnitude/high-frequency rainfall events have caused gully and channel erosion. Examples from different parts of New Zealand indicate changes in sediment-generating processes following land use modifications. After deforestation, landslides have contributed significantly to sediment sequences in depositional basins such as lakes, swamps, estuaries, coastal wetlands and the nearshore and offshore zones of continental platforms. (C) 2002 Elsevier Science B.V. All rights reserved.
Glade T (1998), "Establishing the frequency and magnitude of landslide-triggering rainstorm events in New Zealand", Environmental Geology., August, 1998. Vol. 35(2-3), pp. European Geophys Soc.
Abstract: Landslide erosion has an established history in New Zealand. Some broad estimates of economic costs for short-term event damage, long-term landslide damage, and proactive measures are provided and compared on a national and international level. Frequency and magnitude analysis based on historical records of landslide-triggering rainstorms demonstrates that 1) landslides are a nationwide problem, 2) recognition and recording of these events is dependent on public awareness and therefore related to population distribution and extent of urbanized areas, and 3) deforestation increases the frequency of landslide events, but not necessarily the total magnitude of their impact. However, some regions such as Northland and Wellington in the North Island and Greymouth and North Otago in the South Island are more frequently and more strongly affected than others. Landslide occurrence in time and space, within representative study areas in Hawke's Bay, Wairarapa, and Wellington, is correlated with the climatic variable daily precipitation. Different regional hydrological thresholds for landslide triggering are established.
Glade T and Crozier M (1999), "Landslides in New Zealand: A selected Bibliography. School of Earth Science Research Report No.1, pp. 102."
Abstract: Research on landslides has a well established history in New Zealand. Since the beginning of this century, problems resulting from landslide occurrence have increased stadily. Despite the growing number of publications on landslide issues, only SELBY (1976) published a preliminary bibliography. SELBY‘s report summarises the major contribution in the field of mass movements until 1970. HARMSWORTH & PAGE (1991) undertook a literature search within the purpose of compiling information on landslide damaging rainstorms. A recent report on earthquake-triggered landslides with a volume >1,000,000 m3 is published by IGNS (1996). A landslide inventory comiling information on rainfall-triggered landslides is held at the Institute of Geography, Victoria University of Wellington. The latter data base contains only rainfall-triggered landslides and it became obvious that there was an equal need for a comprehensive bibliography of all accessible landslide references for New Zealand.
Glade T, Crozier M and Smith P (2000), "Applying Probability Determination to Refine Landslide-triggering Rainfall Thresholds Using an Empirical "Antecedent Daily Rainfall Model"", pure and applied geophysics. Vol. 157(6-8), pp. 1059-1079. Birkhäuser Verlag.
Abstract: Rainfall-triggered landslides constitute a serious hazard and an important geomorphic process in many parts of the world. Attempts have been made at various scales in a number of countries to investigate triggering conditions in order to identify patterns in behaviour and, ultimately, to define or calculate landslide-triggering rainfall thresholds. This study was carried out in three landslide-prone regions in the North Island of New Zealand. Regional landslide-triggering rainfall thresholds were calculated using an empirical ‘‘Antecedent Daily Rainfall Model.’’ In this model, first introduced by CROZIER and EYLES (1980), triggering rainfall conditions are represented by a combination of rainfall occurring in a period before the event (antecedent rainfall) and rainfall on the day of the event. A physically-based decay coefficient is derived for each region from the recessional behaviour of storm hydrographs and is used to produce an index for antecedent rainfall. Statistical techniques are employed to obtain the thresholds which best separate the rainfall conditions associated with landslide occurrence from those of non-occurrence or a given probability of occurrence.
The resultant regional models are able to represent the probability of occurrence of landsliding events on the basis of rainfall conditions. The calculated thresholds show regional differences in susceptibility of a given landscape to landslide-triggering rainfall. These differences relate to both the landslide database and the difference of existing physical conditions between the regions.
Glade T and Dikau R (2001), "Gravitative Massenbewegungen - vom Naturereignis zur Naturkatastrophe", Petermanns Geographische Mitteilungen. Vol. 145(6), pp. 42-53.
Abstract: Landslides are natural geomorphic processes. Volumes range tram cubicmeter to cubickilometer and occur with recurrence intervals of days to millenniums. Movement processes include toppies, falls, slides, flows and spreads at low or extremely rapid velocities. The terms natural hazard, natural risk and natural disasters are defined and compared with natural events. Different examples of large landslide events without catastrophic consequences are provided. In contrast are these events, which can be defined as natural disasters. The role of humans, who change a natural event to a natural hazard and which may lead to a natural disaster will be explored and highlighted in the context of landslides.
Glade T, Petschko H, Bell R, Bauer C, Granica K, Heiss G, Leopold P, Pomaroli G, Proske H and Schweigl J (2012), "Landslide Susceptibility Maps for Lower Austria - Methods and Challenges", In Proc. of the XII International Congress Interpraevent 2012, Grenoble. Grenoble / France
Glade T, Stark P and Dikau R (2005), "Determination of potential landslide shear plane depth using seismic refraction - a case study in Rheinhessen, Germany", Bulletin of Engineering Geology and the Environment., May, 2005. Vol. 64(2), pp. 151-158.
Abstract: Landslides on the Rheinhessen cuesta are not only a natural component of slope evolution but also have been influenced by anthropogenic activities such as viniculture. Single landslides as well as the regional occurrence of hundreds of mass movements have a direct and indirect effect on the environment and cause high economic loss. This study analyses a regionally characteristic landslide, DROM 9, to establish the potential for the use of seismic refraction to determine the change of substrate below the ground surface. In Rheinhessen, landslides commonly occur as shallow translational features in depressions that were probably created as Pleistocene valleys. Seismic field data have been analysed using the "intercept technique" and the "generalised reciprocal method". The depth of the substrate and the divisions within it were confirmed by boreholes. With this information, it is possible to develop a structural model of the subsurface, which leads to a better understanding of landslide kinematics.
Glenn NF, Streutker DR, Chadwick DJ, Thackray GD and Dorsch SJ (2006), "Analysis of LiDAR-derived topographic information for characterizing and differentiating landslide morphology and activity", Geomorphology., January, 2006. Vol. 73(1-2), pp. 131-148.
Abstract: This study used airborne laser altimetry (LiDAR) to examine the Surface morphology of two canyon-rim landslides in southern Idaho. The high resolution topographic data were used to calculate surface roughness, slope, semivariance, and fractal dimension. These data were combined with historical movement data (Global Positioning Systems (GPS) and laser theodolite) and field observations for the currently active landslide, and the results Suggest that topographic elements are related to the material types and the type of local motion of the landslide. Weak, unconsolidated materials comprising the toe of the slide, which were heavily fractured and locally thrust upward, had relatively high surface roughness, high fractal dimension, and high vertical and lateral movement. The body of the slide, which predominantly moved laterally and consists mainly Of undisturbed, older canyon floor materials, had relatively lower surface roughness than the toe. The upper block, consisting of a down-droppcd section of the canyon rim that has remained largely intact, had a low Surface roughness on its upper surface and high surface roughness along fractures and on its west face (unrelated to landslide motion). The upper block also had a higher semivariance than the toe and body. The topographic data for a neighboring, older and larger landslide complex, which failed in 1937, are similarly used to understand surface morphology, as well as to compare to the morphology of the active landslide and to understand scale-dependent processes. The morphometric analyses demonstrate that the active landslide has a similar failure mechanism and is topographically more variable than the 1937 landslide, especially at scales > 20 m. Weathering and the larger scale processes of the 1937 slide are hypothesized to cause the lower semivariance values of the 1937 slide. At smaller scales (< 10 m) the topographic components of the two landslides have similar roughness and semivariance. Results demonstrate that high resolution topographic data have the potential to differentiate morphological components within a landslide and provide insight into the material type and activity of the slide. The analyses and results in this study would not have been possible with coarser scale digital elevation models (10-m DEM). This methodology is directly applicable to analyzing other geomorphic surfaces at appropriate scales, including glacial deposits and stream beds. (c) 2005 Elsevier B.V. All rights reserved.
Gobin A, Jones R, Kirkby M, Campling P, Govers G, Kosmas C and Gentile AR (2004), "Indicators for pan-European assessment and monitoring of soil erosion by water", Environmental Science & Policy. Vol. 7(1), pp. 25-38.
Abstract: Soil erosion forms a major threat to European soil resources. Although soil is a vital and largely non-renewable resource, it has not been the subject of comprehensive EU action so far. A thematic strategy for soil protection, which recognises soil erosion as one of the major threats, has currently been placed high on Europe's political Agenda. Assessing and monitoring soil erosion is needed to evaluate the impact of, inter alia, agricultural and land use policies in Europe. The driving force-pressure-state-impact-response (DPSIR) policy framework, applied to soil erosion, is reviewed and suggestions for improvements are proposed. The agri-environmental indicators (AEIs) of soil erosion are discussed in relation to data availability, policy requirements and analytical soundness. We propose a reviewed framework and a set of soil erosion indicators that can be objectively calculated, validated against measurements or observations and evaluated by experts. (C) 2003 Published by Elsevier Ltd.
Godt JW, Baum RL and Chleborad AF (2006), "Rainfall characteristics for shallow landsliding in Seattle, Washington, USA", Earth Surface Processes and Landforms., January, 2006. Vol. 31(1), pp. 97-110.
Abstract: Shallow landsliding in the Seattle, Washington, area, has caused the occasional loss of human life and millions of dollars in damage to property. The effective management of the hazard requires an understanding of the rainfall conditions that result in landslides. We present an empirical approach to quantify the antecedent moisture conditions and rainstorm intensity and duration that have triggered shallow landsliding using 25 years of hourly rainfall data and a complementary record of landslide occurrence. Our approach combines a simple water balance to estimate the antecedent moisture conditions of hillslope materials and a rainfall intensity-duration threshold to identify periods when shallow landsliding can be expected. The water balance is calibrated with field-monitoring data and combined with the rainfall intensity-duration threshold using a decision tree. Results are cast in terms of a hypothetical landslide warning system. Two widespread landslide events are correctly identified by the warning scheme; however, it is less accurate for more isolated landsliding. Copyright (c) 2005 John Wiley & Sons, Ltd.
Goetz JN, Guthrie RH and Brenning A (2011), "Integrating physical and empirical landslide susceptibility models using generalized additive models ", Geomorphology . Vol. 129(3–4), pp. 376-386.
Abstract: Physically based models are commonly used as an integral step in landslide hazard assessment. Geomorphic principles can be applied to a broad area, resulting in first order assessment of landslide susceptibility. New techniques are now available that may result in the increased accuracy of such models. We investigate the possibility to enhance landslide susceptibility modeling by integrating two physically-based landslide models, the Factor of Safety (FS) and the Shallow Stability model (SHALSTAB), with traditional empirical-statistical methods that utilize terrain attribute information derived from a digital elevation model and land use characteristics related to forest harvesting. The model performance is measured by the area under the receiver operating characteristic curve (AUROC) and sensitivity at 90% and 80% specificity both estimated by bootstrap resampling. Our study examines 278 landslide initiation points in the Klanawa Watershed located on Vancouver Island, British Columbia, Canada. We use a generalized additive model (GAM) and a logistic regression model (GLM) combining physical landslide models, terrain attributes and land use data, and GAMs and GLMs using only subsets of these variables. In this study, all empirical and combined physical–empirical models outperform the physically-based models, with GAMs often performing significantly better than GLMs. The strongest predictive performance is achieved by the GAMs using terrain attributes in combination with land use data. Variables representing physically-based models do not significantly improve the empirical models, but they may allow for a better physical interpretation of empirical models. Also, based on bootstrap variable-selection frequencies, land use data, FS, slope and plan/profile curvature are relatively the most important predictor variables.
Gokceoglu C and Sezer E (2009), "A statistical assessment on international landslide literature (1945-2008)", Landslides., December, 2009. Vol. 6(4), pp. 345-351.
Abstract: In the present study, the analysis of the international landslide literature is aimed. The landslide is perhaps one of the most complex natural phenomena. Also, due to landslides, a considerable amount of loss of lives and economic losses is encountered throughout the world. Although a vast amount of landslide papers is published in international journals, a statistical assessment on this literature is not encountered. For this reason, this study is performed. For the assessment of the international landslide literature, the Science Citation Index Expanded (WOS; Web of Science) published by Institute of Scientific Information (now Thomson Scientific), USA for the period 1945-2008, is considered. A total of 3,468 publications are found and this data is stored into Oracle XE database and queried by using Structured Query Language and Procedural Language/Structured Query Language. In the following stages, some statistical analyses are performed and the possible trends are discussed.
Gomez H and Kavzoglu T (2005), "Assessment of shallow landslide susceptibility using artificial neural networks in Jabonosa River Basin, Venezuela", Engineering Geology., April, 2005. Vol. 78(1-2), pp. 11-27. Elsevier Science Bv.
Abstract: Landslides represent one of the most morphodynamic processes that affect the steep lands, and may destroy croplands as well as urban and industrial development. Landslide risk analysis can help government agencies to select suitable locations for development schemes and plan mitigation measures in unstable landslide-prone areas. This study describes an approach for assessing the landslide risk potential, mainly for shallow landslides, with reference to Jabonosa river basin in the Venezuelan Andes using artificial neural networks (ANNs), specifically a Multilayer Perceptron with backpropagation learning algorithm. The approach developed uses a wide range of parameters of slope instability derived from digital elevation models (DEMs), remote sensing imagery and documentary data. Around 90% overall accuracy produced by the ANN technique were found promising for future studies in landslide susceptibility zonation. (c) 2004 Elsevier B.V. All rights reserved.
González A and Mayorga R (2004), "Thresholds for rainfall events that induce landslide in Colombia", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 349-355. Taylor & Francis.
Gorsevski PV, Gessler PE, Boll J, Elliot WJ and Foltz RB (2006), "Spatially and temporally distributed modeling of landslide susceptibility ", Geomorphology . Vol. 80(3–4), pp. 178 - 198.
Abstract: Mapping of landslide susceptibility in forested watersheds is important for management decisions. In forested watersheds, especially in mountainous areas, the spatial distribution of relevant parameters for landslide prediction is often unavailable. This paper presents a GIS-based modeling approach that includes representation of the uncertainty and variability inherent in parameters. In this approach, grid-based tools are used to integrate the Soil Moisture Routing (SMR) model and infinite slope model with probabilistic analysis. The SMR model is a daily water balance model that simulates the hydrology of forested watersheds by combining climate data, a digital elevation model, soil, and land use data. The infinite slope model is used for slope stability analysis and determining the factor of safety for a slope. Monte Carlo simulation is used to incorporate the variability of input parameters and account for uncertainties associated with the evaluation of landslide susceptibility. This integrated approach of dynamic slope stability analysis was applied to the 72-km2 Pete King watershed located in the Clearwater National Forest in north-central Idaho, USA, where landslides have occurred. A 30-year simulation was performed beginning with the existing vegetation covers that represented the watershed during the landslide year. Comparison of the GIS-based approach with existing models (FSmet and SHALSTAB) showed better precision of landslides based on the ratio of correctly identified landslides to susceptible areas. Analysis of landslide susceptibility showed that (1) the proportion of susceptible and non-susceptible cells changes spatially and temporally, (2) changed cells were a function of effective precipitation and soil storage amount, and (3) cell stability increased over time especially for clear-cut areas as root strength increased and vegetation transitioned to regenerated forest. Our modeling results showed that landslide susceptibility is strongly influenced by natural processes and human activities in space and time; while results from simulated outputs show the potential for decision-making in effective forest planning by using various management scenarios and controlling factors that influence landslide susceptibility. Such a process-based tool could be used to deal with real-dynamic systems to help decision-makers to answer complex landslide susceptibility questions.
Gorum T, Fan X, van Westen CJ, Huang RQ, Xu Q, Tang C and Wang G (2011), "Distribution pattern of earthquake-induced landslides triggered by the 12 May 2008 Wenchuan earthquake", Geomorphology., October, 2011. Vol. 133(3-4), pp. 152-167.
Abstract: This paper presents the preliminary results of an extensive study of the mapping the distribution of landslides triggered by the Wenchuan earthquake in Sichuan Province, China, on 12 May 2008. An extensive landslide interpretation was carried out using a large set of optical high resolution satellite images (e.g. ASTER, ALOS, Cartosat-1, SPOT-5 and IKONOS) as well as air photos for both the pre- and post-earthquake situation. Landslide scarps were mapped as points using multi-temporal visual image interpretation taking into account shape, tone, texture, pattern, elevation and ridge and valley orientation. Nearly 60,000 individual landslide scarps were mapped. The landslide distribution map was compared with the inventory map that was prepared directly after the earthquake, which contains about 11,000 individual landslide points, through the calculation of normalized landslide isopleths maps. Remarkable differences were observed, as the earlier inventory mapping did not consider the pre-earthquake situation and did not consider all individual landslides. As part of the landslide inventory, landslides were identified that had blocked the drainage and had formed landslide dams. The landslide distribution was compared with a number of aspects, such as the seismic parameters (distance to epicenter, distance to fault rupture, co-seismic fault geometry and co-seismic slip distribution), and geology. The most remarkable correlation found was with the co-seismic slip distribution and the fault geometry. Landslide distribution in the section of the fault that had mainly a thrust component with low angle fault plane was found to be much higher than the sections that had steeper fault angles and a major strike slip component. (C) 2011 Elsevier B.V. All rights reserved.
Goswami R, Mitchell NC and Brocklehurst SH (2011), "Distribution and causes of landslides in the eastern Peloritani of NE Sicily and western Aspromonte of SW Calabria, Italy", Geomorphology., September, 2011. Vol. 132(3-4), pp. 111-122.
Abstract: The Peloritani and Aspromonte areas are tectonically active mountainous regions of NE Sicily and SW Calabria, respectively, where landslides are the most common hillslope mass-wasting process. This study aims to elucidate the primary controls on the distribution and size of landslides in these two different landscapes. These regions, either side of the Messina Strait, have similar lithologies, but show different morphological characteristics in response to varied neo-tectonic activity and climate. Landslides were identified utilising aerial photographs and Landsat images. Frequency-area statistics were calculated to determine the length-scale of the most frequent interpretable landslides and compare our results with previous studies. The frequency-area power-law exponents (1.99 in Peloritani and 1.94 in Aspromonte) fall within the range of values that have been observed (2.0 +/- 0.5) in similar landscapes. The Peloritani Ridge, Sicily, has range-parallel normal fault segments with the majority of landslides occurring in their footwalls. There seems to be a strong coupling between tectonic activity and landslides, where slope instability is exacerbated by faulting, fracturing or jointing in otherwise low-permeability gneiss and granite bedrock. Conversely, in Aspromonte, Calabria, landslides are restricted to steep valley walls, and are absent from interfluves. This is because landslides are controlled by fluvial incision processes. These observations confirm a relationship between the spatial distribution of landslides and the processes controlling slope failures. (C) 2011 Elsevier BM. All rights reserved.
de Graaff LWS, de Jong MGG, Busnach T and Seijmonsbergen AC (2003), "Geomorphologische Studie Hinterer Bregenzerwald. Bericht an das Amt der Vorarlberger Landesregierung"
Grabherr G, Gottfried M and Pauli H (2007), "IGF-Forschungsberichte 1. Wien." , pp. 21-36. IGF (Institut für interdisziplinäre Gebirgsforschung).
Graf C, Böll A and Graf F (2003), "Pflanzen im Einsatz gegen Erosion und oberflächennahe Rutschungen", WSL-Merkbl. Prax.. Vol. 37, pp. 1-8.
Abstract: Naturgewalten haben die Menschen seit jeher gezwungen ihren Lebensraum zu schützen. Die frühen Siedler verwendeten dazu einfachste Methoden, welche beispielsweise ein Stützen oder Regulieren betroffener Geländeteile erlaubten. Dies geschah mit den vor Ort verfügbaren Baustoffen wie Steinen, Holz und Pflanzen. Der Einsatz von Pflanzen gegen Erosion und oberflächennahe Rutschungen hat sich seither laufend weiterentwickelt und in vielen verschiedenen Bauweisen bewährt. So zahlreich heute die Begriffe für das Verbauen mit Pflanzen sind (Lebendverbau, Grünverbau, Ingenieurbiologie, Eco-engineering, usw.) so unterschiedlich lauten die entsprechenden Definitionen. Eine davon stützt sich vornehmlich auf Prozesse ab und berücksichtigt neben den praktischen Aspekten auch neuste Erkenntnisse aus der Forschung. Im folgenden wird nur der Begriff «Ingenieurbiologie» verwendet.
Graham DJ, Reid I and Rice SP (2005), "Automated sizing of coarse-grained sediments: Image-processing procedures", Mathematical Geology., January, 2005. Vol. 37(1), pp. 1-28.
Abstract: This is the first in a pair of papers in which we present image-processing-based procedures for the measurement of fluvial gravels. The spatial and temporal resolution of surface grain-size characterization is constrained by the time-consuming and costly nature of traditional measurement techniques. Several groups have developed image-processing-based procedures, but none have demonstrated the transferability of these techniques between sites with different lithological, clast form and textural characteristics. Here we focus on image-processing procedures for identifying and measuring image objects (i.e. grains); the second paper examines the application of such procedures to the measurement of fluvially deposited gravels. Four image-segmentation procedures are developed, each having several internal parameters, giving a total of 416 permutations. These are executed on 39 images from three field sites at which the clasts have contrasting physical properties. The performance of each procedure is evaluated against a sample of manually digitized grains in the same images, by comparing three derived statistics. The results demonstrate that it is relatively straightforward to develop procedures that satisfactorily identify objects in any single image or a set of images with similar sedimentary characteristics. However, the optimal procedure is that which gives consistently good results across sites with dissimilar sedimentary characteristics. We show that neighborhood-based operations are the most powerful, and a morphological bottom-hat transform with a double threshold is optimal. It is demonstrated that its performance approaches that of the procedures giving the best results for individual sites. Overall, it out-performs previously published, or improvements to previously published, methods.
Graham DJ, Rice SP and Reid I (2005), "A transferable method for the automated grain sizing of river gravels", Water Resources Research., July, 2005. Vol. 41(7), pp. W07020.
Abstract: [ 1] The spatial and temporal resolution of surface grain-size characterization is constrained by the limitations of traditional measurement techniques. In this paper we present an extremely rapid image-processing- based procedure for the measurement of exposed fluvial gravels and other coarse-grained sediments, defining the steps required to minimize the errors in the derived grain-size distribution. This procedure differs significantly from those used previously. It is based around a robust object-detection algorithm that produces excellent results on images exhibiting a wide range of sedimentary conditions, crucially, without any user intervention or site-specific parameterization. The procedure is tested using a data set comprising 39 images from three rivers with contrasting grain lithology, shape, roundness, and packing configuration and representing a very wide range of textures. It is shown to perform more consistently than the best existing automated method, achieving a precision equivalent to that obtainable by Wolman sampling, but taking between one sixth and one twentieth of the time. The error in area-by-number grain-size distribution percentiles is typically less than 0.05 psi.
Gray DH (1995), "Influence of vegetation on the stability of slopes", In Proceedings of the International Conference on Vegetation and Slopes, Stabilisation, Protection and Ecology, University Museum, Oxford, 29-30 September 1994, Thomas Telford, London, 1 – 24..
Gray DH and Sotir RB (1996), "Biotechnical and soil bioengineering slope stabilization: a practical guide for erosion control" Wiley-Interscience.
Gregory J (1911), "The terms „Denudation“, „Erosion“, „Corrosion“ and „Corrasion“", The Geographical Journal. Vol. 37(2), pp. 189-195.
Abstract: PROFESSOR BONNEY'S Presidential Address to the British Association has directed attention to the relative importance of ice and water as geographical agents. The international discussion of the relative efficiency of the various processes that mould the surface of the Earth is handicapped by the development during recent years of different meanings in Europe and America for the chief terms used in the classification of these processes. The important terms "denudation," "erosion," " corrosion," and " corrasion " have become ambiguous.
Gritzner ML, Marcus WA, Aspinall R and Custer SG (2001), "Assessing landslide potential using GIS, soil wetness modeling and topographic attributes, Payette River, Idaho", Geomorphology., March, 2001. Vol. 37(1-2), pp. 149-165.
Abstract: This study utilizes GIS modeling to determine if the location of 559 landslides in the 875 km(2) catchment of the Middle Fork of the Payette River, Idaho can be predicted based on topographic attributes and a wetness index generated by the DYNWET model. Slope and elevation were significantly related to landslide occurrence at this landscape scale. Aspect was also retained as a variable for further analysis because, despite a non-significant chi-square relation to landslide occurrence, graphical analysis suggested a relation between aspect and mass wasting. Chi-square analysis indicated that plan and profile curvature, flow path length, upslope contributing area and the DYNWET-based moisture index were not significantly related to landsliding. A Bayesian probability model based on combinations of elevation, slope, aspect, and wetness indicates that elevation exhibits the closest relation to landsliding. followed by slope; but that neither aspect nor wetness index values help in prediction. The Bayesian probability model using elevation and slope generates a map of relative landslide risk that can be used to direct activities away from mass wasting prone areas, The association between elevation and landslides is perplexing but is perhaps due to the location of logging road at specific elevations (roads could not be included in the input data for analysis because they have not been adequately mapped). The lack of explanation provided by the DYNWET wetness index was also surprising and may be due to the 30-m digital elevation model (DEM) and the soils data having resolutions too coarse to adequately portray local variations key to mass wasting. We believe the inadequacy of data to drive the models is typical of the majority of catchment scale setting. For now, the ability of researchers to effectively model landscape scale landsliding is more limited by the type, resolution, and quality of available data than by the quality of the landslide models. (C) 2001 Elsevier Science B.V. All rights reserved.
Grottenthaler W and Laatsch W (1973), "Untersuchungen über den Hangabtrag im Lainbachtal bei Benediktbeuern", Forstwissenschaftliches Centralblatt. Vol. 92, pp. 1-19.
Abstract: In den nördlichen Randgebieten der Alpen findet man häufig periglaziale Talverfüllungen. KARL, DANZ und MANGELSDORF (1969) haben die Bedeutung dieser Lockermassen als Schuttherde und ihre Erosionsanfälligkeit eingehend dargestellt. Innerhalb Bayerns liegen die größten Schuttkörper dieser Art im Halblechgebiet und in verschiedenen Seitentälern von Ammer, Loisach, Isar und Traun. Alle diese Massen kamen während der Würmeiszeit in Stauseen zur Ablagerung, die beim Vorrücken der großen Talgletscher durch das Abdämmen von Seitentälern entstanden. Der Stauraum der Seen wurde dabei weitgehend von Bachschutt und Seeton aufgefüllt. Während des Hochglazials lag Gletschereis über den Stausedimenten, wie aus Moränen im Hangenden hervorgeht.
Mit dem Abschmelzen der Gletscher begann die Erosion der Talverfüllungen. Sie verlief zunächst sehr stürmisch. Nach dem Aufkommen eines genügenden Vegetationschutzes wurde ein labiles Gleichgewicht zwischen Abtrag und Bodenbildung erreicht, das nach den Angaben von KARL et al. (1969) seit etwa 150 Jahren offenbar von einer neuen Phase beschleunigter Erosion abgelöst wird. Zweifellos hat der wirtschaftende Mensch dieses Anschwellen des Hangabtrages verursacht. Im bayerischen Alpenraum liefern Stausedimente einen großen Teil der Wildbachgeschiebe. Eine eingehende Untersuchung der erosionsbedingenden Faktoren und der Mechanik der Massenverlagerung in einem Talverfüllungsbereich erschien uns deshalb notwendig. Dazu bot sich das Gebiet mit der größten Konzentration gefährlicher, vegetationsloser Geschiebeherde an: das Lainbachtal östlich von Benediktbeuern. Für die technische Verbauung des Baches und die vor 16 Jahren begonnenen Erlenbepflanzungen der Rutsch- und Erosionsflächen (= Blaiken) auf seinen Einhängen hat man von 1886 bis 1969 rund 4,2 Millionen DM ausgegeben, ohne damit eine völlige Beruhigung zu erzielen.
Grunwald S, Lowery B, Rooney DJ and McSweeney K (2001), "Profile cone penetrometer data used to distinguish between soil materials", Soil & Tillage Research., October, 2001. Vol. 62(1-2), pp. 27-40.
Abstract: In young glaciated landscapes the variability of soil materials imparts a major control on crop growth and yield and environmental quality associated with production agriculture. Two common soil materials found on these glaciated landscapes are glacial till and reworked loess. Soil materials can be characterized by a combination of physical and morphological soil attributes. We hypothesized that penetration resistance is the response signal to a complex of multiple soil attributes and can be used as an integrating indicator to map soil materials. Our objective was to test the ability of a profile cone penetrometer to map soil materials at lands cape-scale. The study site was located in southern Wisconsin, USA, on soils developed in reworked loess material overlying glacial till, which are classified as Typic or Mollic Hapludalfs and Typic Argiudolls. We collected a dense data set of cone index profiles from a 2.73 ha. area on a 10 m grid up to depths of 1.3 m. Additionally, we collected soil cores randomly at 21 penetration locations and analyzed these by layer for texture, bulk density, and water content. We utilized point elevation data collected with a differential global positioning system to create a digital elevation model and derive slope and compound topographic index to subdivide the study area into landform element classes. We used expert knowledge to characterize soil materials and subsequently measured soil attributes to identify soil materials. A hierarchical cluster analysis was used to group cone index profiles. Combining the sparse soil material data with the dense cone index and landform element data resulted in soil material information covering, the entire study area. The spatial distribution of soil materials was visualized using a three-dimensional soil layer model. The proposed method is associated with large uncertainties in some areas and can be recommended only for coarse mapping of contrasting soil materials such as glacial till and reworked loess at landscape-scale, when used in combination with landform. element data. (C) 2001 Elsevier Science B.V. All rights reserved.
Grunwald S, McSweeney K, Rooney DJ and Lowery B (2001), "Soil layer models created with profile cone penetrometer data", Geoderma., September, 2001. Vol. 103(1-2), pp. Int Union Soil Sci, Working Grp Pedometr.
Abstract: In creating soil layer models for our study site, we were challenged (i) to express vagueness of our soil data, while at the same time maintaining adherence to systematic classification principles, and (ii) to describe continuously the spatial distribution of soil materials and layers in three dimensions. We developed a method to create 3-dimensional (3-D) continuous soil layer models describing the distribution of soil materials, reworked loess vs. glacial till. Soil attribute data such as texture, bulk density and water content, in combination with penetration resistance obtained with a profile cone penetrometer on a 10-m grid, were used to describe soil materials and layers. We compared crisp hierarchical clustering with fuzzy k-mean classification in creating soil layer models for a 2.73-ha site in southern Wisconsin. The continuous 3-D soil layer models were developed using horizontal ordinary kriging and vertical linear interpolation. Validation proved that the crisp 3-D soil layer model predicted soil layers more accurately than the fuzzy 3-D soil layer model. We conclude that at the working scale, the crisp classification is superior to the fuzzy classification. (C) 2001 Elsevier Science B.V. All rights reserved.
Grunwald S, Rooney DJ, McSweeney K and Lowery B (2001), "Development of pedotransfer functions for a profile cone penetrometer", Geoderma., March, 2001. Vol. 100(1-2), pp. 25-47. Elsevier Science Bv.
Abstract: In this study, we illustrate how profile cone penetrometers (PCP), can be used to measure penetration resistance rapidly to define zones similar in cone index (CI), which can be related to soil physical properties. The objective of this study was (i) to develop pedopedotransfer functions, which describe the relationship between CI and soil texture, bulk density (rho (b)) and water content (theta), and (ii) to evaluate the sensitivity of parameters used in these functions. The data set represented soils formed in reworked silty loess overlying glacial till and/or lacustrine sediments. The global data set were grouped into subsets in terms of similar CIs. A horizontal hierarchical cluster analysis and a vertical point inflection method were used to derive cone index layer profiles (CILP1 to CILP5). Variability of CI within CILPs was small and variability of CI among CILPs was large. Within each group, CI was regressed with soil physical properties to develop pedopedotransfer functions. These were evaluated using the coefficient of determination (R-2). A sensitivity analysis was executed to evaluate the relative importance of different parameters in the regression models. For the total data set, R-2 ranged from 0.35 to 0.48. Pedotransfer functions for the CILPs showed largest R-2 with 0.62 for CILP1, 0.76 for CILP2, 0.70 for CILP3, 0.63 for CILP4 and 0.98 for CILP5. Depth, rho (b), clay content and a were variables with large predictive power. Textural variables had strong predictive power in the top layers, CILP1 and CILP2. In CILP4 clay contents along with rho (b) and theta were variables with large predictive power. In contrast, the predictive power of rho (b) and a was strong in layers CILP3 and CILP5, whereas soil textural characteristics showed weak predictability of CI. Pedotransfer functions using the global data set showed large sensitivities for rho (b) and theta. Similar results were obtained for all other CILPs, except CILP4 where clay content showed a large sensitivity. Our results show that pedotransfer penetrometer data can improve our understanding of the spatial distribution of CI and soil physical properties at fine scale. (C) 2001 Elsevier Science B.V. All rights reserved.
Gutknecht D (1996), "Österreichische Wasser- und Abfallwirtschaft" Vol. 48
Guzzetti F, Cardinali M, Reichenbach P, Cipolla F, Sebastiani C, Galli M and Salvati P (2004), "Landslides triggered by the 23 November 2000 rainfall event in the Imperia Province, Western Liguria, Italy", Engineering Geology., June, 2004. Vol. 73(3-4), pp. European Geophys Soc.
Abstract: From mid-October to 22 November 2000, the western Liguria Region of Italy experienced prolonged and intense rainfall, with cumulative values exceeding 1000 mm in 45 days. The severe rainfall sequence ended on November 23 with a high-intensity storm that dumped more than 180 mm of rain in 24 h. The high-intensity event caused flooding and triggered more than 1000 soils slips and debris flows and a few large, complex landslides. Slope failures caused three fatalities and severe damage to roads, private homes, and agriculture. Large (1: 13,000) and very large (1:5000) scale colour aerial photographs were taken 45 days after the event over the areas most affected by the landslides. Through the interpretation of the 334 photographs covering an area of similar to 500 km(2), we prepared a landslide inventory map that shows 1204 landslides, for a total landslide area of 1.6 km(2). We identified the rainfall conditions that triggered landslides in the Armea valley using cumulative- and continuous-rainfall data, combined with detailed information on the time of landslide occurrence. Landslide activity initiated 8 to 10 h after the beginning of the storm, and the most abundant activity occurred in response to rainfall intensities of 8 to 10 mm per hour. For the Ceriana Municipality, an area where the landslides were numerous in November 2000, we also collected information about a historical event that occurred on 8 - 11 December 19 10 and triggered abundant landslides resulting in severe economic damage. A comparison of the damage caused by the historical and the recent landslide events indicated that damage caused by the 1910 historical event was more diffused but less costly than the damage caused by the 2000 event. (C) 2004 Elsevier B.V. All rights reserved.
Guzzetti F, Carrara A, Cardinali M and Reichenbach P (1999), "Landslide hazard evaluation: a review of current techniques and their application in a multi-scale study, Central Italy", Geomorphology., December, 1999. Vol. 31(1-4), pp. 181-216. Elsevier Science Bv.
Abstract: In recent years, growing population and expansion of settlements and life-lines over hazardous areas have largely increased the impact of natural disasters both in industrialized and developing countries. Third world countries have difficulty meeting the high costs of controlling natural hazards through major engineering works and rational land-use planning. Industrialized societies are increasingly reluctant to invest money in structural measures that can reduce natural risks. Hence, the new issue is to implement warning systems and land utilization regulations aimed at minimizing the loss of lives and property without investing in long-term, costly projects of ground stabilization. Government and research institutions worldwide have long attempted to assess landslide hazard and risks and to portray its spatial distribution in maps. Several different methods for assessing landslide hazard were proposed or implemented. The reliability of these maps and the criteria behind these hazard evaluations are ill-formalized or poorly documented. Geomorphological information remains largely descriptive and subjective. It is, hence, somewhat unsuitable to engineers, policy-makers or developers when planning land resources and mitigating the effects of geological hazards. In the Umbria and Marche Regions of Central Italy, attempts at testing the proficiency and limitations of multivariate statistical techniques and of different methodologies for dividing the territory into suitable areas for landslide hazard assessment have been completed, or are in progress, at various scales. These experiments showed that, despite the operational and conceptual limitations, landslide hazard assessment may indeed constitute a suitable, cost-effective aid to land-use planning. Within this framework, engineering geomorphology may play a renewed role in assessing areas at high landslide hazard, and helping mitigate the associated risk. (C) 1999 Elsevier Science B.V. All rights reserved.
Guzzetti F, Galli M, Reichenbach P, Ardizzone F and Cardinali M (2006), "Landslide hazard assessment in the Collazzone area, Umbria, Central Italy", Natural Hazards and Earth System Sciences. Vol. 6(1), pp. 115-131.
Abstract: We present the results of the application of a recently proposed model to determine landslide hazard. The model predicts where landslides will occur, how frequently they will occur and how large they will be in a given area. For the Collazzone area, in the central Italian Apennines, we prepared a multi-temporal inventory map through the interpretation of multiple sets of aerial photographs taken between 1941 and 1997 and field surveys conducted in the period between 1998 and 2004. We then partitioned the 79 square kilometres study area into 894 slope units, and obtained the probability of spatial occurrence of landslides by discriminant analysis of thematic variables, including morphology, lithology, structure and land use. For each slope unit, we computed the expected landslide recurrence by dividing the total number of landslide events inventoried in the terrain unit by the time span of the investigated period. Assuming landslide recurrence was constant, and adopting a Poisson probability model, we determined the exceedance probability of having one or more landslides in each slope unit, for different periods. We obtained the probability of landslide size, a proxy for landslide magnitude, by analysing the frequency-area statistics of landslides, obtained from the multi-temporal inventory map. Lastly, assuming independence, we determined landslide hazard for each slope unit as the joint probability of landslide size, of landslide temporal occurrence, and of landslide spatial occurrence.
Guzzetti F, Peruccacci S, Rossi M and Stark CP (2008), "The rainfall intensity-duration control of shallow landslides and debris flows: an update", Landslides., February, 2008. Vol. 5(1), pp. 3-17.
Abstract: A global database of 2,626 rainfall events that have resulted in shallow landslides and debris flows was compiled through a thorough literature search. The rainfall and landslide information was used to update the dependency of the minimum level of rainfall duration and intensity likely to result in shallow landslides and debris flows established by Nel Caine in 1980. The rainfall intensity-duration (ID) values were plotted in logarithmic coordinates, and it was established that with increased rainfall duration, the minimum average intensity likely to trigger shallow slope failures decreases linearly, in the range of durations from 10 min to 35 days. The minimum ID for the possible initiation of shallow landslides and debris flows was determined. The threshold curve was obtained from the rainfall data using an objective statistical technique. To cope with differences in the intensity and duration of rainfall likely to result in shallow slope failures in different climatic regions, the rainfall information was normalized to the mean annual precipitation and the rainy-day normal. Climate information was obtained from the global climate dataset compiled by the Climate Research Unit of the East Anglia University. The obtained global ID thresholds are significantly lower than the threshold proposed by Caine (Geogr Ann A 62:23-27, 1980), and lower than other global thresholds proposed in the literature. The new global ID thresholds can be used in a worldwide operational landslide warning system based on global precipitation measurements where local and regional thresholds are not available..
Guzzetti F, Peruccacci S, Rossi M and Stark CP (2007), "Rainfall thresholds for the initiation of landslides in central and southern Europe", Meteorology and Atmospheric Physics., December, 2007. Vol. 98(3-4), pp. 239-267.
Abstract: We review rainfall thresholds for the initiation of landslides world wide and propose new empirical rainfall thresholds for the Central European Adriatic Danubian South-Eastern Space (CADSES) area, located in central and southern Europe. One-hundred-twenty-four empirical thresholds linking measurements of the event and the antecedent rainfall conditions to the occurrence of landslides are considered. We then describe a database of 853 rainfall events that resulted or did not result in landslides in the CADSES area. Rainfall and landslide information in the database was obtained from the literature; climate information was obtained from the global climate dataset compiled by the Climate Research Unit of the East Anglia University. We plot the intensity-duration values in logarithmic coordinates, and we establish that with increased rainfall duration the minimum intensity likely to trigger slope failures decreases linearly, in the range of durations from 20 minutes to similar to 12 days. Based on this observation, we determine minimum intensity-duration (ID) and normalized-ID thresholds for the initiation of landslides in the CADSES area. Normalization is performed using two climatic indexes, the mean annual precipitation (MAP) and the rainy-day-normal (RDN). Threshold curves are inferred from the available data using a Bayesian statistical technique. Analysing the obtained thresholds we establish that lower average rainfall intensity is required to initiate landslides in an area with a mountain climate, than in an area characterized by a Mediterranean climate. We further suggest that for rainfall periods exceeding similar to 12 days landslides are triggered by factors not considered by the ID model. The obtained thresholds can be used in operation landslide warning systems, where more accurate local or regional thresholds are not available.
Guzzetti F, Reichenbach P, Ardizzone F, Cardinali M and Galli M (2006), "Estimating the quality of landslide susceptibility models", Geomorphology., November, 2006. Vol. 81(1-2), pp. 166-184.
Abstract: We present a landslide susceptibility model for the Collazzone area, central Italy, and we propose a framework for evaluating the model reliability and prediction skill. The landslide susceptibility model was obtained through discriminant analysis of 46 thematic environmental variables and using the presence of shallow landslides obtained from a multi-temporal inventory map as the dependent variable for statistical analysis. By comparing the number of correctly and incorrectly classified mapping units, it is established that the model classifies 77.0% of 894 mapping units correctly. Model fitting performance is investigated by comparing the proportion of the study area in each probability class with the corresponding proportion of landslide area. We then prepare an ensemble of 350 landslide susceptibility models using the same landslide and thematic information but different numbers of mapping units. This ensemble is exploited to investigate the model reliability, including the role of the thematic variables used to construct the model, and the model sensitivity to changes in the input data. By studying the variation of the model's susceptibility estimate, the error associated with the susceptibility assessment for each mapping unit is determined. This result is shown on a map that complements the landslide susceptibility map. Prediction skill of the susceptibility model is then estimated by comparing the forecast with two recent event inventory maps. The susceptibility model is found capable of predicting the newly triggered landslides. A general framework for testing a susceptibility model is proposed, including a scheme for ranking the quality of the susceptibility assessment. (c) 2006 Elsevier B.V. All rights reserved.
Guzzetti F, Reichenbach P, Cardinali M, Galli M and Ardizzone F (2005), "Probabilistic landslide hazard assessment at the basin scale", Geomorphology., December, 2005. Vol. 72(1-4), pp. 272-299.
Abstract: We propose a probabilistic model to determine landslide hazard at the basin scale. The model predicts where landslides will occur, how frequently they will occur, and how large they will be. We test the model in the Staffora River basin, in the northern Apennines, Italy. For the study area, we prepare a multi-temporal inventory map through the interpretation of multiple sets of aerial photographs taken between 1955 and 1999. We partition the basin into 2243 geo-morpho-hydrological units, and obtain the probability of spatial occurrence of landslides by discriminant analysis of thematic variables, including morphological, lithological, structural and land use. For each mapping unit, we obtain the landslide recurrence by dividing the total number of landslide events inventoried in the unit by the time span of the investigated period. Assuming that landslide recurrence will remain the same in the future, and adopting a Poisson probability model, we determine the exceedance probability of having one or more landslides in each mapping unit, for different periods. We obtain the probability of landslide size by analysing the frequency-area statistics of landslides, obtained from the multi-temporal inventory map. Assuming independence, we obtain a quantitative estimate of landslide hazard for each mapping unit as the joint probability of landslide size, of landslide temporal occurrence and of landslide spatial occurrence. (c) 2005 Elsevier B.V. All rights reserved.
Guzzetti F, Stark CP and Salvati P (2005), "Evaluation of flood and landslide risk to the population of Italy", Environmental Management., July, 2005. Vol. 36(1), pp. 15-36.
Abstract: We have compiled a database of floods and landslides that occurred in Italy between AD 1279 and 2002 and caused deaths, missing persons, injuries, and homelessness. Analysis of the database indicates that more than 50,593 people died, went missing, or were injured in 2580 flood and landslide events. Harmful events were inventoried in 26.3% of the 8103 Italian municipalities. Fatal events were most frequent in the Alpine regions of northern Italy and were caused by both floods and landslides. In southern Italy, landslides were the principal agents of fatalities and were most numerous in the Campania region, Casualties were most frequent in the autumn. Fast-moving landslides, including rock falls, rockslides, rock avalanches, and debris flows, caused the largest number of deaths. In order to assess the overall risk posed by these processes, we merged the historical catalogs and identified 2682 "hydrogeomorphological" events that triggered single or multiple landslides and floods, We estimated individual risk through the calculation of mortality rates for both floods and landslides and compared these rates to the death rates for other natural, medical, and human-induced hazards in Italy. We used the frequency distribution of events with fatalities to ascertain the magnitude and frequency of the societal risks posed by floods and landslides. We quantified these risks in a Bayesian model that describes the probabilities of fatal flood and landslide events in Italy.
Guzzetti F and Tonelli G (2004), "Information system on hydrological and geomorphological catastrophes in Italy (SICI): a tool for managing landslide and flood hazards", Natural Hazards and Earth System Sciences. Vol. 4(2), pp. 213-232.
Abstract: Since 1990, we have maintained a database of historical information on landslides and floods in Italy, known as the National Research Council's AVI (Damaged Urban Areas) archive. The database was originally designed to respond to a request of the Minister of Civil Protection, and was aimed at helping the regional assessment of landslide and flood risk in Italy. The database was compiled in 1991 1992 to cover the period 1917 to 1990, and then updated to cover systematically the period 1917 to 2000, and nonsystematically the periods 1900 to 1916 and 2001 to 2002. The database currently contains information on more than 32000 landslide events occurred at more than 21000 sites, and on more than 29 000 flood events occurred at more than 14 000 sites. Independently from the AVI archive, we have obtained other databases containing, information on damage caused by mass movements and inundations, daily discharge measurements and solid-transport measurements at selected gauging stations, bibliographical and reference information on landslides and inundations, and a catalogue of National legislation on hydrological and geological hazards and risk in Italy. The databases are part of an information system known as SICI (an Italian acronym for Sistema Informativo sulle Catastrofi Idrogeologiche, Information System on Hydrological and Geomorphological Catastrophes), which is currently the largest sin-le repository of historical information on landslides and floods in Italy, After an outline of the history and evolution of the AVI Project archive, we present and discuss: (a) the structure of the SICI information system, including the hardware and software solutions adopted to maintain, manage, update, use and disseminate the information stored in the various databases, (b) the type and amount of information stored in each database, including, an estimate of their completeness, and (c) examples of recent applications of the information system, including a web-based GIS system to show the location of sites historically affected by landslides and floods, and an estimate of geo-hydrological (i.e. landslide and flood) risk in Italy based on the available historical information.
Haala N, Cramer M, Weimer F and Trittler M (2011), "Performance test on UAV-based photogrammetric data collection", International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. Vol. XXXVIII-1/C22. UAV-g 2011, Conference on Unmanned Aerial Vehicle in Geomatics, Zurich, Switzerland, pp. 1-6.
Abstract: UAVs are becoming standard platforms for applications aiming at photogrammetric data capture. Since these systems can be completely built-up at very reasonable prices, their use can be very cost effective. This is especially true while aiming at large scale aerial mapping of areas at limited extent. Within the paper the capability of UAV-based data collection will be evaluated. These investigations will be based on flights performed at a photogrammetric test site which was already flown during extensive tests of digital photogrammetric camera systems. Thus, a comparison to conventional aerial survey with state-of-the-art digital airborne camera systems is feasible. Due to this reason the efficiency and quality of generating standard mapping products like DSM and ortho images from UAV flights in photogrammetric block configuration will be discussed.
Hadji R, Boumazbeur A, Limani Y, Baghem M, Chouabi A and Demdoum A (2013), "Geologic, topographic and climatic controls in landslide hazard assessment using GIS modeling: A case study of Souk Ahras region, NE Algeria", Quaternary International., July, 2013. Vol. 302, pp. 224-237. Pergamon-elsevier Science Ltd.
Abstract: Landslides are the most common hazard in mountainous regions of northeast Algeria. In this study, landslide hazard zonation of Souk Ahras province was carried out using a Raster-based GIS and statistical processing. Landslide locations were defined from interpretation of aerial photographs and field surveys. Rotational, planar and complex landslides were identified. To reveal the controlling factors of landslides, a temporal distribution of 603 recognized landslides (1981-2011) is compared with the monthly precipitation variation, indicating a strong correlation between precipitation and landslide occurrence. The correlation between landslide and lithology, slope angle, and elevation shows the same results. Tabular data, maps and satellite images were collected, processed, and constructed into a spatial database in a GIS platform. The factors that influence landslide occurrence, such as slope angle, slope exposition and elevation were derived from the DEM; Lithology, soil deposits and faults were digitalized from the geologic maps; roads, streams and timber were extracted from Landsat image; precipitation was krigged from pluviometric measurement dataset Different classes of thematic layers were assigned. A corresponding rating value as attribute information and an attribute map was generated for each data layer in the GIS. Landslide hazard areas were assessed and mapped using the landslide occurrence and permanent factor maps, by applying a probabilistic method with a logistic regression approach. The results of the analysis were verified using landslides location map, compared with the probability model. The resulting map can be used to mitigate this hazard, and to plan land use and urbanization. (c) 2012 Elsevier Ltd and INQUA. All rights reserved.
Hagen K (2008), "Rutschungen, eine verkannte Gefahr?", BFW-Praxisinformation. Vol. 15, pp. 13-15.
Abstract: In den letzten Jahren haben Extremniederschläge zahlreiche Rutschungen ausgelöst. Siedlungen und Infrastruktur wurden zum Teil massiv geschädigt und Todesopfer waren zu beklagen. Wie kann man rutschungsgefährdete Bereiche erkennen und welche Maßnahmen sind notwendig, um Schäden zu minimieren?
Haiden T, Kann A, Wittmann C, Pistotnik G, Bica B and Gruber C (2011), "The Integrated Nowcasting through Comprehensive Analysis (INCA) System and Its Validation over the Eastern Alpine Region", Weather and Forecasting., April, 2011. Vol. 26(2), pp. 166-183. Amer Meteorological Soc.
Abstract: This paper presents the Integrated Nowcasting through Comprehensive Analysis (INCA) system, which has been developed for use in mountainous terrain. Analysis and nowcasting fields include temperature, humidity, wind, precipitation amount, precipitation type, cloudiness, and global radiation. The analysis part of the system combines surface station data with remote sensing data in such a way that the observations at the station locations are reproduced, whereas the remote sensing data provide the spatial structure for the interpolation. The nowcasting part employs classical correlation-based motion vectors derived from previous consecutive analyses. In the case of precipitation the nowcast includes an intensity-dependent elevation effect. After 2-6 h of forecast time the nowcast is merged into an NWP forecast provided by a limited-area model, using a predefined temporal weighting function. Cross validation of the analysis and verification of the nowcast are performed. Analysis quality is high for temperature, but comparatively low for wind and precipitation, because of the limited representativeness of station data in mountainous terrain, which can be only partially compensated by the analysis algorithm. Significant added value of the system compared to the NWP forecast is found in the first few hours of the nowcast. At longer lead times the effects of the latest observations becomes small, but in the case of temperature the downscaling of the NWP forecast within the INCA system continues to provide some improvement compared to the direct NWP output.
Hamberger M and Moser M (2008), "Der Einsatz verschiedener Klassifikatoren zur Erkennung flachschaliger Rutschungen - Modellgebiet Sachseln/Schweiz", In Proc. of the XI International Congress Interpraevent 2008, Dornbirn. Dornbirn Vol. 2, pp. 159-170.
Abstract: Am 15. August 1997 verursachten Starkniederschläge mit einer Intensität von 150 mm in zwei Stunden mehr als 700 kleinflächige und flachschalige Rutschungen, die zu großen Vermurungen in den Talbereichen in der Umgebung von Sachseln und des Melchtales in der Schweiz führten. In den Folgejahren wurden im Rahmen verschiedener Projekte umfangreiche Aufnahmen durchgeführt, um den Einfluss verschiedener Parameter auf die Rutschaktivität eines Hanges zu ermitteln. Die Ergebnisse dieser ersten Evaluierung zeigten, dass die Rutschungen nicht durch einen Parameter - morphologischer, geotechnischer, geologischer, hydrologischer oder vegetationskundlicher Art -, sondern eine Kombination vieler Faktoren ausgelöst wurden. Mit drei unterschiedlichen Klassifikationsverfahren, der linearen Diskriminanzanalyse, den Support Vector Machines und den Klassifikationsbäumen, wurde versucht, Parameterkonstellationen zu finden, die effizient zwischen Rutschungsbereichen und Nichtrutschungsbereichen unterscheiden. Die Ergebnisse der durchgeführten Klassifikationen belegen, dass es zum einen möglich ist, einen Großteil (81%) der Rutschungen mit verschiedenen Modellen zu erkennen, zum anderen aber auch die Möglichkeit besteht, nicht nur ca. 74 % der Rutschungen sondern ebensoviel Nichtrutschungen richtig zu klassifizieren.
Hamberger M and Moser M (2008), "Implementation of different classification methods for detecting soil slips", In Proc. of the XI International Congress Interpraevent 2008, Dornbirn. Extented Abstract. Dornbirn Vol. 2, pp. 140-141.
Abstract: On August 15th, 1997 a thunderstorm in Sachseln/Switzerland, which had a total rainfall of 150 mm over a 2 hour period, was recorded and resulted in more than 700 soil slips (Fig. 1). These soil slips were evaluated and analysed in the following years by the Swiss Federal Institute for Forest, Snow and Landscape Research of Birmensdorf/Switzerland as well as the Department of Geology at the University of Erlangen/Germany.
Hansen D (1996), "The angle of reach as a mobility index for small and large landslides: Discussion", Canadian Geotechnical Journal., December, 1996. Vol. 33(6), pp. 1027-1029.
Harden CP and Scruggs PD (2003), "Infiltration on mountain slopes: a comparison of three environments", Geomorphology. Vol. 55(1–4), pp. 5-24.
Abstract: Water is well established as a major driver of the geomorphic change that eventually reduces mountains to lower relief landscapes. Nonetheless, within the altitudinal limits of continuous vegetation in humid climates, water is also an essential factor in slope stability. In this paper, we present results from field experiments to determine infiltration rates at forested sites in the Andes Mountains (Ecuador), the southern Appalachian Mountains (USA), and the Luquillo Mountains (Puerto Rico). Using a portable rainfall simulator-infiltrometer (all three areas), and a single ring infiltrometer (Andes), we determined infiltration rates, even on steep slopes. Based on these results, we examine the spatial variability of infiltration, the relationship of rainfall runoff and infiltration to landscape position, the influence of vegetation on infiltration rates on slopes, and the implications of this research for better understanding erosional processes and landscape change.
Infiltration rates ranged from 6 to 206 mm/h on lower slopes of the Andes, 16 to 117 mm/h in the southern Appalachians, and 0 to 106 mm/h in the Luquillo Mountains. These rates exceed those of most natural rain events, confirming that surface runoff is rare in montane forests with deep soil/regolith mantles. On well-drained forested slopes and ridges, apparent steady-state infiltration may be controlled by the near-surface downslope movement of infiltrated water rather than by characteristics of the full vertical soil profile. With only two exceptions, the local variability of infiltration rates at the scale of 10° m overpowered other expected spatial relationships between infiltration, vegetation type, slope position, and soil factors. One exception was the significant difference between infiltration rates on alluvial versus upland soils in the Andean study area. The other exception was the significant difference between infiltration rates in topographic coves compared to other slope positions in the tabonuco forest of one watershed in the Luquillo Mountains. Our research provides additional evidence of the ability of forests and forest soils to preserve geomorphic features from denudation by surface erosion, documents the importance of subsurface flow in mountain forests, and supports the need for caution in extrapolating infiltration rates.
Hartwagner W (1998), "Blaikensanierung am Beispiel Bürgerbach", Wildbach- und Lawinenverbau. Vol. 62(136), pp. 113-125.
Haylock M, Hofstra N, Tank AK, Klok E, Jones P and New M (2008), "A European daily high-resolution gridded data set of surface temperature and precipitation for 1950-2006", Journal of Geophysical Research. Vol. 113(D20), pp. D20119. American Geophysical Union.
Abstract: We present a European land-only daily high-resolution gridded data set for precipitation and minimum, maximum, and mean surface temperature for the period 1950–2006. This data set improves on previous products in its spatial resolution and extent, time period, number of contributing stations, and attention to finding the most appropriate method for spatial interpolation of daily climate observations. The gridded data are delivered on four spatial resolutions to match the grids used in previous products as well as many of the rotated pole Regional Climate Models (RCMs) currently in use. Each data set has been designed to provide the best estimate of grid box averages rather than point values to enable direct comparison with RCMs. We employ a three-step process of interpolation, by first interpolating the monthly precipitation totals and monthly mean temperature using three-dimensional thin-plate splines, then interpolating the daily anomalies using indicator and universal kriging for precipitation and kriging with an external drift for temperature, then combining the monthly and daily estimates. Interpolation uncertainty is quantified by the provision of daily standard errors for every grid square. The daily uncertainty averaged across the entire region is shown to be largely dependent on the season and number of contributing observations. We examine the effect that interpolation has on the magnitude of the extremes in the observations by calculating areal reduction factors for daily maximum temperature and precipitation events with return periods up to 10 years.
He S, Pan P, Dai L, Wang H and Liu J (2012), "Application of kernel-based Fisher discriminant analysis to map landslide susceptibility in the Qinggan River delta, Three Gorges, China", Geomorphology., October, 2012. Vol. 171, pp. 30-41.
Abstract: Kernel machines are widely applied in classification because of many typical advantages, such as a good capacity to deal with high-dimensional data, good generation performance, few parameters to adjust, explainable results, etc. The kernel-based Fisher discriminant analysis (KFDA) is a typical kernel-based method based on the statistical discriminant analysis and it includes both the training and testing process. The model is trained by a dataset of environmental factors that cause landslide occurrence and target output values. Furthermore, the trained model is tested by a separate set of testing samples. This approach utilizes a kernel function to map data from the original feature space to a high-dimensional space, through which a nonlinear problem is converted into a linear one. A typical landslide study area, namely Qinggan River delta, situated in Three Gorges, China, is selected for this study and the following environmental factors are determined as independent variables of the model-lithology, elevation, normalized difference vegetation index (NDVI), slope, aspect, distance to rivers, plan curvature, and profile curvature. Judging from the accuracies of the training and testing samples, the sigmoid kernel performed better than the radial basis function kernel and the polynomial kernel. Using different ratios of landslide to non-landslide samples, the performance of KFDA is compared with the linear Fisher discriminant analysis (LFDA) and the logistic regression using a ROC/AUC validation. The results reveal that the average performance of KFDA for all ratios of samples is the most optimal with the mean AUC value as high as 0.911, while the mean AUC values of the logistic regression and LFDA are 0.867 and 0.089 respectively. Although the logistic regression performed slightly better than KFDA when the ratio of landslide to non-landslide samples was 2:1 and 3:1, its AUC values for other ratios of samples are much lower than the AUC values of KFDA. KFDA is more robust and less sensitive to different ratios of samples. The susceptibility map produced by KFDA shows that the regions around rivers are highly at risk to the occurrence of landslides in the study area. (C) 2012 Elsevier B.V. All rights reserved.
Heath GH and Luckwill LC (1938), "The rooting systems of heath plants", Journal of Ecology. Vol. 26, pp. 331-352.
Abstract: Fritsch & Salisbury (1915) in their account of the vegetation of Hindhead Common give notes on the working and maximum depths of the rooting systems of the dominant plants. Other than these preliminary observations there appears to be no account of the underground organs of heath plants in the published literature, and the present investigation was undertaken in order to gain knowledge of this little-known though important aspect of the heath flora.
The observations were made on a stretch of heathland known as Blackdown, situated on the Mendip Hills in Somerset. A full account of the vegetation of Blackdown and of the ecological factors determining it are being published elsewhere, but a brief summary of the general ecology is given below. Special attention has been directed to those features which might be expected to influence, either directly or indirectly, the form of the rooting system.
Heckmann T and Becht M (2009), "Investigating the Transferability of Statistical Disposition Models For Slope-type Debris Flows", Erdkunde., January, 2009. Vol. 63(1), pp. 19-33. Boss Druck Medien Gmbh.
Abstract: Statistical disposition models are used both in geomorphology and in natural hazards research to spatially predict the occurrence of mass movements, other geomorphic processes or landforms. This is achieved by establishing some statistical relationship between an inventory of mapped occurrences and relevant geofactor maps. Statistical approaches rely, among others, on the assumption that future events will take place under the same conditions as they did in the past. In the present paper, the Certainty Factor (one of the favourability functions) is used to quantify the association of debris flow initiation sites with the geofactors landcover, slope and CIT index in three alpine study areas. The transferability of the models, i.e. their applicability to other study areas, is investigated using a comparison of model results (CF parameters) from different study areas and an extensive cross-validation. It is shown that, in similar study areas, the model parameters are generally very similar, indicating that the geofactors represent well enough the relevent conditions and processes that lead to debris flow initiation. The cross-validation is generally successful, independent of the similarity of the area for which the model has been established and the target area. Therefore, it can be concluded that statistical disposition models such as the CF model are, in principle, transferable between study areas. Nevertheless, some critical issues such as data quality have to be kept in mind when trying to apply a model to another study area,
Heckmann T and Becht M (2006), "Statistical disposition modelling of mass movements", SAGA-analysis and modelling applications. Göttinger Geographische Abhandlun-Göttinger Geographische Abhandlungen. Vol. 115, pp. 61-73.
Abstract: Disposition models are used to delineate potential starting zones for various geomorphic processes that may also act as natural hazards (snow avalanches, debris flows, earth flows, landslides). Various approaches of statistical disposition models have in common that they require mapped starting zones and a set of categorised geofactors considered relevant for process initiation. We have implemented the certainty factor approach, representing one of the favourability functions that had previously been used for spatial models of landslide susceptibility and mineral resources. The SAGA modules presented here are used to develop a spatial disposition model, to apply existing models to different areas and to validate model results using subsets of input data. After a description of the calculation of certainty factors, a case study is presented with respect to data requirements, model results and validation, followed by a detailed discussion of model assumptions, problematic issues and future work.
Hegg C, Badoux A, Lüscher P and Witzig J (2004), "Zur Schutzwirkung des Waldes gegen Hochwasser", In Schutzwald und Naturgefahren. Forum für Wissen 2004. , pp. 15-20. WSL.
Abstract: Mitte des 19. Jahrhunderts wurde die Schweiz von mehreren schweren Hochwasserereignissen heimgesucht. Sowohl die Fachwelt als auch die Öffentlichkeit sahen dabei einen ursächlichen Zusammenhang zwischen dem schlechten Zustand des Gebirgswaldes und dem Ausmass der Hochwasser. Diese Feststellung war ein wichtiger Anstoss für das Forstgesetz von 1876. In seiner wegweisenden Publikation von 1919 belegte Engler diese Feststellung teilweise indem er aufzeigte, dass Wälder vor allem bei kurzen und intensiven Starkniederschlägen eine massgebende Dämpfung einer Hochwasserwelle bewirken. Engler zeigte allerdings auch, dass diese dämpfende Wirkung mit zunehmendem Niederschlagsvolumen mehr und mehr abnimmt, weil dann der Bodenspeicher sowohl in Gebieten mit als auch ohne Wald gefüllt ist. In den letzten Jahren haben verschiedene Untersuchungen gezeigt, dass nicht jeder Wald in der Lage ist, Hochwasserspitzen massgeblich zu dämpfen. Nachfolgend werden diese Ergebnisse kurz erläutert und auf ein mögliches Vorgehen zur differenzierten Beurteilung der Schutzwirkung eines Waldes gegen Hochwasser hingewiesen.
Hegg C, Bezzola G and Koschni A (2008), "Ereignisanalyse Hochwasser 2005 in der Schweiz", In Proc. of the XI International Congress Interpraevent 2008, Dornbirn. Dornbirn Vol. 2, pp. 27-38.
Abstract: Das Hochwasser vom August 2005 forderte in der Schweiz 6 Todesopfer und verursachte Sachschäden in der Höhe von insgesamt 3 Mrd. Franken. Hinsichtlich der Schäden ist es somit innerhalb der letzten drei Jahrzehnte ohne Parallele. Grossflächige und lang anhaltende Niederschläge führten zu aussergewöhnlichen Abflüssen und Seeständen. Überflutung, Erosion, Übersarung, Rutschungen und Übermurung waren die massgebenden Schadensprozesse. In seiner Gesamtheit und über eine längere Zeitperiode betrachtet, ist das Ereignis aber nicht als aussergewöhnlich, sondern höchstens noch als selten zu bezeichnen. Mit dem wiederholten Auftreten ähnlicher Hochwasser muss auch in Zukunft gerechnet werden.
Hegg C, Gerber D and Röthlisberger G (2000), "Unwetterschaden-Datenbank der Schweiz", In Proc. of the IX International Congress Interpraevent 2000, Villach. Vol. 1, pp. 37-48.
Abstract: Seit 1972 werden an der WSL anhand von Zeitungsmeldungen systematisch Angaben zu Unwetterschäden durch Hochwasser und Rutschungen gesammelt und aufbereitet. Die Schadensmeldungen werden für jede Wetterlage zusammengefasst und in bezug auf die Schadenstärke, die Schadenursache und die Art der Schäden analysiert. Um diese Informationen besser zugänglich zu machen. wurden die Daten in eine digitale Datenbank: übergeftlhrt. Dabei wurden die pro Wetterlage zusammengefassten Informationen auf einzelne Schadenorte aufgeteilt und damit eine wesentlich feinere räumliche Auflösung erzielt. Auf diese Weise entstand ein umfangreicher Datensatz, der die seit 1972 aufgelaufenen 5,3 Mia. CHF Unwenerschäden (nicht teuerungsbereinigt) eindrücklich belegt. Durchschninlich haben Unwetter in der Schweiz seit 1972 jedes Jahr finanzielle Schäden von ca. 200 Mio. CHF verursacht und im Mittel auch 2 Todesopfer gefordert. Etwa 40 % der finanziellen Schäden sind von 4 Grossereignissen verursacht worden, die durch von SUden Uber die Alpen greifenden Starkniederschlagsfeldern ausgelöst wurden. Einen traurigen Rekord stellte das Jahr 1999 mit mind. 25 Todesopfern auf. Der grösste Teil davon (21 Personen) geht auf ein tragisches Canyoning-Unglück im Berner Oberland zurück.
Hegg C and Kienholz H (1992), "Hangprozesse: Grenzen und Möglichkeiten der Simulation", In Proc. of the VII International Congress Interpraevent 1992, Bern. Bern Vol. 4, pp. 175-186.
Abstract: Im Zusammenhang mit Untersuchungen zur Feststofflieferung in Wildbächen wurde ein Geographisches Informationssystem als Hilfsmittel zur Simulation von Hangprozessen verwendel. Es zeigte sich, dass Verfahren, die eine Polygonkaskadierung als Trajektorienmodell verwenden, unter bestimmten Umständen unrealistische Wege für Hangprozesse berechnen. Aus diesem Grunde wurde ein neues Trajektorienmodell entwickelt und getestet, bei dem die Wege durch Vektorenzüge gebildet werden. Dieses Verfahren hat bis heute durchwegs plausible Resultate geliefen.
Hegg C and Rhyner J (2007), "Warnung bei aussergewöhnlichen Naturereignissen", In Forum für Wissen. Eidgenössische Forschungsanstalt WSL.
Heimsath A, Dietrich W, Nishiizumi K and Finkel R (1999), "Cosmogenic nuclides, topography, and the spatial variation of soil depth", Geomorphology. Vol. 27, pp. 151-172.
Abstract: If the rate of bedrock conversion to a mobile layer of soil depends on the local thickness of soil, then hillslopes on uniform bedrock in a landscape approaching dynamic equilibrium should be mantled by a uniform thickness of soil. Conversely, if the depth of soil varies across an actively eroding landscape, then rates of soil production will also vary and, consequently the landscape will not be in morphologic equilibrium. The slow evolution of hillslopes relative to the tempo of climatic variations and tectonic adjustments would suggest that local morphologic disequilibrium may be expected in many landscapes. Here, we explore this issue of equilibrium landscapes through a previously developed model that predicts the spatial variation in thickness of soil as a consequence of the local balance between soil production and erosion. First, we confirm the assumption in the model that soil production varies inversely with the thickness of soil using two independent methods. One method uses the theoretical prediction that at local steady state (soil production equals removal), the depth of soil should vary inversely with hillslope curvature. The second method relies on direct measurements of in situ produced concentrations of cosmogenic 10Be and 26Al in bedrock at the base of the soil column. For our study site in Northern California, the two methods agree and yield the expression that the rate of soil production declines exponentially with the thickness of soil from 0.077 mmryear with no soil mantle to 0.0077 mmryear under 1 m of soil. We then use this function of soil production in a coupled production and diffusive model of sediment transport to explore the controls on the spatial variation of the depth of soil on four separate spur ridges (noses) where we measured the data for the function of soil production. Model predictions are sensitive to boundary conditions, grid scale, and run time. Nonetheless, we found good agreement between predicted and observed depths of soil as long as we used the observed function of soil production. The four noses each have spatially varying curvature and, consequently, have varying depths of soil, implying morphologic disequilibrium. We suggest that our study site has been subjected to a wave of incision and varying intensities of erosion because of tectonic and climatic oscillations that have a frequency shorter than the morphologic response time of the landscape. q1999 Elsevier Science B.V. All rights reserved.
Held A (1951), "Beitrag zu einer Definition für Starkregen im Ostalpengebiet", Archiv für Meteorologie, Geophysik und Bioklimatologie, Serie B. Vol. 2(5), pp. 448-461. Springer-Verlag.
Abstract: Schon vor etlichen Jahren hat man die Unzulänglichkeiten der früheren Starkregendefinitionen klar formuliert (vor allem in England) und nunmehr durch die Betonung der Häufigkeitn eine verbesserte Definition gefordert. Mit Hilfe von deutschen Auswerteverfahren für Ombrographenregistrierungen wird in vorliegender Arbeit der Versuch unternommen, auf dieser neuen Basis eine für Österreich gültige, aber allgemein vergleichbare Definition der Starkregen zu finden, und es ergibt sich, daß als Starkregen in Österreich ein Regenfall zu bezeichnen ist, der die Intensität eines „Idealregens” erreicht oder überschreitet, der alle Jahre höchstens einmal in dieser Stärke an jeder Station des betreffenden Gebietes (aber natürlich nicht unbedingt überall gleichzeitig) vorkommen würde (n=1). AlsPlatzregen ist ein Regenfall anzusehen, der die Intensität eines höchstens alle zwei Jahre (n=1/2), und alsstarker Platzregen ein solcher, der die Intensität eines höchstens alle acht Jahre (n=1/8) vorkommenden Regens erreicht bzw. überschreitet. Auf eine formelmäßige Erfassung dieser Grenzkurve wird hier verzichtet, weil solcherart kaum ein einfacher und praktisch verwendbarer Ausdruck gegeben werden könnte; vielmehr werden die zu den festgelegtenn gehörigen Intensitätswerte für vier regengeographisch verschiedene Hauptgebiete Österreichs in einer Tabelle gegeben.
Hengl T (2007), "A practical guide to geostatistical mapping of environmental variables" Vol. 140(4)
Hengl T, Heuvelink GB and Stein A (2004), "A generic framework for spatial prediction of soil variables based on regression-kriging", Geoderma. Vol. 120, pp. 75-93.
Abstract: A methodological framework for spatial prediction based on regression-kriging is described and compared with ordinary kriging and plain regression. The data are first transformed using logit transformation for target variables and factor analysis for continuous predictors (auxiliary maps). The target variables are then fitted using step-wise regression and residuals interpolated using kriging. A generic visualisation method is used to simultaneously display predictions and associated uncertainty. The framework was tested using 135 profile observations from the national survey in Croatia, divided into interpolation (100) and validation sets (35). Three target variables: organic matter, pH in topsoil and topsoil thickness were predicted from six relief parameters and nine soil mapping units. Prediction efficiency was evaluated using the mean error and root mean square error (RMSE) of prediction at validation points. The results show that the proposed framework improves efficiency of predictions. Moreover, it ensured normality of residuals and enforced prediction values to be within the physical range of a variable. For organic matter, it achieved lower relative RMSE than ordinary kriging (53.3% versus 66.5%). For topsoil thickness, it achieved a lower relative RMSE (66.5% versus 83.3%) and a lower bias than ordinary kriging (0.15 versus 0.69 cm). The prediction of pH in topsoil was difficult with all three methods. This framework can adopt both continuous and categorical soil variables in a semi-automated or automated manner. It opens a possibility to develop a bundle algorithm that can be implemented in a GIS to interpolate soil profile data from existing datasets.
Hennrich K and Crozier MJ (2004), "A hillslope hydrology approach for catchment-scale slope stability analysis", Earth Surface Processes and Landforms., May, 2004. Vol. 29(5), pp. 599-610.
Abstract: Regional analysis of slope stability is often constrained by availability of data. Model requirements for input data cannot be met at the desired spatial resolution because data are either site-specific or non-existent. Faced with these difficulties it has often been the practice to assume that certain parameters are uniform throughout the area of interest. An alternative approach proposed here allows a more detailed discrimination of slope stability conditions. Based on the principles of hillslope hydrology, hydrologic information can be generated at sufficient resolution to allow higher resolution slope stability analysis. Measurements from an instrumented network in a small area have been used to establish index-based models for topographic and climate-related controls of piezometric response. The ability to relate groundwater levels to rainfall and topographic parameters provides a means of up-scaling to larger catchments and ultimately the opportunity to generate a catchment-wide prediction of the distribution, magnitude and frequency of rainstorm-generated groundwater levels. The example provided in this study uses the topography index of TOPMODEL in GIS to predict the spatial patterns of groundwater elevation for seasonal soil moisture conditions and given rainfall inputs. This allows modelling of catchment-wide response of soil water to rainstorms with different return periods (representing different magnitudes), and is an essential prerequisite for a probabilistic regional slope stability analysis. Copyright (C) 2004 John Wiley Sons, Ltd.
Hensold S, Wichmann V and Becht M (2005), "Hydrologische Differenzierung von Standorten in einem alpinen Einzugsgebiet in Abhängigkeit von physisch-geographischen Parametern", Hydrologie und Wasserbewirtschaftung. Vol. 49(2), pp. 68-76.
Abstract: Oie Untersuchung wurde im nordwesllich von Garmisch-Partenkirchen gelegenen Einzugsgebiet des Lahnenwiesgrabens (Ammergebirge) durchgeführt. Auf 34 Standortflächen wurden die feldgesättigten hydraulischen Leitfähigkeiten mit einem Guelph-Permeameter ermittelt. Anhand digital vorliegender Karten der Vegetation, der Böden und der Geologie wurden die Messergebnisse mit einem Geographischen Inlormationssystem (GIS) klassifiziert und anschließend im Einzugsgebiet regionalisiert. Die resultierende Karte liefert flächendeckende Informationen über das hydrologische Verhalten einzelner Standortkombinationen. So sind beispielsweise Rückschlüsse auf die Bereitschaft zur Bildung von Oberflächenabflüssen möglich. Eine Einschätzung der hydrologischen Standorteigenschaften ist aueh für die Modellierung von hydrologischen und geomorphoJogischen Prozessen von Bedeutung.
This study was conducted in the catchment area of the Lahnenwiesgraben in the Ammergebirge Mountains north-wesl of Garmisch-Partenkirchen. At 34 sites the field-saturated hydraulic conductivity was measured with a Guelph-Permeameter. The measurements were classilied with a geographie information system (GIS) by means 01 available digital maps 01 vegetation, soils, and geology and were finally regionalized in the catchment. The resulting map gives areal information on the hydrological behaviour of certain site eombinations, allowing e.g. to draw conclusions on Ihe disposition for surfaee runoff. The assessment of hydrological site conditions is also relevant for the modelling of hydrologie and geomorphologic proeesses.
Herrick JE and Jones TL (2002), "A dynamic cone penetrometer for measuring soil penetration resistance", Soil Science Society of America Journal., July, 2002. Vol. 66(4), pp. 1320-1324. Soil Sci Soc Amer.
Abstract: Recognition of the importance of soil compaction is increasing, but instrument cost, measurement repeatability, and data interpretation limit its measurement on agricultural and rangelands. The dynamic penetrometer described here follows American Society of Agricutlural Engineers standards, but replaces the proving ring with a strike plate, a shaft extension, and a sliding hammer. The penetrometer cone is pushed into the soil by successive hammer blows. Penetration resistance is calculated as the work by the soil needed to stop cone movement divided by the penetration distance. The work by the soil is defined as the kinetic energy of the hammer when it impacts the strike plate. Construction cost is approximately $100 to $150. The standard drop height and hammer mass ensure measurements are consistent between operators.
Hervas J, Barredo JI, Rosin PL, Pasuto A, Mantovani F and Silvano S (2003), "Monitoring landslides from optical remotely sensed imagery: the case history of Tessina landslide, Italy", Geomorphology., August, 2003. Vol. 54(1-2), pp. 63-75.
Abstract: Collecting information on landslide occurrence and activity over wide areas is a crucial task for landslide hazard assessment. Field techniques, despite being very precise, are usually not sufficient to achieve this goal, since they mostly provide point-based measurements. Mainly because of its synoptic view and its capability for repetitive observations, optical (visible-infrared) remotely sensed imagery acquired at different dates and at high spatial resolution can be considered as an effective complementary tool for field techniques to derive such information. An image-processing method to map and monitor landslide activity using multitemporal optical imagery is proposed. The method entails automatic change detection of suitably pre-processed (geometrically registered and radiometrically normalised) sequential images, followed by thresholding into landslide-related change pixels. Subsequent filtering based on the degree of rectangularity of regions can also be considered to eliminate pixel clusters corresponding to man-made land use changes. The application of this method is illustrated in the complex Tessina landslide in the Eastern Italian Alps. It has focused on discriminating the effects of a major reactivation that occurred in 1992, hence inferring the dynamics of the landslide at that time. Although the method has been devised for optical remote sensing imagery in general, in the absence of high-resolution satellite imagery covering that period, digital images derived by scanning existing aerial photograph diapositives at I-m pixel size have been used. The method is able to classify image pixels according to landslide activity conditions. (C) 2003 Elsevier Science B.V. All rights reserved.
Herz K (1973), "Beitrag zur Theorie der landschaftsanalytischen Maßstabsbereiche", Petermanns Geographische Mitteilungen. Vol. 117, pp. 91-96.
Abstract: When the landscape unities of the earth are arranged in a hierarchic way, it should be possible to describe heterogeneous unities (structures) of one stage of order as homogeneous unities (elements) of the next·higher stage of order. This transformation (translation into the sphere of the next smaller scale) must be reversible. Transformation can only be applied to the genetic unity of elements which is always to be recognized at the specific rule of equipment, arrangement and frequency (conception of struoture); the structure is always charaoteri7:ed by unitary oonditions of differentiation representing its general correlation of features (conception of the superordinate element).
Starting from these considerations, ways of the solution to the definition of the scale specific contents of the components of landscape and to the deduction of methods of transformation are discussed.
Highland L and Bobrowski P (2008), "The landslide handbook – A guide to understanding landslides. U.S. Geological Survey Circular 1325" Reston, Virginia , pp. 129. U.S. Geological Survey.
Hilker N, Badoux A and Hegg C (2009), "The Swiss flood and landslide damage database 1972-2007", Natural Hazards and Earth System Sciences. Vol. 9(3), pp. 913-925.
Abstract: In Switzerland, floods, debris flows, landslides and rockfalls cause damage every year affecting property values, infrastructure, forestry and agriculture. As population and settled areas have increased, the damage potential has also become greater. Information about natural hazard events that caused any damage is needed for hazard mapping and further decision making. This is why the Swiss Federal Research Institute WSL has been systematically collecting information on flood and mass movement damage in a database since 1972. The estimated direct financial damage as well as fatalities and injured people have been documented using press articles as the main source of information. The database can provide answers to questions related to the temporal and spatial distribution of damage, natural hazard processes and the corresponding weather conditions. This study describes the data collection methods used and the key analyses of data from 1972 to 2007. Furthermore, the benefits and drawbacks of the database are discussed. In Switzerland, naturally triggered floods, debris flows, landslides and rockfalls have caused financial damage amounting to nearly 8000 million Euros in total within the last 36 years (taking inflation into account). These processes have mainly affected pre- and central alpine regions and their total costs of damage are dominated by a few major events. Nearly one quarter of the costs result from August 2005 when large parts of Northern Switzerland were affected by flooding. We must assume that major events like this are not unique and that similar events will occur again in future.
Hilker N, Badoux A and Hegg C (2009), "Unwetterschäden in der Schweiz im Jahre 2008", Wasser Energie Luft. Vol. 101(2), pp. 95-100.
Abstract: Die im Jahr 2008 entstandenen Unwetterschäden beliefen sich auf rund 23 Mio. CHF und lagen weit unter der durchschnittlichen Schadenssumme der Jahre 1972 bis 2007, die teuerungsbereinigt knapp 370 Mio. CHF beträgt. Noch schadenärmer war lediglich das Jahr 1989. 2008 kam es zu keinem Todesfall durch Unwetter. Nur drei Grossereignisse verursachten Schäden von mehr als 2 Mio. CHF: Am schadenreichsten war das Gewitter vom 10. Juni, das vor allem in den Kantonen Zürich, Zug und Thurgau Überschwemmungen auslöste. Ein weiteres Gewitter betraf am 29. Juni hauptsächlich Mesocco GR, wo ein Murgang die Kantonsstrasse und mehrere Häuser verschüttete. Der Juni erwies sich denn auch als schadenreichster Monat des Jahres. Vom 12. bis 15. Juli wurden primär die Kantone Tessin und Graubünden durch andauernde Regenfälle in Mitleidenschaft gezogen. Im Jahr 2008 führten Gewitter zu mehr als 50% der Gesamtschadenssumme.
Hilker N, Hegg C and Zappa M (2008), "Unwetterschäden in der Schweiz 1972-2007. Mit besonderer Betrachtung des August-Hochwasser 2005", In Proc. of the XI International Congress Interpraevent 2008, Dornbirn. Dornbirn Vol. 1, pp. 99-110.
Abstract: Die Forschungseinheit "Gebirgshydrologie und Wildbäche" der Eidgenössischen Forschungsanstalt WSL sammelt seit 1972 systematisch Informationen über Unwetterschäden in einer Datenbank. Berücksichtigt werden Schäden durch Hochwasser, Murgänge, Rutschungen und Felsbewegungen. Innerhalb von 36 Jahren kam es in der Schweiz zu einem Gesamtschaden von knapp 13 Milliarden CHF4 (teuerungsbereinigt). Rund ein Viertel dieser Schäden entstand im August 2005, als weite Teile der Schweiz von grossflächigen Überschwemmungen betroffen waren. Die durch das Unwetter entstandenen finanziellen Schäden wurden eingehend dokumentiert, analysiert und mit früheren Ereignissen verglichen.
Hiura H (1988), "Hazard mapping in use of surface slide transition model", In Proc. of the VI International Congress Interpraevent 1988, Graz. Graz Vol. 1, pp. 297-313.
Abstract: Sediment yield produced by frequent surface slides on the mountain slopes of granitic rocks become as dangerous as those produced by gigantic landlides or large scale slope failures, because of the high frequency of occurrence in a basin in spite of the dimensions. After the investigation of the yearly fluctuation of the number of occurrances by the interpretation of aerial photographs, the author has recognized that the occurrence of surface slides in the future could be estimated by the Weibull Distribution Function. In this paper, the results of prediction of the occurrences of surface slides using this function are presented where the hazardous zones which will suffer from the sediment disaster are indicated on the topographical maps.
Hochschwarzer M (2009), "Vergleich von Simulationsmodellen zur Reichweitenabschätzung alpiner Murgänge". Thesis at: Universität für Bodenkultur Wien.
Abstract: Die zerstörerische Tätigkeit von Wildbachprozessen in alpinen Regionen bedroht Menschen und deren Einrichtungen. Die Modellierung betroffener Flächen und Objekte stellt einen wichtigen Schritt in der Bewertung dieser Naturgefahren dar. Modelle zur Bestimmung der Reichweite, der Auslauflänge und des Ablagerungsverhaltens von Murgängen liefern Grundlagen zur Erstellung von Gefahrenzonenplänen und zur Planung anderer Schutzmaßnahmen.
Das Ziel der Arbeit ist es, die neu entwickelten zweidimensionalen Simulationsprogramme TopRunDF und TopFlowDF anzuwenden und mit den auf dem Voellmy-Ansatz basierenden Programmen RAMMS und FLATModel, mit denen schon erfolgreich Murgänge simuliert werden konnten, zu vergleichen. TopRunDF beruht auf dem empirischen Zusammenhang von Ereignisvolumen und abgelagerter Fläche und einem stochastischen Modellierungsverfahren, der Monte Carlo Simulation. TopFlowDF hat zudem den dynamischen Ansatz von Takahashi (1991) zur Berechnung der eindimensionalen Auslauflänge integriert. Acht ausgewählte dokumentierte Ereignisse werden simuliert und die „best-fit“–Simulationen miteinander verglichen. Zudem werden auf den zur Verfügung stehenden Datensatz von 38 südtiroler Ereignissen eindimensionale Modelle angewandt. Es werden zwei empirische, volumsbezogene Ansätze zur Berechnung der Reichweite verwendet, ein für Murgänge neu entwickeltes Modell zur Bestimmung der Auslauflänge, das rein auf topografischen Zusammenhängen beruht und der etablierte Takahashi-Ansatz zur Berechnung der Auslauflänge. Die Resultate werden verglichen, analysiert und es können gewisse Zusammenhänge bei der Betrachtung bestimmter Parameter geschlossen werden.
Hofierka J, Parajka J, Mitasova H and Mitas L (2002), "Multivariate interpolation of precipitation using regularized spline with tension", Transactions in GIS. Vol. 6(2), pp. 135-150. Wiley Online Library.
Abstract: Regularized Spline with Tension (RST) is an accurate, flexible and efficient method for multivariate interpolation of scattered data. This study evaluates its capabilities to interpolate daily and annual mean precipitation in regions with complex terrain. Tension, smoothing and anisotropy parameters are optimized using the cross-validation technique. In addition, smoothing and rescaling of the third variable (elevation) is used to minimize the predictive error. The approach is applied to data sets from Switzerland and Slovakia and interpolation accuracy is compared to the results obtained by several other methods, expert-drawn maps and measured runoff. The results demonstrate that RST performs as well or better than the methods tested in the literature. The incorporation of terrain improves the spatial model of precipitation in terms of its predictive error, spatial pattern and water balance.
Höfle B and Rutzinger M (2011), "Topographic airborne LiDAR in geomorphology: A technological perspective", Zeitschrift Fur Geomorphologie., March, 2011. Vol. 55, pp. 1-29. Gebruder Borntraeger.
Abstract: Airborne LiDAR, also referred to as Airborne Laser Scanning, is widely used for high-resolution topographic data acquisition with sub-meter planimetric and vertical accuracy. This contribution gives a review of recent developments of LiDAR systems (e.g. full-waveform LiDAR) and advances in data processing and analysis for geomorphological applications. An overview of applications in geomorphology and related fields using different LiDAR data products (e.g. Digital Terrain Model and 3D point cloud) is given, indicating a great variety of fields of applications and data analysis approaches. These applications range from visual interpretation. of LiDAR derivatives (e.g. shaded relief map) to semi-automatic geomorphological mapping and fully automatic object detection (e.g. surface discontinuities). A quantitative analysis of the temporal trend of peer-reviewed journal publications confirms the increased consideration of airborne LiDAR data for mapping, modeling and exploiting Earth surface processes and landforms. Almost 50 % of the papers of the last 15 years were published in the last two years 2008 and 2009. Airborne LiDAR technology is developing rapidly leading to both a great opportunity and challenge for integrating new technological developments into existing workflows and stimulating new innovative approaches.
Hölbling D, Füreder P, Antolini F, Cigna F, Casagli N and Lang S (2012), "A Semi-Automated Object-Based Approach for Landslide Detection Validated by Persistent Scatterer Interferometry Measures and Landslide Inventories", Remote Sensing. Vol. 4(5), pp. 1310-1336.
Abstract: Geoinformation derived from Earth observation (EO) plays a key role for detecting, analyzing and monitoring landslides to assist hazard and risk analysis. Within the framework of the EC-GMES-FP7 project SAFER (Services and Applications For Emergency Response) a semi-automated object-based approach for landslide detection and classification has been developed. The method was applied to a case study in North-Western Italy using SPOT-5 imagery and a digital elevation model (DEM), including its derivatives slope, aspect, curvature and plan curvature. For the classification in the object-based environment spectral, spatial and morphological properties as well as context information were used. In a first step, landslides were classified on a coarse segmentation level to separate them from other features with similar spectral characteristics. Thereafter, the classification was refined on a finer segmentation level, where two categories of mass movements were differentiated: flow-like landslides and other landslide types. In total, an area of 3.77 km² was detected as landslide-affected area, 1.68 km² were classified as flow-like landslides and 2.09 km² as other landslide types. The outcomes were compared to and validated by pre-existing landslide inventory data (IFFI and PAI) and an interpretation of PSI (Persistent Scatterer Interferometry) measures derived from ERS1/2, ENVISAT ASAR and RADARSAT-1 data. The spatial overlap of the detected landslides and existing landslide inventories revealed 44.8% (IFFI) and 50.4% (PAI), respectively. About 32% of the polygons identified through OBIA are covered by persistent scatterers data.
Hönegger M (2008), "Veränderung der Almwirtschaft in Salzburg und altes Erfahrungswissen am Beispiel einer Alm im Lessachtal/Lungau". Thesis at: University of Natural Resources and Life Sciences, Vienna.
Abstract: This diploma thesis deals with changes of mountain pasture management in Salzburg, especially in the region Lungau, and its effects on landscape, society, culture and biodiversity. A further topic is traditional and ethnobotanical knowledge related to mountain pasture management. The Gralatialm, which was abandoned for 40 years and has been managed again since 2000, has been selected as case study. The development and changes of mountain pasture management were documented by analysis of data collected by Statistics Austria and AMA (Agricultural Market Austria). The case study aimed at a comprehensive documentation of the landscape, vegetation and management and its changes since 50 years. The pasture areas were classified into pasture types relating to the degree of preference by the cattle and by the intensity of grazing. Landscape and vegetation have changed so that ferns (Thelypteris limbosperma, Athyrium distentifolum), Alpine roses (Rhododendron ferrugineum) and other pasture weeds have spread. Traditional ecological and ethnobotanical knowledge relating to mountain pasture management still exists, but is not practised any more, because its importance has decreased.
Horton P, Jaboyedoff M, Rudaz B and Zimmermann M (2013), "Flow-R, a model for susceptibility mapping of debris flows and other gravitational hazards at a regional scale", Natural Hazards and Earth System Sciences. Vol. 13(4), pp. 869-885.
Abstract: The development of susceptibility maps for debris flows is of primary importance due to population pressure in hazardous zones. However, hazard assessment by process-based modelling at a regional scale is difficult due to the complex nature of the phenomenon, the variability of local controlling factors, and the uncertainty in modelling parameters. A regional assessment must consider a simplified approach that is not highly parameter dependant and that can provide zonation with minimum data requirements. A distributed empirical model has thus been developed for regional susceptibility assessments using essentially a digital elevation model (DEM). The model is called Flow-R for Flow path assessment of gravitational hazards at a Regional scale (available free of charge under www.flow-r.org) and has been successfully applied to different case studies in various countries with variable data quality. It provides a substantial basis for a preliminary susceptibility assessment at a regional scale. The model was also found relevant to assess other natural hazards such as rockfall, snow avalanches and floods. The model allows for automatic source area delineation, given user criteria, and for the assessment of the propagation extent based on various spreading algorithms and simple frictional laws. We developed a new spreading algorithm, an improved version of Holmgren's direction algorithm, that is less sensitive to small variations of the DEM and that is avoiding over-channelization, and so produces more realistic extents. The choices of the datasets and the algorithms are open to the user, which makes it compliant for various applications and dataset availability. Amongst the possible datasets, the DEM is the only one that is really needed for both the source area delineation and the propagation assessment; its quality is of major importance for the results accuracy. We consider a 10 m DEM resolution as a good compromise between processing time and quality of results. However, valuable results have still been obtained on the basis of lower quality DEMs with 25 m resolution.
Horton P, Schaefli B, Mezghani A, Hingray B and Musy A (2006), "Assessment of climate-change impacts on alpine discharge regimes with climate model uncertainty", Hydrological Processes., June, 2006. Vol. 20(10), pp. Int Assoc of Hydrol Sci; Int Commis on Snow and Ice.
Abstract: This study analyses the uncertainty induced by the use of different state-of-the-art climate models on the prediction of climate-change impacts on the runoff regimes of 11 mountainous catchments in the Swiss Alps having current proportions of glacier cover between 0 and 50%. The climate-change scenarios analysed are the result of 19 regional climate model (RCM) runs obtained for the period 2070-2099 based on two different greenhouse-gas emission scenarios (the A2 and B2 scenarios defined by the Intergovernmental Panel on Climate Change) and on three different coupled atmosphere-ocean general circulation models (AOGCMs), namely HadCM3. ECHAM4/OPYC3 and ARPEGE/OPA. The hydrological response of the study catchments to the climate scenarios is simulated through a conceptual reservoir-based precipitation-runoff transformation model called GSM-SCCONT. For the glacierized catchments, the glacier surface corresponding to these future scenarios is updated through a conceptual glacier surface evolution model. The results obtained show that all climate-change scenarios induce. in all catchments, an earlier start of the snowmelt period, leading to a shift of the hydrological regimes and of the maximum monthly discharges. The mean annual runoff decreases significantly in most cases. For the glacierized catchments, the simulated regime modifications are mainly due to an increase of the mean temperature and the corresponding impacts on the snow accumulation and melting processes. The hydrological regime of the catchments located at lower altitudes is more strongly affected by the changes of the seasonal precipitation. For a given emission scenario. the simulated regime modifications of all catchments are highly variable for the different RCM runs. This variability is induced by the driving AOGCM but also in large part by the inter-RCM variability. The differences between the different RCM runs are so important that the predicted climate-change impacts for the two emission scenarios A2 and B2 are overlapping. Copyright (C) 2006 John Wiley & Sons, Ltd.
Hovius N, Stark CP and Allen PA (1997), "Sediment flux from a mountain belt derived by landslide mapping", Geology., March, 1997. Vol. 25(3), pp. 231-234.
Abstract: In humid uplands landsliding is the dominant mass wasting process. In the western Southern Alps of New Zealand landslides are scale invariant and have a power-law magnitude frequency distribution. Independent studies from other regions suggest that this is a general property of landsliding. This observation is of critical importance to the evaluation of the impact of events of different length scales over different time intervals on landscape evolution. It is particularly useful when estimating regional geomorphic rates, because it constrains the frequency and overall significance of extreme events, which cannot otherwise be evaluated. By integrating the complete response of the system, we estimate the regional denudation rate due to landsliding to be 9 +/- 4 mm yr(-1). Sediment discharge from the western Southern Alps is dominated by landslide-derived material.
Howard AD (1965), "Geomorphological Systems - Equilibrium and Dynamics", American Journal of Science. Vol. 263(4), pp. 302-&.
Abstract: The historical record contained within landforms and the tendency of land forms toward equilibrium, with the processes acting upon them are not, as it might seem, contradictory; both facets may be encompassed within the systems approach to geomorphology. Landform features may be considered as open systems of complex behavior Equilibria in geomorphology may arise in several types of system environment relationships, and all adjustments of landforms to changes in the environment may be regarded as tending to ward an equilibrium state. The influence of a past process having acted upon a geomorphic system is proportional to the intensity and duration of its action but inversely proportional to the elapsed time since its action. That is to say, the amount of information within land forms about their historical changes decreases the more remote the past. Some landform features reflect only recent changes of environment, whereas others yield a certain amount of information about the more distant past.
Tectonic movements largely control the intensity of erosion but are not reflected in a simple manner through individual slopes and gradients of the landforms. Many slope relationships and terrace features previously ascribed to tectonic action actually result from geologic controls or climatic change. An areal uniformity of landform parameters is characteristic of regions of the same tectonic unit, homogeneous geology, and equivalent climate. Conversely, in areas of the same climatic and tectonic history, contrasts of land forms usually reflect areal variations of stratigraphy and structure, and certain landforms are characteristic of the boundary between different lithologies and structures.
von Hoyningen-Huene J (1981), "Die Interzeption des Niederschlags in landwirtschaftlichen Pflanzenbeständen" Arbeitsbericht Deutscher Verband für Wasserwirtschaft und Kulturbau, DVWK.
Abstract: Wegen der intensiven Inanspruchnahme des Grundwassers durch die Wasserwirtschaft zur Sicherstellung des Wasserbedarfes von Industrie und Bevölkerung sind die Bodenwasservorräte in manchen Gebieten der Bundesrepublik in beängstigendem Maß zurückgegangen. Deshalb konzentrieren sich viele hydrologische Untersuchungen auf die Grundwasserneubildung, bei der sich neben dem Niederschlag auch die Gebietsverdunstung als wesentlicher Bestimmungsfaktor erweist. Im Mittel über die verschiedenen Klimabereiche der Bundesrepublik verdunsten nämlich etwa ca. 65 % des Niederschlages, die restlichen 35 % aber fließen ab oder versickern in den Untergrund und füllen die Grundwasservorräte auf. Veränderungen im Wasserverlust durch Verdunstung wirken sich deshalb besonders markant in der Grundwasserneubildung aus, und es ist besonders wichtig, die Verdunstungsvorgänge intensiv zu untersuchen und nach einer Möglichkeit Ausschau zu halten, die "Wasserverluste" in diesem Sinne so zu beeinflussen, daß eine höhere Grundwasserspende als "Wasserertrag" resultiert.
Hruska R, Mitchell J, Anderson M and Glenn NF (2012), "Radiometric and Geometric Analysis of Hyperspectral Imagery Acquired from an Unmanned Aerial Vehicle", Remote Sensing. Vol. 4(9), pp. 2736-2752.
Abstract: In the summer of 2010, an Unmanned Aerial Vehicle (UAV) hyperspectral calibration and characterization experiment of the Resonon PIKA II imaging spectrometer was conducted at the US Department of Energy’s Idaho National Laboratory (INL) UAV Research Park. The purpose of the experiment was to validate the radiometric calibration of the spectrometer and determine the georegistration accuracy achievable from the on-board global positioning system (GPS) and inertial navigation sensors (INS) under operational conditions. In order for low-cost hyperspectral systems to compete with larger systems flown on manned aircraft, they must be able to collect data suitable for quantitative scientific analysis. The results of the in-flight calibration experiment indicate an absolute average agreement of 96.3%, 93.7% and 85.7% for calibration tarps of 56%, 24%, and 2.5% reflectivity, respectively. The achieved planimetric accuracy was 4.6 m (based on RMSE) with a flying height of 344 m above ground level (AGL).
Hsiao KH, Liu JK, Yu MF and Tseng YH (2004), "Change detection of landslide terrains using ground-based lidar data", In XXth ISPRS Congress. Istanbul, July, 2004. Vol. WG VII/5
Abstract: The topographic change has been estimated on basis of 3D laser data and aerial photogrammetric survey. The newly-developed, time-saving approach is by using airborne and ground-based lidar. A points-cloud of high precision and density distribution can be obtained in a few minutes for the sensitive latent landslide area. With a limited control survey of precise targets using GPS and total stations, multiple scans of ground-based laser scans can be registered together to form one cohesive 3D model. And, thus, overlaid the different period topographic data for estimating the changes of the target areas. Two cases are practiced in this study. For the first case, a river-bank landslide in Hsin-chu Hsien was scanned with 6 stations. Subsequently, they were registered and joined and re-sampled to a 2m grid for a comparison with information obtained by digitization of a 1/5000 topographic map. The second case is conducted to observe the deformation of a large-scaled dip-slope landslide of Jiu-fen-er mountain, which was triggered by the big shock of the Chi-Chi earthquake at Nantou County of central Taiwan on 1999/09/21. Control points are systematically distributed on the 1000m by 2000m landslide surface. Surveys are made by transits of total stations, GPS, and airborne lidar as well as ground-based lidar data. The terrain changes on ground surface have been detected in thus a scheme. It is found the largest change of height between the earthquake event is about 60m. The effectiveness of applying 3D laser scan is proved in this study.
Huabin W, Gangjun L, Weiya X and Gonghui W (2005), "GIS-based landslide hazard assessment: an overview", Progress in Physical Geography. Vol. 29(4), pp. 548-567. Sage Publications.
Abstract: In recent years, landslide hazard assessment has played an important role in developing land utilization regulations aimed at minimizing the loss of lives and damage to property. A variety of approaches has been used in landslide assessment and these can be classified into qualitative factor overlay, statistical models, geotechnical process models, etc. However, there is little work on the satisfactory integration of these models with geographic information systems (GIS) to support slope management and landslide hazard mitigation. This paper deals with several aspects of landslide hazard assessment by presenting a focused review of GIS-based landslide hazard assessment: it starts with a framework for GIS-based assessment of landslide hazard; continues with a critical review of the state of the art in using GIS and digital elevation models (DEM) for mapping and modelling landslide hazards; and concludes with a description of an integrated system for effective landslide hazard assessment and zonation incorporating artificial intelligence and data mining technology in a GIS-based framework of knowledge discovery.
Hübl J, Bunza G, Hafner K and Klaus W (2003), "ETAlp – Erosion, Transport in Alpinen Systemen"
Hübl J, Kienholz H and Loipersberger A (2002), "DOMODIS - Documentation of Mountain Desasters", In Schriftenreihe 1, Handbuch 1. Klagenfurt , pp. 1-39. Internationale Forschungsgesellschaft INTERPRAEVENT.
Huggel C, Claugue JJ and Korup O (2012), "Is climate change responsible for changing landslide activity in high mountains", Earth Surface Processes and Landforms. Vol. 37(1), pp. 77-91.
Abstract: Climate change, manifested by an increase in mean, minimum, and maximum temperatures and by more intense rainstorms, is becoming more evident in many regions. An important consequence of these changes may be an increase in landslides in high mountains. More research, however, is necessary to detect changes in landslide magnitude and frequency related to contemporary climate, particularly in alpine regions hosting glaciers, permafrost, and snow. These regions not only are sensitive to changes in both temperature and precipitation, but are also areas in which landslides are ubiquitous even under a stable climate. We analyze a series of catastrophic slope failures that occurred in the mountains of Europe, the Americas, and the Caucasus since the end of the 1990s. We distinguish between rock and ice avalanches, debris flows from de-glaciated areas, and landslides that involve dynamic interactions with glacial and river processes. Analysis of these events indicates several important controls on slope stability in high mountains, including: the non-linear response of firn and ice to warming; three-dimensional warming of subsurface bedrock and its relation to site geology; de-glaciation accompanied by exposure of new sediment; and combined short-term effects of precipitation and temperature. Based on several case studies, we propose that the following mechanisms can significantly alter landslide magnitude and frequency, and thus hazard, under warming conditions: (1) positive feedbacks acting on mass movement processes that after an initial climatic stimulus may evolve independently of climate change; (2) threshold behavior and tipping points in geomorphic systems; (3) storage of sediment and ice involving important lag-time effects.
Hungr O (1995), "A Model For the Runout Analysis of Rapid Flow Slides, Debris Flows, and Avalanches", Canadian Geotechnical Journal., August, 1995. Vol. 32(4), pp. 610-623. Natl Research Council Canada.
Abstract: Runout analyses are used for risk assessment and design of remedial measures against rapid landslides such as debris flows, debris avalanches, rockslide avalanches, large-scale liquefaction failures, and slides of fill and mining waste. A continuum model has been developed to simulate the characteristics of these phenomena. The model is based on a Lagrangian solution of the equations of motion and allows the selection of a variety of material theologies, which can vary along the slide path or within the slide mass. It also allows for the internal rigidity of relatively coherent slide debris moving on a thin liquefied basal layer. The effects of lateral confinement are accounted for in a simplified manner. The model, is shown to compare favourably with results of controlled laboratory experiments and other analytical tools for several different materials and problem configurations. Examples of the practical use of the model to predict the runout of coal mine waste flow slides and flows of liquefied granular tailings are presented.
Hungr O, Evans SG, Bovis MJ and Hutchinson JN (2001), "A review of the classification of landslides of the flow type", Environmental & Engineering Geoscience., August, 2001. Vol. 7(3), pp. 221-238.
Abstract: As a result of the widespread use of the landslide classifications of Varnes (1978), and Hutchinson (1988), certain terms describing common types of flow-like mass movements have become entrenched in the language of engineering geology. Example terms include debris flow, debris avalanche and mudslide. Here, more precise definitions of the terms are proposed, which would allow the terms to be retained with their original meanings while making their application less ambiguous. A new division of landslide materials is proposed, based on genetic and morphological aspects rather than arbitrary grain-size limits. The basic material groups include sorted materials: gravel, sand, silt, and clay, unsorted materials: debris, earth and mud, peat and rock. Definitions are proposed for relatively slow non-liquefied sand or gravel flows, extremely rapid sand, silt or debris flow slides accompanied by liquefaction, clay flow slides involving extra-sensitive clays, peat flows, slow to rapid earth flows in nonsensitive plastic clays, debris flows which occur in steep established channels or gullies, mud flows considered as cohesive debris flows, debris floods involving massive sediment transport at limited discharges, debris avalanches which occur on open hill slopes and rock avalanches formed by large scale failures of bedrock.
Hutchinson J (1968), "The Encyclopedia of Geomorphology. Encyclopedia of Earth Sciences Series" Vol. 3, pp. 688-695. Reinhold Book Corporation.
Hutchinson J (1984), "Methods of Locating Slip Surfaces In Landslides", Geographical Journal. Vol. 150(JUL), pp. 261-261.
Abstract: The importance of locating the slip surfaces of landslides is emphasized in connection with their investigation and instrumentation, their analysis and their stabilization.
The available methods are divided into two groups, those applicable only to moving landslides and those applicable to stationary ones. The first group comprises inferences from surface movement observations, direct measurements of sub-surface displacements, and geoacoustic sensing. In the second group the methods reviewed include in situ observations from access holes, observations on recovered samples and surface and sub-surface geophysical techniques.
It is concluded that it is advisable to employ a variety of methods and to pursue first the more easily accessible and hence more cheaply gained information. It should also be borne in mind that multiple slip surfaces often exist and that it is important to ensure that the lowest of these is found. An extensive list of references is provided.
Hutchinson JN (1988), "General Report: Morphological and geotechnical parameters of landslides in relation to geology and hydrogeology", In Landslides, Proc 5th Int. Symp. On Landslides. Lausanne, Switzerland Vol. 1, pp. 3-35. Balkema, Rotterdam.
Abstract: The paper reviews the range of sub-aerial mass movements on slopes under the headings of rebound, creep, sagging of mountain slopes, landslides, debris movements of flow-like form, topples, falls and complex slope movements. As far as possible, the various types are related to their controlling geological and hydrogeological features. An orthodox geotechnical classification of slope movements involving shearing is then briefly outlined and some aspects of this and the above review are discussed.
Ibbeken H and Schleyer R (1986), "Photo-sieving: A method for grain-size analysis of coarse-grained, unconsolidated bedding surfaces", Earth Surface Processes and Landforms. Vol. 11(1), pp. 59-77. John Wiley & Sons, Ltd.
Abstract: The photo-sieving method enables the grain-size analysis of particles > 10 mm from unconsolidated openwork bedding surfaces. The accuracy is equal to the machine-sieving method. The sediment surface is photographed in the field using a camera stand. The enlarged print is digitized for computer processing by tracing the outlines of the pebbles. From the size and shape of the projection area of the individual pebble images the computer determines the ellipsoids of revolution, classifies these ellipsoids, and establishes their grain-size distribution in percentage by weight. Thus photo-sieving differs distinctly from point-counting techniques. With the aid of photo-sieving, the surface grain-size distributions of larger sedimentary systems may be regularly mapped. Alluvial fans, braided rivers, both onshore and offshore coasts or areas of relict sediments and manganese nodules are suitable for this method.
Ibsen M and Brunsden D (1996), "Landslide recognition. Identification, Movement and Causes" Chichester , pp. 64-77. Wiley.
Ibsen M, Brunsden D, Bromhead E and Collison A (1996), "Landslide recognition. Identification, Movement and Causes" Chichester , pp. 78-84. Wiley.
Ibsen ML and Brunsden D (1996), "The nature, use and problems of historical archives for the temporal occurrence of landslides, with specific reference to the south coast of Britain, Ventnor, Isle of Wight", Geomorphology., April, 1996. Vol. 15(3-4), pp. Int Assoc Geomorphologists.
Abstract: The purpose of this paper is to describe and evaluate the nature of the European historical archives which are suitable for the assessment of the temporal occurrence and forecasting within landslides studies, using the British south coast as an example. The paper is based upon the British contribution to the Environment programme EPOCH, 1991-1993. A primary requirement of a research programme on process occurrence is to determine the event frequencies on as many time and space scales as possible. Thus, the analysis of archives is, potentially, an essential preliminary to the study of the temporal occurrence of landslide events. The range of such data sources extends from isolated, fortuitously dated sites from the Quaternary assemblage, through inferred event impacts using dendrochronology or lichenometric time series to historical records of causal factors such as rainfall data and more recently, deliberately recorded packages of cumulative or continuous data. Most countries have extensive historical sources which may be of considerable value in establishing the characteristics of geomorphological processes. These include narrative in literature, prints and other artwork, terrestrial and aerial photographs, remote sensing series, newspapers, incidental statements and scientific journals and reports. There are numerous difficulties in accessing, extracting, organising, databasing and analysing such data because they are not usually collated for scientific use. Problems involve such incalculable errors as: the experience, training and conscientiousness of the observer; the editing and recording process; judging the validity of the data used and the haphazard nature of recorded events in time and space. Despite these difficulties, such data do yield a record which adds to the representative temporal sample at a level above some threshold reporting position. It therefore has potential for specific statistical analysis. An example of a reasonable temporal landslide record is the data base of the Ventnor complex on the Isle of Wight initially established in 1991 by Geomorphological Services Limited (GSL), now of Rendel Geotechnics, and supplemented by the collections of the first author. The record displays an increase in landslide events over the present century, due probably to increasing technology and awareness of hazard and the development of process geomorphology. However, the landslide record was subsequently correlated with the Ventnor precipitation series. This indicated that wet year sequences usually gave rise to significant landslide events. The increasing variability and number of rainfall events predicted by various climatic units, e.g. the Hadley Centre, may therefore indicate a fundamental increase in landslide events in the future.
Ibsen ML and Casagli N (2004), "Rainfall patterns and related landslide incidence in the Porretta-Vergato region, Italy", Landslides., July, 2004. Vol. 1(2), pp. 143-150.
Abstract: An analysis of landslide occurrence in the low permeability terrain of Porretta-Vergato, Italy, related to prolonged rainfall patterns is presented. Data sets collected over nearly a century are statistically analysed. The pattern of the landslide hazard is considered and related to precipitation at the basin scale in order to enhance the understanding between the two parameters and assess their temporal changes, as well as interrelationships. Landslide incidence generally follows the periodic pattern of precipitation with a lag of approximately six months, which is believed to relate to the time necessary for the ground water to reach a critical level to initiate slope failure. There also appears to be a two-stage pattern of precipitation which induces most landslides: a preparatory period, where the landslide is destabilized and conditioned for slope failure, followed by a more intense period of rainfall that triggers or provokes the event. These initial findings point to the need for further studies to verify such unstable situations.
Imran J, Harff P and Parker G (2001), "A numerical model of submarine debris flow with graphical user interface", Computers & Geosciences., July, 2001. Vol. 27(6), pp. 717-729.
Abstract: A 1-D numerical model of the downslope spreading of a finite-source subaqueous debris Row is presented. The model incorporates the Bingham, Herschel-Bulkley, and bilinear theologies of viscoplastic fluids. Any of these theologies can be selected by the user. The layer-integrated conservation equations of mass and momentum balance are solved in a Lagrangian framework using an explicit finite difference scheme. The flow is assumed to remain laminar throughout the computation. Starting from an initial parabolic shape, the debris mass is allowed to collapse and propagate on a given topography. The code is written in the visual basic programming language and has a graphical user interface. The required input parameters can be specified interactively, and the propagation of the debris Bow can be viewed as the solution proceeds. The user interface for the software is described in detail. Simulated results from different theological models are compared. (C) 2001 Elsevier Science Ltd. All rights reserved.
Imran J, Parker G, Locat J and Lee H (2001), "1D numerical model of muddy subaqueous and subaerial debris flows", Journal of Hydraulic Engineering-asce., November, 2001. Vol. 127(11), pp. 959-968.
Abstract: A 1D numerical model of the downslope flow and deposition of muddy subaerial and subaqueous debris flows is presented. The model incorporates the Herschel-Bulkley and bilinear rheologies of viscoplastic fluid. The more familiar Bingham model is integrated into the Herschel-Bulkley rheological model. The conservation equations of mass and momentum of single-phase laminar debris flow are layer-integrated using the slender flow approximation. They are then expressed in a Lagrangian framework and solved numerically using an explicit finite difference scheme. Starting from a given initial shape, a debris flow is allowed to collapse and propagate over a specified topography. Comparison between the model predictions and laboratory experiments shows reasonable agreement. The model is used to study the effect of the ambient fluid density, initial shape of the failed mass, and theological model on the simulated propagation of the front and runout characteristics of muddy debris flows. It is found that initial failure shape influences the front velocity but has little bearing on the final deposit shape. In the Bingham model, the excess of shear stress above the yield strength is proportional to the strain rate to the first power. This exponent is free to vary in the Herschel-Bulkley model. When it is set at a value lower than unity, the resulting final deposits are thicker and shorter than in the case of the Bingham theology. The final deposit resulting from the bilinear model is longer and thinner than that from the Bingham model due to the fact that the debris flow is allowed to act as a Newtonian fluid at low shear rate in the bilinear model.
Iverson RM (2000), "Landslide triggering by rain infiltration", Water Resources Research., July, 2000. Vol. 36(7), pp. 1897-1910. Amer Geophysical Union.
Abstract: Landsliding in response to rainfall involves physical processes that operate on disparate timescales. Relationships between these timescales guide development of a mathematical model that uses reduced forms of Richards equation to evaluate effects of rainfall infiltration on landslide occurrence, timing, depth, and acceleration in diverse situations. The longest pertinent timescale is A/D-0, where D-0, is the maximum hydraulic diffusivity of the soil and A is the catchment area that potentially affects groundwater pressures at a prospective landslide slip surface location with areal coordinates x, y and depth H. Times greater than A/D-0 are necessary for establishment of steady background water pressures that develop at (x, y, H) in response to rainfall averaged over periods that commonly range from days to many decades. These steady groundwater pressures influence the propensity for landsliding at (x, y, H), but they do not trigger slope failure. Failure results from rainfall over a typically shorter timescale H-2/D-0 associated with transient pore pressure transmission during and following storms. Commonly, this timescale ranges from minutes to months. The shortest timescale affecting landslide responses to rainfall is root H/g, where g is the magnitude of gravitational acceleration. Postfailure landslide motion occurs on this timescale, which indicates that the thinnest landslides accelerate most quickly if all other factors are constant. Effects of hydrologic processes on landslide processes across these diverse timescales are encapsulated by a response function, R(t*) = root t*/pi exp (-1/t*) - erfc (1/root t*), which depends only on normalized time, t*. Use of R(t*) in conjunction with topographic data, rainfall intensity and duration information, an infinite-slope failure criterion, and Newton's second law predicts the timing, depth, and acceleration of rainfall-triggered landslides. Data from contrasting landslides that exhibit rapid, shallow motion and slow, deep-seated motion corroborate these predictions.
Iverson RM, Reid ME and LaHusen RG (1997), "Debris-flow mobilization from landslides", Annual Review of Earth and Planetary Sciences. Vol. 25, pp. 85-138. Annual Reviews Inc.
Abstract: Field observations, laboratory experiments, and theoretical analyses indicate that landslides mobilize to form debris flows by three processes: (a) widespread Coulomb failure within a sloping soil, rock, or sediment mass, (b) partial or complete liquefaction of the mass by high pore-fluid pressures, and (c) conversion of landslide translational energy to internal vibrational energy (i.e. granular temperature). These processes can operate independently, but in many circumstances they appear to operate simultaneously and synergistically. Early work on debris-flow mobilization described a similar interplay of processes but relied on mechanical models in which debris behavior was assumed to be fixed and governed by a Bingham or Bagnold rheology. In contrast, this review emphasizes models in which debris behavior evolves in response to changing pore pressures and granular temperatures. One-dimensional infinite-slope models provide insight by quantifying how pore pressures and granular temperatures can influence the transition from Coulomb failure to liquefaction. Analyses of multidimensional experiments reveal complications ignored in one-dimensional models and demonstrate that debris-flow mobilization may occur by at least two distinct modes in the field.
Iwahashi J, Kamiya I and Yamagishi H (2012), "High-resolution DEMs in the study of rainfall- and earthquake-induced landslides: Use of a variable window size method in digital terrain analysis", Geomorphology., June, 2012. Vol. 153, pp. 29-38.
Abstract: We undertake digital terrain analyses of rainfall- and earthquake-induced landslides in Japan, using high-resolution orthoimagery and Light Detection and Ranging (LiDAR) DEMs. Our aims are twofold: to demonstrate an effective method for dealing with high-resolution DEMs, which are often too detailed for landslide assessments, and to evaluate the topographic differences between rainfall- and earthquake-induced landslides. The study areas include the lzumozaki (1961 and 2004 heavy rainfalls), Niihama (2004 heavy rainfalls), Houfu (2009 heavy rainfalls), and Hanokidachi/Kurikoma-dam regions (the 2008 M 7.2 lwate-Miyagi Nairiku earthquake). The study areas include 7,106 landslides in these five regions. We use two topographic attributes (the slope gradient and the Laplacian) calculated from DEMs in varying window sizes. The hit rates for statistical prediction of landslide cells through discriminant analyses are calculated using the two topographic attributes as explanatory variables, and the landslide inventory data as the dependent variable. In cases of surface failure, the hit rates are found to diminish when the window size of the topographic attributes is too large or too small, indicating that an optimal scale factor is key in assessing shallow landslides. The representative window sizes are approximately 30 m for shallow landslides; the optimal window size may be directly related to the average size of landslides in each region. We also find a stark contrast between rainfall- and earthquake-induced landslides. Rainfall-induced landslides are always most common at a slope gradient of 30, but the frequency of earthquake-induced landslides increases exponentially with slope gradient. We find that the Laplacian, i.e., the attributes of surface convexity and concavity, and the slope gradient are both important factors for rainfall-induced landslides, whereas earthquake-induced landslides are influenced mainly by slope steepness. (C) 2012 Elsevier B.V. All rights reserved.
Iwashima T and Yamamoto R (1993), "A statistical analysis of the extreme events: long-term trend of heavy daily precipitation", Journal of the Meteorological Society of Japan. Vol. 71, pp. 637-640.
Jaboyedoff M, Baillifard F, Couture R, Locat J and Locat P (2004), "New insight of geomorphology and landslide prone area detection using DEM", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 191-197. Taylor & Francis.
Abstract: The increasing precision of digital elevation models (DEM) makes it possible to perform more detailed and systematic morphological analysis. Using the orientation of each single cell, a DEM can be represented by a kind of 3D shaded relief map having one color for each dip and strike direction, thus permitting a very simple slope analysis.
Three-dimensional histograms represented on density stereonets make it possible to analyze and identify the main structures of a rock slope. From such a representation, it is easy to detect the main features of a relief such as the main joints set shaping a slope, a fault scarp limiting an unstable rock mass, or a landslide scarp. Large-scale fault analysis helps the interpretation with respect to the location of some rockslides.
Such an approach applied to rock slopes leads to the identification of the main potential failure mechanisms produced by discontinuities. Using these results, the areas where potential planar or wedge failure may occur can be detected by comparing sliding directions and relief orientations. The density of dangerous structures can be also estimated if the average discontinuity spacing and trace length are known, or determined using a DEM.
Volumes of rock instabilities can easily be determined using the discontinuity traces on the DEM that shaped the relief delimiting unstable rock masses. For soil slopes, the scarp as well as the bottom of the slope can be determined, making it possible to estimate the sliding surface and thus the volume of the unstable mass, using simple functions.
In the basement rock of the Swiss Alps, the fracturing is developed enough to define in certain locations around 50% of the slope orientation directly. Often the entire slope is dependent on the 2 or 3 main fractures sets. Active rock instabilities are often located in the neighborhood of the intersection of large faults, as it is suspected in the Cretaux rock-fall area (VS, Switzerland). In many cases, a depression of the relief is associated with such an intersection. These depressions can be detected by the subtraction of a smoothed upper level of topography from a DEM. Identification of spurs within depressions indicates the presence of an important mass within a highly erodible area.
The comparison of streams locations and directions – calculated using GIS routines, or mapped – with the orientations of faults shows a very good agreement in the gneissic rocks of the Mattertal and of the Rhône valley (VS, Switzerland). The streams 3D directions often belong to the plane defined by the main discontinuities shaping the relief.
The histograms of DEM orientation performed by rock types are different for one hill slope. The slope angle is dependent on both an apparent friction angle of the rock, as demonstrated in the Lourtier area (VS, Switzerland), and discontinuities. However, the discontinuities play different roles depending on the peak strength of rocks. Such simple DEM analyses make it possible to quickly identify unstable or potentially unstable rock masses. The increasing availability of DEM will make such methods very useful.
Jaboyedoff M, Baillifard F, Couture R, Locat J, Locat P and Rouiller JD (2004), "Toward preliminary hazard assessment using DEM topographic analysis and simple mechanic modeling", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 199-206. Taylor & Francis.
Abstract: The increasing availability of digital elevation models (DEM) makes it possible to perform quick slope hazard assessments using semi-automatic procedures. The main morphological and structural features of a landscape can, for example, be identified using a DEM, taking into account its mesh size.
The geomorphological concept of base level, which is defined by the lowest level that can be eroded by a stream, can be useful for landslide identification and hazard assessment. Assuming that erosion by landsliding can affect only a limited thickness of the slope – i.e. from 0 to approximately 50 m – during a period of 1,000 to 10,000 years, a short-term local base level is thus defined. This concept means that all slope volumes that are not supported at their bottom can slide rapidly or slowly down towards the valley.
The computation of the base level uses the streams as invariant levels of the topography. The base level is thus anchored to the lines defined by the streams. Depending on the position of the upper part of the streams compared to the crest, the highest crests of the mountain range can also be considered as invariant. At the term scale of landslide activity, only rock-falls can affect the flanks of the crest. Large landslides occur rarely, because of the low force involved: only large landslides affecting the entire slope can affect crests. If necessary, an erosion function can be used to undercut the slope in order to cause its destabilization.
The calculation of the short-term local base level is derived from the procedure used to trace the background of a physical signal such as an X-Ray diffraction spectrum. Different possibilities which can be divided into two categories exist: 1) static procedures, which converge to a base limiting short term local base level, and 2) dynamic approaches that take erosion processes leading to a dynamic base level depending on the duration of the process of “base level definition” into account.
Let us consider that all the slope volume located above the short-term local base level can slide on this base level surface. Different procedures allow to compute the “weight” of the pixels (volume in excess above the base level) that potentially bring additional stress directly or indirectly on a pixel situated below. This leads to a first, simple approximation of the force acting on each pixel. The procedure for computing the involved pixels is based on a routine similar to the one for watershed analysis. The streams can be determined artificially by a routine, in order to avoid the problem of the sedimentation and/or to take into account the erosion by the streams.
Results indicate a good agreement between highly stressed zones and observed active rockfalls areas. In order to refine the hazard assessment, the highly stressed zones can be matched with other parameters such as fracturing or estimated water table level. The rock-fall activity indicated by active scree deposits must also be crossed with the results of the above method that indicates the high likelihood of large rock-falls.
Jaboyedoff M, Oppikofer T, Abellan A, Derron M-H, Loye A, Metzger R and Pedrazzini A (2010), "Use of LiDAR in landslide investigations: a review", Natural Hazards. Vol. 61(1), pp. 5-28.
Abstract: This paper presents a short history of the appraisal of laser scanner technologies in geosciences used for imaging relief by high-resolution digital elevation models (HRDEMs) or 3D models. A general overview of light detection and ranging (LIDAR) techniques applied to landslides is given, followed by a review of different applications of LIDAR for landslide, rockfall and debris-flow. These applications are classified as: (1) Detection and characterization of mass movements; (2) Hazard assessment and susceptibility mapping; (3) Modelling; (4) Monitoring. This review emphasizes how LIDAR-derived HRDEMs can be used to investigate any type of landslides. It is clear that such HRDEMs are not yet a common tool for landslides investigations, but this technique has opened new domains of applications that still have to be developed.
Jaedicke C, Solheim A, Blikra LH, Stalsberg K, Sorteberg A, Aaheim A, Kronhom K, Vikhamar-Schuler D, Isaksen K, Sletten K, Kristensen K, Barstad I, Melchiorre C, Hoydal OA and Mestl H (2008), "Spatial and temporal variations of Norwegian geohazards in a changing climate, the GeoExtreme Project", Natural Hazards and Earth System Sciences. Vol. 8, pp. 893-904.
Abstract: Various types of slope processes, mainly landslides and avalanches (snow, rock, clay and debris) pose together with floods the main geohazards in Norway. Landslides and avalanches have caused more than 2000 casualties and considerable damage to infrastructure over the last 150 years. The interdisciplinary research project "GeoExtreme" focuses on investigating the coupling between meteorological factors and landslides and avalanches, extrapolating this into the near future with a changing climate and estimating the socioeconomic implications. The main objective of the project is to predict future geohazard changes in a changing climate. A database consisting of more than 20 000 recorded historical events have been coupled with a meteorological database to assess the predictability of landslides and avalanches caused by meteorological conditions. Present day climate and near future climate scenarios are modelled with a global climate model on a stretched grid, focusing on extreme weather events in Norway. The effects of climate change on landslides and avalanche activity are studied in four selected areas covering the most important climatic regions in Norway. The statistical analysis of historical landslide and avalanche events versus weather observations shows strong regional differences in the country. Avalanches show the best correlation with weather events while landslides and rockfalls are less correlated. The new climate modelling approach applying spectral nudging to achieve a regional downscaling for Norway proves to reproduce extreme events of precipitation much better than conventional modelling approaches. Detailed studies of slope stabilities in one of the selected study area show a high sensitivity of slope stability in a changed precipitation regime. The value of elements at risk was estimated in one study area using a GIS based approach that includes an estimation of the values within given present state hazard zones. The ongoing project will apply the future climate scenarios to predict the changes in geohazard levels, as well as an evaluation of the resulting socioeconomic effects on the Norwegian society in the coming 50 years.
Jaiswal P, van Westen CJ and Jetten V (2011), "Quantitative assessment of landslide hazard along transportation lines using historical records", Landslides., September, 2011. Vol. 8(3), pp. 279-291.
Abstract: In this paper, a quantitative landslide hazard model is presented for transportation lines, with an example for a road and railroad alignment, in parts of Nilgiri hills in southern India. The data required for the hazard assessment were obtained from historical records available for a 21-year period from 1987 to 2007. A total of 901 landslides from cut slopes along the railroad and road alignment were included in the inventory. The landslides were grouped into three magnitude classes based on the landslide type, volume, scar depth, and run-out distance. To calculate landslide hazard, we estimated the total number of individual landslides per kilometer of the (rail) road for different return periods, based on the relationship between past landslides (recorded in our database) and triggering events. These were multiplied by the probability that the landslides belong to a given magnitude class. This gives the hazard for a given return period expressed as the number of landslides of a given magnitude class per kilometer of (rail) road. The relationship between the total number of landslides and the return period was established using a Gumbel distribution model, and the probability of landslide magnitude was obtained from frequency-volume statistics. The results of the analysis indicate that the total number of landslides, from 1- to 50-year return period, varies from 56 to 197 along the railroad and from 14 to 82 along the road. In total, 18 hazard scenarios were generated using the three magnitude classes and six return periods (1, 3, 5, 15, 25, and 50 years). The hazard scenarios derived from the model form the basis for future direct and indirect landslide risk analysis along the transportation lines. The model was validated with landslides that occurred in the year 2009.
Jakob M, Holm K, Lange O and Schwab JW (2006), "Hydrometeorological thresholds for landslide initiation and forest operation shutdowns on the north coast of British Columbia", Landslides., September, 2006. Vol. 3(3), pp. 228-238.
Abstract: Debris flows and debris avalanches are the most widespread and hazardous types of landslides on the British Columbia north coast. Triggered by heavy rain, they pose risks to forestry workers in sparsely developed regions. The scarcity of long-term quality rain gauges and the lack of weather radar information create significant challenge in predicting the timing of landslides, which could be used to warn and, when necessary, evacuate forestry personnel. Traditional methods to relate rainfall antecedents and rainfall intensity to known landslide dates have proven to be unsatisfactory in this study due to extreme spatial variability of rainfall, enhanced by the orographic effect and the scarcity of rain gauges in a very large area. This has led to an integration of meteorological variables in a landslide advisory system that classifies three types of approaching storms by the 850-mbar wind speed and direction, the occurrence of subtropical moisture flow, and the existence of a warm layer characterized by high thickness values of the 500- to 1,000-mbar pressure levels. The storm classification was combined with a 4-week antecedent rainfall and the 24-h rainfall measured near or in the watershed where logging operations are taking place. This system, once implemented, is thought to reduce loss of life, injury, and economic losses associated with forestry works in the study area.
Jasper K, Calanca P, Gyalistras D and Fuhrer J (2004), "Differential impacts of climate change on the hydrology of two alpine river basins", Climate Research., May, 2004. Vol. 26(2), pp. 113-129.
Abstract: Earlier impact studies have suggested that climate change may severely alter the hydrological cycle in alpine terrain. However, these studies were based on the use of a single or a few climate scenarios only, so that the uncertainties of the projections could not be quantified. The present study helps to remedy this deficiency. For 2 Alpine river basins, the Thur basin (1700 km(2)) and the Ticino basin (1515 km(2)), possible future changes in the natural water budget relative to the 1981-2000 (Thur) and 1991-2000 (Ticino) baselines were investigated by driving the distributed catchment model WaSiM-ETH with a set of 23 regional climate scenarios for monthly mean temperature (T) and precipitation (P). The scenarios referred to 2081-2100 and were constructed by applying a statistical-downscaling technique to outputs from 7 global climate models. The statistical-downscaling scenarios showed changes in annual mean T between +1.3 and +4.8degreesC and in annual total P between -11 and +11%, with substantial variability between months and catchments. The simulated overall changes in the hydrological water cycle were qualitatively robust and independent of the choice of a particular scenario. In all cases, the projections showed strongly decreased snow-pack and shortened duration of snow cover, resulting in time-shifted and reduced runoff peaks. Substantial reductions were also found in summer flows and soil-water availability, in particular at lower elevations. However, the magnitudes and certain aspects of the projected changes depended strongly on the choice of scenario. In particular, quantitative projections of soil moisture in the summer season and of the runoff in both the summer and autumn seasons were found to be quite uncertain, mainly because of the uncertainty present in the scenarios for P. Our findings clearly demonstrate that quantitative assessments of hydrological changes in the Alps using only a small number of scenarios may yield misleading results. This work strengthens our confidence in the overall results obtained in earlier studies and suggests distinct shifts in future Alpine hydrological regimes, with potentially dramatic implications for a wide range of sectors.
Jetten V, Govers G and Hessel R (2004), "Erosion models: Quality of spatial predictions", Hydrological Processes., February, 2004. Vol. 18(3), pp. 595-595.
Abstract: An overview is given on the predictive quality of spatially distributed runoff and erosion models. A summary is given of the results of model comparison workshops organized by the Global Change and Terrestrial Ecosystems Focus 3 programme, as well as other results obtained by individual researchers. The results concur with the generally held viewpoint in the literature that the predictive quality of distributed models is moderately good for total discharge at the outlet, and not very good for net soil loss. This is only true if extensive calibration is done: uncalibrated results are generally bad. The more simple lumped models seem to perform equally well as the more complex distributed models, although the latter produce more detailed spatially distributed results that can aid the researcher. All these results are outlet based: models are tested on lumped discharge and soil loss or on hydrographs and sedigraphs. Surprisingly few tests have been done on the comparison of simulated and modelled erosion patterns, although this may arguably be just as important in the sense of designing anti-erosion measures and determining source and sink areas. Two studies are shown in which the spatial performance of the erosion model LISEM (Limburg soil erosion model) is analysed. It seems that: (i) the model is very sensitive to the resolution (grid cell size); (ii) the spatial pattern prediction is not very good; (iii) the performance becomes better when the results are resampled to a lower resolution and (iv) the results are improved when certain processes in the model (in this case gully incision) are restricted to so called ‘critical areas’, selected from the digital elevation model with simple rules.
The difficulties associated with calibrating and validating spatially distributed soil erosion models are, to a large extent, due to the large spatial and temporal variability of soil erosion phenomena and the uncertainty associated with the input parameter values used in models to predict these processes. They will, therefore, not be solved by constructing even more complete, and therefore more complex, models. However, the situation may be improved by using more spatial information for model calibration and validation rather than output data only and by using ‘optimal’ models, describing only the dominant processes operating in a given landscape.
Jimenez-Peralvarez JD, Irigaray C, El Hamdouni R and Chacon J (2009), "Building models for automatic landslide-susceptibility analysis, mapping and validation in ArcGIS", Natural Hazards., September, 2009. Vol. 50(3), pp. 571-590.
Abstract: In this paper, ModelBuilder(TM) in ArcGIS (ESRI) has been applied to landslide-susceptibility analysis, mapping and validation. The models (scripts), available for direct downloading as an ArcGIS tool, allow landslide susceptibility to be computed in a given region, providing a landslide-susceptibility map, with the GIS matrix method, and ensuring a quality validation. The paper details the steps needed for the model-building process, enabling users to build their own models and to become more familiar with the tool. The susceptibility model leads the user first through a Digital Elevation Model (DEM), depicting the morphological and morphometric features of the study area, and then through a Digital Terrain Model (DTM), useful as a source of landslide-determinant factors, such as slope elevation, slope angle and slope aspect. In addition, another determinant factor is the lithological unit, independent of the DEM. Once the determinant landslide factors are reclassified and in a vectorial format, all the combinations between the classes of these factors are determined using the geoprocessing abilities of ArcGIS. The next step for the development of the landslide-susceptibility model consists of identifying the areas affected by a given surface of rupture (i.e. source area) in every combination of the determinant-factor classes. This step leads to the landslide matrix based on a previously georeferenced landslide database of the region, in which the slopes are distinguished into two simple classes: with or without landslides. In the last stage, to build a landslide-susceptibility model, the user computes the percentages of area affected by landslides in every combination of determinant factors. In the resulting landslide-susceptibility map a progressive zonation of areas or slopes increasingly prone to landslides is performed. A model for the validation of the resulting landslide-susceptibility map is also presented, based on the determination of the degree of fit, which is calculated from the cross tabulation between a set of landslides (not included in the susceptibility analysis) and the corresponding susceptibility map.
Jomelli V, Brunstein D, Deque M, Vrac M and Grancher D (2009), "Impacts of future climatic change (2070-2099) on the potential occurrence of debris flows: a case study in the Massif des Ecrins (French Alps)", Climatic Change., November, 2009. Vol. 97(1-2), pp. 171-191. Springer.
Abstract: In this paper we investigate the impacts of future climatic change on the occurrence of debris flows in the Massif des Ecrins (French Alps). Two distinct aspects are discussed: the impact of future climatic change on the evolution of the process, and changes in the spatial distribution. Three climate simulations are presented for the current period (1970-1999) and for future periods (2070-2099) using GCM ARPEGE CLIMAT model developed by Meteo-France. Simulated data are then statistically downscaled to obtain a higher spatial resolution. In the first step, we compare occurrence probabilities in the current period and in the next century. In the second step, we estimate which zones would be affected by the process in the future at the scale of the Massif des Ecrins. For the current period, the best model was obtained between debris flows and the number of days between June 15th and October 15th with more than 20 mm calculated either from observed meteorological or simulated data. Results of the ARPEGE model considering the A2 hypothesis (IPCC 2007) showed that the most significant climatic trends for the end of the century will be a decrease in intense rainy events and an increase in temperature. These trends are expected to reduce the occurrence of hill slope debris flows in the Massif des Ecrins. From a spatial point of view, the increase in temperature should result in a shift of the 0A degrees C isotherm to a higher elevation which, in turn, should result in a 20% reduction of the number of slopes affected by the process.
de Jong MG, de Graaff LW and Rupke J (1995), "Der Eisabbau im Vorderen Bregenzerwald und in den Nachbargebieten (Vorarlberg, Österreich; Bayern, Deutschland) nach dem letzteiszeitlichen Eishochstand", Jahrbuch der Geologischen Bundesanstalt. Vol. 138(1), pp. 27-54.
Jongmans D and Garambois S (2007), "Geophysical investigation of landslides : a review", Bulletin De La Societe Geologique De France. Vol. 178(2), pp. 101-112.
Abstract: In the last two decades, shallow geophysics has considerably evolved with the emergence of 2D spatial imaging, then 3D spatial imaging and now 4D time and space imaging. These techniques allow the study of the spatial and temporal variations of geological structures. This paper aims at presenting a current state-of-the-art on the application of surface geophysical methods to landslide characterization and focuses on recent papers (after 1990) published in peer-reviewed international journals. Until recently, geophysical techniques have been relatively little used for the reconnaissance of landslides for at least two main reasons. The first one is that geophysical methods provide images in terms of physical parameters, which are not directly linked to the geological and mechanical properties required by geologists and engineers. The second reason shown through this study probably comes from a tendency among a part of the geophysicists to overestimate the quality and reliability of the results. This paper gave the opportunity to review recent applications of the main geophysical techniques to landslide characterisation, showing both their interest and their limits. We also emphasized the geophysical image characteristics (resolution, penetration depth), which have to be provided for assessing their reliability, as well as the absolute requirements to combine geophysical methods and to calibrate them with existing geological and geotechnical data. We hope that this paper will contribute to fill the gaps between communities and to strength of using appropriate geophysical methods for landslide investigation.
Juarez A (1992), "Mathematische Modellierung des Erosionsprozesses als Grundlage zur Planung von Bodenschutzmaßnahmen", In Proc. of the VIII International Congress Interpraevent 1992, Bern. Bern Vol. 1, pp. 331-343.
Abstract: The identification of erosion hazard areas and the assessment of soil erosion rates are important for the planning of soil conservation measures. This report presents a description concerning the mathematical simulation of the erosion process considering the hydrological characteristics in tropical and subtropical areas, and taking into account the limitation in available data.
The new developed model EROFGM, which incorporates the interface of an already available watershed model with a soil erosion model, allows the simulation of the erosion process at single event basis. The model was applied to the basin of the Chixoy river in Guatemala with the following results:
- identification of soil erosion hazard areas,
- assessment of sediment transport at a selected point of the river and
- provision of planning basis for soil conservation measures (e. g. priorities, consequences of possible measures).
Kähni M, Klebinder K, Heller A and Graf A (2011), "Angewandte Geoinformatik 2011" , pp. 1-10. Wichmann Fachmedien.
Abstract: Gravitative Massenbewegungen stellen im Gebirgsraum vielerorts eine Bedrohung für die Gesellschaft dar. Sowohl aufgrund der direkten Gefährdung von Menschenleben, Siedlungsräumen und Infrastruktur als auch durch indirekte Einflüsse, wie beispielsweise der Bereitstellung von Geschiebe in Wildbächen, sind Massenbewegungen ein relevantes Thema im Arbeitsbereich der Naturgefahrenprävention.
Aufgrund der Komplexität der Abläufe aber auch durch die oftmals unmittelbaren Gefahren, welche im direkten Wirkungsbereich der Prozesse herrschen, bieten sich Methoden der Fernerkundung zu Analyse und Überwachungszwecken an. Im Zuge eines Monitoring Projektes konnte an einer Rutschung im Tiroler Wattental der Einsatz von terrestrischem Laserscanning (TLS) erprobt werden. Neben den flächigen Informationen zur Änderung der Geländeoberfläche, welche eine Analyse von Massendifferenzen erlauben, konnten Methoden erarbeitet werden, die Rückschlüsse über die Bewegung (Vektoren) erlauben. Für den Zeitraum April bis August 2010 konnten mittlere Bewegungsraten zwischen 1,5 und 3,6 cm/Tag festgestellt werden, dabei wurde ein Volumen von rund 1.300 m³ umgelagert. Der Einsatz Geographischer Informationssysteme unterstützt dabei sowohl bei der Gewinnung neuer Daten als auch in der Visualisierung des Prozessgeschehens und dessen Auswirkungen. Die Kombination aus Information zur Änderungen der Oberflächenmorphologie mit Bewegungsvektoren bietet Möglichkeiten zum erweiterten Verständnis von Prozessabläufen aber auch Potenzial im (Krisen)Monitoring.
Kajiyama A, Shiono K, Masumoto S and Fujita T (2005), "Basic theory of three-dimensional landslide modeling based on the logical model of geologic structure", Landslides., October, 2005. Vol. 2(3), pp. 212-220.
Abstract: Dynamic visualization of landslide cross-sections is important for understanding the structure and mechanism of landslide formation. Moreover, the modeling of geologic information plays an effective role in geo-hazard assessment and their mitigation. In this study, we developed the basic theory of a three-dimensional landslide modeling and applied it to the Nigawa landslide of the Hyogo Prefecture in central Japan. The construction of this model is based on the boundary surfaces of slump blocks and geologic units, and the hierarchical relationships between these surfaces. An application algorithm was validated and the model proved efficient in depicting the nature of landslides in the Nigawa area.
Kantner B (2001), "Kausalanalyse von ausgewählten Bodenparametern im Gebirge in Abhängigkeit von Landnutzung und Standortfaktoren". Thesis at: University of Innsbruck, Institute of Botany.
Abstract: Ziel dieser Arbeit war es zum einen, verschiedene bodenkundliche Parameter im Höhentransekt auf unterschiedlich bewirtschafteten Flächen zu untersuchen. Bei diesen Parametern handelt es sich um die Auflagehumusform, die Auflagehumusmächtigkeit und Auflagehumusmasse, sowie um den pH – Wert und das C/N-Verhältnis im Auflagehumus und Mineralboden und zuletzt noch um den organischen Substanzgehalt im Mineralboden. In einem weiteren Schritt wurde der organische Substanzgehalt für das gesamte INTERREG II - Projektgebiet modelliert und in einer flächendeckenden Vorhersagekarte graphisch dargestellt. Zur Vorhersage wurden die Bewirtschaftungs- und Standortparameter ausgewählt, die maßgeblich für die (Aus-) Bildung des organischen Substanzgehaltes verantwortlich sind.
Karabacak V, Altunel E and Cakir Z (2011), "Monitoring aseismic surface creep along the North Anatolian Fault (Turkey) using ground-based LIDAR", Earth and Planetary Science Letters., April, 2011. Vol. 304(1-2), pp. 64-70.
Abstract: We studied the surface creep along the North Anatolian Fault (NAF), one of the most seismically active structures of the eastern Mediterranean, by using a ground-based light detection and ranging (LIDAR) system at the Ismetpasa and Destek sections. Aseismic surface creep has been known to exist at Ismetpasa since the 1970s, but it has not been previously reported for the Destek site. Three manmade walls across the fault were monitored for 3 yrs between June 2007 and November 2009 using LIDAR The surveys revealed that a significant amount of aseismic strain is being continuously released along these sections of the NAF: 6.8-10.0 +/- 4.0 mm/yr and 9.1-10.1 +/- 4.0 mm/yr at two sites near Ismetpasa and 6.0-72 +/- 4.0 mm/yr at Destek. Despite this, these fault segments are still capable of generating large earthquakes since 50-70% of the yearly slip (i.e., 20-25 mm/yr) still accumulates on the fault, as was demonstrated by the well-known 20th century earthquake sequence of 1939-1999. (C) 2011 Elsevier B.V. All rights reserved.
Karl J (1961), "Blaikenbildung auf Allgäuer Blumenbergen", Jahrbuch des Vereins zum Schutze der Alpenpflanzen und -tiere. Vol. 26, pp. 55-62.
Keefer DK (1984), "Landslides Caused By Earthquakes", Geological Society of America Bulletin. Vol. 95(4), pp. 406-421.
Abstract: Data from 40 historical world-wide earthquakes were studied to determine the characteristics, geologic environments, and hazards of landslides caused by seismic events. This sample of 40 events was supplemented with intensity data from several hundred United States earthquakes to study relations between landslide distribution and seismic parameters. Fourteen types of landslides were identified in the earthquakes studied. The most abundant of these were rock falls, disrupted soil slides, and rock slides. The greatest losses of human life were due to rock avalanches, rapid soil flows, and rock falls. Correlations between magnitude (M) and landslide distribution show that the maximum area likely to be affected by landslides in a seismic event increases from approximately 0 at M = 4.0 to 500,000 km2 at M = 9.2.
Threshold magnitudes, minimum shaking intensities, and relations between M and distance from epicenter or fault rupture were used to define relative levels of shaking that trigger landslides in susceptible materials. Four types of internally disrupted landslides—rock falls, rock slides, soil falls, and disrupted soil slides—are initiated by the weakest shaking. More coherent, deeper-seated slides require stronger shaking; lateral spreads and flows require shaking that is stronger still; and the strongest shaking is probably required for very highly disrupted rock avalanches and soil avalanches.
Each type of earthquake-induced landslide occurs in a particular suite of geologic environments. These range from overhanging slopes of well-indurated rock to slopes of less than 1° underlain by soft, unconsolidated sediments. Materials most susceptible to earthquake-induced landslides include weakly cemented rocks, more-indurated rocks with prominent or pervasive discontinuities, residual and colluvial sand, volcanic soils containing sensitive clay, loess, cemented soils, granular alluvium, granular deltaic deposits, and granular man-made fill. Few earthquake-induced landslides reactivate older landslides; most are in materials that have not previously failed.
Keefer DK, Wilson RC, Mark RK, Brabb EE, Brown WM, Ellen SD, Harp EL, Wieczorek GF, Alager CS and Zatkin RS (1987), "Real-time Landslide Warning During Heavy Rainfall", Science., November, 1987. Vol. 238(4829), pp. 921-925.
Abstract: A real-time system for issuing warnings of landslides during major storms is being developed for the San Francisco Bay region, California. The system is based on empirical and theoretical relations between rainfall and landslide initiation, geologic determination of areas susceptible to landslides, real-time monitoring of a regional network of telemetering rain gages, and National Weather Service precipitation forecasts. This system was used to issue warnings during the storms of 12 to 21 February 1986, which produced 800 millimeters of rainfall in the region. Although analysis after the storms suggests that modifications and additional developments are needed, the system successfully predicted the times of major landslide events. It could be used as a prototype for systems in other landslide-prone regions.
Keijsers JGS, Schoorl JM, Chang KT, Chiang SH, Claessens L and Veldkamp A (2011), "Calibration and resolution effects on model performance for predicting shallow landslide locations in Taiwan", Geomorphology., October, 2011. Vol. 133(3-4), pp. 168-177.
Abstract: In this paper we optimise the spatially explicit prediction of landslide hazard, landslide triggering and subsequent movement downslope of materials for a mountainous catchment in Taiwan. The location prediction is optimised by subsequently adding three location parameters: rainfall distribution, land-use classes and DEM derived slopes. Then the three most important model parameters are calibrated to find the best prediction for both stable and unstable areas. The landslides predicted by the LAPSUS-LS model are compared with a landslide inventory to validate the output. The optimal model settings for the calibration area are then applied to a validation area. Results show that model performance can be improved by adding the spatial distribution of rainfall and by stratifying according to land-use classes. Landslide prediction is better with fine resolution DEMs, mainly because the local topography is smoothed in coarser resolutions. Although in general the amount of landslides is over-predicted, the overall performance indicates that the model is able to capture the important factors determining landslide location. Additional spatially distributed data such as regolith or soil depth and regeneration rates of the legacy effect can further enhance the model's prediction. (C) 2011 Elsevier B.V. All rights reserved.
Kelch G, Drexler O and Zech W (1977), "Über den Bodenabtrag im Kampenwandgebiet. Versuch einer quantitativen Erfassung der Zusammenhänge zwischen Bodenabtrag und den Faktoren Höhenlage, Exposition, Hangneigung, Muttergestein und Bodenutzung", Zeitschrift für Geomorphologie - Supplement. Vol. 28, pp. 134-147.
Abstract: In der Studie wird die räumliche Verbreitung von Blaiken (mit Zerstörung der Vegetation verbundener Bodenabtrag) im Gebiet der Kampenwand (Bayerische Alpen) und Ihre zeitliche Veränderung von 1961 bis 1973 quantitativ untersucht. Die wichtigsten Ergebnisse:
1. Die. Anzahl der Teilflächen mit Blaiken hat sich von 1961 bis 1973 geringfügig erhöht.
2. Blaikenblidung und -rückbildung stehen nicht im Gleichgewicht. Auf den Teilflächen, die bereits 1961 Blaiken aufwiesen, wurde bis 1973 eine allgemeine Tendenz zur Ausweitung der Vegetations- und Bodenschäden festgestellt.
3. Die Dynamik der Blaiken verläuft im Untersuchungsgebiet nicht einheitlich sondern variiert in Abhängigkeit von Höhenlage, Hangneigung, Exposition, Petrographie und Bodennutzung.
4. Der verstärkte mechanische Bodenabtrag wird durch einen vorausgehenden chemischen Humusabbau begünstigt.
Keller B (1996), "Lithofazies-Codes für die Klassifikation von Lockersedimenten", Mitteilungen der Schweizerischen Gesellschaft für Boden- und Felsmechanik. Vol. 132, pp. 5-12.
Abstract: Grossräumigere geologische, geotechnische und hydrogeologische Prognosen in Lockergesteinen basieren auf geologischen Modellen der sedimentären Architektur. Die Ergründung des im Modell dargestellten dreidimensionalen Aufbaus der Lockergesteine erfolgt durch die Analyse der Sedimente in natürlichen oder künstlichen Aufschlüssen.
Eine derartige Analyse basiert auf den drei nacheinander auszuführenden Schritten Beschreibung, Klassifikation und Interpretation, die schliesslich zum Modell führen (Fig. 1). Mit jedem dieser Arbeitsschritte nehmen Interpretation und Abstraktion zu, einhergehend mit einer stufenweisen Abnahme der Nachvollziehbarkeit. Für die Klassifikation, die Dokumentation und die Archivierung von Daten sind interpretierte Sedimenteinheiten unstatthaft, führen sie doch vermehrt zu Datenverlust und Fehlinterpretationen.
Für die Bearbeitung klastischer Sedimente bieten sich mehrere etablierte Klassifikationen an, die aus der Sicht der angewandten Geologie jeweils verschiedene Unzulänglichkeiten aufweisen. Diese Unzulänglichkeiten führen teilweise zu einem Datenverlust, wodurch die weiterführende Bearbeitung erschwert wird.
Mit der in diesem Artikel vorgestellten Klassifikation sollen diese Mängel bestehender Klassifikationen behoben werden. Bis anhin wurde sie an ca. 300 Bohrungen getestet und laufend verfeinert. Sie stellt keine Norm dar und versteht sich als Ergänzung zur bewährten geotechnischen USCS-Klassifikation. Hauptziele der vorgestellten Klassifikation sind:
- Festhalten der wichtigsten geologischen, geotechnischen und hydrogeologischen Merkmale bei möglichst wenig Interpretation.
- Gewährleistung einer überblickbaren, einprägsamen Gruppierung.
- Erleichterung der Interpretation von Lockergesteinen durch die Erfassung indikativer sedimentologischer und lithologischer Merkmale.
- Einfacher, aussage kräftiger Code als Grundlage für die computergestützte Auswertung und Archivierung.
Kenney C (1984), "Slope Instability" , pp. 27-65. Wiley-Interscience.
Abstract: The intention of this chapter is to provide an introduction to the properties and behaviours of soils, with the outlook biased towards mass movements on slopes. The most important soil property which relates to mass movements is shear strength, which is dealt with towards the end of this chapter and in Chapters 3 and 7. However, to understand more fully the shear strength behaviours of soils, it is necessary to understand the influences on shear strength of ground-water pressures and their variations with location and time. It is important to have an appreciation of the effects of stress history of a soil; that is, it is important to know whether or not the soil will dilate (increase in volume) or compress during shear displacement, because this will affect the shear strength behaviour. Also of importance is the matter of general soil characteristics which can be measured during the period of site investigation and used to describe subsurface conditions at a site. An example of a record of soil characteristics determined from a site investigation is presented in Figure 2.1, and reference to it should be made throughout this chapter. The chapter introduces a wide spectrum of ideas regarding the properties and behaviours of soils. The coverage will inevitably be incomplete; many soil mechanics textbooks have been written to cover basically the contents of this single chapter. Readers who may wish to delve further into some of the topics are encouraged to study the listed references.
Keppeler E and Brown D (1998), "Subsurface drainage processes and management impacts", In Proceedings of the Conference on Coastal Watersheds: The Caspar Creek Story. Ukiah, California, May 6, 1998, 1998. , pp. 25-34. Us Dept Agr, Forest Serv Pacific Sw Forest & Range Exptl Stn.
Abstract: Storm-induced streamflow in forested upland watersheds is linked to rainfall by transient, variably saturated flow through several different flow paths. In the absence of exposed bedrock, shallow flow-restrictive layers, or compacted soil surfaces, virtually all of the infiltrated rainfall reaches the stream as subsurface flow. Subsurface runoff an occur within micropores (voids between soil grains), various types of macropores (structural voids between aggregates, plant and animal-induced biopores), and through fractures in weathered and consolidated bedrock In addition to generating flow through the subsurface, transient rain events can also cause large increases in fluid pressures within a hillslope. If pore pressures Exceed stability limits of soils and shallow geologic materials, landslides and debris flows may result. Subsurface monitoring of pipeflows and pore pressures in unchanneled swales at North Fork Caspar Creek in the Jackson Demonstration State Forest began in 1985. Four sites have been established to investigate the effects of timber harvest (K1 and K2) and road building (E-road) for comparison with an unmanaged control drainage (M1). Flow through large soil pipes at these sites is highly transient in response to storm events, reaching peak discharges on the order of 100 to 1,000 L min(-1). Pore pressures at these sites also respond dynamically to transient rain events, but to dare have not exceeded slope stability limits. Most soil pipes cease flowing in the dry slimmer period and hillslope soil moisture declines to far below saturation, The clearcut logging and skyline-cable yarding of the K2 site resulted in dramatic increases in soil pipeflow and subsurface pore pressures. During the first 4 years after timber harvest, pore pressures increased 9 to 35 percent for the mean peak storm event in the control hll site. Peak soil pipeflow response wax far greater, increasing 400 percent in the 4-year postlogging period. These results suggest that the soil pipes are a critical component of subsurface hillslope drainage, acting to moderate the pore pressure response. As the subsoil matrix becomes saturated and pore pressures build, sail pipes efficiently, capture excess water and route it to the stream channel. This logging does not appear to have impaired the hillslope drainage function. Methods and results at the E-road site are quite different. Here, the mid-swale road construction and tractor yarding halle resulted in large changes in the pore pressure response. Positive pore pressures were negligible in the upper portion of this instrumented swale before disturbance. Subsequent to the road construction in May 1990, there was little indication of immediate impacts. But, after the completion of felling and tractor yarding in late summer 1991, dramatic changes in pore pressure response were observed beginning in hydrologic year 1993 and continuing to dare (1998). Largest pore pressure increases have occurred at sensor locations in and up slope of the road prism. Below the road, the response is muted. These data support previous studies documenting the profound effects of roading and tractor logging on watersheds and provide special insight into these effects for this region.
Khan SF, Kamp U and Owen LA (2013), "Documenting five years of landsliding after the 2005 Kashmir earthquake, using repeat photography", Geomorphology . Vol. 197(0), pp. 45-55.
Abstract: The 8 October 2005 Kashmir earthquake triggered thousands of landslides at different scales through the Hazara-Kashmir region of northern Pakistan. A landslide inventory was prepared within a few months after the earthquake, which included detailed photographs and studies of landslides at 164 locations. Photographs were retaken in 2006 at all the 2005 locations and at selected 68 landslide locations in 2007. In 2010, 123 of the 2005 landslide locations in the inventory were reexamined and photographed again. Existing literature predicted that extensive landsliding, particularly under wet conditions, was likely to occur in the region in the years immediately following the earthquake. Surprisingly, the repeat studies revealed that the total landslide area increased only slightly over the five-year period of study, even given a particularly heavy monsoon rainfall season in 2006, with 46% of the locations showing little or no increase and 10% showing a noticeable increase in landsliding; in 44% of the locations vegetation growth was significant or complete within the exposed landslide slip area. Many of the new or reactivated failures occurred along roads and rivers, particularly along steeper slopes. We conclude that the landscape returned to equilibrium within only a few years after the earthquake. Nevertheless, a potential for future slope instability and landsliding in the region still exists. Hence continuation of landslide monitoring and risk assessment is still important for hazard mitigation in this region.
Kiekbusch M and Siebenborn G (1996), "Der Standard Penetration Test (SPT)", Fachtechnik Brunnenbau 8. Vol. 47, pp. 20-25.
Abstract: Für die Bestimmung der Festigkeit von nichtbindigen Bodenarten für größere Einsatztiefen und Untersuchungen auf dem Wasser kommt der Standard Penetration Test (SPT) zum Einsatz. Er ermöglicht Untersuchungstiefen bis 100 m. Der Beitrag gibt praktische Hinweise und Erläuterungen zu dem Sondierverfahren und den Gerätemerkmalen und liefert ein speziell entwickeltes, hilfreiches Baustellenprotokoll.
Kienholz H (2002), "Early Warning Systems For Natural Disaster Reduction" Berlin, Heidelberg, New York , pp. 555-564. Springer.
Abstract: Mountain hazards, such as snow avalanches, rockfall, landslides, debris flows and torrential processes are responsible for disasters and catastrophes in mountainous areas every year. In many densely populated mountain regions, governmental agencies or the inhabitants themselves try to protect settlements and traffic routes by active measures (for example checkdams, etc.) and/or passive measures (for example hazard zoning, planning of evacuation, closing of railways and roads in case of acute danger). All these measures, especially those last mentioned require early warning. We should differentiate between early warning and observation measures, concerning either (1) the basic disposition of an area for dangerous processes (e.g. long-term preconditions, such as the general instability of a slope), or (2) the variable disposition (e.g. short-term state of the snow cover on an avalanche slope), or (3) the immediate effect of triggering events (i.e. thunderstorms triggering flash floods). There is a wide range of technical realisations of early warning systems for this. In many cases the most adequate solution is a traditional warning by watchful attendants; in other cases sophisticated electronic devices provide better safety. In all cases, however, it is essential that the early warning systems are very well applied by the involved experts, by the regional and local authorities, and by the population. The best concepts, the most sophisticated instrumentation are useless if the alert is not transmitted to the menaced people at the right time and if there is no accurate planning of emergency measures provided.
Kienholz H (1996), "Gefahrenkarten: Maßgebliche Parameter und Kriterien zur Festlegung von Intensitätsstufen", In Proc. of the VIII International Congress Interpraevent 1996, Garmisch-Partenkirchen. Garmisch-Partenkirchen Vol. 3, pp. 47-58.
Abstract: Für eine kohärente Praxis der Beurteilung von Naturgefahren werden in der Schweiz die Grundstätze für die Beurteilung und Bewertung der verschiedenen Naturgefahren harmonisiert. Die Bedeutung der Gefahrenstufen (Intensität, Wahrscheinlichkeit) wird ausgerichtet auf die Gefährdung von Menschen und erheblichen Sachwerten in Siedlungsgebieten. Angestrebt wird eine klare Gliederung nach Massgabe möglicher Konsequenzen für die Raumplanung in Verbots-, Gebots- und Hinweisbereiche. Ein wichtiges Anliegen ist die Festlegung der massgeblichen Parameter und Kriterien zur Definition der Intensitätsklassen für die verschiedenen, gleichwertig zu behandelnden Gefahrenarten. In Anlehnung an die Vorgaben in den "Richtlinien zur Berücksichtigung der Lawinengefahr bei raumwirksamen Tätigkeiten" (BFF, SLF, 1984) gilt es, den besonderen Bedürfnissen im Bereich der Bodenbewegungsgefahren und der Wassergefahren gerecht zu werden (zu letzteren vgl. PETRASCIIEK. 1996).
Kienholz H and Graf C (2000), "Vom Gelände zur Karte der Phänomene"
Abstract: Die Ereignisse des Jahres 1999 mit 1200 Schadenlawinen, 350 Hanginstabilitäten und den grossflächigen Überschwemmungen während des Maihochwassers haben deutlich vor Augen geführt, dass Naturgefahren auch für die schweizerische Bevölkerung und ihre Sachwerte eine grosse Bedrohung sein können. Gleichzeitig wurde während diesen Ereignissen die Bedeutung von Gefahrenkarten deutlich. Gefahrenkarten sind vor Ereignissen wichtige Instrumente für eine angepasste und verantwortbare Raumplanung. Aber auch während eines Ereignisses helfen sie den Einsatzdiensten bei der Wahl und Priorität von Evakuationszonen.
Das Erarbeiten von Gefahrenkarten beginnt mit der Erfassung und Dokumentation von Spuren früherer Ereignisse, den sogenannten „stummen Zeugen“. Daraus entsteht als erstes und unverzichtbares Produkt die „Karte der Phänomene“. Im Jahre 1995 haben das BUWAL und das Bundesamt für Wasserwirtschaft BWW (neu: Bundesamt für Wasser und Geologie BWG) die Publikation „Symbolbaukasten zur Kartierung der Phänomene“ mit einer harmonisierten Legende für Lawinen, Hochwasser und Massenbewegungen publiziert und darauffolgend verschiedene Feldkurse zum Thema durchgeführt.
Aufgrund der guten Erfahrungen und positiven Feedbacks haben wir beschlossen, ein zusätzliches Werkzeug zur Erstellung der „Karte der Phänomene“ zu erarbeiten. Dieses Werkzeug liegt nun in Form dieses Kompendiums vor. Es konnte mit einem massgebenden finanziellen Beitrag der Nationalen Plattform Naturgefahren PLANAT realisiert werden. Anhand von 40 Beispielen bietet die Publikation den Fachspezialisten Hilfe bei der Feldbeobachtung. Das Erstellen einer „Karte der Phänomene“ soll dadurch vereinfacht werden. Das Kompendium erhebt aber nicht den Anspruch, ein Lehrbuch zu sein.
Diese Kartierungshilfe ist das Ergebnis einer Zusammenarbeit zwischen Prof. Hans Kienholz (Projektleiter) und Christoph Graf, beide vom Geographischen Institut der Universität Bern, mit verschiedenen Bundes- und Kantonsbehörden, Universitäten und spezialisierten Firmen. Das Werkzeug soll all jenen dienen, die täglich mit der Erarbeitung von Gefahrenkarten oder Karten der Phänomene beschäftigt sind. Erfahrungen und Verbesserungsvorschläge sind willkommen und werden in eine nächste Fassung einfliessen.
Kienholz H and Krummenacher B (1995), "Symbolbaukasten zur Kartierung der Phänomene", Mitteilungen des Bundesamtes für Wasser und Geologie. Vol. 6, pp. 41.
Kienholz H, Perret S and Schmid F (2006), "Dokumentation von Naturereignissen - Feldanleitung" Innsbruck, Bern , pp. 64.. Ständiges Sekretariat der Alpenkonvention.
Kim D, Im S, Lee SH, Hong Y and Cha KS (2010), "Predicting the Rainfall-Triggered Landslides in a Forested Mountain Region Using TRIGRS Model", Journal of Mountain Science., March, 2010. Vol. 7(1), pp. 83-91.
Abstract: Landslides are natural disasters which can pose a serious threat to human and property in many areas around the world. The Transient Rainfall Infiltration and Grid-based Regional Slope-stability (TRIGRS) model was used to investigate the rainfall-induced shallow landslides in a forested mountain region, Korea. Various input data for TRIGRS model include time-varying rainfall, topographic characteristics, soil depth, material strength, and hydraulic properties. A series of calculations were conducted in determining the slope stability over the Jangheung region in Korea during the storm occurred on August 6, 1998. The results show that TRIGRS model captured about 64.1% of landslides that were extracted from the IKONOS2 imageries. The model demonstrated how the factor of safety changed with time during a storm considering both the transient and spatial responses of pore water pressure in its slope stability calculation.
Kincal C, Akgun A and Koca MY (2009), "Landslide susceptibility assessment in the Izmir (West Anatolia, Turkey) city center and its near vicinity by the logistic regression method", Environmental Earth Sciences., December, 2009. Vol. 59(4), pp. 745-756.
Abstract: A landslide susceptibility assessment for Izmir city (Western Turkey), which is the third biggest city of Turkey, was performed by a logistic regression method. A database of landslide characteristics was prepared using detailed field surveys. The major landslides in the study area are generally observed in the field, dominated by weathered volcanics, and 39.63% of the total landslide area is in this unit. The parameters of lithology, slope gradient, slope aspect, distance to drainage, distance to roads and distance to fault lines were used as variables in the logistic regression analysis. The effect of each parameter on landslide occurrence was assessed from the corresponding coefficients that appear in the logistic regression function. On the basis of the obtained coefficients, lithology plays the most important role in determining landslide occurrence and distribution. Slope gradient has a more significant effect than the other geomorphological parameters, such as slope aspect and distance to drainage. Using a predicted map of probability, the study area was classified into five categories of landslide susceptibility: very low, low, moderate, high and very high. Whereas 49.65% of the total study area has very low susceptibility, very high susceptibility zones make up 11.69% of the area.
King D, Stengel P, Jamagne M, Le Bas C and Arrouays D (2003), "Soil Mapping and soil monitoring: State of Progress and use in France"
Abstract: The Soil Survey Staff of France was founded in 1968 within INRA (National Institute of Agronomic Research) to ensure the co-ordination of the national soil mapping and monitoring programmes in France in a mainly agricultural context. During the last ten years, environmental problems have arisen and consequently led to an increase in the need for soil information. However, at the same time, the resources allocated to these programmes have been significantly reduced (King et al., 1999).
Considering this new context and the need for a good knowledge about the spatial distribution of soils, and the evolution of their properties, a new structure was created in 2001 to re-organise soil mapping and soil monitoring programmes in France. This new structure, called Scientific Group about Soils (GIS Sol) is constituted by the Ministries of Agriculture and Environment, the French Institute of Environment (IFEN), the organisation about environment protection and energy control (ADEME) and INRA. The Soil Survey Staff of France became then a single unit within INRA, the Infosol Unit, with the aim to realise the actions of the GIS Sol.
The objective of the GIS Sol is to develop an information system about the spatial distribution of French soils and the evolution of their properties. The two main priorities are the ‘Regional Soil Survey’ programme with the objective to have a complete coverage of France by 2010, and the development of a Soil Quality Monitoring Network.
This will be made possible with the help of some public and private organisations that are partners in these programmes: research institutes and universities, professional organisations, land development companies, etc.
The aim of this paper is to give an overview of the national soil mapping and soil monitoring programmes in France and their present state of progress.
Kirkpatrick LA and Weishampel JF (2005), "Quantifying spatial structure of volumetric neutral models", Ecological Modelling., August, 2005. Vol. 186(3), pp. 312-325.
Abstract: Neutral models in landscape ecology that have been used as a framework to analyze actual landscapes have been largely planar. However, the natural world is greater than two dimensions; hence, many ecological structures, e.g., forest canopies or coral reefs, are better represented by topographies or tomographies. Because pattern and process or structure and function are intertwined, it becomes necessary to develop methods to quantify these complex architectures. With the advent of remote sensing technologies such as lidars and sonars, that permit structural mapping of some of these systems, volumetric data are becoming more prevalent. In this study, we developed a suite of binary voxel-based neutral models that possessed random, anisotropic, and hierarchical properties. We then evaluated the extent to which fractal-derived measurements, i.e., lacunarity, the simple fractal dimension, and multifractal spectra, were able to discern among the constructed model types at two different densities (p = 0.02 and p = 0.05). Multifractal analysis, where spectra were defined by three parameters, was shown to be the most sensitive to the differences among the neutral structures. Lactunarity, defined by a single parameter, was shown to be fairly useful in discerning the structures. The simple fractal dimension was found to have limited capability. To more fully assess the ability of these and additional pattern recognition methods, better representations of natural morphologies need to be developed and analyzed. (c) 2005 Elsevier B.V. All fights reserved.
Klein-Tank A and Können G (2003), "Trends in indices of daily temperature and precipitation extremes in Europe, 1946-99", Journal of Climate., NOV, 2003. Vol. 16(22), pp. 3665-3680.
Abstract: Trends in indices of climate extremes are studied on the basis of daily series of temperature and precipitation observations from more than 100 meteorological stations in Europe. The period is 1946-99, a warming episode. Averaged over all stations, the indices of temperature extremes indicate ``symmetric'' warming of the cold and warm tails of the distributions of daily minimum and maximum temperature in this period. However, ``asymmetry'' is found for the trends if the period is split into two subperiods. For the 1946-75 subperiod, an episode of slight cooling, the annual number of warm extremes decreases, but the annual number of cold extremes does not increase. This implies a reduction in temperature variability. For the 1976-99 subperiod, an episode of pronounced warming, the annual number of warm extremes increases 2 times faster than expected from the corresponding decrease in the number of cold extremes. This implies an increase in temperature variability, which is mainly due to stagnation in the warming of the cold extremes. For precipitation, all Europe-average indices of wet extremes increase in the 1946-99 period, although the spatial coherence of the trends is low. At stations where the annual amount increases, the index that represents the fraction of the annual amount due to very wet days gives a signal of disproportionate large changes in the extremes. At stations with a decreasing annual amount, there is no such amplified response of the extremes. The indices of temperature and precipitation extremes in this study were selected from the list of climate change indices recommended by the World Meteorological Organization-Commission for Climatology (WMO-CCL) and the Research Programme on Climate Variability and Predictability (CLIVAR). The selected indices are expressions of events with return periods of 5-60 days. This means that the annual number of events is sufficiently large to allow for meaningful trend analysis in similar to50 yr time series. Although the selected indices refer to events that may be called ``soft'' climate extremes, these indices have clear impact relevance.
Kociu A, Kautz H, Tilch N, Grösel K, Heger H and Reischer J (2007), "Massenbewegungen in Österreich", Jah. Vol. 147, pp. 215-220.
Abstract: Since the foundation of the Department of Geological Engineering in 1978, the Geological Survey of Austria has the mission to catalogue and document geogenic natural hazards at a nationwide scale. In 2000, the latest amendment to the Austrian research law acknowledged the increasing occurrence of natural hazards and their economic consequences, and redefined the tasks of the Geological Survey of Austria. As a major focus of research activity, the project GEORIOS now compiles geogenic natural hazards in a GIS-supported database. The archives of the Department of Geological Engineering supply most of the data. For approximately 45,000 localities in Austria, information on geogenic natural hazards exists in analogue form. At present, a large part of the data has been digitized. In the future, data quality will be improved by revising inconsistencies with respect to geometry and content. Furthermore, metadata (figures, reports) will be added. The database will serve as a basis for information exchange between other institutes and organizations. The compilation of mass movements in Austria is publicly accessible via the internet (www.geologie.ac.at) in German and English language. However, the web application only features events such as slides, rock falls, or more complex mass movements, which have been published already in the media or the internet.
Konz N, Bänninger D, Nearing M and Alewell C (2009), "Does WEPP meet the specificity of soil erosion in steep mountain regions?", Hydrology and Earth System Sciences Discussions. Vol. 6(2), pp. 2153-2188.
Abstract: We chose the WEPP model (Water Erosion Prediction Project) to describe soil erosion in the Urseren Valley (central Switzerland) as it seems to be one of the most promising models for steep mountain environments. Crucial model parameters were determined in the field (slope, plant species, fractional vegetation cover, initial saturation level), by laboratory analyses (grain size, organic matter) or by the WEPP manual (rill- and interrill erodibility, effective hydraulic conductivity, cation exchange capacity). The quantification of soil erosion was performed on hill slope scale for three different land use types: meadows, pastures with dwarf shrubs and pastures without dwarf shrubs. Erosion rates for the vegetation period were measured with sediment traps between June 2006 and November 2007. Long-term soil erosion rates were estimated by measuring Cs-137 redistribution, deposited after the Chernobyl accident. In addition to the erosion rates, soil moisture and surface flow was additionally measured during the vegetation period in the field and compared to model output. Short-term erosion rates are simulated well whereas long term erosion rates were underestimated by the model. Simulated soil moisture has a parallel development compared to measured data from April onwards but a converse dynamic in early spring (simulated increase and measured decrease in March and April). The discrepancy in soil water during springtime was explained by delayed simulated snow cover melting. The underestimation of simulated long term erosion rates is attributed to alpine processes other than overland flow and splash. Snow gliding processes might dominate erosion processes during winter time. We assume that these differences lead to the general simulated underestimation of erosion rates. Thus, forcing erosion processes which dominate erosion rates in mountainous regions have to be implemented to WEPP for a successful application in the future.
Konz N, Baenninger D, Konz M, Nearing M and Alewell C (2010), "Process identification of soil erosion in steep mountain regions", Hydrology and Earth System Sciences. Vol. 14(4), pp. 675-686.
Abstract: Mountainous soil erosion processes were investigated in the Urseren Valley (Central Switzerland) by means of measurements and simulations. The quantification of soil erosion was performed on hill slope scale (2 center dot 20 m) for three different land use types: hayfields, pastures with dwarf shrubs and pastures without dwarf shrubs with three replicates each. Erosion rates during growing season were measured with sediment traps between June 2006 and November 2007. Long-term soil erosion rates were estimated based on Cs- 137 redistribution. In addition, soil moisture and surface flow were recorded during the growing season in the field and compared to model output. We chose the WEPP model (Water Erosion Prediction Project) to simulate soil erosion during the growing season. Model parameters were determined in the field (slope, plant species, fractional vegetation cover, initial saturation level), by laboratory analyses (grain size, organic matter) and by literature study. The WEPP model simulates sheet erosion processes (interrill and splash erosion processes, please note that no rill erosion occurs at our sites). Model output resulted in considerable smaller values than the measured erosion rates with sediment traps for the same period. We attribute the differences to observed random gravity driven erosion of soil conglomerates. The Cs-137 measurements deliver substantially higher mean annual erosion rates, which are most likely connected to snow cover related processes such as snow gliding and avalanche activities.
Konz N, Prasuhn V and Alewell C (2012), "On the measurement of alpine soil erosion", Catena., April, 2012. Vol. 91, pp. 63-71.
Abstract: The knowledge of soil erosion processes and especially soil erosion rates in alpine grassland regions is scarce due to the lack of detailed studies. The non-existence of validated methods which are suitable to quantify alpine soil erosion is one of the key issues for the limited process understanding. The aim of this study is to compare different methods and to conclude on suitability for the determination of alpine soil erosion. Furthermore, the advantages and disadvantages of the single measurement methods with regard to alpine basins are focused. We distinguish between sediment traps and sediment cups to determine erosion rates biweekly in 2007 and 2008, and Cesium-137 based measurements to measure long term erosion rates since 1986. The latter method integrates over a time span of 22 years. We investigate three different land cover types: hayfields, pasture with dwarf shrubs and pasture without dwarf shrubs in the Urseren Valley (Central Switzerland) with a mean slope steepness of 37. Sediment traps are suitable to quantify erosion rates during summer time. However, measurements are not possible during winter time. Sediment cups are an ideal tool for soil movement observation within the plot size but are limited to quantitative measurements. Cesium-137 investigations enable erosion quantification all-throughout-the-year but without identifying related processes. The combination of all three methods turns out to be useful for erosion quantification and process understanding. Mean monthly erosion rates during the vegetation periods 2007 and 2008 based on the sediment traps are between 0.006 t ha(-1) mo(-1) and 0.045 t ha(-1) mo(-1). These generally low erosion rates can be explained by a low overland flow of 0.5-1.8% of the measured precipitation. Cesium-137 based measurements yield mean annual erosion rates for the time span 1986-2008 between 8.3 t ha(-1) yr(-1) and 26 t ha(-1) yr(-1). We conclude that erosion rates on alpine grassland are dominated by snow driven processes during winter time. (C) 2011 Elsevier B.V. All rights reserved.
Konz N, Schaub M, Prasuhn V, Baenninger D and Alewell C (2009), "Cesium-137-based erosion-rate determination of a steep mountainous region", Journal of Plant Nutrition and Soil Science-zeitschrift Fur Pflanzenernahrung Und Bodenkunde., October, 2009. Vol. 172(5), pp. 615-622.
Abstract: Data on quantification of erosion rates in alpine grasslands remain scarce but are urgently needed to estimate soil degradation. We determined soil-erosion rates based on (137)CS in situ measurements. The method integrates soil erosion over the last 22 y (time after the Chernobyl accident). Measured erosion rates were compared with erosion rates modeled with the Universal Soil Loss Equation (USLE). The comparison was done in order to find out if the USLE is a useful tool for erosion prediction in steep mountainous grassland systems. Three different land-use types were investigated: hayfields, pasture with dwarf shrubs, and pasture without dwarf shrubs. Our test plots are situated in the Urseren Valley (Central Switzerland) with a mean slope steepness of 37 degrees. Mean annual soil-erosion rates determined with (137)CS of the investigated sites ranged between the minimum of 4.7 t ha(-1) y(-1) for pastures with dwarf shrubs to >30 t ha(-1) y(-1) at hayfields and pastures without dwarf shrubs. The determined erosion rates are 10 to 20 times higher compared to previous measurements in alpine regions. Our measurements integrated over the last 22 y, including extreme rainfall events as well as winter processes, whereas previous studies mostly reported erosion rates based on summer time and short-term rainfall simulation experiments. These results lead to the assumption that heavy-rainfall events as well as erosion processes during winter time and early spring do have a considerable influence on the high erosion amounts that were measured. The latter can be confirmed by photographs of damaged plots after snowmelt. Erosion rates based on the LISLE are in the same order of magnitude compared to (137)Cs-based results for the land-use type "pasture with dwarf shrubs". However, erosion amounts on hayfields and pasture without dwarf shrubs are underestimated by the LISLE compared to (137)Cs-based erosion rates. We assume that the underestimation is due to winter processes that cause soil erosion on sites without dwarf shrubs that is not considered by the USLE. Dwarf shrubs may possibly prevent from damage of soil erosion through winter processes. The USLE is not able to perform well on the affected sites. Thus, a first attempt was done to create an alpine factor for the LISLE based on the measured data.
Kosugi K, Yamakawa Y, Masaoka N and Mizuyama T (2009), "A Combined Penetrometer-Moisture Probe for Surveying Soil Properties of Natural Hillslopes", Vadose Zone Journal., February, 2009. Vol. 8(1), pp. 52-63.
Abstract: Information on spatial distributions of soil water content and mechanical strength is fundamental to hydrogeomorpho-logical studies in mountainous watersheds. For simultaneous measurements of soil water content, theta, and penetration resistance, N(c), of soil mantles on natural hillslopes, we developed a new type of combined penetrometer-moisture probe (CPMP). The new CPMP has a robust configuration to reduce the frequency of moisture probe breakdowns during penetration into gravelly and rocky natural soils, and it has a penetration depth of up to 552 cm, which is about four to 14times greater than the maximum measurable depth of any previous CPMP developed for agricultural soils. Laboratory calibrations and field validations showed that the CPMP succeeded in producing vertical distributions for theta and N(c) similar to those measured with conventional methods. The CPMP provided less time-consuming and less destructive measurements of theta profiles than conventional methods that require excavation of deep trenches. Because theta profiles consider the stratified characteristics of soil mantles as well as the depths of groundwater tables, the CPMP was more effective than the conventional cone penetrometer for surveying the hydrogeomorphological structure of soil mantles. The CPMP was successful in determining the spatial distributions of theta and N(c) in a headwater basin underlain by weathered granitic bedrock. From a direct comparison between two. and N(c) values measured on two different days at nearby points and the same depth, it was shown that N(c) tended to decrease when theta increased by more than 0.15.
Kraus K and Pfeifer N (1998), "Determination of terrain models in wooded areas with airborne laser scanner data", Isprs Journal of Photogrammetry and Remote Sensing., August, 1998. Vol. 53(4), pp. 193-203. Elsevier Science Bv.
Abstract: Large-scale terrain measurement in wooded areas was an unsolved problem up to now. Laser scanning solves this problem to a large extent. In this article, the-characteristics of laser scanning will be compared to photogrammetry with reference to a big pilot project. Laser scanning supplies data with a skew distribution of errors because a portion of the supplied points is not on the terrain but on the treetops. Thus, the usual interpolation and filtering has to be adapted to this new data type. We will report on the implementation of this new method. The results are in accordance with the expectations. The geomorphologic quality of the contours, computed from a terrain model derived from laser scanning, needs to be improved. Solutions are still to be found. (C) 1998 Elsevier Science B.V. All rights reserved.
Kreysler D, Nowy W, Poisel R and Preh A (2004), "Stabilization of landslide affected sections of the Second Vienna Water Main based on monitoring results", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 583-589. Taylor & Francis.
Abstract: The last one hundred kilometres of the Second Vienna Water Main run through several landslides of the Flysch-Zone of the Austrian Central Alps. Thus the supply system is constantly monitored by the municipal board of control (MA 31). Twice a year, after having been emptied the galleries are checked for any new cracks, which are immediately repaired if necessary. Inside the galleries convergence indicators have been installed in order to determine the deformations of the structure. Investigations by finite-difference models (UDEC) were used as the basis for determining the stability and the operational safety of the Second Vienna Water Main. In feasibility studies intensive drainage of the slopes was found to be the overall most suitable, effective and economic measure for the remediation of the affected sections. The monitoring measures after the extension of the drainage systems confirm the effectiveness of these measures.
Kringer K (2010), "Geomorphometric Analysis of Airborne Laserscanning data for Soil Mapping in an Alpine Valley Bottom". Thesis at: University of Innsbruck.
Kringer K, Tusch M, Geitner C, Rutzinger M, Wiegand C and Meißl G (2009), "Geomorphometric analyses of LiDAR digital terrain models as input for digital soil mapping", In Proceedings of Geomorphometry. Zurich, Switzerland, 31 August - 2 September, 2009. , pp. 74-81.
Kuriakose SL (2010), "Physically-based dynamic modelling of the effect of land use changes on shallow landslide initiation in the Western Ghats of Kerala, India". Thesis at: University of Twente.
Kuriakose SL (2006), "Effect of Vegetation on Debris Flow Initiation". Thesis at: International Institute for Geo-Information Science and Earth Observation Enschede.
Abstract: Debris flows, also referred to as mudslides, mudflows, or debris avalanches are a common type of fast-moving landslide that generally occurs during intense rainfall on water saturated soil. Vegetation is an important factor influencing the occurrance of rainfall-triggered landslides. The study attempts to numerically simulate the transient hydrological conditions and resultant slope instability conditions occurring in Tikovil River basin of Kerala, and thereby quantify the effect of vegetation on the initiation of debris flows in the region.
Kuriakose SL, van Beek LPH and van Westen CJ (2009), "Parameterizing a physically based shallow landslide model in a data poor region", Earth Surface Processes and Landforms., May, 2009. Vol. 34(6), pp. 867-881.
Abstract: Shallow landslides and consequent debris flows are an increasing concern in the Western Chats of Kerala, India. Their increased frequency has been associated with deforestation and unfavourable land-use practices in cultivated areas. In order to evaluate the influence of vegetation on shallow slope failures a physically based, dynamic and distributed hydrological model (STARWARS) coupled with a probabilistic slope stability model (PROBSTAB) was applied to the upper Tikovil River basin (55.6 km(2)). It was tuned with the limited evidence of groundwater conditions during the monsoon season of 2005 and validated against observed landslide activity in the hydrological year 2001-2002. Given the data poor conditions in the region some modifications to the original model were in order, including the estimation of parameters on the basis of generalized information from secondary sources, pedo-transfer functions, empirical equations and satellite remote sensing data. Despite the poor input, the model captured the general temporal and spatial pattern of instability in the area. Sensitivity analysis proved root cohesion, soil depth and angle of internal friction as the most dominant parameters influencing slope stability. The results indicate the importance of root cohesion in maintaining stability and the critical role of the management of rubber plantations in this. Interception and evapotranspiration showed little influence on the development of failure conditions. The study also highlights the importance of high resolution digital terrain models for the accurate mechanistic prediction of shallow landslide initiation. Copyright (C) 2009 John Wiley & Sons, Ltd.
Kuriakose SL, Devkota S, Rossiter DG and Jetten VG (2009), "Prediction of soil depth using environmental variables in an anthropogenic landscape, a case study in the Western Ghats of Kerala, India", Catena., October, 2009. Vol. 79(1), pp. 27-38.
Abstract: Soil (regolith) depth is a crucial input for modeling earth surface phenomena. However, most studies ignore its spatial variability. Techniques that map the spatial variability of soil depth are of three types: (1) physically-based; (2) empirico-statistical from environmental correlates; and (3) interpolation from point observations. In an anthropogenic landscape, soil depth does not depend primarily on natural processes, making it difficult to apply a physically-based approach. The present study compares empirico-statistical methods with geostatistical methods for predicting soil depth in such a landscape: Aruvikkal catchment (9.5 km(2)) in the Western Ghats of Kerala, India. Regression kriging applied on blocks of 20 m by 20 m using the environmental covariates elevation, slope, aspect, curvature, wetness index, land use and distance from streams. proved to be the best predictor of soil depth. This model explains 52% of the variability of soil depth in the catchment; with a prediction variance of 0.05 to 0.19. A Gaussian simulation was attempted fora more realistic visualization of the depth, as opposed to the smooth kriging prediction. The most important explanatory variable of soil depth in this landscape is land use. as expected from the strong human intervention. (C) 2009 Elsevier B.V. All rights reserved.
Kuriakose SL, Jetten VG, van Westen CJ, Sankar G and van Beek LPH (2008), "Pore Water Pressure As A Trigger of Shallow Landslides In the Western Ghats of Kerala, India: Some Preliminary Observations From An Experimental Catchment", Physical Geography., July, 2008. Vol. 29(4), pp. 374-386.
Abstract: The Western Ghats mountain chain of Kerala, India, is prone to landslides mainly caused by anthropogenic disturbances and very high rainfall amounts. Here, some initial observations on the apparent relationship among pore water pressure fluctuations, rainfall characteristics, and landslide initiation are presented based on monitoring in an experimental catchment in the upper Tikovil River basin. On June 21 and 22, 2007, continuous rain fell for over 10 hours with a total precipitation of 147 mm, causing three shallow landslides in the catchment. Measurements using piezometers in three hollows of the catchment indicate that the rain spell resulted in the development of high pore water pressure from the beginning of the storm that persisted through the time of occurrence of shallow landslides. The pore water pressure patterns in these monitored hollows are possible representatives of the pore water pressure pattern in the hollows where the landslides initiated. This similarity of response pattern enables such data to be used for the calibration and validation of physically based slope hydrology models coupled with slope stability models.
Kuriakose SL, Sankar G and Muraleedharan C (2009), "History of landslide susceptibility and a chorology of landslide-prone areas in the Western Ghats of Kerala, India", Environmental Geology., June, 2009. Vol. 57(7), pp. 1553-1568.
Abstract: Kerala is the third most densely populated state in India. It is a narrow strip of land, of which 47% is occupied by the most prominent orographic feature of peninsular India, The Western Ghats mountain chain. The highlands of Kerala experience several types of landslides, of which debris flows are the most common. They are called "Urul Pottal" in the local vernacular. The west-facing Western Ghats scarps that runs the entire extent of the mountain system is the most prone physiographic unit for landslides. The highlands of the region experience an annual average rainfall as high as 500 cm through the South-West, North-East and Pre-Monsoon showers. A survey of ancient documents and early news papers indicates a reduced rate of slope instability in the past. The processes leading to landslides were accelerated by anthropogenic disturbances such as deforestation since the early 18th century, terracing and obstruction of ephemeral streams and cultivation of crops lacking capability to add root cohesion in steep slopes. The events have become more destructive given the increasing vulnerability of population and property. Majority of mass movements have occurred in hill slopes > 20A degrees along the Western Ghats scarps, the only exception being the coastal cliffs. Studies conducted in the state indicates that prolonged and intense rainfall or more particularly a combination of the two and the resultant pore pressure variations are the most important trigger of landslides. The initiation zone of most of the landslides was typical hollows generally having degraded natural vegetation. A survey of post-landslide investigation and news paper reports enabled the identification of 29 major landslide events in the state. All except one of the 14 districts in the state are prone to landslides. Wayanad and Kozhikode districts are prone to deep seated landslides, while Idukki and Kottayam are prone to shallow landslides.
Laatsch W (1974), "Hangabtrag durch Schnee in den oberbayerischen Alpen und seine Begünstigung durch unpflegliche Almwirtschaft und Wildverbiß", Forstwissenschaftliches Centralblatt. Vol. 93, pp. 23-34.
Abstract: In früheren Aufsatzen wurde über Erosionsschäden und Bodenrutsche im Bereich der bayerischen Alpentäler berichtet (LAATSCH, 1971; GROTTENTHALER und LAATSCH, 1973). Der vorliegende Beitrag macht auf Gefahren und Schäden aufmerksam, die an steilen Hängen der höheren Berglagen zwischen rund 1200 m und 1900 m Höhe auftreten. Sowohl in den Wildbachtälern als auch in stark geneigten Hochlagen wird der beschleunigte Hangabtrag durch eine Summe verschiedener Faktoren hervorgerufen. Waldweide und Wildverbiss konnen in beiden Fällen eine beachtliche Rolle spielen.
Laatsch W (1971), "Bodenschutz im Bergwald des bayerischen Alpengebietes", Forstwissenschaftliches Centralblatt. Vol. 90, pp. 159-174.
Abstract: An vielen Stellen unserer Alpenwälder neigen die Hangböden und die unter ihnen liegenden Lockermassen zum Abrutschen, oder sie sind der schnellen erodierenden Wirkung der Hangwässer ausgesetzt. Dieser Hangabtrag kann dort, wo er in größerem Umfange auftritt, zur Überlastung der Wildbäche mit Geschiebe führen. Vermurungen und Hochwasserschäden gehen damit Hand in Hand. Das Wesen dieser Rutschungen und Erosionsformen, ihre Entstehung, Verbreitung und Bedeutung sei zunächst kurz geschildert. Dann soll auf die Faktoren eingegangen werden, welche einen beschleunigten Hangabtrag herbeiführen. Als Schlußfolgerungen aus den beschriebenen Fakten ergeben sich schließlich die möglichen Bekämpfungsmethoden.
Laatsch W and Baum U (1976), "Faktoren der Wald- und Bodenzerstörung durch Schnee in den Alpen", Agrochimica. Vol. 10(4-5), pp. 324-338.
Abstract: Die Schubkräfte sich bewegender Schneemassen können auf hochgelegenen Alpen-Steilhängen erhebliche Schäden an Waldbeständen und Hangböden hervorrufen. Nicht nur Lawinen und auf kurzer Bahn abrutschende Schneebretter sondern auch unmerklich langsame Bewegungen der geneigten Schneedecke üben nicht selten zerstörende Kräfte aus.
Laatsch W and Grottenthaler W (1973), "Labilität und Sanierung der Hänge in der Alpenregion des Landkreises Miesbach"
Abstract: Mit der folgenden Untersuchung wird eine neuartige Karte vorgelegt. Wir hoffen, daß sie als eine standortskennzeichnende Planungsunterlage für die Raumordnung und für die Alm- und Forstwirtschaft dienen kann. Sie zeigt, welche Flächen durch bestimmte Formen des beschleunigten Hangabtrags mäßig oder stark gefährdet sind, wenn sie nicht mit dichtem Wald bestockt sind. Im Abschnitt 4 der folgenden Erläuterungen wird auf zweckmäßige Wirtschaftsarten auf solchen Flächen eingegangen.
Laatsch W and Grottenthaler W (1972), "Typen der Massenverlagerung in den Alpen und ihre Klassifikation", Forstwissenschaftliches Centralblatt. Vol. 91, pp. 309-339.
Lacerda W, Ehrlich M and Fontoura S (2004), "Landslides: Evaluation and stabilization" Rio De Janeiro, Brazil, June 28 -July 2, 2004. Taylor & Francis.
Abstract: The Ninth International Symposium on Landslides (IS1:2004) was held in Rio de Janeiro, Brazil, from June 28th to July 2nd, 2004. Rio de Janeiro is a tropical city of 7 million inhabitants which stretches out over an area of some 1300 km2 along the seashore of the Atlantic Ocean. The city is spread between beautiful beaches and the Sierra do Mar range of mountains. The combination of sea and mountains gives the city a particu1ar and well-known beauty. Rio de Janeiro is the only city that encompasses a National Forest with waterfalls and a preserved environment, the Tijuca National Forest, open to the public all year round. The Sugar Loaf and the Corcovado Mountain and many other interesting spots are examples ofthis magnificent conspiracy ofmountain and sea.
Landslides play an important role in construction projects in Rio de Janeiro and other Brazilian cities. Residual and colluvium's soil slopes, besides rock boulders, play an important role in residential, industrial and civil projects in different areas in Brazil. This Symposium provided invaluable opportunities to those interested in presenting and discussing their recent experiences in the evaluation of landslide hazards and preventive and corrective measures. Practicing and consulting engineers and geologists, researchers, owners and construction managers, government officials, public and private contractors, equipment suppliers have had the opportunity to exchange their experiences in engineering works related to lands lide problems.
Seven major themes have been selected for the Symposium: Mapping and Geological Models in Landslide Hazards, Advances in Rock and Mine Slopes Design, Field Instrumentation and Laboratory Investigations, Pre-Failure Mechanics of Landslides in Soil and Rock, Mechanisms of Slow Active Landslides, Post-Failure Mechanics of Landslides and Stabilization Methods and Risk Reduction Measures. All invited lectures and panel contributions from eminent specialists and researchers and all teclmical papers that were presented at the Symposium are included in these two Proceedings volumes.
The Organizing Committee is very pleased with the positive response from the international scientific community to this important event and with all contributions made. Moreover, the Organizing Comrnittee wishes to express her sincere gratitude to the sponsoring organizations and companies for their financial support.
Lackinger B (1988), "Zum Problem der Gleitschneelawine", In Proc. of the VI International Congress Interpraevent 1988, Graz. Graz Vol. 3, pp. 205-226.
Abstract: Gleitschneelawinen entstehen bei ausgeprägtem Gleiten des Schnees, nachdem sich Risse geöffnet haben. Die komplexen Zusammenhange und die maßgebenden Faktoren ihres Anbruchs werden aufgezelgt. In einem Beobachtungsgebiet wurden Meßfelder und elne Meßstatlon eingerichtet. Über Meßverfahren (besonders Gleitgeschwindigkeit und Temperaturprofil) und Ergebnisse wird berichtet. Gegenüber publizierten Gleitgeschwindigkeiten ergaben slch teils wesentlich größere Werte. Die Geschwindigkeitsentwicklung während des Reißens der Schneedecke konnte gemessen werden. 25 dokumentierte Gleitschneelawinen sind mit topografischen, chronologischen und meteorologischen Daten und den Bildungsursachen in Tab. 1 erfaßt. 0°-Isothermie der Schneedecke spielte dabei eine wichtige Rolle. Aufgrund verschiedener Theorien über den Scherwiderstand zwischen Schnee und Boden wird ein Modell der Bruchphasen einer Gleitschneelawine entwIckelt. Die Risse entstehen durch unterschiedliche Einleitung der treibenden Schubspannungen in den Boden. Die inhomogenen Längsspannungen in der Schneedecke erreichen die Zugfestigkeit. Spannungsumlagerungen und andere Gleitverhaltnisse schaffen ein neues Gleichgewicht. Dle Lawine entsteht später durch einen Scherbruch am Boden infolge elnes Festigkeitsverlustes. Ein solcher kann durch einen begrenzten Wasserstau entstehen. Eine Parameterstudie ergab, daß die Abmessungen des bruchauslösenden Staus nur wenige Prozent der Lawinenfläche ausmachen.
Lahousse T, Chang KT and Lin YH (2011), "Landslide mapping with multi-scale object-based image analysis - a case study in the Baichi watershed, Taiwan", Natural Hazards and Earth System Sciences. Vol. 11(10), pp. 2715-2726.
Abstract: We developed a multi-scale OBIA (object-based image analysis) landslide detection technique to map shallow landslides in the Baichi watershed, Taiwan, after the 2004 Typhoon Aere event. Our semi-automated detection method selected multiple scales through landslide size statistics analysis for successive classification rounds. The detection performance achieved a modified success rate (MSR) of 86.5% with the training dataset and 86% with the validation dataset. This performance level was due to the multi-scale aspect of our methodology, as the MSR for single scale classification was substantially lower, even after spectral difference segmentation, with a maximum of 74 %. Our multi-scale technique was capable of detecting landslides of varying sizes, including very small landslides, up to 95 m(2). The method presented certain limitations: the thresholds we established for classification were specific to the study area, to the landslide type in the study area, and to the spectral characteristics of the satellite image. Because updating site-specific and image-specific classification thresholds is easy with OBIA software, our multi-scale technique is expected to be useful for mapping shallow landslides at watershed level.
Laliberte AS, Goforth MA, Steele CM and Rango A (2011), "Multispectral Remote Sensing from Unmanned Aircraft: Image Processing Workflows and Applications for Rangeland Environments", Remote Sensing., November, 2011. Vol. 3(11), pp. 2529-2551.
Abstract: Using unmanned aircraft systems (UAS) as remote sensing platforms offers the unique ability for repeated deployment for acquisition of high temporal resolution data at very high spatial resolution. Multispectral remote sensing applications from UAS are reported in the literature less commonly than applications using visible bands, although light-weight multispectral sensors for UAS are being used increasingly.. In this paper, we describe challenges and solutions associated with efficient processing of multispectral imagery to obtain orthorectified, radiometrically calibrated image mosaics for the purpose of rangeland vegetation classification. We developed automated batch processing methods for file conversion, band-to-band registration, radiometric correction, and orthorectification. An object-based image analysis approach was used to derive a species-level vegetation classification for the image mosaic with an overall accuracy of 87%. We obtained good correlations between: (1) ground and airborne spectral reflectance (R-2 = 0.92); and (2) spectral reflectance derived from airborne and WorldView-2 satellite data for selected vegetation and soil targets. UAS-acquired multispectral imagery provides quality high resolution information for rangeland applications with the potential for upscaling the data to larger areas using high resolution satellite imagery.
Lambrechtsen N and Hicks D (2001), "Soil intactness/erosion monitoring techniques - a literature review"
Abstract: The Regional Councils' Land Monitoring Group commissioned Ecological Research Associates to carry out a review of the New Zealand literature on techniques for monitoring soil intactness and soil erosion. The Ministry for the Environment [MfE] funded the review. Land monitoring is one of the requirements in the State of the Environment Reporting (SER) programme, carried out by councils and managed by the Ministry for the Environment, pursuant to Section 35 of the Resource Management Act 1991.
Since there is a vast literature on the topic of soil intactness/erosion, both New Zealand and overseas, we cannot claim that this review is comprehensive. We have focused on documents that discuss, or conta in examples of practical erosion measurement methods.
Lan HX, Lee CF, Zhou CH and Martin CD (2005), "Dynamic characteristics analysis of shallow landslides in response to rainfall event using GIS", Environmental Geology., January, 2005. Vol. 47(2), pp. 254-267.
Lang A, Moya J, Corominas J, Schrott L and Dikau R (1999), "Classic and new dating methods for assessing the temporal occurrence of mass movements", Geomorphology., October, 1999. Vol. 30(1-2), pp. 33-52.
Abstract: Establishing landslide chronologies is essential both for understanding causes of mass movements as part of fundamental geomorphological research, and for the assessment of landslide hazards as part of applied geomorphology. We discuss the applicability of different methods for determining landslide chronologies, frequencies and dynamics in relation to the type of material being dated, sampling location and type of mass movement. The emphasis is on the possibilities and limitations of the different dating methods. Established methods such as radiocarbon dating, lichenometry and dendrochronology are briefly discussed. The paper focuses, however, on (1) new analytical techniques like Accelerator Mass Spectrometry (AMS), Thermally Ionising Mass Spectrometry (TIMS) and laser fusion, which have led to significant improvements of established dating methods and on (2) new dating methods Like Optically-Stimulated-Luminescence (OSL) dating and Alpha-Recoil-Track (ART) dating. (C) 1999 Elsevier Science B.V. AU rights reserved.
Lanni C (2012), "Hydrological controls on the triggering of shallow landslides: from local to landscape scale". Thesis at: University of Trento.
Lanni C, Borga M, Rigon R and Tarolli P (2012), "Modelling shallow landslide susceptibility by means of a subsurface flow path connectivity index and estimates of soil depth spatial distribution", Hydrology and Earth System Sciences. Vol. 16(11), pp. 3959-3971.
Abstract: Topographic index-based hydrological models have gained wide use to describe the hydrological control on the triggering of rainfall-induced shallow landslides at the catchment scale. A common assumption in these models is that a spatially continuous water table occurs simultaneously across the catchment. However, during a rainfall event isolated patches of subsurface saturation form above an impeding layer and their hydrological connectivity is a necessary condition for lateral flow initiation at a point on the hillslope. Here, a new hydrological model is presented, which allows us to account for the concept of hydrological connectivity while keeping the simplicity of the topographic index approach. A dynamic topographic index is used to describe the transient lateral flow that is established at a hillslope element when the rainfall amount exceeds a threshold value allowing for (a) development of a perched water table above an impeding layer, and (b) hydrological connectivity between the hillslope element and its own upslope contributing area. A spatially variable soil depth is the main control of hydrological connectivity in the model. The hydrological model is coupled with the infinite slope stability model and with a scaling model for the rainfall frequency-duration relationship to determine the return period of the critical rainfall needed to cause instability on three catchments located in the Italian Alps, where a survey of soil depth spatial distribution is available. The model is compared with a quasi-dynamic model in which the dynamic nature of the hydrological connectivity is neglected. The results show a better performance of the new model in predicting observed shallow landslides, implying that soil depth spatial variability and connectivity bear a significant control on shallow landsliding.
Lanni C, McDonnell J, Hopp L and Rigon R (2013), "Simulated effect of soil depth and bedrock topography on near-surface hydrologic response and slope stability", Earth Surface Processes and Landforms., February, 2013. Vol. 38(2), pp. 146-159.
Abstract: This paper explores the effect of hillslope hydrological behavior on slope stability in the context of transient subsurface saturation development and landslide triggering. We perform a series of virtual experiments to address how subsurface topography affects the location and spatial pattern of slip surface development and pore pressure dynamics. We use a 3D DarcyRichards equation solver (Hydrus 3-D) combined with a cellular automata slope stability model to simulate the spatial propagation of the destabilized area. Our results showed that the soilbedrock interface and in particular, bedrock depressions, played a key role in pore pressure dynamics, acting as an impedance for the downslope drainage of perched water. Filling and spilling of depressions in the bedrock surface microtopography induced localized zones of increased pressure head such that the development of pore-pressure fieldsnot predictable by surface topographylead to rapid landslide propagation. Our work suggests that landslide models should consider the subsurface topography in order to include a connectivity component in the mathematical description of hydrological processes operating at the hillslope scale. Copyright (C) 2012 John Wiley & Sons, Ltd.
Larsen MC and Simon A (1993), "A Rainfall Intensity-Duration Threshold for Landslides in a Humid-Tropical Environment, Puerto Rico", Geografiska Annaler. Series A, Physical Geography. Vol. 75(1/2), pp. pp. 13-23. Wiley on behalf of the Swedish Society for Anthropology and Geography.
Abstract: Landslides are triggered by factors such as heavy rainfall, seismic activity, and construction on hill-slopes. The leading cause of landslides in Puerto Rico is intense and/or prolonged rainfall. A rainfall threshold for rainfall-triggered landsliding is delimited by 256 storms that occurred between 1959 and 1991 in the central mountains of Puerto Rico, where mean annual rainfall is close to or in excess of 2,000 mm. Forty one of the 256 storms produced intense and/or prolonged rainfall that resulted in tens to hundreds of landslides. A threshold fitted to the lower boundary of the field defined by landslide-triggering storms is expressed as I = 91.46 D-0.82 where I is rainfall intensity in millimeters per hour, and D is duration in hours. Landslide-producing storms occurred at an average rate of 1.2 per year. In general the landslides triggered by short-duration, high-intensity rainfall events were mainly shallow soil slips and debris flows, while the long-duration, low-intensity rainfall produced larger, deeper debris avalanches and slumps. For storms that had durations of up to 10 h, landsliding did not occur until rainfall intensity was as much as three times as high as the rainfall intensity reported as sufficient to trigger landsliding in temperate regions. As storm durations approach 100 h, the rainfall conditions necessary to initiate landsliding in Puerto Rico converge with those defined for temperate regions. A comparison of the Puerto Rico threshold with rainfall data from other humid-tropical regions suggests that the threshold developed for Puerto Rico may be applicable to other similar environments throughout the world.
Lateltin O (1997), "Berücksichtigung der Massenbewegungsgefahren bei raumwirksamen Tätigkeiten" Bern, Switzerland. BRP, BWW, BUWAL.
Abstract: Die neuen Bundesgesetze über den Wasserbau und den Wald verpflichten die Kantone, Gefahrenkarten zu erstellen und diese bei ihren raumwirksamen Tätigkeiten zu berücksichtigen. Die vorliegende Publikation gibt Empfehlungen für die Erfüllung dieser Aufgaben. Sie richtet sich deshalb sowohl an die Fachleute bei Bund, Kantonen und Gemeinden, die Massenbewegungsgefahren beurteilen und die für Schutzmassnahmen zuständig sind, als auch an die politischen Instanzen, welche Entscheide über raumwirksame Tätigkeiten treffen. Angesprochen sind zudem jene Grundeigentümer, die über die Gefährdung ihrer Grundstücke informiert sein sollen. Ausgearbeitet wurden diese Empfehlungen von einer interdisziplinären Arbeitsgruppe unter der Leitung der LHG (Landeshydrologie und -geologie). Der Arbeitsgruppe gehörten Fachleute aus dem Bundesamt für Umwelt, Wald und Landschaft (BUWAL, Eidg. Forstdirektion), dem Bundesamt für Wasserwirtschaft (BWW) und – neben anderen Fachstellen des Bundes – auch Vertreter der Kantone BE, FR, TI, VS sowie von Hochschulen und privaten Büros an.
Die Raumplanung benötigt für alle Naturgefahren gleichwertige Unterlagen. Die vorliegenden Empfehlungen lehnen sich daher inhaltlich an die «Richtlinien zur Berücksichtigung der Lawinengefahr bei raumwirksamen Tätigkeiten» (Bundesamt für Forstwesen, 1984) und die «Empfehlungen zur Berücksichtigung der Hochwassergefahren bei raumwirksamen Tätigkeiten» (BWW/BRP/BUWAL, 1997) an. Die vorliegenden Empfehlungen sind bei der Erstellung von Gefahrenkarten und bei deren Anwendung zu berücksichtigen.
Lateltin O, Haemmig C, Raetzo H and Bonnard C (2005), "Landslide risk management in Switzerland", Landslides., December, 2005. Vol. 2(4), pp. 313-320.
Abstract: Six percent of Switzerland is prone to slope instability. New federal regulations require regional authorities (cantons) to generate natural hazard maps and the zoning of mass movements in order to restrict development on hazard-prone land. The Codes of Practice for hazard maps use red, blue and yellow respectively, to indicate areas of prohibited construction, construction with safety requirements and construction without restriction. They need considerable efforts to ensure communication with local populations. The present state of landslide hazard mapping in the 26 cantons, the transcription of hazard maps to local management plans and the corresponding rules are presented.
Lateltin O, Raetzo H and Zanetta P (2004), "Recent catastrophic landslides in Switzerland", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 131-135. Taylor & Francis.
Abstract: Recent catastrophic landslides occurred in Switzerland during the years 1999, 2000 and 2002. The documentation of these events revealed different triggering factors related to heavy rain of short duration (local thunderstorms) or prolonged heavy precipitation period lasting up to several days over an extended area. Land-use planning and the resulting zoning laws are among the most effective tools to cope with these catastrophic events. Since 1991, the Swiss cantons are required to established hazards maps and zoning for landslides to restrict development in hazard-prone land. These hazard maps take into account potential landslides after long duration precipitation but show also limitation for events triggered by thunderstorms.
Lee D-H, Lai M-H, Wu J-H, Chi Y-Y, Ko W-T and Lee B-L (2013), "Slope management criteria for Alishan Highway based on database of heavy rainfall-induced slope failures", Engineering Geology . Vol. 162(0), pp. 97 - 107.
Abstract: Abstract In this paper, a study of slope failures along the Alishan Highway (locally, known as "Tai-18") is carried out. An innovative empirical model is developed based on 15-year records of typhoon rainfall-induced slope failures. This model is intended for assessing the likelihood of slope failure along Tai-18 in the future. The rainfall data considered in the proposed model include the maximum hourly rainfall and the effective cumulative rainfall. The effective cumulative rainfall is defined at the point when the curve of cumulative rainfall goes from steep to flat. Then, a simple criterion is established for assessing the potential of slope failure and issuing warning and/or closure for Tai-18 during a future extreme rainfall. Slope failures during Typhoon Saola in 2012 and those in Japan demonstrate that the new empirical model is effective and applicable to other regions with similar rainfall conditions.
Lee S and Min K (2001), "Statistical analysis of landslide susceptibility at Yongin, Korea", Environmental Geology. Vol. 40(9), pp. 1095-1113. Springer-Verlag.
Abstract: The aim of this study is to evaluate the susceptibility of landslides at Yongin, Korea, using a geographic information system (GIS). Landslide locations were identified in the Yongin area from interpretation of aerial photographs, field surveys, and maps of the topography, soil type, timber cover, and geology. These data were collected and constructed into a spatial database using GIS. The factors that influence landslide occurrence, such as slope, aspect, and curvature of topography, were calculated from the topographic database. Texture, material, drainage, and effective soil thickness were extracted from the soil database, and type, age, diameter, and density of timber were extracted from the forest database. Lithology was extracted from the geological database, and land use was classified from the Landsat TM satellite image. Landslide susceptibility was analyzed using the landslide occurrence factors by probability and logistic regression methods. The results of the analysis were verified using the landslide location data. The validation results showed satisfactory agreement between the susceptibility map and the existing data on landslide location. The GIS was used to analyze the vast amount of data efficiently, and statistical programs were used to maintain specificity and accuracy. The results can be used to reduce associated hazards, and to plan land use and construction.
Leitinger G, Hoeller P, Tasser E, Walde J and Tappeiner U (2008), "Development and validation of a spatial snow-glide model", Ecological Modelling., March, 2008. Vol. 211(3-4), pp. 363-374.
Abstract: Snow gliding is a key component leading to natural hazards, i.e. avalanches and erosions, and due to ongoing global changes has become a topic of major concern. Spatial information on snow gliding is important for management purposes, but, to date, lack of knowledge about key drivers for the snow-glide process hindered the development of a spatial snow-glide model (SSGM). We report the most important drivers for snow gliding derived from analyzing snow-glide distances taken over five winter periods in two climatically different study areas by ordinary least-squares regression. Six variables (forest stand, slope angle, winter precipitation, surface roughness, slope aspect west, slope aspect east) were revealed as key drivers and enabled us for the first time to establish a SSGM. Both model development (R(2)=0.838) and model validation (R(2)=0.823) exhibit outstanding accuracy of prediction. Hence, the SSGM was used to model snow-glide maps for both study areas: the 'Kaserstattalm' (Stubai Valley, North Tyrol, Austria) and the drier and warmer area of the 'Waltner Mahder' (Passeier Valley, South Tyrol, Italy). The reliability of these maps was validated by intersection with mapped erosions attributed to snow gliding. Therewith, such potential snow-glide maps have management relevance and are useful and necessary for risk assessment as well as to raise awareness about snow gliding to the land owners and regional managers. (c) 2007 Elsevier B.V. All rights reserved.
Leopold L, Emmett W and Myrick R (1966), "Channel and Hillslope Processes in a Semiarid Area New Mexico", United States Geological Survey Professional Paper. Vol. 352-G, pp. 193-252.
Abstract: Ephemeral washes having drainage areas from a few acres to 5 square miles are shown by actual measurement to be accumulating sediment on the streambed. This aggradation is not apparent to the eye but is clearly shown in 7 years of annual remeasurement.
A similar aggradation was in progress in the same area some 3000 years ago as evidenced by an alluvial terrace later dissected by the present channel system. At that time as well as at present. aggradation occurred even in tributary areas draining a few acres. Colluvial accumulations merge with channel deposits and blanket the valleys and tributary basins even up to a few hundred feet of the drainage divides. The present study concerned the amounts of sediment produced by different erosion processes in various physiographic positions in the drainage basins. Measurements show that by far the largest sediment source is sheet erosion operating on the small percentage of basin area near the basin divides.
Slope movement, gully head extension, and channel enlargement are presently small contributors of sediment compared wt'n sheet erosion on unrilled slopes. As in previous studies, not all of the erosion products could be accounted for by accumulations on colluvial slopes and on beds of channels. The discrepancies are attributed primarily to sediment carried completely out of the basins studied and presumably deposited somewhere downstream.
Aggradation of alluvial valleys of 5 square miles area and smaller both in the present epicycle. and in prehistorical but post-glacial times in this locality, cannot be attributed to gullying or rill extension in the headwater tributaries but to sheet erosion of the most upstream margins of the basins.
Studies of rainfall characteristics of the 7 years of measurement compared with previous years in the 100-year record do not provide a clear-out difference which would account for the presently observed aggradation of channels. Longer period of measurement of erosion and sedimentation will be necessary to identify what precipitation parameters govern whether the channels aggrade or degrade.
Leroueil S (2004), "Geotechnics of slopes before failure", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 2, pp. 863-884. Taylor & Francis.
Abstract: This paper examines the geotechnical phenomena that may occur in a slope before failure. The first part reviews the main mechanical processes that could lead to slope failures; approaches to investigate slopes in order to evidence pre-failure revealing factors are then described; and finally, the third part indicates how pre-failure processes can be considered in geotechnical engineering in order to decrease the probability of slope failures.
Li X, He HS, Wang X, Bu R, Hu Y and Chang Y (2004), "Evaluating the effectiveness of neutral landscape models to represent a real landscape ", Landscape and Urban Planning . Vol. 69(1), pp. 137 - 148.
Abstract: Neutral landscape models are often employed to represent real landscapes as the null hypothesis. They usually have statistical characteristics similar to real ones. But the spatial characteristics of the real and generated maps are seldom compared. In this study, the neutral landscape models generated by Rule and SimMap are tested against a real forest landscape in Northeastern China. A set of landscape metrics is used for the comparison. Values of some metrics (total number of patches, total perimeter, and aggregation index) suggest that some level of agreement between the maps generated by neutral landscape models and the real landscape do exist at landscape and class levels. But there are also metrics that do not show any agreement between generated maps and the real landscape. Neutral models tend to over-aggregate small classes at higher aggregation levels. Each neutral model has its own strength in representing the real landscape, though neither is perfect. Some metrics, for example, double-logged fractal dimension, are found to have limited capabilities in differentiating landscape structures.
Liener S and Kienholz H (2000), "Modellierung von flachgründigen Rutschungen mit dem Modell SLIDISP", In Proc. of the IX International Congress Interpraevent 2000, Villach. Villach , pp. 259-269.
Abstract: Das Modell SLIDISP basiert auf einer anerkannten Stabilitätsberechnungsmethode (Infinite-Slope-Analysis), die in ein Geographisches Informationssystem integriert wurde. Die wichtigsten rutschungsrelevanten Eigenschaften wie Hangneigung, Scherparameter, Lockermaterialmächtigkeit und Porenwasserdruck müssen flächendeckend erhoben werden, damit die als Parameter ins Modell eingegeben werden können. Mit probabilistischen Funktionen wird die natürliche Variabilität der Scherparameter und des Porenwasserdrucks simuliert und somit bei der Bestimmung der Rutschanfälligkeit berücksichtigt. Die erstellten Gefahrenhinweiskarten geben in einem mittleren Massstab Auskunft darüber, wo flachgründige Rutschungen im Lockermaterial mit grosser und mittlerer Wahrscheinlichkeit auftreten können.
Liener S, Liniger M, Krummenacher B and Kienholz H (1996), "Abgrenzung rutschgefährdeter Gebiete – Entwicklung eines Dispositionsmodells", In Proc. of the VIII International Congress Interpraevent 1996, Garmisch-Partenkirchen. Garmisch-Partenkirchen Vol. 3, pp. 151-160.
Abstract: Das Verfahren SLIDISP verwendet bekannte Stabilitätsberechnungsmethoden ('Janbu ' und 'Bishop') in Kombination mit einem Geographischen Informationssystem um eine Gefahrenhinweiskarte für Rutschungen zu erstellen. Für jede Substratklasse wird die kritische Hangneigung berechnet, welche potentielle Rutschgebiete von stabilen Gebieten abgrenzt. Die Verknüpfung der Substratkarte mit den vom digitalen Höhenmodell abgeleiteten Hangneigungen erlaubt die Ausscheidung von potentiellen Anrissgebieten von Rutschungen.
Liu JK and Shih PTY (2013), "Topographic Correction of Wind-Driven Rainfall for Landslide Analysis in Central Taiwan with Validation from Aerial and Satellite Optical Images", Remote Sensing. Vol. 5, pp. 2571-2589.
Abstract: Rainfall intensity plays an important role in landslide prediction especially in mountain areas. However, the rainfall intensity of a location is usually interpolated from rainfall recorded at nearby gauges without considering any possible effects of topographic slopes. In order to obtain reliable rainfall intensity for disaster mitigation, this study proposes a rainfall-vector projection method for topographic-corrected rainfall. The
topographic-corrected rainfall is derived from wind speed, terminal velocity of raindrops, and topographical factors from digital terrain model. In addition, scatter plot was used to present landslide distribution with two triggering factors and kernel density analysis is adopted to enhance the perception of the distribution. Numerical analysis is conducted for a historic event, typhoon Mindulle, which occurred in 2004, in a location in central Taiwan. The largest correction reaches 11%, which indicates that topographic correction is significant. The corrected rainfall distribution is then applied to the analysis of landslide triggering factors. The result with corrected rainfall distribution provides better agreement with the actual landslide occurrence than the result without correction.
Löhmannsröben R (2002), "Die Bedeutung des Bodens im Zusammenhang mit der hydrologischen Regionalisierung", Wiener Mitteilungen., In Niederschlag-Abfluss Modellierung - Simulation und Prognose. Vol. 164, pp. 201-213.
Abstract: Der Boden nimmt im hydrologischen Geschehen eine herausragende Bedeutung ein. Seine Eigenschaften wie Körnung, Struktur, Porenvolumen, Horizontabfolge, Profilmächtigkeit und Hydromorphie bestimmen, welche Anteile des Niederschlags infiltrieren, oberflächlich oder oberflächennah abfließen, gespeichert werden oder in die Tiefe versickern (Hartge, 1978; Herrmann, 1977). Zurecht wird diese oberste Schicht der Erdoberfläche daher auch als „Herzstück“ (Forster, 1994), „Schlüsselstelle“ (Gutknecht, 1996) oder „Schaltstelle“ (Kirnbauer und Steidl, 1995) für den Wasserhaushalt, bzw. das hydrologische Modell angesehen.
Löhmannsröben R (1992), "Die Bedeutung der Bodenkartierung für die Beurteilung morpho- und hydrodynamischer Prozesse in Wildbacheinzugsgebieten", In Proc. of the VIII International Congress Interpraevent 1992, Bern. Bern Vol. 6, pp. 237-250.
Abstract: Der vorliegende Bericht stellt die Bedeutung des Bodens und seiner Kartierung für die Analyse von Schadens - und Gefahrenursachen in Wildbacheinzugsgebieten sowie für die Planung von Schutzmaßnahmen auf der Basis von Gefah renplänen heraus. Im Anschluß an eine Darstellung über die bislang vernachlässigte Rolle der Bodenkartierung im Alpenraum werden Ergebnisse derzeitiger Kartierungen im bayerischen Alpenraum vorgestellt.
Diese Kartierungen legen starke anthropogene Bodenveränderungen offen, die durch Reduzierung insbesondere von Gröbstporenvolumina und Wasserleitfähigkeit sowie durch eine Zunahme hydromorpher Böden das Abfluß- und Abtragsgeschehen im Wildbacheinzugsgebiet negativ beeinflussen. Dies belegen Vergleiche zwischen ungestörten und unterschiedlich degradierten Profilen. Wie stark die Bodenverhältnisse in das Gefahrenpotential eines Wildbacheinzugsgebietes einfließen, veranschaulicht, darüberhinaus ein Vergleich einer Bodenkarte mit Gefährdungskarten zur Oberflächenabfluß- und Abtragsbereitschaft, wobei eine starke Flächenkongruenz zwischen hydromorphologisch negativ zu bewertenden Böden und mäßig bis stark gefährdeten Flächen deutlich wird (Testgebiet: Hirschbach, Allgäu / BRD).
Löhmannsröben R and Schauer T (1996), "Ableitung hydrologischer Eigenschaften zur Beurteilung des Abfluss- und Abtragsgeschehens aus boden- und vegetationskundlichen Kriterien", In Proc. of the VIII International Congress Interpraevent 1996, Garmisch-Partenkirchen. Garmisch-Partenkirchen Vol. 1, pp. 99-112.
Abstract: Phenomena of mass movements are influenced by factors of the site of phenomena as weil as by these parts cf the slope which adjoin them. This report especially describes the influence of hydrological factors of the adjoining slopes. The hydrological factors determine, whether precipitation gets to runoff or will be absorbed by the soil, where the water might be retended or infiltrates into deeper layers or flows off as interflow. First the method of derivation of these factors, basing on detailed maps of soil and vegetation and of irrigation tests, is described. The results are represented in a "map of hydrological features in torrent watersheds". Afterwards the analysis, concerning relations between hydrology and mass movements, is confirmed by special examples.
Lu N, Wayllace A and Oh S (2013), "Infiltration-induced seasonally reactivated instability of a highway embankment near the Eisenhower Tunnel, Colorado, USA ", Engineering Geology . Vol. 162(0), pp. 22 - 32.
Abstract: Infiltration-induced landslides are major natural hazards. When they occur along highways they can impede traffic, damage infrastructure, and threaten public safety. This paper presents a case study of an active landslide on an embankment of Interstate-70 west of the Eisenhower Tunnel in central Colorado, USA. Records indicate that the hillslope under I-70 has moved episodically over the previous 40 years. In the previous two decades the road surface has been displaced vertically by more than 60 cm. The objective of this work is to develop a conceptual model capable of quantifying the seasonally reactivated landslide movement at the site. Inclinometer data of subsurface deformation and geologic and hydrologic mapping are used to develop the conceptual model as well as to constrain a numerical model. A two-dimensional hydro-mechanical numerical model is used to test the conceptual model under three different infiltration rates during the period of snowmelt in the spring. The framework used in the numerical model accounts for the major physical processes driving instability of the slope: time-dependent variably saturated flow, the resultant changes in stress, and induced deformation. When the snowmelt water infiltrates into the slope, the soil water content and the water-table level vary accordingly. These time-dependent variations result in changes in soil matric suction, effective stress, and consequently change in slope stability. The model calculates pore-water pressures, suction stress, and the distribution of effective stress in the embankment slope at different times. Global factors of safety as a function of time are calculated along the predetermined sliding surface using effective stresses calculated with finite elements. The slope stability assessment quantitatively confirms the conceptual model and is consistent with the displacements monitored at the site during the years of 2007–2009. It is shown that annual snowmelt infiltration of 60–100&#xa0;cm of water can reduce the factor of safety by 6%, enough to sustain landslide movement for as long as 8&#xa0;months each year.
Lu P, Stumpf A, Kerle N and Casagli N (2011), "Object-Oriented Change Detection for Landslide Rapid Mapping", Ieee Geoscience and Remote Sensing Letters., July, 2011. Vol. 8(4), pp. 701-705.
Abstract: A complete multitemporal landslide inventory, ideally updated after each major event, is essential for quantitative landslide hazard assessment. However, traditional mapping methods, which rely on manual interpretation of aerial photographs and intensive field surveys, are time consuming and not efficient for generating such event-based inventories. In this letter, a semiautomatic approach based on object-oriented change detection for landslide rapid mapping and using very high resolution optical images is introduced. The usefulness of this methodology is demonstrated on the Messina landslide event in southern Italy that occurred on October 1, 2009. The algorithm was first developed in a training area of Altolia and subsequently tested without modifications in an independent area of Itala. Correctly detected were 198 newly triggered landslides, with user accuracies of 81.8% for the number of landslides and 75.9% for the extent of landslides. The principal novelties of this letter are as follows: 1) a fully automatic problem-specified multiscale optimization for image segmentation and 2) a multitemporal analysis at object level with several systemized spectral and textural measurements.
Luzi L and Pergalani F (1996), "Applications of statistical and GIS techniques to slope instability zonation (1:50.000 Fabriano geological map sheet)", Soil Dynamics and Earthquake Engineering. Vol. 15(2), pp. 83-94.
Abstract: The aim of this work is the evaluation of the vulnerability of landslides in static, pseudostatic and dynamic conditions, to produce slope instability maps. A deterministic approach, using a GLS, (ILWIS 1.4 - The Integrated Land and Water Information System User's Manual, Enschede, 1993, The Netherlands) is presented. The analysis in static and pseudostatic conditions, using the infinite slope analysis and the ordinary slice method, is carried out and the values of Fs (factor of safety) and Kc (coefficient of critical horizontal acceleration) are evaluated; the analysis in dynamic condition is performed, using Newmark's method, (Geotechnique, 1965, 23, 139-60), and the value of the final displacement during the application of an accelerogram is calculated. The applied methodologies and the results for the area corresponding to the NE sector of the 1:50.000 ''Fabriano'' (Marche Region, Italy) geological map sheet, are presented.
Maag S, Nösberger J and Lüschner A (2001), "Mögliche Folgen einer Bewirtschaftungsaufgabe von Wiesen und Weiden im Berggebiet. Ergebnisse des Komponentenprojektes D, Polyprojekt PRIMALP"
Abstract: Im Rahmen des Polyprojektes PRIMALP der ETH Zürich wird in verschiedenen Projekten untersucht wie eine nachhaltige land- und forstwirtschaftliche Nutzung des Schweizerischen Alpenraumes in Zukunft aussehen kann. Die vorliegende Arbeit stellt einen Teil eines Komponenten-Projektes dar und befasst sich mit einer möglichen Verbrachung im Alpenraum. Einerseits lassen Modellrechnungen des PRIMALP-Kemprojektes für verschiedene Szenarien vermuten, dass in Abhängigkeit der wirtschaftlichen und politischen Rahmenbedingungn die Verbrachung in Zukunft ein grosses Problem in den Schweizer Alpenregionen werden kann. Bereits heute besteht in den Alpengebieten die Tendenz, unter den herrschenden politischen und ökonomischen Rahmenbedingungen Flächen in ungünstiger Lage mit eher geringer Produktivität und schlechten Bewirtschaftungsmöglichkeiten brachfallen zu lassen oder nur noch sehr extensiv zu bewirtschaften. Andererseits wird v.a. auf den Talböden, im unteren Bereich der Berghänge und auf günstig gelegenen Flächen die Nutzung intensiviert (Bätzing, 1988). Mit dieser Arbeit sollen anhand einer Literaturrecherche einerseits die Auswirkungen und Probleme einer Verbrachung im Berggebiet im Hinblick auf die Nachhaltigkeit anhand von ökologischen und agronomischen Aspekten aufgezeigt werden. Andererseits sollen Minimalnutzungsmöglichkeiten diskutiert werden, welche aus Kostengtünden häufig Weideverfahren sind.
MacDonald D, Crabtree JR, Wiesinger G, Dax T, Stamou N, Fleury P, Lazpita JG and Gibon A (2000), "Agricultural abandonment in mountain areas of Europe: Environmental consequences and policy response", Journal of Environmental Management., May, 2000. Vol. 59(1), pp. 47-69.
Abstract: Agricultural abandonment reflects a post war trend in western Europe of rural depopulation to which isolated and poorer areas are most vulnerable. The commercialisation of agriculture, through technological developments, and the influence of Common Agricultural Policy have increased productivity and focused agricultural activity on more fertile and accessible land thus transforming traditional approaches to farming. In many areas this has lead to a decline in traditional labour intensive practices and marginal agricultural land is being abandoned. The problems that these trends create are particularly marked in mountain areas. The social and economic impacts of these changes have been well documented. However, the implications for environmental policy are less well recognised. This paper reviews the literature on abandonment and gives a comparative analysis of European mountain case studies to assess the environmental impacts of land abandonment and decline in traditional farming practices. It finds abandonment is widespread and that, while the influence of environmental changes is unpredictable due to environmental, agricultural and socio-economic contextual factors, abandonment generally has an undesirable effect on the environmental parameters examined. The application of agh-environment policy measures in relation to abandonment is discussed and suggestions for future policy are proposed. (C) 2000 Academic Press.
Machatschek M (2012), "Schwendung von Grün- und Grau-Erlenbeständen", Der Alm- und Bergbauer. Vol. 4, pp. 7-11.
Abstract: Die Art der Berglandwirtschaft übt einen großen Einfluss auf das Abflussverhalten des Wassers und somit auf die Bildung von Muren und der daraus resultierenden Naturgefahren in den Unterliegergemeinden aus. Überalterte Grün- und Grauerlenfluren verursachen durch ihre Anreichenmg des Bodens mit Stickstoff das Abrutschen von Steilhängen. Unsere Bauern wussten in Vorzeiten, dass aus diesem Grund Erlenbestände einer Schwendung zu unterziehen und in Weiden umzuwandeln sind. Dieser Beitrag ist Herrn Univ.-Prof. Dr. Herbert Aulitzky, emeritierter Professor für Wildbach- und Lawinenverbauung der Universität für Bodenkultur in Wien, zum 90-igsten Geburtstag gewidmet.
Machatschek M (2012), "Grundsätzliche Anmerkungen und Folgerungen zu den Alp-Entwicklungsprojekten der Agrargemeinschaft Rankweil im Laternser Tal, Land Vorarlberg"
Machatschek M (2007), "Wird das Wasser am Berg nicht bewirtschaftet,
so „wirtschaftet” es im Tal. Alm- und Bergwaldbewirtschaftung als Schutz (Teil 1)"
, Der Alm- und Bergbauer. Vol. 5, pp. 4-7.
Abstract: Aus den Beobachtungen der Natur können wesentliche Aussagen für die Wasserbewirtschaftung im Bergraum abgeleitet werden. Die Art der Almweidewirtschaft z. B. beeinflusst das Wasserverhalten auf den Almflächen, im speichernden Berg, im Tal und im weiter abgelegenen Tiefland. Eine nachhaltige Almwirtschaft dient demnach der Erhaltung guter Wasserqualität und der kontinuierlichen Wasserversorgung mit diesem lebensnotwendigen Elixier. Und je sorgsamer die Hochweiden bewirtschaftet werden, umso größer ist der Schutz vor auftretenden Naturgefahren (z. B. Hochwässer).
Machatschek M (2007), "Wird das Wasser am Berg nicht bewirtschaftet,
so „wirtschaftet” es im Tal. Alm- und Bergwaldbewirtschaftung als Schutz (Teil 2)"
, Der Alm- und Bergbauer. Vol. 6-7, pp. 5-9.
Abstract: Eine nachhaltige Alm- und Bergwaldbewirtschaftung ist die Voraussetzung für den Schutz des alpinen Raumes vor zerstörerischen Naturgefahren. Dabei muss der bedeutende volkswirtschaftliche Gewinn, der von der bäuerlichen Nutzung erbracht wird, in den Vordergrund gestellt werden. Die Bewirtschaftung der Bergregionen sichert nicht nur den gebirgigen Raum, sondern auch die unterhalb liegenden Täler und Ebenen mit ihrer kostenintensiven Infrastruktur. Zudem ist immer der lokale Standort für die Betrachtung ausschlaggebend.
Maclean IMD, Bennie JJ, Scott AJ and Wilson RJ (2012), "A high-resolution model of soil and surface water conditions", Ecological Modelling., July, 2012. Vol. 237, pp. 109-119.
Abstract: Soil moisture and surface water conditions are key determinants of plant community composition and ecosystem function, and predicting such conditions is an important step in understanding the ecological consequences of environmental change. Typically, hydrological models that use real landscape features do not simulate water conditions at the fine spatial and temporal scales that are meaningful to many plant species and ecological processes. We present a hydrological model that simulates daily soil moisture and surface water conditions at a spatial resolution of 1 m x 1 m. The model is applied to 16 km(2) of the Lizard Peninsula, UK. The model is kept computationally efficient by combining a simple lumped parameter basin approach with the distributed hydrological effects of basin topography. We also model the complex flows occurring between small basins. Code for running the model using R statistical software is provided as supplementary material. As inputs, the model uses widely available daily weather variables, 1 m x 1 m resolution digital elevation data (LiDAR) and some simple vegetation and soil characteristics identifiable from aerial photographs. Our results indicate that when inter-basin water exchanges and the distributed effects of topography within each basin are not accounted for, the model performs less well than just assuming average conditions in time or space. However, modelling inter-basin water flow also substantially increases computer run-time. The full model is capable of correctly simulating a broad range of hydrological and soil moisture conditions, providing accurate predictions for areas that range from permanently wet through to permanently dry, as well as for ephemeral wetlands with highly variable water levels. We discuss some potential ecological applications of the model, for example in guiding conservation management. (C) 2012 Elsevier B.V. All rights reserved.
MacMillan RA, Pettapiece WW, Nolan SC and Goddard TW (2000), "A generic procedure for automatically segmenting landforms into landform elements using DEMs, heuristic rules and fuzzy logic", Fuzzy Sets and Systems., July, 2000. Vol. 113(1), pp. 81-109. Elsevier Science Bv.
Abstract: A robust new approach for describing and segmenting landforms which is directly applicable to precision farming has been developed in Alberta. The model uses derivatives computed from DEMs and a fuzzy rule base to identify up to 15 morphologically defined landform facets. The procedure adds several measures of relative landform position to the previous classification of Pennock et al. (Geoderma 40 (1987) 297-315; 64 (1994) 1-19). The original 15 facets can be grouped to reflect differences in complexity of the area or scale of application. Research testing suggests that a consolidation from 15 to 3 or 4 units provides practical, relevant separations at a farm field scale. These units are related to movement and accumulation of water in the landscape and are significantly different in terms of soil characteristics and crop yields. The units provide a base for benchmark soil testing, for applying biological models and for developing agronomic prescriptions and management options. Crown Copyright (C) 2000 Published by Elsevier Science B.V. All rights reserved.
Mader M (1999), "Auswirkungen unterschiedlicher Bewirtschaftung auf die Verteilung der Bodentypen und Auflagehumusformen sowie die Erosionsanfälligkeit (Kaserstattalm / Neustift im Stubaital)". Thesis at: University of Innsbruck, Institute of Botany.
Abstract: Im Zuge der Untersuchungen wurden eine Boden- und eine Auflagehumuskarte sowie detaillierte bodenkundliche Beschreibungen erstellt. Darüber hinaus wurde die Auflagehumusmasse, der pH-Wert, der C- und N-Gehalt sowie das C/N-Verhältnis bestimmt. Die Ergebnisse wurden unter Berücksichtigung des Ausgangsgesteins in drei Bewirtschaftungsreihen und einer Entwicklungsreihe miteinander verglichen. Bewirtschaftungsreihe 1 über Karbonat umfaßte dabei Rendzinen einer Weide und einer Brache. In Bewirtschaftungsreihe 2 über Silikat wurden Braunerden einer Weide, einer Brache und eines subalpinen Fichtenwalds miteinander verglichen. Bewirtschaftungsreihe 3 beschäftigte sich mit Braunerden einer intensiven Mähwiese, vermindert genutzten Mähwiesen, Brachen und einem subalpinen Fichtenwald über vorwiegend silikatischem Ausgangsgestein. In der Bodenentwicklungsreihe über Silikatgestein wurden einander Ranker, Braunerden, podsolierte Braunerden und Eisenhumuspodsole gegenübergestellt. Zur Analyse der Erosion wurden Erosionsaufnahmen durchgeführt und statistisch ausgewertet.
Malamud BD, Turcotte DL, Guzzetti F and Reichenbach P (2004), "Landslide inventories and their statistical properties", Earth Surface Processes and Landforms., June, 2004. Vol. 29(6), pp. 687-711.
Abstract: Landslides are generally associated with a trigger, such as an earthquake, a rapid snowmelt or a large storm. The landslide event can include a single landslide or many thousands. The frequency-area (or volume) distribution of a landslide event quantifies the number of landslides that occur at different sizes. We examine three well-documented landslide events, from Italy, Guatemala and the USA, each with a different triggering mechanism, and find that the landslide areas for all three are well approximated by the same three-parameter inverse-gamma distribution. For small landslide areas this distribution has an exponential 'roll-over' and for medium and large landslide areas decays as a power-law with exponent -2-40. One implication of this landslide distribution is that the mean area of landslides in the distribution is independent of the size of the event. We also introduce a landslide-event magnitude scale m(L) = log(N-LT), with N-LT the total number of landslides associated with a trigger. If a landslide-event inventory is incomplete (i.e. smaller landslides are not included), the partial inventory can be compared with our landslide probability distribution, and the corresponding landslide-event magnitude inferred. This technique can be applied to inventories of historical landslides, inferring the total number of landslides that occurred over geologic time, and how many of these have been erased by erosion, vegetation, and human activity. We have also considered three rockfall-dominated inventories, and find that the frequency-size distributions differ substantially from those associated with other landslide types. We suggest that our proposed frequency-size distribution for landslides (excluding rockfalls) will be useful in quantifying the severity of landslide events and the contribution of landslides to erosion. Copyright (C) 2004 John Wiley Sons, Ltd.
Malet JP, Maquaire O, Locat J and Remaitre A (2004), "Assessing debris flow hazards associated with slow moving landslides: methodology and numerical analyses", Landslides., March, 2004. Vol. 1(1), pp. 83-90.
Abstract: Clayey slow-moving landslides are characterized by their capability to suddenly change behaviour and release debris-flows. Due to their sediment volume and their high mobility, they are far more dangerous than those resulting from continuous erosive processes and associated potential high hazard magnitude on alluvial fans. A case of transformation from earthflow to debris-flow is presented. An approach combining geomorphology, geotechnics, rheology and numerical analysis is adopted. Results show a very good agreement between the yield stress values measured by laboratory tests, in the field according to the morphology of the levees, and by back-analyses using the debris-flow modelling code, Bing. The runout distances and the deposit thickness in the depositional area are also well reproduced. This allows proposing debris-flow risk scenarios. Results show that clayey earthflows can transform under 5-years return period rainfall conditions into 1 km runout debris-flows of volumes ranging between 2,000 to 5,000 m(3).
Malet J, Durand Y, Remaitre A, Maquaire O, Etchevers P, Guyomarch G, Deque M and van Beek L (2007), "Assessing the influence of climate change on the activity of landslides in the Ubaye Valley", In Proceedings International Conference on Landslides and Climate change-Challenges and Solutions. Ventnor, Isle of Wight, UK, May 2007, 2007. Wiley, London.
Abstract: Effects of past, present and future climate characteristics on landslide activity can be assessed by historical information, geomorphological evidences, and modelling of slope hydrology and mechanics. However there are a series of problems related to that approach. First, quantitative assessments of the spatial and temporal relationships between climate and landslide occurrences are often hampered by the inaccuracy and uncertainty of the historical records, and by the scarcity of climate data in mountain areas. Second, the climate-landslide coupling is complex, because climate is related to landslides via the nonlinear soil water system. Process-based models have been proposed to understand this complex interaction. However, landslide triggering systems show complex responses in relation to geotechnical, hydrological, and climate properties. Third, the uncertainty in future climate parameters is high, especially if the time context is greater than weather records or because of the low-resolution of the downscaled climate time series. The objectives of this paper is to present some results on the climate-landslide relationships for two landslide types observed in the Ubaye Valley, and to propose a method for assessing the impacts of climate change on landslide frequency.
Malet JP, van Asch TWJ, van Beek R and Maquaire O (2005), "Forecasting the behaviour of complex landslides with a spatially distributed hydrological model", Natural Hazards and Earth System Sciences. Vol. 5(1), pp. 71-85.
Abstract: The relationships between rainfall, hydrology and landslide movement are often difficult to establish. In this context, ground-water flow analyses and dynamic modelling can help to clarify these complex relations, simulate the landslide hydrological behaviour in real or hypothetical situations, and help to forecast future scenarios based on environmental change. The primary objective of this study is to investigate the possibility of including more temporal and spatial information in landslide hydrology forecasting, by using a physically based spatially distributed model. Results of the hydrological and geomorphological investigation of the Super-Sauze earthflow, one of the persistently active landslide occurring in clay-rich material of the French Alps, are presented. Field surveys, continuous monitoring and interpretation of the data have shown that, in such material, the groundwater level fluctuates on a seasonal time scale, with a strong influence of the unsaturated zone. Therefore a coupled unsaturated/saturated model, incorporating Darcian saturated flow, fissure flow and meltwater flow is needed to adequately represent the landslide hydrology. The conceptual model is implemented in a 2.5-D spatially distributed hydrological model. The model is calibrated and validated on a multi-parameters database acquired on the site since 1997. The complex time-dependent and three-dimensional groundwater regime is well described, in both the short- and long-term. The hydrological model is used to forecast the future hydrological behaviour of the earthflow in response to potential environmental changes.
Malet JP, Laigle D, Remaitre A and Maquaire O (2005), "Triggering conditions and mobility of debris flows associated to complex earthflows", Geomorphology., March, 2005. Vol. 66(1-4), pp. Int Assoc Geomophologists.
Abstract: Landslides on black marl slopes of the French Alps are, in most cases, complex catastrophic failures in which the initial structural slides transform into slow-moving earthflows. Under specific hydrological conditions, these earthflows can transform into debris flows. Due to their sediment volume and their high mobility, debris flow induced by landslides are far much dangerous than these resulting from continuous erosive processes. A fundamental point to correctly delineate the area exposed to debris flows on the alluvial fans is therefore to understand why and how some earthflows transform into debris flow while most of them stabilize. In this paper, a case of transformation from earthflow to debris flow is presented and analysed. An approach combining geomorphology, hydrology, geotechnics and rheology is adopted to model the debris flow initiation (failure stage) and its runout (postfailure stage). Using the Super-Sauze earthflow (Alpes-de-Haute-Provence, France) as a case study, the objective is to characterize the hydrological and mechanical conditions leading to debris flow initiation in such cohesive material. Results show a very good agreement between the observed runout distances and these calculated using the debris flow modeling code Cemagref 1-D. The deposit thickness in the depositional area and the velocities of the debris flows are also well reproduced. Furthermore, a dynamic slope stability analysis shows that conditions in the debris source area under average pore water pressures and moisture contents are close to failure. A small excess of water can therefore initiate failure. Seepage analysis is used to estimate the volume of debris that can be released for several hydroclimatic conditions. The failed volumes are then introduced in the Cemagref I-D runout code to propose debris flow hazard scenarios. Results show that clayey earthflow can transform under 5-year return period rainfall conditions into 1-km runout debris flow of volumes ranging between 2000 to 5000 m (3). Slope failures induced by 25-year return period rainfall can trigger large debris flow events (30,000 to 50,000 m 3) that can reach the alluvial fan and cause damage. (c) 2004 Elsevier B.V. All rights reserved.
Malet JP, Maquaire O and Calais E (2002), "The use of Global Positioning System techniques for the continuous monitoring of landslides: application to the Super-Sauze earthflow (Alpes-de-Haute-Provence, France)", Geomorphology., February, 2002. Vol. 43(1-2), pp. 33-54.
Abstract: Recent researches have demonstrated the applicability of using Global Positioning System (GPS) techniques to precisely determine the 3-D coordinates of moving points in the field of natural hazards. Indeed, the detailed analysis of the motion of a landslide, in particular for a near real-time warning system, requires the combination of accurate positioning in three dimensions (infracentimetric) and Fine temporal resolution (hourly or less). The monitoring of landslides with the GPS is usually performed using repeated campaigns, as a complement to conventional geodetic methods. Continuous monitoring of landslides with GPS is usually not performed operationally, mostly because of the cost of such a system compared to conventional deformation monitoring techniques. In addition, if GPS measurements can reach a millimetre-level accuracy for long observation sessions (typically 24 h), their accuracy decreases with the duration of the observation sessions, because of errors introduced by variations of the satellite constellation and multipath effects at the sites. This study aims at determining the experimental accuracy of GPS measurements for the continuous monitoring of landslides with GPS. In particular, we want to calibrate the variation of the measurement accuracy as a function of the duration of the observation sessions. The study was carried out on the Super-Sauze earthflow (Southern Alps, France) which evolves in a channelized flow with surface displacements reaching a few tens of centimetres to a few metres per year. The GPS data were acquired during two campaigns in May and October 1999 (two reference stations were installed outside the flow and four "moving" stations distributed on the flow). The maximal 3-D cumulative displacement reaches 2.1 m during 3 weeks in May 1999. The accuracy for a 1-h session reaches 2.7, 2.2 and 5.0 mm for the north-south, east-west and vertical components, respectively. The detectability threshold for a significant motion and a given temporal resolution stands between 3.5 mm/24 h and 8.5 mm/h in planimetry, between 6 mm/24 h and 19.5 mm/h in altimetry. Thus, the motion of the flow is clearly detected by the GPS measurements and the results have been compared with those obtained with conventional geodetic methods (theodolite and electronic distance-meters) or with a wire extensometer device. In addition, combination of periodical topometric measurements, continuous extensometric and GPS measurements allows us to identify seasonal and episodic transient variations in the surficial velocity of the flow. The analysis of the relationships between rainfall (and snowfall), groundwater level, and displacements permits us to understand the behaviour of the flow and to determine pore water pressures (PWP) thresholds initiating an acceleration of the movement. GPS therefore appears applicable to the continuous monitoring of geophysical objects or of man-made structures with small and slow displacements (similar to5 mm/day). This technique does not require direct line of sight between the "moving" sites and the reference stations. Measurements can be carried out in all weather and at night. GPS processing can be performed in near real time without loss of accuracy. The use of GPS is, however, limited by the environmental characteristics of the geophysical object (mountains, vegetation), which can constitute masks limiting the visibility of the sky and create multipaths effects. (C) 2002 Elsevier Science B.V. All rights reserved.
Mantovani F, Javier Gracia F, de Cosmo PD and Suma A (2010), "A new approach to landslide geomorphological mapping using the Open Source software in the Olvera area (Cadiz, Spain)", Landslides., March, 2010. Vol. 7(1), pp. 69-74.
Abstract: This paper presents the preliminary results of a geomorphological survey of the Olvera area (Cadiz province, Betic Ranges, Spain) and the use of the Geographic Information System (GIS) Open Source (OS) software plus Database Management System (DBMS) for making available and distributing the landslide data over the Web. In the geomorphologic survey, different landforms have been identified in the area, including structural, anthropogenic, fluvial, karst, and slope forms. In particular, the majority of the slope forms are complex (from topple to rotational slides and falls), but there are also minor forms like debris flows and mudslides. To manage geomorphological data, an Open Source GIS was used, which contained the following components: QuantumGIS, System for Automated Geoscientific Analyses (SAGA), GIS and Geographic Resources Analysis Support System (GRASS), GIS for Digital Elevation Model (DEM) generation. A key aim was to make the project-derived data available over the Web. This was achieved using MapServer which allows for the representation of the derived geospatial data with pMapper providing the graphical Web interface. Our study highlights the process dynamics of run-off erosion in Olvera derived through the use of advanced computer-based mapping tools. The resulting map products and interpretations are available via the Internet. To date, derivative maps have been produced to improve maintenance of roads and transport and of the construction of new infrastructure.
Mantovani F, Soeters R and VanWesten CJ (1996), "Remote sensing techniques for landslide studies and hazard zonation in Europe", Geomorphology., April, 1996. Vol. 15(3-4), pp. Int Assoc Geomorphologists.
Abstract: An inventory is presented of researches concerning the use of remote sensing for landslide studies and hazard zonation as mainly carried out in the countries belonging to the European Community. An overview is given of the applicability of remote sensing in the following phases of landslide studies: (1) Detection and classification of landslides. Special emphasis is given to the types of imagery required at different scales of analysis. (2) Monitoring the activity of existing landslides using G.P.S., photogrammetrical techniques and radar interferometry. (3) Analysis and prediction in space and time of slope failures. The different factors required in a landslide hazard study are evaluated, and the optimum remote sensing imagery for obtaining each of these factors is indicated. Examples are given of research work carried out in these three phases from EC countries. Finally an evaluation is given of the aspects of uncertainty associated with the use of remote sensing data, and conclusions are given as to the incorporation of remote sensing techniques within the overall framework of techniques.
Mantovani M, Marcato G, Silvano S, Zannoni A, Pasuto A and Tagliavini F (2004), "Slope instability around the Sauris reservoir (North-eastern Italy)", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 79-84. Taylor & Francis.
Abstract: The Sauris Lake is a hydroelectric basin closed by a double arc dam. The presence of Lower Trias clayey formations makes the whole catchment prone to landslide and, thus, also to situations of high risk. A landsliding event which has continued since October 2002 ("La Maina" landslide) has caused the opening of several fractures and mobilised a volume of about 1,500,000 m3. A monitoring system has been setup to control surface and deep displacements, and to follow the evolution of the instability in relation to the lake at the foot of the landslide. In response to a request from the Regional Authority for Civil Protection, a new landslide hazard map has been prepared for La Maina and the surrounding basin. Analysis of multitemporal aerial photos has revealed that several localised instabilities occur throughout the zone and present a threat to road infrastructures and the underlying lake.
Markart G, Kohl B and Perzl F (2007), "Der Bergwald und seine hydrologische Wirkung – eine unterschätzte Größe?", LWF Wissen. Vol. 55, pp. 34-43.
Abstract: In Zeiten einer Häufung von Schadereignissen durch Hochwasser, Muren und Rutschungen wird zwangsläufig die Frage nach der Effizienz der bisherigen technischen Maßnahmen, flächen wirtschaftlicher Eingriffe und der Bewirtschaftung der Oberfläche von solchen Ereignissen betroffener Gebiete gestellt. Eine gute Waldausstattung in alpinen Einzugsgebieten wurde früher als Versicherung gegen Naturgefahren angesehen. In den letzten Jahren wird jedoch die Wirkung der Waldvegetation als Schutz vor Naturgefahren immer stärker hinterfragt.
Im folgenden wird die hydrologische Wirkung der Waldvegetation in alpinen Einzugsgebieten kurz diskutiert. Die Autoren zeichnen ein überwiegend positives Bild der Waldwirkung. Es beruht auf den Ergebnissen von hydrologischen Untersuchungen und Analysen von Schadereignissen in einer Vielzahl von Wildbacheinzugsgebieten des Ostalpenraumes. In einer Reihe in den letzten Jahren erschienener Arbeiten wird die hydrologische Wirkung der Waldvegetation insbesondere bei Niederschlägen langer Dauer kritisch hinterfragt. "Bei gleichen Niederschfagverhältnissen kann somit der Hilld, je nach Bodenbedingungen, eine Schutzwirkung haben oder nicht formulieren HEGG el al. (2004). BURCH et al. (1996) stellten im Zuge ihrer Analysen von drei Einzugsgebieten keinen statistisch signifikanten Zusammenhang zwischen Bewaldungsgrad und Hochwasserabflussspitzen fest. COSANDEY et al. (2005) erhielten bei der Auswertung mehrerer forsthydrologischer Studien in Südfrankreich deutlich divergierende Ergebnisse, von hoher Waldwirkung bis zu keinem Unterschied zwischen Wald und Grasland in der Abflussbildung.
Im folgenden zeichnen die Autoren dennoch ein überwiegend positives Bild der Waldwirkung. Es beruht auf den Ergebnissen oon Untersuchungen und Analysen von Schadereignissen in einer Vielzahl von Wildbacheinzugsgebieten des Ostalpenraumes.
Markart G, Kohl B, Sotier B, Schauer B, Bunza G and Stern R (2004), "Provisorische Geländeanleitung zur Anschätzung des Oberflächenabflusses auf alpinen Boden-/Vegetationseinheiten bei konvektiven Starkregen (Version 1.0)", In BFW-Dokumentation. Wien Vol. 3, pp. 88. Schriftenreihe des Bundesamtes und Forschungszentrums für Wald.
Abstract: Seit annähernd 3 Jahrzehnten werden am Institut für Lawinen- und Wildbachforschung beim Bundesamt und Forschungszentrum für Wald (Innsbruck und Wien) und am Bayerischen Landesamt für Wasserwirtschaft in München Starkregensimulationen und begleitende Untersuchungen, wie Erhebungen boden- und vegetationskundlicher Kennwerte zur Charakterisierung des Abflussverhaltens beitragender Flächen in Wildbacheinzugsgebieten durchgeführt. Die Ergebnisse von mittlerweile über 700 Einzelberegnungen wurden in einer gemeinsamen Datenbank zusammengeführt und ausgewertet.
Ein erstes Produkt dieser Auswertungen ist die vorliegende Geländeanleitung zur Abschätzung des Oberflächenabflussbeiwertes bei konvektiven Starkregen. Sie ist die Basis für die Erstellung von Abflussbeiwertkarten zur Berechnung von Abflussspitze und Abflussfracht beim Bemessungsereignis in Wildbacheinzugsgebieten. Die gegenständliche Anleitung enthält Hinweise für die quantitative und qualitative Abschätzung des Oberflächenabflussbeiwertes bei Abflusskonstanz, einen Ansatz zur Anschätzung der Rauhigkeit der Oberfläche und eine Funktion zur Abschätzung der Initialabstraktion auf beitragenden Flächen in Wildbacheinzugsgebieten.
Markart G, Kohl B, Sotier B, Schauer T, Bunza G and Stern R (2006), "Geländeanleitung zur Abschätzung des Oberflächenabflussbeiwertes bei Starkregen - Grundzüge und erste Erfahrungen.", In Geländeanleitung zur Abschätzung des Oberflächenabflussbeiwertes bei Starkregen - Grundzüge und erste Erfahrungen. ÖWAV-Seminar „Methoden der hydrologischen Regionalisierung“ im Lebensministerium, 18.-19.5.2006, Wiener Mitteilungen 197, 159 – 178..
Markart G, Perzl F, Kohl B, Luzian R, Kleemayr K, Ess B and Mayerl J (2007), "Schadereignisse 22./23. August 2005 - Ereignisdokumentation und -analyse in ausgewählten Gemeinden Vorarlbergs", In BFW-Dokumentation. Vol. 5 Bundesforschungs-und Aubildungszentrum für Wald, Naturgefahren und Landschaft.
Martelloni G, Segoni S, Fanti R and Catani F (2012), "Rainfall thresholds for the forecasting of landslide occurrence at regional scale", Landslides., December, 2012. Vol. 9(4), pp. 485-495.
Abstract: This paper concerns a regional scale warning system for landslides that relies on a decisional algorithm based on the comparison between rainfall recordings and statistically defined thresholds. The latter were based on the total amount of rainfall, which was cumulated considering different time intervals: 1-, 2- and 3-day cumulates took into account the critical rainfall influencing shallow movements, whilst a variable time interval cumulate (up to 240 days) was used to consider the triggering of deep-seated landslides in low permeability terrains. A prototypal version of the model was initially set up to define statistical thresholds. Then, thresholds were calibrated using a database of past georegistered and dated landslides. A validation procedure showed that the calibration highly improves the results and therefore the model was integrated in the regional warning system of Emilia Romagna (Italy) for civil protection purposes. The proposed methodology could be easily implemented in other similar regions and countries where a sufficiently organised meteorological network is present.
Martha TR, Kerle N, Jetten V, van Westen CJ and Kumar KV (2010), "Characterising spectral, spatial and morphometric properties of landslides for semi-automatic detection using object-oriented methods", Geomorphology., March, 2010. Vol. 116(1-2), pp. 24-36.
Abstract: Recognition and classification of landslides is a critical requirement in pre- and post-disaster hazard analysis. This has been primarily done through field mapping or manual image interpretation. However, image interpretation can also be done semi-automatically by creating a routine in object-based classification using the spectral, spatial and morphometric properties of landslides, and by incorporating expert knowledge. This is a difficult task since a fresh landslide has spectral properties that are nearly identical to those of other natural objects, such as river sand and rocky outcrops, and they also do not have unique shapes. This paper investigates the use of a combination of spectral, shape and contextual information to detect landslides. The algorithm is tested with a 5.8 m multispectral data from Resourcesat-1 and a 10 m digital terrain model generated from 2.5 m Cartosat-1 imagery for an area in the rugged Himalayas in India. It uses objects derived from the segmentation of a multispectral image as classifying units for object-oriented analysis. Spectral information together with shape and morphometric characteristics was used initially to separate landslides from false positives. Objects recognised as landslides were subsequently classified based on material type and movement as debris slides, debris flows and rock slides, using adjacency and morphometric criteria. They were further classified for their failure mechanism using terrain curvature. The procedure was developed for a training catchment and then applied without further modification on an independent catchment. A total of five landslide types were detected by this method with 76.4% recognition and 69.1% classification accuracies. This method detects landslides relatively quickly, and hence has the potential to aid risk analysis, disaster management and decision making processes in the aftermath of an earthquake or an extreme rainfall event. (C) 2009 Elsevier B.V. All rights reserved.
Marui H (1984), "Die Mechanik oberflächennaher Bewegungen", In Proc. of the V International Congress Interpraevent 1984, Villach. Villach Vol. 3, pp. 141-156.
Abstract: Auf der Grundlage der Bodenmechanik soll in der folgen den Abhandlung die Mechanik oberflächennaher Bewegungen im Falle von Starkniederschlägen dargelegt und begründet werden. Die oberflächennahen Bewegungen haben besondere Bedeutung wegen ihrer großen Häufigkeiten und daher unterliegen sie der Erosions-Kontrolle . An Böschungen in verwitterten Granitgebirgen ereignen sich oft oberflächennahe Bewegungen. An solchen Böschungen habe ich daher die verschiedenen Eigenschaften des oberflächenndhen Bodens, d. h. Scherfestigkeit, Bodendichte, Bodenfeuchtigkeit, und Saugvermögen usw. gemessen und untersucht. Für die Erklärung der Mechanik oberflächennaher Bewegungen ist es notwendig, die Scherfestigkeit zu messen. Es war bisher schwierig, sie am oberflächennahen Boden zu messen, weil er unter niedriger Spannung steht. Mit dem neu entwickelten "Felddirektschergerät" kann sie aber im oberflächennahen Boden richtig gemessen werden. Die Meßergebnisse zeigten, daß die Scherfestigkeit bzw. der Winkel des Scherwiderstandes und die scheinbare Kohäsion je nach Tiefe unterschiedlich sind. Es wird erkennbar, daß man die unterschiedlichen Winkel des Scherwiderstandes und die scheinbare Kohäsion für die Standsicherheitsberechnung von Böschungen benutzen muß. Außerdem ist es wichtig, die Veränderung der Scherfestigkeit des Bodens, die durch Veränderung des Bodenzustandes von ungesättigt zu gesättigt verursacht wird, zu messen bzw. zu untersuchen. Daher werden die Scherfestigkeit und das Saugvermögen des Bodens für jeweils beide Zustände (gesättgt und ungesättigt) gemessen. Dabei zeigt es sieh, daß in Anwendung der Theorie von Bishop über "Wirksame Spannung für ungesättigte Böden" der Unterschied der Scherfestigkeit des Bodens zwischen gesättigtem und ungesättigtem Zustand durch die Wirkung des Saugvermögens verursacht wird. Es soll im folgenden erklärt werden, daß für das Phänomen ober flächennaher Bewegung nicht nur die Wirkung des Porenwasserdrucks und die Zunahme des Bodengewichts, sondern auch die durch den Verlust des Saugvermogens verursachte Abnahme der Scherfestigkeit eine entscheidende Rolle spielt.
Matsushi Y, Hattanji T and Matsukura Y (2006), "Mechanisms of shallow landslides on soil-mantled hillslopes with permeable and impermeable bedrocks in the Boso Peninsula, Japan", Geomorphology., June, 2006. Vol. 76(1-2), pp. 92-108. Elsevier Science Bv.
Abstract: Rainfall-induced shallow landslides play a vital role in hillslope denudation processes in humid temperate regions. This study demonstrates the contrasting mechanisms of landslides in adjoining hills with permeable (sandstone) and impermeable (mudstone) bedrock in the Boso Peninsula, Japan. The characteristics of slope hydrology were inferred from pressure-head monitoring and rainfall-runoff observations. An analysis of slope stability provided critical conditions for several previously occurring landslides. The results are as follows. (1) In slopes with the permeable sandstone, infiltrated rainwater percolates through the bedrock as an unsaturated gravitational flow. The wetting front migration results in a decrease of soil cohesion and causes landsliding at the steep lower part of the hillslopes. (2) In contrast, the impermeable mudstone beneath a thin soil layer causes a transient positive pressure head that generates a saturated subsurface storm flow. The reduction in effective normal stress triggers shallow soil slipping at the uppermost part of a hollow. (c) 2005 Elsevier B.V. All rights reserved.
Maynard T, Smith N and Vincenti A (2011), "Landslide risk and climate change in the european alps"
Abstract: The risk of landslides in the European Alps is considerable and has important implications for the insurance industry given the high levels of tourism and leisure based development in the region. Understanding how this risk may change in the future and in particular the influence of a changing climate on the magnitude and frequency of damaging landslides will be of value to insurers. This is why Lloyd’s chose to fund this research into landslide probability and climate change in the European Alps.
This research is being undertaken by Joanne Wood at the University of Exeter. Joanne has a degree in Geography from the University of Sheffield. As part of this degree, she took a module on geophysical hazards which looked at landslides and mass movements. Her undergraduate dissertation focused on glacier fluctuations and reconstruction of past glacial movements in the Bernese Alps, Switzerland. Joanne obtained a masters degree in Climate Change and Risk Management at the University of Exeter in 2008 before undertaking her current PhD research looking at the influence of climate change on mass movements in the European Alps. The following paper outlines the scope of this research and the main objectives and potential outcomes. The findings of this research will be presented in a later paper.
McDougall S and Hungr O (2004), "A universal model for 3-D runout analysis of landslides", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 2, pp. 1485-1488. Taylor & Francis.
Abstract: A new continuum model for the simulation of the flow of rapid landslides over 3-D terrain has been developed. Based on the St. Venant equations and Smoothed Particle Hydrodynamics, the model incorporates the following features, required specifically for modeling of various types of mobile landslides: I) non-hydrostatic internal stress distribution, as appropriate for internal flow deformation of a frictional material, 2) an open rheological kernel, allowing the simulation of flow of a variety of geological materials, 3) the ability to entrain material from the flow path and 4) a flexible, meshless solution method, suitable for complex 3-D path geometry. With these features, the new model provides a realistic and flexible framework for analysis of landslide runout.
McHugh M, Harrod T and Morgan R (2002), "The extent of soil erosion in upland England and Wales", Earth Surface Processes and Landforms., January, 2002. Vol. 27(1), pp. 99-107.
Abstract: Following recommendations by the 19th Royal Commission on Environmental Pollution, the area, causes and rates of upland soil erosion in England and Wales were investigated between 1997 and 1999. This paper describes the methods and results of the field survey of 1999 in which the extent of eroded around was determined. The area of degraded soil and the volume of eroded material were both determined from the dimensions of individual erosion features at 399 field sites located on an orthogonal grid across the uplands. Using measurements of individual erosion features, degraded soil extent in upland England and Wales was estimated at almost 25 000 ha, 2.46 per cent of the total upland area surveyed. Half this eroded area was revegetated and no longer subject to continued accelerated soil loss in 1999. The total volume of eroded material was estimated at 0.284 km(3). Although deposition of eroded material occurred within 20 per cent of eroded field sites, the total volume of redeposited material was less than 1 per cent of the total volume of eroded soil. Erosion was more extensive on peat soils than on dry, wet mineral or wet peaty mineral soils. In addition, the higher incidence of erosion at high altitudes and on low slopes reinforced the relationship between erosion and areas of peat formation. Copyright (C) 2002 John Wiley Sons, Ltd.
McKean J and Roering J (2004), "Objective landslide detection and surface morphology mapping using high-resolution airborne laser altimetry", Geomorphology., February, 2004. Vol. 57(3-4), pp. 331-351.
Abstract: A map of extant slope failures is the most basic element of any landslide assessment. Without an accurate inventory of slope instability, it is not possible to analyze the controls on the spatial and temporal patterns of mass movement or the environmental, human, or geomorphic consequences of slides. Landslide inventory maps are tedious to compile, difficult to make in vegetated terrain using conventional techniques, and tend to be subjective. In addition, most landslide inventories simply outline landslide boundaries and do not offer information about landslide mechanics as manifested by internal deformation features. In an alternative approach, we constructed accurate, high-resolution DEMs from airborne laser altimetry (LIDAR) data to characterize a large landslide complex and surrounding terrain near Christchurch, New Zealand. One-dimensional, circular (2-D) and spherical (3-D) statistics are used to map the local topographic roughness in the DEMs over a spatial scale of 1.5 to 10 m. The bedrock landslide is rougher than adjacent untailed terrain and any of the statistics can be employed to automatically detect and map the overall slide complex. Furthermore, statistics that include a measure of the local variability of aspect successfully delineate four kinematic units within the gently sloping tower half of the slide. Features with a minimum size of surface folds that have a wavelength of about 11 to 12 m and amplitude of about 1 m are readily mapped. Two adjacent earthflows within the landslide complex are distinguished by a contrast in median roughness, and texture and continuity of roughness elements. The less active of the earthflows has a surface morphology that presumably has been smoothed by surface processes. The Laplacian operator also accurately maps the kinematic units and the folds and longitudinal levees within and at the margins of the units. Finally, two-dimensional power spectra analyses are used to quantify how roughness varies with length scale. These results indicate that no dominant length scale of roughness exists for smooth, unfailed terrain. In contrast, zones with different styles of landslide deformation exhibit distinctive spectral peaks that correspond to the scale of deformation features, such as the compression folds. The topographic-based analyses described here may be used to objectively delineate landslide features, generate mechanical inferences about landslide behavior, and evaluate relatively the recent activity of slides. Published by Elsevier Science B.V.
McKenna JP, Santi PM, Amblard X and Negri J (2012), "Effects of soil-engineering properties on the failure mode of shallow landslides", Landslides., June, 2012. Vol. 9(2), pp. 215-228.
Abstract: Some landslides mobilize into flows, while others slide and deposit material immediately down slope. An index based on initial dry density and fine-grained content of soil predicted failure mode of 96 landslide initiation sites in Oregon and Colorado with 79% accuracy. These material properties can be used to identify potential sources for debris flows and for slides. Field data suggest that loose soils can evolve from dense soils that dilate upon shearing. The method presented herein to predict failure mode is most applicable for shallow (depth < 5 m), well-graded soils (coefficient of uniformity > 8), with few to moderate fines (fine-grained content < 18%), and with liquid limits < 40.
Medicus G (2009), "Massenbewegungen und Vegetationsbedeckung". Thesis at: University of Innsbruck, Division of Geotechnical and Tunnel Engineering.
Meisina C and Scarabelli S (2007), "A comparative analysis of terrain stability models for predicting shallow landslides in colluvial soils ", Geomorphology . Vol. 87(3), pp. 207 - 223.
Abstract: Most of the slopes of the hilly areas of the Apennines are composed of colluvial soils originating from the weathering of the bedrock and down slope transportation. Shallow slides affect this superficial cover, depend largely on the surface topography and are a recurrent problem. SINMAP and SHALSTAB are terrain stability models that combine steady state hydrology assumptions with the infinite slope stability model to quantify shallow slope stability. They have a similar physical basis but they use different indices to quantify instability. The purposes of this study are to test and compare the approaches of SINMAP and SHALSTAB models for slope stability analysis and to compare the results of these analyses with the locations of the shallow landslides that occurred on November 2002 in an area of the Oltrepo Pavese (Northern Apennines). The territory of S. Giuletta, characterized by clayey–silty colluvial soils, represents the test site. The Digital Elevation Model was constructed from a 1:5000 scale contour map and was used to estimate the slope of the terrain as well as the potential soil moisture conditions. In situ and laboratory tests provided the basis for measuring values for soil hydraulic and geotechnical parameters (moisture content, soil suction, Atterberg limits, methylene blue dye adsorption, hydraulic conductivity). Soil thickness was extracted from a soil database. An inventory of landslide from interpretation of aerial photographs and field surveys was used to document sites of instability (mostly soil slips) and to provide a test of model performance by comparing observed landslide locations with model predictions. The study discusses the practical advantages and limitations of the two models in connection with the geological characteristics of the studied area, which could be representative of similar geological contexts in the Apennines.
Menashe E (1998), "Vegetation and erosion: A literature survey", Environmental Education assessment & Management. Greenbelt Consulting, Clinton., In Native Plants: Propagation and Planting. Corvallis, Oregon, December 9-10, 1998. , pp. 130-135. Forest Research Laboratory.
Abstract: Surface Erosion and mass-soil losses from landslides are of great concern to land managers. Accelerated erosion and slope instability can be caused or exacerbated by human activities. Increased erosion can cause adverse cumulative watershed effects by increasing sedimentation, degrading water supplies, reducing forest productivity, destroying anadromous fish habitat, and degrading other critcial environmental values. Mature, structurally and floristically complex, plant communities, significantly reduce surface erosion and contribute greatly to maintaining slope stability. Vegetation management of forested, coastal, urban, agriculnural, and riparian areas should conserve and maintain adequate plant cover to be effective. The relative effectiveness of vegetation in any specific locale will be a function of quality of vegetation, topography, slope, hydrology, geology, and soils.
Mergili M (2008), "r.avalanche - A model for simulating runout of granular flows (debris flows and snow avalanches)"
Mergili M (2008), "r.debrisflow - A model framework for simulating mobilization and movement of debris flow"
Mergili M and Fellin W (2009), "Slope stability and geographic information systems: an advanced model versus the infinite slope stability approach", In Proceedings of the international conference "mitigation of natural hazards and risks-georisk". , pp. 119-124.
Abstract: Landslides starting from unstable slopes threat people, buildings, and infrastructures all over the world and are therefore intensively studied. On the one hand, engineers use sophisticated models to identify hazardous slopes, mostly based on longitudinal sections. On the other hand, less sophisticated models are used in combination with Geographic Information Systems (GIS) in order to cover larger areas ranging from single slopes to entire countries. The present paper describes an attempt to combine these two philosophies and to come up with a spatially distributed model for slope stability going beyond the widely used infinite slope stability concept.
Mergili M, Fellin W, Moreiras SM and Stotter J (2012), "Simulation of debris flows in the Central Andes based on Open Source GIS: possibilities, limitations, and parameter sensitivity", Natural Hazards., April, 2012. Vol. 61(3), pp. 1051-1081.
Abstract: A GIS-based model framework, designed as a raster module for the Open Source software GRASS, was developed for simulating the mobilization and motion of debris flows triggered by rainfall. Designed for study areas up to few square kilometres, the tool combines deterministic and empirical model components for infiltration and surface runoff, detachment and sediment transport, slope stability, debris flow mobilization, and travel distance and deposition. The model framework was applied to selected study areas along the international road from Mendoza (Argentina) to Central Chile. The input parameters were investigated at the local scale. The model was run for a number of rainfall scenarios and evaluated using field observations and historical archives in combination with meteorological data. The sensitivity of the model to a set of key parameters was tested. The major scope of the paper is to highlight the capabilities of the model-and of this type of models in general-as well as its limitations and possible solutions.
Mergili M, Geitner C, Moran AP, Fecht M and Stötter J (2006), "SOILSIM–a GIS-based framework for data-extensive modelling of the spatial distribution of soil hydrological characteristics in small alpine catchments", Angewandte Geoinformatik. , pp. 444-453.
Abstract: SOILSIM is a GIS-based modelling framework for the spatial interpolation of soil characteristics from individual points to a raster map. It was designed for providing a reliable approximation of the hydrological characteristics of the soils in small alpine catchments with a minimum of input required, and fully dependent on open source products (GRASS and R). A table representing the soil characteristics and a set of habitat maps are required as input. The program operates in two major steps. (1) A linear multiple regression is fitted for each soil variable (the predictors are chosen using ANOVA). The regression equations are then applied to raster maps of the predictor variables. (2) Hydrologically relevant soil characteristics (e.g. field capacity, saturated hydraulic conductivity) are calculated as response to the modelled soil variables.
SOILSIM was applied to the Stampfanger catchment (near Kitzbühel, Tyrol, Austria; 23.1 km²). The results of the study indicated that the method is quick and easy, but that it has to be applied with much caution and with qualitatively and quantitatively sufficient input data in order to provide reliable predictions for the variables under investigation.
Mergili M, Schratz K, Ostermann A and Fellin W (2012), "Physically-based modelling of granular flows with Open Source GIS", Natural Hazards and Earth System Sciences. Vol. 12(1), pp. 187-200.
Abstract: Computer models, in combination with Geographic Information Sciences (GIS), play an important role in up-to-date studies of travel distance, impact area, velocity or energy of granular flows (e.g. snow or rock avalanches, flows of debris or mud). Simple empirical-statistical relationships or mass point models are frequently applied in GIS-based modelling environments. However, they are only appropriate for rough overviews at the regional scale. In detail, granular flows are highly complex processes and physically-based, distributed models are required for detailed studies of travel distance, velocity, and energy of such phenomena. One of the most advanced theories for understanding and modelling granular flows is the Savage-Hutter type model, a system of differential equations based on the conservation of mass and momentum. The equations have been solved for a number of idealized topographies, but only few attempts to find a solution for arbitrary topography or to integrate the model with GIS are known up to now. The work presented is understood as an initiative to integrate a fully physically-based model for the motion of granular flows, based on the extended Savage-Hutter theory, with GRASS, an Open Source GIS software package. The potentials of the model are highlighted, employing the Val Pola Rock Avalanche (Northern Italy, 1987) as the test event, and the limitations as well as the most urging needs for further research are discussed.
Merz A, Alewell C, Hiltbrunner E and Baenninger D (2009), "Plant-compositional effects on surface runoff and sediment yield in subalpine grassland", Journal of Plant Nutrition and Soil Science-zeitschrift Fur Pflanzenernahrung Und Bodenkunde., December, 2009. Vol. 172(6), pp. 777-788.
Abstract: Soil erosion such as sheet erosion is frequently encountered in subalpine grassland in the Urseren Valley (Swiss Central Alps). Erosion damages have increased enormously in this region during the last 50 y, most likely due to changes in land-use practices and due to the impact of climatic changes. In order to estimate the effect of vegetation characteristics on surface runoff and sediment loss, we irrigated 22 pasture plots of 1 m(2) during 1 h at an intense rain rate of 50 mm h(-1) in two field campaigns using a portable rain simulator. The rain-simulation plots differed in plant composition (herb versus grass dominance) and land-use intensity but not in plant cover (>90%) nor in soil conditions. Prior to the second rain-simulation campaign, aboveground vegetation was clipped in order to simulate intense grazing. The generated surface runoffs, sediment loss, relative water retention in the aboveground vegetation, and changes in soil moisture were quantified. Runoff coefficient varied between 0.1% and 25%, and sediment loss ranged between 0 and 0.053 g m(-2). Thus, high infiltration rates and full vegetation cover resulted in very low erosion rates even under such extreme rain events. Surface runoff did not differ significantly between herb- and grass-dominated plots. However, clipping had a notable effect on surface runoff in the test plots under different land-use intensity. In plots without or with intensive use, surface runoff decreased after clipping whereas in extensively used plots, surface runoff increased after the clipping. This opposite effect was mainly explained by higher necromass and litter presence at the extensively used plots after the clipping treatment. The results obtained here contribute to a better understanding of the importance of vegetation characteristics on surface-runoff formation, thus, on soil-erosion control. Overall, we delineate vegetation parameters to be crucial in soil-erosion control which are directly modified by the land-use management.
Metternicht G, Hurni L and Gogu R (2005), "Remote sensing of landslides: An analysis of the potential contribution to geo-spatial systems for hazard assessment in mountainous environments", Remote Sensing of Environment., October, 2005. Vol. 98(2-3), pp. 284-303.
Abstract: Natural hazards like landslides, avalanches, floods and debris flows can result in enormous property damage and human casualties in mountainous regions. Switzerland has always been exposed to a wide variety of natural hazards mostly located in its alpine valleys. Recent natural disasters comprising avalanches, floods, debris flows and slope instabilities led to substantial loss of life and damage to property, infrastructure, cultural heritage and environment. In order to offer a solid technical infrastructure, a new concept and expert-tool based on an integrated web-based database/GIS structure is being developed under HazNETH. Given the HazNETH database design contemplates the detection and mapping of diagnostic features from remote sensors (e.g., ground, air and space borne) this paper analyses the use of remote sensing data in landslides studies during the 1980s, 1990s and 2000s, including a discussion of its potential and research challenges as result of new operational and forthcoming technologies such as the very high spatial resolution optical and infrared imagery of Ikonos, Quickbird, IRS CartoSat-1, ALOS, the satellite based interferometric SAR (InSAR and DInSAR of Radarsat, ERS, Envisat, TerraSAR-X, Cosmo/SkyMed, ALOS), micro-satellites like the Pleiades, DMC, RapidEye, airborne LASER altimetry or ground-based differential interferometric SAR. The use of remote sensing data, whether air-, satellite- or ground-based varies according to three main stages of a landslide related study, namely a) detection and identification; b) monitoring; c) spatial analysis and hazard prediction. Accordingly, this paper presents and discusses previous applications of remote sensing tools as related to these three main phases, proposing a conceptual framework for the contribution of remote sensing to the design of databases for natural hazards like debris flows, and identifying areas for further research. (C) 2005 Elsevier Inc. All rights reserved.
Meusburger K and Alewell C (2008), "Impacts of anthropogenic and environmental factors on the occurrence of shallow landslides in an alpine catchment (Urseren Valley, Switzerland)", Natural Hazards and Earth System Sciences. Vol. 8(3), pp. 509-520. Copernicus Gesellschaft Mbh.
Abstract: Changes in climate and land use pose a risk to stability of alpine soils, but the direction and magnitude of the impact is still discussed controversially with respect to the various alpine regions. In this study, we explicitly consider the influence of dynamic human-induced changes on the occurrence of landslides in addition to natural factors. Our hypothesis was that if changes in land use and climate have a significant influence on the occurrence of landslides we would see a trend in the incidence of landslides over time. We chose the Urseren Valley in the Central Swiss Alps as investigation site because the valley is dramatically affected by landslides and the land use history is well documented. Maps of several environmental factors were used to analyse the spatial landslide pattern. In order to explain the causation of the temporal variation, time-series (45 years) of precipitation characteristics, cattle stocking and pasture maps were compared to a series of seven landslide investigation maps between 1959 and 2004. We found that the area affected by landslides increased by 92% from 1959 to 2004. Even though catchment characteristics like geology and slope largely explain the spatial variation in landslide susceptibility (68%), this cannot explain the temporal trend in landslide activity. The increase in stocking numbers and the increased intensity of torrential rain events had most likely an influence on landslide incidence. In addition, our data and interviews with farmers pointed to the importance of management practice.
Meyer NK, Dyrrdal AV, Frauenfelder R, Etzelmuller B and Nadim F (2012), "Hydrometeorological threshold conditions for debris flow initiation in Norway", Natural Hazards and Earth System Sciences. Vol. 12(10), pp. 3059-3073.
Abstract: Debris flows, triggered by extreme precipitation events and rapid snow melt, cause considerable damage to the Norwegian infrastructure every year. To define intensity-duration (ID) thresholds for debris flow initiation critical water supply conditions arising from intensive rainfall or snow melt were assessed on the basis of daily hydrometeorological information for 502 documented debris flow events. Two threshold types were computed: one based on absolute ID relationships and one using ID relationships normalized by the local precipitation day normal (PDN). For each threshold type, minimum, medium and maximum threshold values were defined by fitting power law curves along the 10th, 50th and 90th percentiles of the data population. Depending on the duration of the event, the absolute threshold intensities needed for debris flow initiation vary between 15 and 107 mm day(-1). Since the PDN changes locally, the normalized thresholds show spatial variations. Depending on location, duration and threshold level, the normalized threshold intensities vary between 6 and 250 mm day(-1). The thresholds obtained were used for a frequency analysis of over-threshold events giving an estimation of the exceedance probability and thus potential for debris flow events in different parts of Norway. The absolute thresholds are most often exceeded along the west coast, while the normalized thresholds are most frequently exceeded on the west-facing slopes of the Norwegian mountain ranges. The minimum thresholds derived in this study are in the range of other thresholds obtained for regions with a climate comparable to Norway. Statistics reveal that the normalized threshold is more reliable than the absolute threshold as the former shows no spatial clustering of debris flows related to water supply events captured by the threshold.
Michoud C, Jaboyedoff M, Derron M-H, Nadim F and Leroi E (2011), "Classification of landslide-inducing anthropogenic activities", In Proc. of the 5th Canadian Conference on Geotechnique and Natural Hazards. Kelowna , pp. 10.
Abstract: Although landslides are usually considered typical examples of natural hazards, they can be influenced by human activities. This paper introduces a new classification of anthropogenic activities affecting slope stability conditions. It takes into account the conceptual processes leading to landslides and the distinction between destabilization factors and triggering factors. The classification was tested and improved through fifty-eight relevant and/or well-known case studies.
Mikos M (2011), "Landslides: A state-of-the art on the current position in the landslide research community", Landslides., December, 2011. Vol. 8(4), pp. 541-551.
Abstract: The international journal Landslides (ISSN 1612-510X), launched in 2004 and published by Springer Verlag, soon gained international recognition as the only specialized scientific journal in the world dedicated to different aspects of landslides, and as one of the leading world journals in the field of geological engineering. After 7 years, seven published volumes with 28 issues and 290 published papers on 2,794 pages, there is time to make a comparison with other related journals that also cover the field of landslide risk mitigation. The critical review of these seven publishing years was done using ISI Journal Citation Reports produced by Thomson Reuters, and available scientometric data from the ISI Web of Knowledge and SCOPUS. The data presented in this paper and the analysis shown may help the Editorial Board to further improve the journal into the direction of a high quality scientific journal with even higher impact on the international research community in the field of landslide risk mitigation.
Mikos M, Petkovsek A and Majes B (2009), "Mechanisms of landslides in over-consolidated clays and flysch - Activity scale and targeted region: national", Landslides., December, 2009. Vol. 6(4), pp. 367-371.
Abstract: In this report, we present the situation in Slovenia, Europe with regard to natural hazards, emphasizing land-sliding problems. Furthermore, we shortly present the University of Ljubljana and the Faculty of Civil and Geodetic Engineering as the new member of the ICL that was selected to be the World Center of Excellence on Landslide Risk Reduction for the period of 2008-2013 with the project entitled "Mechanisms of landslides in overconsolidated clays and flysch" in the Activity scale and targeted region as "National." Some preliminary results of this project are shortly presented at the end.
Milledge DG, Griffiths DV, Lane SN and Warburton J (2012), "Limits on the validity of infinite length assumptions for modelling shallow landslides", Earth Surface Processes and Landforms., September, 2012. Vol. 37(11), pp. 1158-1166.
Abstract: The infinite slope method is widely used as the geotechnical component of geomorphic and landscape evolution models. Its assumption that shallow landslides are infinitely long (in a downslope direction) is usually considered valid for natural landslides on the basis that they are generally long relative to their depth. However, this is rarely justified, because the critical length/depth (L/H) ratio below which edge effects become important is unknown. We establish this critical L/H ratio by benchmarking infinite slope stability predictions against finite element predictions for a set of synthetic two-dimensional slopes, assuming that the difference between the predictions is due to error in the infinite slope method. We test the infinite slope method for six different L/H ratios to find the critical ratio at which its predictions fall within 5% of those from the finite element method. We repeat these tests for 5000 synthetic slopes with a range of failure plane depths, pore water pressures, friction angles, soil cohesions, soil unit weights and slope angles characteristic of natural slopes. We find that: (1) infinite slope stability predictions are consistently too conservative for small L/H ratios; (2) the predictions always converge to within 5% of the finite element benchmarks by a L/H ratio of 25 (i.e. the infinite slope assumption is reasonable for landslides 25 times longer than they are deep); but (3) they can converge at much lower ratios depending on slope properties, particularly for low cohesion soils. The implication for catchment scale stability models is that the infinite length assumption is reasonable if their grid resolution is coarse (e.g. >25?m). However, it may also be valid even at much finer grid resolutions (e.g. 1?m), because spatial organization in the predicted pore water pressure field reduces the probability of short landslides and minimizes the risk that predicted landslides will have L/H ratios less than 25. Copyright (c) 2012 John Wiley & Sons, Ltd.
Mitasova H, Harmon RS, Weaver KJ, Lyons NJ and Overton MF (2012), "Scientific visualization of landscapes and landforms", Geomorphology., January, 2012. Vol. 137(1), pp. 122-137.
Abstract: Scientific visualization of geospatial data provides highly effective tools for analysis and communication of information about the land surface and its features, properties, and temporal evolution. Whereas single-surface visualization of landscapes is now routinely used in presentation of Earth surface data, interactive 3D visualization based upon multiple elevation surfaces and cutting planes is gaining recognition as a powerful tool for analyzing landscape structure based on multiple return Light Detection and Ranging (LiDAR) data. This approach also provides valuable insights into land surface changes captured by multi-temporal elevation models. Thus, animations using 2D images and 3D views are becoming essential for communicating results of landscape monitoring and computer simulations of Earth processes. Multiple surfaces and 3D animations are also used to introduce novel concepts for visual analysis of terrain models derived from time-series of LiDAR data using multi-year core and envelope surfaces. Analysis of terrain evolution using voxel models and visualization of contour evolution using isosurfaces has potential for unique insights into geometric properties of rapidly evolving coastal landscapes. In addition to visualization on desktop computers, the coupling of GIS with new types of graphics hardware systems provides opportunities for cutting-edge applications of visualization for geomorphological research. These systems include tangible environments that facilitate intuitive 3D perception, interaction and collaboration. Application of the presented visualization techniques as supporting tools for analyses of landform evolution using airborne LiDAR data and open source geospatial software is illustrated by two case studies from North Carolina, USA. (C) 2011 Elsevier B.V. All rights reserved.
Mitavsova H and Mitas L (1993), "Interpolation by regularized spline with tension: I. Theory and implementation", Mathematical geology. Vol. 25(6), pp. 641-655. Springer.
Abstract: Bivariate and trivariate functions for interpolation from scattered data are derived. They are constructed by explicit minimization of a general smoothness functional, and they include a tension parameter that controls the character of the interpolation function (e.g., for bivariate case the surface can be tuned from a “membrane” to a “thin steel plate”), Tension can be applied also in a chosen direction, for modeling of phenomena with a simple type of anisotropy. The functions have regular derivatives of all orders everywhere. This makes them suitable for analysis of surface geometry and for direct application in models where derivatives are necessary. For processing of large datasets (thousands of data points), which are now common in geosciences, a segmentation algorithm with a flexible size of overlapping neighborhood is presented. Simple examples demonstrating flexibility and accuracy of the functions are presented.
Moine M, Puissant A and Malet J-P (2009), "Detection of landslides from aerial and satellite images with a semi-automatic method. Application to the Barcelonette basin (Alpes-de-Haute-Provence, France)", In International Conference “Landslide Processes: From Geomorphological Mapping to Dynamic Modelling”. Strasbourg, France , pp. 63-68.
Abstract: Until now, visual photo-interpretation techniques combined to ground survey remains the most used method to locate and characterize landslides. New perspectives in using remote sensing for landslides location are now offered by the availability of new very high spatial esolution images and by the development of object-oriented image analysis. In this context, the aim of this paper is to propose a semi-automatic method to locate landslides based on very high spatial resolution (aerial and satellite) images and by using expert knowledge on landslides. This approach is based on (1) a calibration step which consists to translate qualitative indicators derived from expert knowledge (by a photo-interpretation technique) in quantitative indicators and (2) a validation step which allows testing the relevance of these indicators to detect landslides by using an object-oriented method and by only using (aerial or satellite) images with different spatial, spectral and temporal resolutions. Results are (1) a formal and generic grid characterizing landslides and (2) the identification of relevant criteria to extract landslides.
Molinari ME, Cannata M, Begueria S and Ambrosi C (2012), "GIS-based Calibration of MassMov2D", Transactions In Gis., April, 2012. Vol. 16(2), pp. 215-231. Wiley-blackwell.
Abstract: MassMov2D is a numerical model for simulating runout and deposition of landslide phenomena over a complex topography that is implemented in the free GIS PCRaster. This research aims at improving the mechanism of MassMov2D calibration and verifying its capability of representing complex landslides. In this article the authors present the enhancement of the MassMov2D code due to the introduction of the Nash-Sutcliffe coefficient for model efficiency calculation; this enables the replacement of the inefficient trial and error approach used for sensitivity analysis and calibration with a semi-automatic procedure. During this research the improved code was tested in a case study located on the Canaria Valley (Switzerland) where a complex landslide occurred. An optimal set of parameters were calculated for evaluating the effects of a possible further slope failure. The availability of a unique dataset of high resolution digital elevation models just before and after the collapse allowed precise evaluation of the sensitivity and calibration of the model with the new procedure. The results demonstrate that this model is capable of reproducing the observed deposits even though some model limitations were identified in steep slope areas. Finally the study presents the expected scenario due to a future landslide.
Möller M, Volk M, Friedrich K and Lymburner L (2008), "Placing soil-genesis and transport processes into a landscape context: A multiscale terrain-analysis approach", Journal of Plant Nutrition and Soil Science. Vol. 171, pp. 419-430.
Abstract: Landforms and landscape context are of particular importance in understanding the processes of soil genesis and soil formation in the spatial domain. Consequently, many approaches for soil generation are based on classifications of commonly available digital elevation models (DEM). However, their application is often restricted by the lack of transferability to other, more heterogeneous, landscapes. Part of the problem is the lack of broadly accepted definitions of topographic location based on landscape context. These issues arise because of: (1) the scale dependencies of landscape pattern and processes, (2) different DEM qualities, and (3) different expert perceptions. To address these problems, we suggest a hierarchical terrain-classification procedure for defining landscape context. The classification algorithm described in this paper handles object detection and classification separately. Landscape objects are defined at multiple scales using a region-based segmentation algorithm which allows each object to be placed into a hierarchical landscape context. The classification is carried out using the terrain attribute mass-balance index across a range of scales. Soil genesis and transport processes at established field sites were used to guide the classification process. The method was tested in Saxony-Anhalt (Germany), an area that contains heterogeneous land surfaces and soil substrates. The resulting maps represent adaptation degrees between classifications and 191 semantically identified random samples. The map with the best adaptation has an overall accuracy of 89%.
Mondini AC, Chang K-T and Yin H-Y (2011), "Combining multiple change detection indices for mapping landslides triggered by typhoons", Geomorphology., November, 2011. Vol. 134(3-4), pp. 440-451.
Abstract: An important part of landslide research is the interpretation and delineation of landslides, which has increasingly been based on high-resolution satellite images in recent years. Using pre- and post-event FORMOSAT-2 satellite images as the data sources, this study presents a new method that combines four change detection techniques for mapping shallow landslides triggered by typhoons in Taiwan. The four techniques are normalized differential vegetation index (NDVI), spectral angle, principal component analysis, and independent component analysis. We apply the multiple change detection (MCD) technique to map landslides triggered by two typhoons of vastly different magnitudes. Comparisons are then made between MCD results with landslide inventory maps compiled by using a single index (change in NDVI) in one case study and visual analysis in another. Comparison results show that MCD can perform better than change in NDVI in dealing with old landslides and landslides with non-homogeneous spectral responses. MCD is also able to detect small landslides, which are often missed by visual analysis. Additionally, landslide maps prepared by MCD include runout features of sediment deposits from debris flows. A relatively fast processing chain, MCD is expected to become a useful new tool for emergency management after a typhoon event, which occurs on average four to five times a year in Taiwan. (C) 2011 Elsevier B.V. All rights reserved.
Mondini AC, Guzzetti F, Reichenbach P, Rossi M, Cardinali M and Ardizzone F (2011), "Semi-automatic recognition and mapping of rainfall induced shallow landslides using optical satellite images", Remote Sensing of Environment., July, 2011. Vol. 115(7), pp. 1743-1757.
Abstract: We present a method for the semi-automatic recognition and mapping of recent rainfall induced shallow landslides. The method exploits VHR panchromatic and HR multispectral satellite images, and was tested in a 9.4 km(2) area in Sicily, Italy, where on 1 October 2009 a high intensity rainfall event caused shallow landslides, soil erosion, and inundation. Pre-event and post-event images of the study area taken by the QuickBird satellite, and information on the location and type of landslides obtained in the field and through the interpretation of post-event aerial photographs, were used to construct and validate a set of terrain classification models. The models classify each image element (pixel) based on the probability that the pixel contains (or does not contain) a new rainfall induced landslide. To construct and validate the models, a procedure in five steps was adopted. First, the pre-event and the post-event images were pan-sharpened, ortho-rectified, co-registered, and corrected for atmospheric disturbance. Next, variables describing changes between the pre-event and the post-event images attributed to landslide occurrence were selected. Next, three classification models were calibrated in a training area using different multivariate statistical techniques. The calibrated models were then applied in a validation area using the same set of independent variables, and the same statistical techniques. Lastly, combined terrain classification models were prepared for the training and the validation areas. The performances of the models were evaluated using four-fold plots and receiver operating characteristic curves. The method proved capable of detecting and mapping the new rainfall induced landslides in the study area. We expect the method to be capable of detecting analogous shallow landslides caused by similar (rainfall) or different (e.g. earthquake) triggers, provided that the event slope failures leave discernable features captured by the post-event satellite images, and that the terrain information and satellite images are of adequate quality. The proposed method can facilitate the rapid production of accurate landslide event-inventory maps, and we expect that it will improve our ability to map landslides consistently over large areas. Application of the method will advance our ability to evaluate landslide hazards, and will foster our understanding of the evolution of landscapes shaped by mass-wasting processes. (C) 2011 Elsevier Inc. All rights reserved.
Monserrat O, Moya J, Luzi G, Crosetto M, Gili JA and Corominas J (2013), "Non-interferometric GB-SAR measurement: application to the Vallcebre landslide (eastern Pyrenees, Spain)", Natural Hazards and Earth System Science. Vol. 13(7), pp. 1873-1887.
Abstract: In the last decade, ground-based interferometry has proven to be a powerful technique for continuous deformation monitoring of landslides, glaciers, volcanoes, or manmade structures, among others. However, several limitations need to be addressed in order to improve the performances of the technique, especially for long-term monitoring. These limitations include the reduction of measurable points with an increase in the period of observation, the ambiguous nature of the phase measurements, and the influence of the atmospheric phase component. In this paper, a new procedure to process the amplitude component of ground-based synthetic aperture radar (GB-SAR) data acquired in discontinuous mode is compared and validated. The use of geometric features of the amplitude images combined with a matching technique will allow the estimation of the displacements over specific targets. Experimental results obtained during 19 months, in eight different campaigns carried out in the active landslide of Vallcebre (eastern Pyrenees, Spain), were analysed. During the observed period, from February 2010 to September 2011, displacements up to 80 cm were measured. The comparison with other surveying technique shows that the precision of the method is below 1 cm.
Montgomery DR and Dietrich WE (1994), "A Physically-based Model For the Topographic Control On Shallow Landsliding", Water Resources Research., April, 1994. Vol. 30(4), pp. 1153-1171. Amer Geophysical Union.
Abstract: A model for the topographic influence on shallow landslide initiation is developed by coupling digital terrain data with near-surface through flow and slope stability models. The hydrologic model TOPOG (O'Loughlin, 1986) predicts the degree of soil saturation in response to a steady state rainfall for topographic elements defined by the intersection of contours and flow tube boundaries. The slope stability component uses this relative soil saturation to analyze the stability of each topographic element for the case of cohesionless soils of spatially constant thickness and saturated conductivity. The steady state rainfall predicted to cause instability in each topographic element provides a measure of the relative potential for shallow landsliding. The spatial distribution of critical rainfall values is compared with landslide locations mapped from aerial photographs and in the field for three study basins where high-resolution digital elevation data are available: Tennessee Valley in Marin County, California; Mettman Ridge in the Oregon Coast Range; and Split Creek on the Olympic Peninsula, Washington. Model predictions in each of these areas are consistent with spatial patterns of observed landslide scars, although hydrologic complexities not accounted for in the model (e.g., spatial variability of soil properties and bedrock flow) control specific sites and timing of debris flow initiation within areas of similar topographic control.
Montgomery DR, Dietrich WE, Torres R, Anderson SP, Heffner JT and Loague K (1997), "Hydrologic response of a steep, unchanneled valley to natural and applied rainfall", Water Resources Research. Vol. 33(1), pp. 91-109.
Abstract: Observations from natural rain storms and sprinkling experiments at a steep zero-order catchment in the Oregon Coast Range demonstrate the importance of flow through near-surface bedrock on runoff generation and pore pressure development in shallow colluvial soils. Sprinkling experiments, involving irrigation of the entire 860 m2 catchment at average intensities of 1.5 and 3.0 mm/h, permitted detailed observation of runoff and the development of subsurface saturation under controlled conditions. A weir installed to collect flow through the colluvium at the base of the catchment recovered runoff equal to one third to one half of the precipitation rate during quasi-steady irrigation. Three key observations demonstrate that a significant proportion of storm runoff flows through near-surface bedrock and illustrate the importance of shallow bedrock flow in pore pressure development in the overlying colluvial soil: (1) greater discharge recovery during both the experiments and natural rainfall at a weir installed approximately 15 m downslope of the weir at the base of the catchment, (2) spatially discontinuous patterns of positive pressure head in the colluvium during steady sprinkling, and (3) local development of upward head gradients associated with flow from weathered rock into the overlying colluvium during high-intensity rainfall. Data from natural storms also show that smaller storms produce no significant runoff or piezometric response and point to a critical intensity-duration rainfall to overcome vadose zone storage. Together these observations highlight the role of interaction between flow in colluvium and near-surface bedrock in governing patterns of soil saturation, runoff production, and positive pore pressures.
Montgomery DR, Schmidt KM, Greenberg HM and Dietrich WE (2000), "Forest clearing and regional landsliding", Geology., April, 2000. Vol. 28(4), pp. 311-314. Geological Soc America, Inc.
Abstract: The influence of forest clearing on landsliding is central to longstanding concern over the effects of timber harvesting on slope stability. Here we document a strong topographic control on shallow landsliding by combining unique ground-based landslide surveys in an intensively monitored study area with digital terrain modeling using high-resolution laser altimetry and a coarser resolution regional study of 3224 landslides. As predicted by our digital terrain-based model, landslides occur disproportionately in steep, convergent topography. In terrain predicted to be at low risk of slope failure, a random model performs equally well to our mechanism-based model. Our monitoring shows that storms with 24 hr rainfall recurrence intervals of less than 4 yr triggered landslides in the decade after forest clearing and that conventional monitoring programs can substantially underestimate the effects of forest clearing. Our regional analysis further substantiates that forest clearing dramatically accelerates shallow landsliding in steep terrain typical of the Pacific Northwest.
Montgomery DR, Sullivan K and Greenberg HM (1998), "Regional test of a model for shallow landsliding", Hydrological Processes. Vol. 12(6), pp. 943-955. John Wiley & Sons, Ltd.
Abstract: Landslides mapped in 14 watershed analyses in Oregon and Washington provide a regional test of a model for shallow landsliding. A total of 3224 landslides were mapped in watersheds covering 2993 km2 and underlain by a variety of lithologies, including Tertiary sedimentary rocks of the Coast Ranges, volcanic rocks of the Cascade Range and Quaternary glacial sediments in the Puget Lowlands. GIS (geographical information system) techniques were used to register each mapped landslide to critical rainfall values predicted from a theoretical model for the topographic control on shallow landsliding using 30 m DEMs (digital elevation models). A single set of parameter values appropriate for simulating slide hazards after forest clearing was used for all watersheds to assess the regional influence of topographic controls on shallow landsliding. Model performance varied widely between watersheds, with the best performance generally in steep watersheds underlain by shallow bedrock and the worst performance in generally low gradient watersheds underlain by thick glacial deposits. Landslide frequency (slides/km2) varied between physiographic provinces but yielded consistent patterns of higher slide frequency in areas with lower critical rainfall values. Simulations with variable effective cohesion predicted that high root strength effectively limits shallow landsliding to topographic hollows with deep soils and locations that experience excess pore pressures, but that low root strength leads to higher probabilities of failure across a greater proportion of the landscape. © 1998 John Wiley & Sons, Ltd.
Montrasio L and Valentino R (2007), "Experimental analysis and modelling of shallow landslides", Landslides., September, 2007. Vol. 4(3), pp. 291-296. Springer Heidelberg.
Abstract: The paper presents the results of some experimental tests reproducing the triggering mechanism of a special kind of shallow landslides induced by rainfalls (soil slip) in a physical 1-g model. The experimental data have been employed to verify the capability of a simplified stability model to describe the phenomenon and to back-analyse its occurrence in a case history (Pizzo d'Alvano, Campania Region 1998). The method enables a direct correlation between the safety factor of a slope and rainfall intensity, as well as antecedent rainfalls.
Moore R, Carey JM and McInnes RG (2010), "Landslide behaviour and climate change: predictable consequences for the Ventnor Undercliff, Isle of Wight", Quarterly Journal of Engineering Geology and Hydrogeology. Vol. 43, pp. 367-370.
Abstract: The Ventnor Undercliff, located on the south coast of the Isle of Wight, is an ancient landslide complex of marginal stability that is prone to ground movement and occasional landslide events. The impact of ground movement on property and services in the town has been significant in the past. Since 1995, the local authority has made a significant investment in continuous monitoring and analysis of weather and ground movement data at key sites amongst other landslide management initiatives. These data reveal strong relationships between antecedent rainfall, groundwater and ground movement rates, confirming that prolonged periods of heavy winter rainfall and excess groundwater levels are a fundamental control on landslide behaviour. Climate change projections over the next 100 years point to significant increases in sea level and winter rainfall, which are expected to result in accelerated ground movement rates and more frequent landslide events in the Undercliff. There are concerns that hitherto marginally stable areas of the Undercliff may become unstable as a result of reactivation of ground movement and the occurrence of new landslides. In areas previously affected by ground movement or landslides, the frequency and rate of ground movement and landsliding is expected to increase. The paper presents historical and new data to demonstrate the relationships between rainfall and ground movement, and uses these to predict the likely impacts of climate change on future landslide behaviour. The paper concludes that climate change poses a very real threat and significant challenge to the future management and mitigation of the ground instability risks in the Ventnor Undercliff, which may be echoed for other similarly marginally stable ancient landslides in the UK.
Morgan RPC (1985), "Soil-erosion Measurement and Soil Conservation Research In Cultivated Areas of the Uk", Geographical Journal. Vol. 151(MAR), pp. 11-20.
Abstract: Agricultural soil erosion by both water and wind is a local scale problem in the UK, particularly on the sandy and sandy loam soils under continuous cereal production or market gardening in the midland and eastern counties of England. Mean annual rates of soil erosion by water on these soils in fields on hillslopes up to 11° can exceed 2 kg/m2 when rilling occurs, compared with a rate for top soil renewal of only about (0,1 kg/m2. Rates as high as 1.9 kg/m2 have been recorded in individual storms and storm rates greater than 0.2 kg/m2 can occur as frequently as in four years out of seven. Storm losses by wind erosion are of similar magnitude but those for gully erosion are much higher with rates reaching 15 to 19 kg/m2 in single storms. Research into soil conservation has been carried out on Experimental Husbandry Farms and by farmers and commercial organizations with a direct interest in the problem. It has been largely limited to the use of shelterbelts, guard crops, soil stabilizers and land imprinting or pressing to control wind erosion with virtually no work having been undertaken on water erosion control. There is a need for more fundamental research which will allow the mechanics of the control measures to be understood better and to enable their general applicability to be assessed more readily. Research projects with these aims in mind are described involving investigations of the effects of crop cover on splash erosion, tillage effects on soil erodibility and the simple modelling of the erosion system to predict the stability or instability of the soil resource under given systems of agricultural management.
Morgan RPC, Quinton JN, Smith RE, Govers G, Poesen JWA, Auerswald K, Chisci G, Torri D and Styczen ME (1998), "The European Soil Erosion Model (EUROSEM): A dynamic approach for predicting sediment transport from fields and small catchments", Earth Surface Processes and Landforms. Vol. 23(6), pp. 527-544.
Abstract: The European Soil Erosion Model (EUROSEM) is a dynamic distributed model, able to simulate sediment transport, erosion and deposition over the land surface by rill and interill processes in single storms for both individual fields and small catchments. Model output includes total runoff, total soil loss, the storm hydrograph and storm sediment graph. Compared with other erosion models, EUROSEM has explicit simulation of interill and rill flow; plant cover effects on interception and rainfall energy; rock fragment (stoniness) effects on infiltration, flow velocity and splash erosion; and changes in the shape and size of rill channels as a result of erosion and deposition. The transport capacity of runoff is modelled using relationships based on over 500 experimental observations of shallow surface flows. EUROSEM can be applied to smooth slope planes without rills, rilled surfaces and surfaces with furrows. Examples are given of model output and of the unique capabilities of dynamic erosion modelling in general.
Morgenstern NR and Martin CD (2008), "Landslides: seeing the ground", In Proceedings of the Tenth International Symposium on Landslides and Engineered Slopes. , pp. 3-24. Balkema, Christchurch.
Abstract: Landslide engineering requires the consideration of a number of complex processes ranging from geological and hydrogeological characterization to geomechanical characterization, analyses and risk management. This paper concentrates on recent advances that improve site characterization applied to landslide problems. It presents the view that one of the most exciting developments is the growing potential for application of Geographical Information Systems (GIS) and that making GIS geotechnically smart is a transformative development. Examples are given of integrating remote sensing data in GIS to improve visualization, mapping and movement characterization. Application of analysis of rockfall within GIS and complex slope stability evaluation with the aid of GIS are presented to illustrate recent developments and provide direction for future enhancements.
Morvan X, Saby NPA, Arrouays D, Le Bas C, Jones RJA, Verheijen FGA, Bellamy PH, Stephens M and Kibblewhite MG (2008), "Soil monitoring in Europe: A review of existing systems and requirements for harmonisation", Science of the Total Environment., February, 2008. Vol. 391(1), pp. 1-12.
Abstract: Official frameworks for soil monitoring exist in most member states of the European Union. However, the uniformity of methodologies and the scope of actual monitoring are variable between national systems. This review identifies the differences between existing systems, and describes options for harmonising soil monitoring in the Member States and some neighbouring countries of the European Union. The present geographical coverage is uneven between and within countries. In general, national and regional networks are much denser in northern and eastern regions than in southern Europe. The median coverage in the 50 km x 50 km EMEP cells applied all over the European Union, is 300 km(2) for one monitoring site. Achieving such minimum density for the European Union would require 4100 new sites, mainly located in southern countries (Italy, Spain, Greece), parts of Poland, Germany, the Baltic countries, Norway, Finland and France. Options are discussed for harmonisation of site density, considering various risk area and soil quality indicator requirements. (c) 2007 Elsevier B.V. All rights reserved.
Moser M (1980), "Zur Analyse von Hangbewegungen in schwachbindigen bis rolligen Lockergesteinen im alpinen Raum anlässlich von Starkniederschlägen", In Proc. of the IV International Congress Interpraevent 1980, Bad Ischl. Bad Ischl , pp. 121-148.
Abstract: Bei einer Analyse von Massenbewegungen sollte zwischen auslösenden Ursachen und mittelbaren Faktoren unterschieden werden. Als auslöselnde Ursachen für ein gehäuftes Auftreten von Hangbewegungen sind im Bereich von Oberkärnten und Osttirol eine bestimmte Dauer und Intensität von Niederschlägen erforderlich. Als mittelbare Faktoren sind die absolute Höhenlage, die Höhenlage über der lokalen Erosionsbasis, die geologischen und bodenmechanischen Kennziffern der Lockergesteine, die Hangneigung, die Hangmorphologie, die Vegetation und die anthropogene Beeinnussung zu nennen. Die faktorenanalytische Auswertung der hydrographischen und hypsographischen Charakteristiken von 62 Stationen in Oberkärnten und Osttirol läßt erkennen, daß bestimmte Regionen besonders gefährdet sind, das heißt in verstärktem Maße eine potentielle Anbruchsneigung besitzen.
Betroffen waren besonders Hänge von schwach bindigen bis rolligen Lockergesteinen (Hang- und Verwitterungsschutt, flvioglaziale Sedimente). Die Mächtigkeit ist gering (60% in der Klasse 1 bis 2 m. Bodenphysikalisch sind die betroffenen Böden als Mischböden mit großem Ungleichförmigkeitsgrad und Reibungswinkeln von 35 bis 40° anzusprechen.
Die größte Häufigkeit (ca. 30%) liegt bei einer Hangneigung von 35 bis 40°. Unter 20° und über 50° Hangneigung konnten keine Hangbewegungen beobachtet werden. Gefährdet waren besonders Terrassenkanten (knapp 60%) und Hangmulden (25%); an ungegliederten Hängen und Hangrücken sowie -rippen traten nur untergeordnet Hangbewegungen auf. Aus den geologischen und morphologischen Kennziffern lassen sich nur bedingt Größe und Volumen einer Hangbewegung voraussagen.
Mittlere Höhenlagen (700 bis 1400 m) begünstigen das Entstehen von Hangbewegungen, dabei liegt das Maximum der Anbruchshäufigkeit zwischen 50 bis 100 m über der lokalen Erosionsbasis. Zum Unterschied von den im Jahre 1966 entstandenen Hangbewegungen waren Freilandböden wesentlich stiirker gefährdet; über 90% der Hangbewegungen entstanden im Bereich von Wiesen, Weiden und Äckern. S- bis SE-exponierte Hänge waren zu über 70%, beteiligt. Ca. 30% der Hangbewegungen entstanden an künstlichen Böschungen von Feldwegen und Güterwegen.
Die untersuchten Hangbewegungen wiesen Breiten von 5 bis 45 m, Längen von 5 bis 100 m und Flächen von knapp 50 bis 4000 m2 auf. Die Tiefe lag zwischen 0,5 und 4 m; das T/L-Verhältnis zwischen 0,01 und 0,4. Positive Korrelationen ergelben sich zwischen den Längen, Breiten und Tiefen der Anbrüche.
Nach dem Bewegungsmechanismus sind die Hangbewegungen dem Gleiten und Fließen zuzuordnen. Aurgrund des T/L-Verhältnisses lassen sich drei Typen von Hangbewegungen ausscheiden, wobei Massenbewegungen mit ebenen, im wesentlichen hangparallelen Gleitflächen vorherrschen. An die Hanganbrüche schlossen sich durchwegs Sekundärmassenbewegungcn in Form von Mur- und Schuttgängen an. Keine oder nur geringe Vermurung zeigen nur 15% der Hangbewegungen.
Zur Stabilitätsuntersuchung wurde das Modell einer unendlich langen, durchströmten Böschung in schwach bindigen bis rolligen Böden herangezogen.
Moser M (1980), "Stand und Problematik der Ausscheidung von Gefahrenzonen in Hangbereichen im alpinen Raum", In Proc. of the IV International Congress Interpraevent 1980, Bad Ischl. Bad Ischl Vol. 3, pp. 93-101.
Abstract: Die Gefahrenzonenplanung in Hangbereichen sollte sich aur folgende Unterlagen stützen können:
- die geotechnische Ausscheidung der Locker- und Festgesteine.
- die Lokalisierung der vorhandenen Massenbewegungen nach Größe, Art und Form.
- die nähere Kennzeichnung der vorhandenen Massenbewegungen mit Hilfe eines Erhebungsbogens.
- die Karte der Hangneigung und der Vegetationsverteilung.
- die Gefahrenkarte im weiteren Sinn, das heißt die Angabe der möglichcn Massenbewegungen.
- die Gefahrenkarte im engeren Sinn, das heißt die Angabe der möglichen Massenbewegungen im Zusammenhang mit der Kennzeichnung der Gefahrenstufe.
Die seit den letzten Jahren vorgelegten Untersuchungen und Vorschläge zeigen, daß ein gewisses
Grundlagenmaterial erarbeitet worden ist, daß wir aber in der Realisierung solcher detaillierter
Kartierungen und Aufnahmcn noch am Anfang stehen.
Insbesondere wünschenswert wäre, bevor weitere Untersuchungen und Karten erstellt werden:
- die Terminologie der verwendeten Begriffe und die auf den Karten ausgeschiedenen Zeichen und Farbgebungen allgemein verbindlich festzulegen, so daß die von verschiedenen Autoren in verschiedenen Regionen erarbeiteten Karten und Unterlagen vergleichbar sind. So sollten die diskutierten Gefahrenkarten ähnlich den geologischen und in letzter Zeit auch den ingenieurgeologischen Karten ein einheitliches Gepräge aufweisen;
- die Ausarbeitung von Testsystemen, um bei minimalem Arbeitsaufwand eine einwandfreie, objektive und schlüssige Bewertung garantieren zu können;
- die Kontakte zur Praxis zu intensivieren, um die zum Teil rein wissenschaftlichen Zielsetzungen solcher Arbeiten mit den praktischen Bedürfnissen der Gefahrenzonenplanung in Einklang zu bringen.
Moser M (1971), "Zahl, Form, Vorgang und Ursache der Anbruchsbildung und ihre Beziehung zum geologischen Untergrund im Bereich des mittleren Leschtales (Kärnten)", In Proc. of the II International Congress Interpraevent 1971, Villach. Villach Vol. 1, pp. 35-48.
Abstract: Das Gailtal war von alters her bei Hochwasserkatastrophen ein Gebiet, das durch solche Elementarereignisse empfindliche Verluste an Kulturboden hinnehmen mußte. Durch die Gail selbst und deren Zubringer wurde an manchen Stellen die gesamte Talbreite von riesigen Schuttmengen eingenommen. Doch erst zu Ende des 19. Jhdt. wurde mit der vollständigen Regulierung der Gail, wenn man von kleineren Korrektionen in Ortsbereichen und Errichtung von Geschiebestausperren an Grabenausgängen absieht, begonnen. Diese Regulierungsarbeiten betrafen alle das eigentliche Gailtal (Gewässerstrecke von Kötschach/Mauthen bis Arnoldstein).
Moser M and Hohensinn F (1983), "Geotechnical Aspects of Soil Slips In Alpine Regions", Engineering Geology. Vol. 19(3), pp. 185-211. Elsevier Science Bv.
Abstract: Slope movements are due to many different causes. Numerous investigations carried out during the last ten years have led to the supposition that almost all slope movements, and particularly those occurring in soils, are conditioned by a significant combination of factors.
For the Alpine regions, quantity, duration and kind of precipitation have to be considered as direct mechanical causes. Combined with such contributing factors as geological and soil-mechanical properties, aspect, vegetation, slope inclination and slope morphology, they will determine the type, dimensions and process of slope movements.
The detailed investigation of 140 slope movements in slightly cohesive soils show that the process of movement is represented by sliding and flow events. In particular it was found out that shallow scars with planar slides predominate so that the supposition of an infinite slope model for slope stability appears to be justified. In many cases debris flows and debris avalanches continued downslope of the source area of the scars.
Mössmer E (1985), "Einflussfaktoren für die Blaikenerosion auf beweideten und aufgelassenen Almflächen im kalkalpinen Bereich der Landkreise Miesbach und Rosenheim"
Abstract: Ziel dieser Untersuchung war es, den Zusammenhang zwischen Blaikenerosion und Standortsfaktoren getrennt nach beweideten und aufgelassenen Almen differenziert zu analysieren. Dabei wurde besonderer Wert darauf gelegt, durch die Wahl eines Stichprobenverfahrens subjektive Einflüsse bei der Datenaufnahme soweit wie möglich auszuschalten und durch die Verwendung von multiplen Regressionsverfahren bei der Datenauswertung gegenseitige Einflüsse von Variablen zu berücksichtigen sowie eine Gewichtung der Faktoren bezüglich der Rangfolge ihres Einflusses auf die Blaikenerosion zu finden; beides ist bei rein deskriptiven und beobachtenden Verfahren nur sehr begrenzt moglich.
Mössmer E (1984), "Unterschiede der standörtlichen Einflussfaktoren auf die Blaikenerosion zwischen beweideten und aufgelassenen Alm", In Proc. of the V International Congress Interpraevent 1984, Villach. Vol. 3, pp. 79-88.
Abstract: Ziel der vorliegenden Untersuchung (Mössmer E., 1984) war es, den Zusammenhang zwischen Blaikenerosion und Standortsfaktoren getrennt nach beweideten und aufgelassenen Almen zu analysieren. Die Ergebnisse zeigen, daß der Blaikenflächenanteil bei genereller Betrachtung auf beweideten und aufgelassenen Almflächen mit 0.9 % bzw. 2,3 % zwar verhältnismäßig gering ausfällt, daß jedoch bei der Beurteilung der Blaikengefährdung von Almflächen nicht pauschal, sondern sehr differenziert und unter Einbeziehung der örtlichen Situation vorgegangen werden muß. Dabei stellte sich heraus, daß sich bestoßene und aufgelassene Almen deutlich unterscheiden. So ist auf bestimmten Flächen bei Einstellung der Weidenutzung mit einer verstärkten und früher einsetzenden Blaikenerosion zu rechnen, was dazu führt, dass der genannte Durchschnittswert hier weit überschritten wird. Aus landeskultureller Sicht gibt es auf solchen Flächen nur zwei Nutzungsmöglichkeiten, entweder die weitere Beweidung oder die Aufforstung.
Mouri G, Shiiba M, Hori T and Oki T (2011), "Modeling shallow landslides and river bed variation associated with extreme rainfall-runoff events in a granitoid mountainous forested catchment in Japan", Geomorphology., January, 2011. Vol. 125(2), pp. 282-292.
Abstract: In this study, we developed an algorithm to predict the long-term dynamic behavior of shallow landslides (<1.0 m depth) based on physical processes. Shallow landslides and rainfall-runoff processes from a mountain area were calculated using the kinematic wave method to quantify subsurface and surface water flow, calculate sediment yield, and conduct infinite-length slope stability analysis. Debris flow, bedload, suspended load, and wash load were considered in the proposed model. Moreover, we simulated the presence of dams and sand-erosion control devices in the stream channel using a non-uniform flow sub-model in which energy loss near a dam is expressed by an energy-conservation equation. Sand-erosion control is important to controlling the amount of sediment in a dam catchment and the stream channel. The proposed method was validated by applying it to the Yahagi Dam catchment in Japan. Comparison of observed and calculated landslides indicated that the model reproduces the general characteristics of sediment transport dynamics reasonably well. The results showed 7.0 million m(3) of total sediment inflow to the dam, 2.6 million m(3) (approximately 37% of the total sediment flux) of sediment deposition behind the dam, and 4.4 million m(3) (approximately 63% of total sediment flux) of sediment discharge (mostly wash load) from the dam. A survey measured 2.4 million m(3) of sediment deposition behind the dam, which compared to our calculated value of 2.6 million m(3) gives an error between simulated and observed values of 7%. (C) 2010 Elsevier B.V. All rights reserved.
Mueller R and Loew S (2009), "Predisposition and cause of the catastrophic landslides of August 2005 in Brienz (Switzerland)", Swiss Journal of Geosciences., September, 2009. Vol. 102(2), pp. 331-344.
Abstract: Very intensive rainfall in August 2005 (>300 mm/3 days) triggered moderately deep (2-10 m) landslides of about 50'000 m(3) volume each in two mountain torrent catchments above the village of Brienz (Berner Oberland, Switzerland). These landslides - originating in Trachtbach and Glyssibach catchments-transformed into extremely rapid (> 5 m/s) debris flows, which caused significant damage in inhabited areas; two persons lost their lives and about twenty-five families became homeless. The Brienz case was the most damaging one among many landslide disasters occurring during those rainy days in the Swiss Alps. In this paper we study in detail the predisposition and causes of the 2005 landslides in the Brienz area, based on field mapping, analysis of high resolution images and digital terrain models, derived from LIDAR and infrared measurements taken before and after the event. The features of these landslides are compared with past and dormant landslides in the mid-slope portion of the mountain chain north of Brienz, which has been the source of many catastrophic mass wasting events during the last centuries. Detailed field mapping shows that highly weathered series of strongly overconsolidated Mesozoic marls (Diphyoides Limestone & Vitznau Marls of Valanginian age) and their residual soils form the primary source for the sliding materials. The rupture surfaces of the moderately deep landslides often run at the transition from saprolite to weathered bedrock, with a dip angle of about 40 degrees in the landslide depletion area. These landslides transform into debris flows, where debris slides into strongly convergent hillslopes or directly into headwater channels. Weathering of the Valanginian Marls is very fast, leading to high frequency landsliding in areas where this formation is exposed or close to ground surface. As not all landslides transform into fast and long runout debris flows, colluvium from older landslides forms a second important material that becomes mobilized by heavy rainstorms. The depleted volume remaining today in the source areas of the Trachtbach and Glyssibach landslides amounts to about 30'000 m(3) each. These soil masses will be mobilized in future rainstorms. Mitigation actions have been implemented to reduce their damage potential in the Brienz area.
Muenchow J, Brenning A and Richter M (2012), "Geomorphic process rates of landslides along a humidity gradient in the tropical Andes", Geomorphology., February, 2012. Vol. 139, pp. 271-284.
Abstract: Areas with high landslide activity and diversity were encountered in the tropical Andes of Southern Ecuador under contrasting, semi-arid to perhumid climatic conditions. The objective of this study was to determine and compare geomorphic process rates of shallow landslides along this remarkable humidity gradient and subject to different types of human-made and natural environmental changes. Geomorphic work, geomorphic power and landslide mobilization rate (LMR) were therefore calculated for shallow landslides in two study areas with two separate geological or land use-related subareas each. While landslide ages were known in the perhumid Reserva Biologica San Francisco (RBSF) area, only an approximation of the frequency of critical landslide-triggering rainfall events was available for the semi-arid Masamanaca area. Landslide volumes were estimated by volume-area scaling. Generalized additive models (GAMs) were used as landslide susceptibility models in order to analyze the relative importance of topography, and to downscale LMR values to a fine spatial resolution. LMR in the perhumid RBSF area ranged from approximate to 2 mm yr(-1) in the natural part of this area with tropical mountain rainforests to approximate to 5 mm yr(-1) in the human-influenced part. The semi-arid Masamanaca area, though subject to greater estimation uncertainties, displayed LMR on the order of approximate to 0.4 to 4 mm yr(-1) for shallow landslides. The results provide a basis for the spatially differentiated assessment of landscape evolution and degradation in an area with a close relation between landslide activity, natural vegetation succession and human land use. (C) 2011 Elsevier B.V. All rights reserved.
Mulder VL, de Bruin S, Schaepman ME and Mayr TR (2011), "The use of remote sensing in soil and terrain mapping - A review", Geoderma., April, 2011. Vol. 162(1-2), pp. 1-19.
Abstract: This article reviews the use of optical and microwave remote sensing data for soil and terrain mapping with emphasis on applications at regional and coarser scales. Remote sensing is expected to offer possibilities for improving incomplete spatial and thematic coverage of current regional and global soil databases. Traditionally, remotely sensed imagery have been used to support segmentation of the landscape into rather homogeneous soil landscape units for which soil composition can be established by sampling. Soil properties have also been inferred from optical and microwave data using physically-based and empirical methods. Used as a secondary data source, remotely sensed imagery may support spatial interpolation of sparsely sampled soil property data. Soil properties that have been measured using remote or proximal sensing approaches include mineralogy, texture, soil iron, soil moisture, soil organic carbon, soil salinity and carbonate content. In sparsely vegetated areas, successful use of space borne, airborne, and in situ measurements using optical, passive and active microwave instruments has been reported. On the other hand, in densely vegetated areas, soil data acquisition typically relied on indirect retrievals using soil indicators, such as plant functional groups, productivity changes, and Ellenberg indicator values. Several forms of kriging, classification and regression tree analyses have been used jointly with remotely sensed data to predict soil properties at unvisited locations aiming at obtaining continuous area coverage. We expect that remotely sensed data from existing platforms and planned missions can provide an important data source supporting digital soil mapping. Yet, most studies so far have been performed on a local scale and only few on regional or smaller map scale. Although progress has been made, current methods and techniques still bear potential to further explore the full range of spectral, spatial and temporal properties of existing data sources. For example, space borne spectroscopy has been of limited use in retrieving soil data when compared to laboratory or field spectroscopy. To date, there is no coherent methodology established, where approaches of spatial segmentation, measurements of soil properties and interpolation using remotely sensed data are integrated in a holistic fashion to achieve complete area coverage. Such approaches will enhance the perspectives of using remotely sensed data for digital soil mapping. (C) 2011 Elsevier B.V. All rights reserved.
Nadim F, Kjekstad O, Peduzzi P, Herold C and Jaedicke C (2006), "Global landslide and avalanche hotspots", Landslides., May, 2006. Vol. 3(2), pp. 159-173.
Abstract: Allocating resources for natural hazard risk management has high priority in development banks and international agencies working in developing countries. Global hazard and risk maps for landslides and avalanches were developed to identify the most exposed countries. Based on the global datasets of climate, lithology, earthquake activity, and topography, areas with the highest hazard, or "hotspots", were identified. The applied model was based on classed values of all input data. The model output is a landslide and avalanche hazard index, which is globally scaled into nine levels. The model results were calibrated and validated in selected areas where good data on slide events exist. The results from the landslide and avalanche hazard model together with global population data were then used as input for the risk assessment. Regions with the highest risk can be found in Colombia, Tajikistan, India, and Nepal where the estimated number of people killed per year per 100 km(2) was found to be greater than one. The model made a reasonable prediction of the landslide hazard in 240 of 249 countries. More and better input data could improve the model further. Future work will focus on selected areas to study the applicability of the model on national and regional scales.
Nakamura H (2004), "Field instrumentation and laboratory investigation", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 541-548. Taylor & Francis.
Abstract: Recently, many new technologies have been introduced for investigation of landslide and mass movement phenomena. New technologies have made possible to interpret the landslide phenomena more clearly and at the same time it has provided new prospects for laboratory investigation. This paper will deal with some of these investigation techniques and their application as mentioned below.
a. Inspection of landslide using borehole televiewer (BHTV)
b. Jet foam boring method and its use for high quality sampling
c. Use of Optical fiber technique for landslide experiments and monitoring
d. Evaluation of slope stability using thermal infrared remote-sensing
e. Application of X-Ray CT scan for analyzing landslide borehole samples.
As an example, the high quality sampling technique using stiff-foam does not only provide better core samples, but the samples thus obtained can be used as undisturbed sample to determine physical properties of the landslide soil, such as cohesion and friction parameters and saturated and unsaturated conductivity etc.
Nearing MA, Simanton JR, Norton LD, Bulygin SJ and Stone J (1999), "Soil erosion by surface water flow on a stony, semiarid hillslope", Earth Surface Processes and Landforms., August, 1999. Vol. 24(8), pp. 677-686. John Wiley & Sons Ltd.
Abstract: Soil erosion on hillslopes occurs by processes of soil splash from raindrop impacts and sediment entrainment by surface water flows. This study investigates the process of soil erosion by surface water flow on a stony soil in a semiarid environment. A field experimental method was developed whereby erosion by concentrated flow could be measured in predefined flow areas without disturbing the soil surface. The method allowed for measurements in this study of flow erosion at a much wider range of slopes (2.6 to 30.1 per cent) and unit discharge rates (0.0007 to 0.007 m(2) s(-1)) than have been previously feasible. Flow velocities were correlated to discharge and hydraulic radius, but not to slope. The lack of correlation between velocity and slope might have been due to the greater rock cover on the steeper slopes which caused the surface to be hydraulically rougher and thus counteract the expected effect of slope on flow velocity. The detachment data illustrated limitations in applying a linear hydraulic shear stress model over the entire range of the data collected. Flow detachment rates were better correlated to a power function of either shear stress (r(2) = 0.51) or stream power (r(2) = 0.59). Published in 1999 by John Wiley & Sons, Ltd.
Neitsch S, Arnold J, Kiniry J and Williams J (2009), "Soil & Water Assessment Tool - Theoretical Documentation Version 2009"
Neuhaeuser B, Damm B and Terhorst B (2012), "GIS-based assessment of landslide susceptibility on the base of the Weights-of-Evidence model", Landslides., December, 2012. Vol. 9(4), pp. 511-528.
Abstract: The major scope of the study is the assessment of landslide susceptibility of Flysch areas including the Penninic Klippen in the Vienna Forest (Lower Austria) by means of Geographical Information System (GIS)-based modelling. A statistical/probabilistic method, referred to as Weights-of-Evidence (WofE), is applied in a GIS environment in order to derive quantitative spatial information on the predisposition to landslides. While previous research in this area concentrated on local geomorphological, pedological and slope stability analyses, the present study is carried out at a regional level. The results of the modelling emphasise the relevance of clay shale zones within the Flysch formations for the occurrence of landslides. Moreover, the distribution of mass movements is closely connected to the fault system and nappe boundaries. An increased frequency of landslides is observed in the proximity to drainage lines, which can change to torrential conditions after heavy rainfall. Furthermore, landslide susceptibility is enhanced on N-W facing slopes, which are exposed to the prevailing direction of wind and rainfall. Both of the latter geofactors indirectly show the major importance of the hydrological conditions, in particular, of precipitation and surface runoff, for the occurrence of mass movements in the study area. Model performance was checked with an independent validation set of landslides, which are not used in the model. An area of 15% of the susceptibility map, classified as highly susceptible, "predicted" 40% of the landslides.
Neuhaeuser B and Terhorst B (2009), "Assessment of the Landslide Susceptibility at the Jurassic Escarpment of the Swabian Alb by Means of GIS-based Statistical-probabilistic Evaluation.", Photogrammetrie Fernerkundung Geoinformation. Vol. 2(2), pp. 143-160.
Abstract: Assessment of the Landslide Susceptibility at the Jurassic Escarpment of the Swabian Alb by Means of GIS-based Statistical-probabilistic Evaluation. GIS-based model for the assessment of the landslide susceptibility in a selected area of the Jurassic escarpment in the Swabian Alb (SW-Germany) is described. The statistical-probabilistic method called "Weights-of-Evidence" originally developed for the explorative mineralogy - is used for the assessment of the landslide hazard. A quantitative model is applied to the known landslides and their causative factors and is finally visualised in susceptibility maps. While previous research work in this area concentrated oil large-scale investigations, the present study was carried out at a regional level with a target scale of 1 : 150,000. Potential susceptible areas can be delineated and landslide indicators can be identified from the available data set. The produced maps cover a distance of up to 12 kin of the Jurassic escarpment, showing five classes of landslide susceptibility.
Neuhaeuser B and Terhorst B (2007), "Landslide susceptibility assessment using "weights-of-evidence" applied to a study area at the Jurassic escarpment (SW-Germany)", Geomorphology., April, 2007. Vol. 86(1-2), pp. 12-24.
Abstract: A GIS-based model for the assessment of the landslide susceptibility in a selected area of the Jurassic escarpment in the Swabian A1b (SW-Germany) is described, using the weights-of-evidence method. A quantitative model applied to landslides and their causative factors was created and illustrated in susceptibility maps. While previous research work in this area concentrated on large-scale investigations, the present study was carried out at a regional level with a target scale of 1: 150,000. The method is based on the assumption that future landslides will occur under the conditions similar or equal to those of past comparable landslides of the same type. Therefore the analysis was limited to one single type of landslides where the causative factors can be assumed as stable over a period of time. Due to uncertainties in the model, mainly because of variances of the weights assigned to the causative factors, the derived probability values, representing the susceptibility for future landslides, have to be considered relative. However, potential susceptible areas can be delineated and landslide indicators can be identified from the available data set. Slopes with angles from 11 degrees to 26 degrees, composed of the Oxford limestone/marls as well as strongly argillaceous and silty colluvial material such as solifluction layers and colluvial cones, are susceptible. The main soil type of the escarpment and the other steep slopes of the Swabian A1b valleys are Rendzinas formed in solifluction layers. Rendzina profiles including rock debris and clay, which are superimposed on marl debris, were also identified as landslide indicators. These findings are in agreement with previous geomorphological studies in the same area. The methodology seems to have widespread applicability beyond this local research area, with the limitation that the knowledge of past landslides input to the model affects the absolute value of the final probability. (c) 2006 Elsevier B.V. All rights reserved.
Newesely C, Mader-Oberhammer M, Raffeiner G, Porzelt M and Cernusca A (2004), "Bewirtschaftungsbedingte Veränderungen im Gebietswasserhaushalt alpiner Ökosysteme", Landwirtschaft und Grundwasserschutz 2004. , pp. 57-62.
Abstract: Ziel der im Rahmen des EU INTERREG II - Programms durchgeführten Untersuchungen war es, die Auswirkungen der Bewirtschaftungsänderung von Almflächen auf den Wasserhaushalt zu untersuchen. Dafür wurden auf je einer Mähwiese, einer Weide sowie im brachgefallenen Gelände Messplots eingerichtet, auf denen die Evapotranspiration mittels wiegender Lysimeter gemessen wurde. Der Oberflächenabfluss wurde mittels Beregnungsexperiment auf 12 repräsentativen Stellen im gesamten Almgelände ermittelt. Die Untersuchungen haben gezeigt, daß die evapotranspiration auf Weideflächen deutlich niedriger ist als auf Mähwiesen bzw. auf krautreichen Brachflächen. Das bedeutet eine Erhöhung der Wasserabgabe in das Gebiet entwässernden Bachlauf. Der Oberflächenabfluss war nur auf Weideflächen die erst seit wenigen Jahren durch die Umwandlung von Mähwiesen gewonnen wurden deutlich messbar. Auf diesen "jungen Weiden" lag der Abfluss aber bei über 18% der Beregnungsintensität. Das großflächige Umwandeln von Mähwiesen in Weiden kann bei Starkregenereignissen zu einer deutlichen Erhöhung des oberflächlich abfließenden Wassers führen.
Newesely C, Tasser E, Spadinger P and Cernusca A (2000), "Effects of land-use changes on snow gliding processes in alpine ecosystems ", Basic and Applied Ecology . Vol. 1(1), pp. 61 - 67.
Abstract: The reduction of agricultural use of alpine ecosystems went hand in hand with an increase of soil erosion in many areas. A possible reason for this phenomenon is the more frequent snow gliding in winter. In a large research program (part of the ECOMONT project) managed areas, as well as areas that are not used or only used to some extent, were investigated in order to find out their liability to snow gliding. By means of statistical methods, a model was designed that shall explain the influence of terrain parameters (slope inclination, exposition, altitude) as well as the influence of the management. The investigations have shown that the liability of alpine ecosystems to snow gliding increases with the reduction of agricultural use. Especially high gliding rates were observed on low soft dwarf shrubs canopies. Bigger dwarf shrubs or trees are obstacles and stabilize the snow cover so that the gliding rates decrease drastically.
Ng C, Springman S and Alonso E (2009), "Monitoring the Performance of Unsaturated Soil Slopes", In Laboratory and Field Testing of Unsaturated Soils. , pp. 187-204. Springer Netherlands.
Abstract: Field monitoring is necessary for the geotechnical engineer to verify design assumptions. More importantly, the field data may also be assembled into a comprehensive case record that is available for use when checking validity of any analytical and numerical models. The ongoing process of back-analysis in unsaturated soil engineering can help to refine and improve our understanding, providing guidance for future designs, where the effects of soil suction and hydraulic hysteresis are still being explored. A range of recent field studies of the mechanisms of rainfall infiltration into slopes is presented. In addition, some physical simulations of unsaturated soil slopes subjected to rainfall, rising ground water table and changes of moisture in centrifuge model tests are reported.
Nichol J and Wong MS (2005), "Satellite remote sensing for detailed landslide inventories using change detection and image fusion", International Journal of Remote Sensing., May, 2005. Vol. 26(9), pp. 1913-1926.
Abstract: The availability of high spatial and spectral resolution remote sensing systems may be accompanied by changes in techniques for applying the data if appropriate data processing methodologies can be demonstrated. Landslide monitoring, which requires large areas to be surveyed at a detailed level, has previously been unsatisfactory due to its reliance on air photograph interpretation. This study demonstrates the synergistic use of medium resolution, ;multitemporal Satellite pour l'Observation de la Terre (SPOT) XS, and fine resolution IKONOS images for landslide inventories. The post-classification comparison method of change detection using the Maximum Likelihood classifier with SPOT XS images was able to detect approximately 70% of landslides, the main omissions being those smaller than approximately half a pixel wide. The visual quality of images obtained from Pan-sharpening of IKONOS images was comparable to that obtainable from 1 : 10 000 scale air photographs, enabling detailed interpretation of landslides and associated environmental features. A methodology combining the two levels of survey is proposed for regional scale landslide monitoring.
Niedrist G, Tasser E, Lueth C, Dalla Via J and Tappeiner U (2009), "Plant diversity declines with recent land use changes in European Alps", Plant Ecology., June, 2009. Vol. 202(2), pp. 195-210.
Abstract: Against a background of increasing land use intensification on favorable agricultural areas and land abandonment on less arable areas in the Alps, the aim of this investigation was to detect whether and how 10 differently used types of grassland can be distinguished by site factors, plant species composition, and biodiversity. By using a very large number of vegetation surveys (936) that were widely distributed in the Central Alps, site parameters and species composition of the different land use types were compared by discriminant analyses and various biodiversity indices. Results showed that land use is a significant factor affecting the development of different grassland communities with site factors playing a subordinate, yet important role. The 10 land use types studied can be clearly differentiated from one another by single species as well as by species composition. Our study found that the number of plant communities along with the number of species decreases constantly and significantly with increasing land use intensity and on abandoned land. For example, on average, extensively used meadows have more than three times as many species as intensively used meadows. Further, the most even distribution of species (Evenness index) is reached in intensively used meadows, whereas on pastures and abandoned land, some species become dominant forcing other species to recede. The results confirm that due to current trends in agriculture, such as land abandonment and land use intensification, plant diversity in the Alps is decreasing considerably.
Niehoff D (2001), "Modellierung des Einflusses der Landnutzung auf die Hochwasserentstehung in der Mesoskala". Thesis at: University of Potsdam.
Abstract: Since 1990, several of the large European river basins were affected repeatedly by extreme floods. As both the landscape and the river systems in large parts of Central Europe have undergone major changes in the past, during the search for the causes of this accumulation of extreme events also the impact of human activities on flooding has been discussed. River training, surface sealing, intensive agricultural land-use, consolidation of farmland, and damages to forests are only some examples and consequences of the anthropogenic interferences with the landscape. But due to the diversity of the processes and factors involved, by now it can only be estimated how far the flood situation has changed by these interferences.
Therefore, the main target of this thesis is to describe systematically in which way, to what extent and under which circumstances the land-use exerts an influence on storm-runoff generation and subsequently the discharge of rivers.
This is investigated by means of exemplary model applications at the hydrological meso-scale. For this task, the deterministic and distributed hydrological model wasim-eth was chosen due to its well-balanced mixture of physically-based and conceptual approaches. In the framework of this thesis, the model has been extended in order to cope with several phenomena which are important when aiming at a characterization of the influence of land-use on flood generation: (1) Preferential flow in macropores is treated by a division of the soil into macropores and a soil matrix. This so-called double-porosity approach allows for fast infiltration and percolation beyond the hydraulic conductivity of the soil matrix. (2) Siltation expresses itself within the model as a deterioration of infiltration conditions at the soil surface, depending on precipitation intensity and the degree of vegetation covering. (3) The heterogeneous appearance of built-up areas, consisting of both sealed areas and pervious areas, is taken into account by dividing each partial area into an unsealed part and a sealed part which is connected to the sewer system. (4) Decentralized storage can be simulated for natural depressions as well as for specific infiltration measures with defined infiltration conditions.
The extended model is exemplarily applied to three meso-scale tributaries of the Rhine river. These three catchments with an area of between 100 and 500 km² were chosen with regard to their prevailing land-use, one of them being heavily urbanized, one dominated by agricultural use, and one being mainly forested.
For these three catchments, spatially explicit land-use and land-cover scenarios were developed. The impact of these scenarios on storm-runoff generation is being simulated using the extended hydrological model. In this context, namely urbanization, infiltration measures in settlement areas, conversion of farmland to set-aside areas, altered agricultural management practices, affor estation and storm damages in forests are taken into account.
These changes influence the interception of rainfall, its infiltration into the soil, the subsurface flow processes next to the soil surface as well as, for example in the case of sewer systems, also runoff concentration.
The hydrological simulations demonstrate that sealing of the soil surface is the most intensive intervention in the natural conditions among the ones which are mentioned above. Therefore it results in the strongest (negative) changes of the flooding situation in a catchment. In addition to that, the simulations show that a simple alteration in the interception capacity does not yield significant changes in catchment response, because the storage capacity of vegetation surfaces is rather low compared to the volume of storm events which normally lead to significant floods. More pronounced changes arise from modifications in the infiltration conditions.
The limits of the methodology which was chosen for this thesis become obvious when simulating altered agricultural management practices. Due the complexity of the processes involved, mathematical description and parameterization is difficult and therefore afflicted with high uncertainty.
In addition to that, the modelling results prove that global statements on the influence of land-use on flood generation are illegitimate because of the paramount importance of the climatic and physiographic boundary conditions. Climatic boundary conditions are precipitation intensity and duration as well as the moisture conditions before a storm event. The physiographic boundary counditions are given by the geomorphological and geological catchment properties. Furthermore, with increasing scale there is a shift in the relative importance of the different types of rainfall as well as the different geophysical catchment properties. Therefore, the spatial and temporal scale for which the results are valid have to be clearly defined. This is taken into account consequently within this thesis – in contrast to many other studies on this topic.
Depending on boundary conditions and spatial scale, the findings allow the following statements regarding the influence of land-use changes on storm-runoff generation:
(1) For intensive convective storm events with generally low antecedent soil moisture, the influence of land-use is greater than for long-lasting advective storm events with low rainfall intensities, because in the first case changes in the infiltration conditions are more important than during times of low precipitation intensities.
(2) In small catchments, where small-scale convective cells can lead to a flood, the influence of land-use is accordingly greater than in large river basins like the Rhine basin, where long-lasting advective rainfalls (possibly in combination with snowmelt) are relevant.
(3) In areas with good storage conditions like thick, permeable soils and pervious rock underneath, the influence of land-use is greater than in areas with thin soils and only slightly permeable bedrock. This is due to the fact that in case of deteriorating infiltration conditions, more storage space for precipitation is lost in areas with good storage conditions than in other areas.
Nilaweera NS and Nutalaya P (1999), "Role of tree roots in slope stabilisation", Bulletin of Engineering Geology and the Environment. Vol. 57(4), pp. 337-342. Springer-Verlag.
Abstract: The mechanical stabilisation of soil slopes by means of tree roots depends largely on the strength properties of the roots and their growth pattern within the soil. In particular areas, the selection of indigenous tree species on the basis of their root properties is an essential part of biotechnical slope protection. In order to determine the effects of tree roots on slope stabilisation in the mountainous area of Khao Luang, southern Thailand, seven tree species were studied. The distribution and penetration of the roots was established and their tensile strength and pull-out resistance determined. The paper evaluates the potential contribution of each of these species to slope stabilisation with reference to existing slope conditions.
O'Loughlin EM (1986), "Prediction of Surface Saturation Zones in Natural Catchments by Topographic Analysis", Water Resources Research. Vol. 22(5), pp. 794-804.
Abstract: The topography of hillslopes or whole catchments is analyzed numerically to calculate local geometric and drainage attributes that can be combined to test for the expectation of soil waterlogging. At locations where accumulated drainage flux from upslope exceeds the product of soil transmissivity and the local slope, saturation to the soil surface occurs. Results of the analysis of specific landscapes are presented as a location dependent function. The function may be mapped as isolines to define successive boundaries of zones of soil saturation, depending on the wetness state of the landscape as a whole. The analysis is applied to two catchments, to predict the growth or contraction of zones of waterlogging for a range of drainage fluxes and to simulate the effects of transpiration changes in part or all of the catchment. In the second application, the predicted boundaries of saturated zones are used to calculate the minimum proportion of a catchment's area that produces rapid surface runoff. This proportion is shown to depend on the value of a normalized wetness parameter. Storm runoff data support the predicted form of the relationship.
Oberhauser R (1998), "Erläuterungen zur geologisch-tektonischen Übersichtskarte von Vorarlberg 1: 200.000" Geologische Bundesanstalt, Wien..
Oberhauser R (1984), "Bericht 1983 über geologische Aufnahmen im Helvetikum und der nördlichen Flyschzone auf Blatt 111 Dornbirn", Jb. Geol. B.-A. Wien. Vol. 127, pp. 226-229.
Oddsson B (1996), "Instabile Hänge und andere risikorelevante natürliche Prozesse: Nachdiplomkurs in angewandten Erdwissenschaften" Springer DE.
Oh H-J and Pradhan B (2011), "Application of a neuro-fuzzy model to landslide-susceptibility mapping for shallow landslides in a tropical hilly area", Computers & Geosciences., September, 2011. Vol. 37(9), pp. 1264-1276.
Abstract: This paper presents landslide-susceptibility mapping using an adaptive neuro-fuzzy inference system (ANFIS) using a geographic information system (GIS) environment. In the first stage, landslide locations from the study area were identified by interpreting aerial photographs and supported by an extensive field survey. In the second stage, landslide-related conditioning factors such as altitude, slope angle, plan curvature, distance to drainage, distance to road, soil texture and stream power index (SPI) were extracted from the topographic and soil maps. Then, landslide-susceptible areas were analyzed by the ANFIS approach and mapped using landslide-conditioning factors. In particular, various membership functions (MFs) were applied for the landslide-susceptibility mapping and their results were compared with the field-verified landslide locations. Additionally, the receiver operating characteristics (ROC) curve for all landslide susceptibility maps were drawn and the areas under curve values were calculated. The ROC curve technique is based on the plotting of model sensitivity - true positive fraction values calculated for different threshold values, versus model specificity - true negative fraction values, on a graph. Landslide test locations that were not used during the ANFIS modeling purpose were used to validate the landslide susceptibility maps. The validation results revealed that the susceptibility maps constructed by the ANFIS predictive models using triangular, trapezoidal, generalized bell and polynomial MFs produced reasonable results (84.39%), which can be used for preliminary land-use planning. Finally, the authors concluded that ANFIS is a very useful and an effective tool in regional landslide susceptibility assessment. (C) 2011 Elsevier Ltd. All rights reserved.
Ojeda-Moncayo J, Locat J, Couture R and Leroueil S (2004), "The magnitude of landslides: an overview", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 379-384. Taylor & Francis.
Abstract: The magnitude of a landslide is one of the most important characteristic to be considered at the time of a hazard assessment. Surprisingly, so far there is not a satisfactory expression of landslide magnitude that depicts not only the greatness of the phenomenon but its capacity to do damage whether for a past or potential mass movement. The paper presents the initial steps towards to establishing a comprehensive scale of landslides magnitude taking into account those several parameters that influence greatness and damage power of a landslide. Each parameter is briefly discussed and an approach for a landslide magnitude scale is given using simulated values.
Olalla C (2004), "Recent developments in landslide monitoring", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 1, pp. 549-555. Taylor & Francis.
Abstract: A general and brief overview of the different methods available for landslide instability monitoring is given.The main objetive is to provide engineers and geologists with the most recent tools that can be used for field instrumentation, rather than giving an account of the real state-of-the-art in this particular field.
It must be born in mind that always, among other data,
– a good topographic survey,
– a detailed geology,
– the evolution of the materials with depth, and
– the groundwater conditions, are needed.
Oliver M, Webster R and Gerrard J (1989), "Geostatistics In Physical-geography .1. Theory", Transactions of the Institute of British Geographers. Vol. 14(3), pp. 259-269.
Abstract: Geostatistics grew from meteorologists' desire to interpolate weather characteristics from sparse data and from mining engineers who wanted to estimate quantities of minerals in bodies of rock from drill cores. In both cases the properties of interest behaved as spatially correlated random variables. Practice in mining is now underpinned by sound theory, the theory of regionalized variables. It is widely recognized that the theory is properly applicable in many other branches of earth, atmospheric and marine science.
Part I of this paper reviews the more elementary aspects of the theory and its assumptions. It describes the method of local estimation embodied in regionalized variable theory known as kriging. The central tool of geostatistics is the variogram. which expresses quantitatively and succinctly spatially correlated variation, and its estimation is described. The more common forms of variogram are illustrated. and authorized models for them are listed. There are sound procedures for choosing and fitting models to variograms now using well-tried computer programs such as MLP and Genstat. Regionalized variable theory provides geographers with a concise and coherent methodology for describing and analysing spatially distributed data.
Omura H (1984), "Resistance index map of quick shallow landslide", In Proc. of the V International Congress Interpraevent 1984, Villach. Villach Vol. 2, pp. 159-166.
Opp C (1984), "Zur Entwicklung und Systematisierung der Catena-Konzeption", Hercynia N.F.. Vol. 2, pp. 204-217.
Abstract: Seit knapp 50 Jahren wird der Terminus Catena in den Geowissenschaften verwendet. Das Wort "Catena" stammt aus dem Lateinischen und ist am besten mit "Kette" zu übersetzen. Bodenkundler und Vertreter der Physischen Geographie verwenden diesen Begriff zur Bezeichnung räumlicher lateraler Boden- und/oder Landschaftsabfolgen bzw. zur Beschreibung und Darstellung des räumlichen, lateralen Wandels pedologischer und/oder landschaftlicher Merkmale.
Ostendorf B, Hilbert D, Köstner B, Tappeiner U and Tasser E (1999), "Toward a predictive understanding of ecosystem processes at the scale of landscapes", In International Congress on Modelling and Simulation Proceedings, vol. 3. The Modelling and Simulation Society of Australian and New Zealand. , pp. 685–690.
Abstract: In this paper we stress the importance of considering patterns at the regional-scale in global change studies. Ultimately, the assessment of how ecosystems processes (e.g. water and carbon fluxes) respond to future changes relies on plot level process studies. However, logistics or limited resources restrict the direct estimation of processes at larger spatial scales. Describing examples from studies in four different biomes, we show how process-level studies may be integrated with information gained from spatial analyses and outline the need to consider the spatial variability of environmental conditions to make realistic estimates for larger regions. We conclude that understanding the underlying causes of spatial patterns is essential for assessing the response of ecosystems to climate change. Vegetation models can be used to identify those driving variables that are likely to dominate the future responses of the ecosystem.
Otto JC and Dikau R (2004), "Geomorphologic system analysis of a high mountain valley in the Swiss Alps", Zeitschrift für Geomorphologie., September, 2004. Vol. 48(3), pp. 323-341.
Abstract: Geomorphologic processes in alpine environments are often reinforced compared to other systems as steep slopes, high relief, and highly variable climatic conditions increase process intensity. We discuss the geomorphologic system of a high alpine valley in Switzerland based on a detailed geomorphologic map at a scale of 1:25,000. The map displays the distribution of surface materials, geomorphologic landforms, and processes in the Turtmann valley, Valais, Switzerland, a southern tributary of the Rhone valley. The constitution of landform elements is employed to construct a qualitative model of the sediment transfer in the valley's system. We distinguish four subsystems that represent different geomorphologic conditions. Process coupling, sediment cascades, and paths of sediment transport are discussed for the subsystems. Although periglacial and glacial processes strongly influence the sediment movement in the hanging valleys, they do not affect the sediment output of the subsystems, due to climatic and surface structure conditions. While coarse debris is stored inside the hanging valleys, sediment output from the Turtmann valley system mainly consists of fine debris, which is transported by fluvioglacial processes. We are convinced that geomorphologic mapping represents a key tool for geomorphic system analysis, and serves as a basis for the development of sediment budget models.
Ouimet WB (2011), "TECTONIC GEOMORPHOLOGY The hills came tumbling down", Nature Geoscience., July, 2011. Vol. 4(7), pp. 424-425. Nature Publishing Group.
Pack RT and Goodwin CN (1997), "SINMAP User's Manual"
Pack RT, Tarboton DG and Goodwin CN (2005), "SINMAP 2.0-A Stability Index Approach to Terrain Stability Hazard Mapping, User's Manual."
Pack RT, Tarboton DG and Goodwin CN (1998), "The SINMAP approach to terrain stability mapping", In Proceedings fo the Eighth International Congress International Association For Engineering Geology and the Environment. Vancouver, Canada, SEP 21-25, 1998, 1998. , pp. 1157-1165. A A Balkema Publishers.
Abstract: A promising approach to modeling the spatial distribution of shallow debris slides combines a mechanistic infinite slope stability model with a steady-state hydrology model. The spatial distribution of a "stability index" is governed primarily by specific catchment area (the upslope area per unit contour length) and slope. The model can be interactively calibrated to the unique characteristics of the topography, rainfall, and soils of a particular study area using simple parameters, graphs and maps. once a landslide and terrain inventory is completed using aerial photographs, this approach is shown to have the capability of producing a stability classification map of a huge area in a very short time. An analysis of the Kilpala watershed of northern Vancouver Island, British Columbia is presented as an example.
Panek T, Brazdil R, Klimes J, Smolkova V, Hradecky J and Zahradnicek P (2011), "Rainfall-induced landslide event of May 2010 in the eastern part of the Czech Republic", Landslides., December, 2011. Vol. 8(4), pp. 507-516.
Abstract: More than 150 landslides originated in the eastern part of the Czech Republic (region of the Flysch Outer Western Carpathians-hereinafter, OWC) due to soil saturation caused by antecedent precipitation and long lasting and intensive rainfalls on 16-18 May 2010 (> 300 mm as measured by some stations). As a consequence, a multitude of small failures originated 88% of which was smaller than 10(4) m(2). Most landslides are characterised as shallow (< 10 m) or middle-deep (10-30 m) incipient (rather short travel) landslides, debris slides and soil slips spatially clustered to a geological domain underlain by rather weak thin-bedded flysch and unconsolidated Quaternary deposits. An exception to this is represented by a kilometre-long rockslide (similar to 2-3 mil m(3)) affecting tectonically weakened and weathered claystone/mudstone-dominated flysch on the southern slope of Mt. Girova (the Beskydy Mountains). The rockslide is one of the largest long runout landslides in the territory of the Czech Republic activated over the past few decades as it reaches the dimensions of the largest documented Holocene long runout landslides in the Czech part of the OWC. A majority of the May 2010 landslide events developed inside older (Holocene or historic) landslide terrains, which points to their spatial persistency and recurrent nature. In spite of the fact that the May 2010 landslide event was not as destructive as some previous landslide activisation in the OWC region (e.g. July 1997 event), it left many slope failures at the initial stage of their potential future reactivation.
Parise M (2001), "Landslide mapping techniques and their use in the assessment of the landslide hazard", Physics and Chemistry of the Earth Part C-solar-terrestial and Planetary Science. Vol. 26(9), pp. European Geophys Soc.
Abstract: Different types of maps depicting spatial distribution and activity of landslides are discussed in this paper. Analysis of the existing literature on the topic helped to point out advantages and drawbacks of each type of map, and their possible use for the assessment of the landslide hazard. Utility of the landslide map,, was also illustrated by mean,, of the results achieved for a real case study in Southern Italy, that highlighted in particular the good amount of information provided by landslide activity rnaps. (C) 2001 Elsevier Science Ltd, All rights reserved.
Park HJ, Lee JH and Woo I (2013), "Assessment of rainfall-induced shallow landslide susceptibility using a GIS-based probabilistic approach", Engineering Geology., July, 2013. Vol. 161, pp. 1-15.
Abstract: This study proposes a probabilistic analysis method to assess shallow landslide susceptibility over an extensive area by integrating an infinite slope model with GIS (Geographic Information System) and Monte Carlo simulation, taking into consideration the inherent uncertainty and variability in input parameters. The mechanical parameters of soil materials (such as cohesion and friction angle) used in the infinite slope analysis have been identified as the major source of uncertainty because of their spatial variability; therefore, these parameters were considered as random variables in this probabilistic landslide analysis. To properly account for the uncertainty in input parameters, the probabilistic analysis method used was Monte Carlo simulation. The process was carried out in a GIS-based environment because GIS has effective spatial data-processing capacity over broad areas. In addition, the hydrogeological model was coupled with the infinite slope model to evaluate increases in pore water pressure caused by rainfall. The proposed approach was applied to a practical example to evaluate its feasibility. The landslide inventory map and the spatial database for input parameters were constructed in a grid-based GIS environment and a probabilistic analysis was implemented using Monte Carlo simulation. To evaluate the performance of the model, the results of the probabilistic landslide susceptibility analysis were compared with the landslide inventory. The probabilistic approach demonstrated good predictive performance when compared with the landslide occurrence location. In addition, deterministic analysis was carried out using fixed single-input data for comparison with the results from the proposed approach. In this comparison, the probabilistic analysis showed better performance than the deterministic analysis. In addition, the results showed that proper consideration and understanding of uncertainties play an important role in accurately predicting shallow landslide susceptibility. (C) 2013 Elsevier B.V. All rights reserved.
Pellenq J, Kalma J, Boulet G, Saulnier G-M, Wooldridge S, Kerr Y and Chehbouni A (2003), "A disaggregation scheme for soil moisture based on topography
and soil depth"
, Journal of Hydrology. Vol. 276, pp. 112-127.
Abstract: This paper reports on a new soil moisture disaggregation scheme based on topography and soil depth information. It is designed for low resolution remote sensing data assimilation into hydrological modelling. The scheme makes use of a simple Soil Vegetation Atmosphere Transfer model coupled to the TOPMODEL formalism. Water and energy balance are computed at the catchment scale, taking lateral flows due to topography into account. Lumped values of near-surface and deep soil water content are then disaggregated at local scale using simple relationship between mean quantities, local topography and soil depth information. Results for a small water catchment in South-eastern Australia show satisfactory reproduction of the local soil moisture patterns using a combination of topography and soil depth information. Due to subgrid variability and differences between the simulation and observation scale (the Digital Elevation Model pixel versus the point measurement), the point-to-point comparison between observations and simulations shows a poor correlation. Rescaling shows that a good correlation is obtained when averaging the simulated and observed soil moisture over a length of 100 m.
Review: Hier werden Daten zur Bodenmächtigkeit zusammen mit Daten zur Topographie (Morphologie?) verwendet um Rückschlüsse auf die Bodenfeute zu machen.
Pentney RM and Dickson ME (2012), "Digital Grain Size Analysis of a Mixed Sand and Gravel Beach", Journal of Coastal Research. Vol. 28(1), pp. 196-201. The Coastal Education and Research Foundation 1656 Cypress Row Drive, West Palm Beach, FL 33411, USA.
Abstract: A new technique to estimate the properties of sediment from digital images is investigated. Sediment was obtained from mixed sand and gravel beaches in Hawke Bay, New Zealand. Samples were manually sieved, and grain size distributions were compared to those obtained from digital images. Digital image analysis provided variable estimates of the grain size distribution (R2 5 0.2120.74), with much poorer estimates obtained when images contained grain sizes beyond the range of sediments imaged for the calibration catalogue. A reasonable approximation of the mean grain size of a sample was returned from digital analyses when compared with the mean grain size obtained from sieving (R2 5 0.68), provided all sediment sizes within images fitted within the calibration catalogue. This paper discusses limitations of the technique when applied to mixed sand and gravel beaches, and possibilities for overcoming these (e.g., increasing sampling quantity). It is clear that a deeper understanding of the morphodynamics of mixed sand and gravel beaches requires methods capable of detailing the dynamic fluctuations of grain assemblages. Digital image analysis provides a very promising alternative to laborious and time-consuming manual sieving, and it is hoped that this paper provides a useful additional data set to help in the further refinement of methods for digital image analysis.
Perla R, Cheng TT and Mcclung DM (1980), "A 2-parameter Model of Snow-avalanche Motion", Journal of Glaciology. Vol. 26(94), pp. 197-207.
Abstract: Voellmy's (1955) method for computing the run-out distance of a snow avalanche includes an unsatisfactory feature: the a priori selection of a midslope reference where the avalanche is assumed to begin decelerating from a computed steady velocity. There is no objective criterion for selecting this reference, and yet the choice critically determines the computed stopping position of the avalanche. As an alternative, a differential equation is derived in this paper on the premise that the only logical reference is the starting position of the avalanche. The equation is solved numerically for paths of complex geometry. Solutions are based on two parameters: a coefficient offriction fL; and a ratio of avalanche mass-to-drag, MID. These are analogous to the two parameters in Voellmy's model, fL and tH. Velocity and run-out distance data are needed to estimate fL and MID to useful precision. The mathematical properties of two-parameter models are explored, and it is shown that some difficulties arise since similar results are predicted by dissimilar pairs of fL and MID.
Peruccacci S, Brunetti MT, Luciani S, Vennari C and Guzzetti F (2012), "Lithological and seasonal control on rainfall thresholds for the possible initiation of landslides in central Italy", Geomorphology., February, 2012. Vol. 139, pp. 79-90.
Abstract: We compiled a catalogue of 442 rainfall events with landslides in the Abruzzo, Marche, and Umbria regions, central Italy, between February 2002 and August 2010. For each event, we determined the duration D (in hours) and the cumulated (total) event rainfall E (in mm), using rainfall measurements obtained from a dense network of 150 rain gauges. Landslides were mapped as single points using Google Earth, and were attributed a level of mapping accuracy P, in four classes (P-1<1 km(2), P-10:,<10 km(2), P-100< 100 km(2). P-300<300 km(2)). Using this information, we determined cumulated event rainfall-rainfall duration (ED) thresholds, which are entirely equivalent to rainfall intensity-duration (ID) thresholds, and avoid unnecessary conversions. To determine the ED thresholds, we modified a statistical method first proposed to determine ID thresholds. Adopting a bootstrapping statistical technique, we expanded the method to determine the uncertainty associated with the parameters that define the power law threshold model, and the sensitivity of the thresholds to the number of (D,E) data points in the empirical data set. We determined ED thresholds for 1% and 5% exceedance probability levels: (i) for the entire study area, and for the three individual regions in the study area (Abruzzo, Marche, and Umbria); (ii) for three main lithological domains in the study area (post-orogenic sediments, flysch deposits, carbonate rocks); and (iii) for two seasonal periods (May-September, October-April). Comparison of the ED thresholds indicates that the cumulated amount of rainfall necessary to trigger landslides in flysch deposits is larger than in postorogenic sediments and carbonate rocks. However, the ED thresholds for post-orogenic sediments and carbonate rocks were statistically indistinguishable in the study area. Also, the seasonal thresholds were statistically different for rainfall durations shorter than 12 h and longer than 100 h, but were indistinguishable in the range 12
Perumpral JV (1987), "Cone Penetrometer Applications - A Review", Transactions of the Asae., July, 1987. Vol. 30(4), pp. 939-944.
Abstract: This report provides a history of cone penetrometers, a description of the various types, an explanation of the factors affecting the penetration resistance and a discussion of possible applications of cone penetrometers.
Petschko (2008), "Räumliche Analyse von gravitativen Massenbewegungen mittels multivariater Statistik". Thesis at: University of Vienna.
Abstract: Im August 2005 sind nach intensiven Regenfällen in der Region Gasen und Haslau in der Oststeiermark, mehr als 500 gravitative Massenbewegungen (auf 60 km²) aufgetreten, die hohe ökonomische Schäden verursachten und auch 2 Todesopfer forderten. Nach diesen Ereignissen wurde eine umfassende Kartierung der gravitativen Massenbewegungen von der Geologischen Bundesanstalt (GBA) durchgeführt. Diese Daten dienen als wichtige Grundlage für die vorliegende Analyse und wurden für diesen Zweck im Rahmen einer Kooperation der Arbeitsgruppe für Geomorphologische Systeme und Risikoforschung des Instituts für Geographie und Regionalforschung der Universität Wien mit der Abteilung für Ingenieurgeologie der Geologischen Bundesanstalt zur Verfügung gestellt. Das Ziel der vorliegenden Analyse war, eine Gefahrenhinweiskarte für die Region Gasen und Haslau bezüglich möglicher Anrisse von gravitativen Massenbewegungen zu erstellen und eine Validierung der Ergebnisse durchzuführen. Zusätzlich sollte auch der Effekt der räumlichen Auflösung der Eingangsparameter auf die resultierende Gefahrenhinweiskarte und die Eignung der Eingangsdaten für die angewandte Methode untersucht werden. Als Eingangsparameter lagen neben der räumlichen Verortung der gravitativen Massenbewegungen auch ein Datensatz zur Bodenkarte, die digitale Katastralmappe mit Daten zur Landnutzung, die geologische Karte und ein digitales Geländemodell mit 10m Rasterweite vor. Zusätzlich wurden Datensätze zu Hangneigung, Exposition, Distanz zum Flussnetz berechnet und Distanz zum Wegenetz berechnet.
Petschko H, Bell R, A. Brenning and Glade T (2012), "Landslide susceptibility modeling with generalized additive models - facing the heterogeneity of large regions", In Landslides and Engineered Slopes, Protecting Society through Improved Understanding. Banff, Alberta, Canada , pp. 769–777. Taylor & Francis.
Petschko H, Bell R, Leopold P, Heiss G and Glade T (2013), "Landslide Science and Practice, vol. 1: Landslide Inventory and Susceptibility and Hazard Zoning" , pp. 1-6. Springer.
Petschko H, Brenning A, Bell R, Goetz J and Glade T (2013), "Assessing the quality of landslide susceptibility maps - case study Lower Austria", Natural Hazards and Earth System Sciences Discussions. Vol. 1(2), pp. 1001-1050.
Abstract: Landslide susceptibility maps are helpful tools to identify areas which might be prone to future landslide occurrence. As more and more national and provincial authorities demand for these maps to be computed and implemented in spatial planning strategies, the quality of the landslide susceptibility map and of the model applied to compute them is of high interest. In this study we focus on the analysis of the model performance by a repeated k-fold cross-validation with spatial and random subsampling. Furthermore, the focus is on the analysis of the implications of uncertainties expressed by confidence intervals of model predictions. The cross-validation performance assessments reflects the variability of performance estimates compared to single hold-out validation approaches that produce only a single estimate. The analysis of the confidence intervals shows that in 85% of the study area, the 95% confidence limits fall within the same susceptibility class. However, there are cases where confidence intervals overlap with all classes from the lowest to the highest class of susceptibility to landsliding. Locations whose confidence intervals intersect with more than one susceptibility class are of high interest because this uncertainty may affect spatial planning processes that are based on the susceptibility level.
Petschko H, Glade T, Bell R, Schweigl J and Pomaroli G (2010), "Landslide inventories for regional early warning systems", In Proceedings of the International Conference 'Mountain Risks: Bringing Science to Society'. Strasbourg, November 24, 2010. CERG Editions.
Phillips J (1995), "Nonlinear Dynamics and the Evolution of Relief", Geomorphology., October, 1995. Vol. 14(1), pp. 57-64.
Abstract: Theories of landscape evolution, and available field evidence, suggest that topographic relief may increase, decrease, or remain relatively constant over time. The trend depends on the relative balance between endogenic and exogenic forces and/or the spatial scale. A straightforward mathematical argument shows that when relief generally decreases over time, or remains constant, landscape evolution is stable and non-chaotic. Chaotic, unstable topographic evolution produces divergence, where initial elevation differences (and subsequent perturbations) generally increase over time. This leads to, or at least towards, a conceptual model of landscape evolution. This model, based on nonlinear dynamical systems (NDS) theory, recognizes 10 modes - five stable and five chaotic - of topographic evolution. Together, these modes can accommodate existing theories and models of landscape evolution. No mode can persist indefinitely over geologic time, implying that landscapes inevitably undergo phases of increasing and decreasing relief (these phases may be quite long). Because the model can accommodate any observed trend in relief evolution, it is not falsifiable and is, therefore, not proposed as a theory. The NDS model does have implications with respect to the preservation of planar surfaces; the next step is to develop a testable hypothesis.
Phillips JD (2012), "Synchronization and scale in geomorphic systems", Geomorphology., January, 2012. Vol. 137(1), pp. 150-158.
Abstract: Geomorphic systems consist of coupled subsystems with traits of small-world networks (SWN), characterized by tightly connected clusters of components, with fewer connections between the clusters. Geomorphic systems based on scale hierarchies often exhibit a connected caveman small-world network (CCSWN) structure. SWNs are efficient for linking a large number of components with a relatively small number of links: but effects of CCSWN structure on synchronization and scale linkage have not been examined. Synchronization is analyzed via graph theory and applied to: (1) relationships among three levels of form-process interaction in stream channels; (2) hierarchical relationships of weathering systems at scales from weathering profiles to landscapes; and (3) interactions in fluviokarst systems at the scale of flow processes and of landscape evolution. Relationships among system components are represented as simple unweighted graphs. The largest eigenvalue of the adjacency matrix (spectral radius) reflects the critical coupling strength required to synchronize the system. The second-smallest eigenvalue of the Laplacian of the adjacency matrix (algebraic connectivity) is a measure of the synchronizability. In all examples both are much less than the maximum for networks of the same number of nodes. The sparseness of the networks is the major contributor to the low synchronization, but the specific pattern of connections ("wiring") is also significant. Where CCSWN structures arise naturally, they help explain how geomorphic effects are transmitted between disparate scales in the absence of obvious scale linkage. Where CCSWNs are an option for representation of geomorphic systems in models and data structures, they will not improve scale linkage, despite the efficiency of SWNs in other respects. Methods developed here can be applied to evaluating alternative spatial data structures or mapping strategies which either increase synchronization, supporting a lumping or aggregation approach, or decrease synchronization, indicating disaggregation or splitting into scale hierarchies. (C) 2011 Elsevier B.V. All rights reserved.
Phillips JD (2006), "Deterministic chaos and historical geomorphology: A review and look forward", Geomorphology., June, 2006. Vol. 76(1-2), pp. 109-121.
Abstract: The study of nonlinear dynamics in geomorphology has been dominated by analytical techniques derived largely from other fields. Ultimately, however, confronting nonlinear complexity requires problematizing from within a geomorphological context. This paper focuses on deterministic chaos. The major classes of techniques for detecting chaos in geomorphic systems are reviewed. While the long time series most amenable to traditional methods of chaos detection are only occasionally available to geomorphologists, there are methods for detecting chaos in spatial data, including qualitative and categorical data. Many of these are similar to, or are adaptations of, familiar techniques for partitioning within- and between-unit variation, and for identifying elementary uniform landscape units. The manifestations of chaos in landforms and landscapes take the form of divergent vs. convergent evolution (increasing vs. decreasing irregularity), disproportionality vs. proportionality of response to perturbations or initial variations, and the (lack of) geographical consistency or commonality of response. These also serve as criteria for distinguishing between achievement of a new steady-state and unstable divergence in interpreting geomorphic changes. Study of nonlinear dynamics in earth science need not be dominated by theoreticians and modellers, as complex nonlinear behaviors can be identified and diagnosed using the types of data, observations, and methods typically available to geomorphologists. Even more important is the need to further inform the study of nonlinear dynamics on the basis of field-based geomorphology. (c) 2005 Elsevier B.V. All rights reserved.
Phillips JD (2003), "Sources of nonlinearity and complexity in geomorphic systems", Progress In Physical Geography., March, 2003. Vol. 27(1), pp. 1-23.
Abstract: Nonlinearity is common in geomorphology, though not present or relevant in every geomorphic problem. It is often ignored, sometimes to the detriment of understanding surface processes and landforms. Nonlinearity opens up possibilities for complex behavior that are not possible in linear systems, though not all nonlinear systems are complex. Complex nonlinear dynamics have been documented in a number of geomorphic systems, thus nonlinear complexity is a characteristic of real-world landscapes, not just models. In at least some cases complex nonlinear dynamics can be directly linked to specific geomorphic processes and controls. Nonlinear complexities pose obstacles for some aspects of prediction in geomorphology, but provide opportunities and tools to enhance predictability in other respects. Methods and theories based on or grounded in complex nonlinear dynamics are useful to geomorphologists. These nonlinear frameworks can explain some phenomena not otherwise explained, provide better or more appropriate analytical tools, improve the interpretation of historical evidence and usefully inform modeling, experimental design, landscape management and environmental policy. It is also clear that no nonlinear formalism (and, as of yet, no other formalism) provides a universal meta-explanation for geomorphology. The sources of nonlinearity in geomorphic systems largely represent well-known geomorphic processes, controls and relationships that can be readily observed. A typology is presented, including thresholds, storage effects, saturation and depletion, self-reinforcing feedback, self-limiting processes, competitive feedbacks, multiple modes of adjustment, self-organization and hysteresis.
Piacentini D, Troiani F, Soldati M, Notarnicola C, Savelli D, Schneiderbauer S and Strada C (2012), "Statistical analysis for assessing shallow-landslide susceptibility in South Tyrol (south-eastern Alps, Italy)", Geomorphology., May, 2012. Vol. 151, pp. 196-206.
Abstract: This paper conducts a statistical analysis to determine shallow-landslide susceptibility in an approximately 7500-km(2) region of the south-eastern Alps (South Tyrol, Italy). The study applies the weight of evidence (WofE) method, which is useful in determining landslide susceptibility in large areas with complex geological and geomorphological settings. The statistical analysis and landslide susceptibility mapping are based on 882 past landslides, three geometric/topographic factors and two anthropogenic factors, which are the most relevant landslide predisposing factors. The quality of the proposed model, particularly the fitting performance, was assessed; the landslide database was divided into a training set to obtain the model and a validation set to estimate the model quality. The results show that the developed susceptibility model predicts an acceptable percentage (75%) of landslides. Therefore, the model can be useful and reliable for land planners and decision makers also due to its cost-effectiveness ratio. (C) 2012 Elsevier B.V. All rights reserved.
Pike R, Evans I and Hengl T (2009), "Geomorphometry: A brief guide", Developments in Soil Science. Vol. 33, pp. 3-30. Elsevier.
Abstract: Geomorphometry is the science of quantitative land-surface analysis. It evolved directly from geomorphology and quantitative terrain analysis, two disciplines that originated in 19th century geometry, physical geography, and the measurement of mountains. Modern geomorphometry addresses the refinement and processing of elevation data, description and visualization of topography, and a wide variety of numerical analyses. It focuses on the continuous land-surface, although it also includes the analysis of landforms, discrete features, such as watersheds. The operational goal of geomorphometry is extraction of measures and spatial features from digital topography. Geomorphometry supports countless applications in the Earth sciences, civil engineering, military operations, and entertainment. Geomorphometric analysis commonly entails five steps: Sampling a surface, generating and correcting a surface model, calculating land-surface parameters or objects, and applying the results. The three classes of parameters and objects include both landforms and pointmeasures, such as slope and curvature. Landform elements are fundamental spatial units having uniform properties. Complex analyses may combine several parameter maps and incorporate non-topographic data. The procedure that extracts most land-surface parameters and objects from a digital elevation model (DEM) is the neighborhood operation. Because parameters can be generated by different algorithms or sampling strategies, and vary with spatial scale, no DEM-derived map is definitive.
Pirulli M, Scavia C and Hungr O (2004), "Determination of rock avalanche run-out parameters through back analyses", In Landslides: Evaluation and Stabilization, Proceedings of the 9th International Symposium on Landslides. Rio de Janeiro, June 28 to July 2, 2004. Vol. 2, pp. 1361-1366. Taylor & Francis.
Abstract: The application of an analytical approach to the study of rock avalanche evolution requires that a value is assigned to each constitutive parameter of the assumed rheology before running an analysis. To define a range of typical values to be assigned to these parameters, a numerical model has been applied to several case histories of rock avalanches grouped in categories containing cases having similar characteristics. The obtained results should be useful in the prediction of run out of a potential landslide.
Poisel R, Angerer H, Pöllinger M, Kalcher T and Kittl H (2009), "Mechanics and velocity of the Lärchberg-Galgenwald landslide (Austria)", Engineering Geology. Vol. 109(1-2), pp. 57-66.
Abstract: The Lärchberg-Galgenwald landslide in Austria is situated in the south western slope of the Rantenbach valley, 2 km upstream of the town of Murau. The slope is made up of marbles some 300 m thick lying on a phyllite base some 140 m thick. The cracks of the main scarp, which are some 10 m wide, are monitored by wire extensometers and are opening with a precipitation dependent velocity of 30 cm per year. Numerical analyses showed that an overall volume of up to 10.000.000 m3 might bury the road in the valley and dam up the Rantenbach River, causing a debris flow. Investigations of the risks of the scenarios and of the costs of mitigation measures have shown that sealing of the surfaces of the roadways, drainage and diversion of precipitation and the realization of a watershed management project are highly economical. The excavation of a by-pass tunnel for the Rantenbach river in the opposite slope, as well as a toe weight at the bottom of the slope in connection with a covered tunnel for the Rantenbach River, appear not to be economical from the present point of view.
Pospichal B, Formayer H, Haas P and Nadeem I (2010), "Bias correction and localization of regional climate scenarios over mountainous area on a 1x1 km grid", In 10th EMS Annual Meeting, 10th European Conference on Applications of Meteorology (ECAM) Abstracts, held Sept. 13-17, 2010 in Zürich, Switzerland. http://meetings. copernicus. org/ems2010/, id. EMS2010-792. Vol. 1, pp. 792.
Abstract: The project "CC-WaterS" (Climate Change and Impacts on Water Supply) deals with challenges of water supply under the influence of existing and future climate change in Central and Eastern Europe. The meteorological part within this project assesses future climate conditions by using different regional climate models. The following three scenarios from the ENSEMBLES database are used: ECHAM5-REGCM3, ARPEGE-ALADIN, and HADCM3-PROMES with a spatial resolution 25 km each. For the whole target area, regionalization and bias correction by quantile mapping for temperature and precipitation is performed on a daily basis by using observations from the E-OBS dataset (25 km resolution) from the ENSEMBLES database. Over the Alpine region, a precipitation dataset from the ETH Zürich with a spatial resolution of about 18 km is applied. For one case study region in the Eastern Alps (containing the mountain areas of Hochschwab, Rax and Schneeberg in Styria/Lower Austria) a second step is taken to depict the small-scale variability in mountainous terrain. This is performed by using the precipitation analysis from the nowcasting system INCA provided by the Austrian Meteorological Service (ZAMG). These analyses combine ground-based and radar observations on a 1x1 km grid. With additional local temperature and precipitation observations, a localized, bias corrected precipitation scenario dataset on a daily base is produced. This presentation will discuss the method of bias correction and localization and the results for the 21st century. In a second step, uncertainties will be quantified, both resulting from the climate scenarios as well as from the localization method applied.
Pötsch E, Krautzer B and Hopkins A (2011), "Grassland Farming and Land Management Systems in Mountainous Regions", In Proceedings of the 16th Symposium of the European Grassland Federation. Gumpenstein, Austria, 29.-30. August 2011, 2011.
Pourghasemi HR, Jirandeh AG, Pradhan B, Xu C and Gokceoglu C (2013), "Landslide susceptibility mapping using support vector machine and GIS at the Golestan Province, Iran", Journal of Earth System Science., April, 2013. Vol. 122(2), pp. 349-369.
Abstract: The main goal of this study is to produce landslide susceptibility map using GIS-based support vector machine (SVM) at Kalaleh Township area of the Golestan province, Iran. In this paper, six different types of kernel classifiers such as linear, polynomial degree of 2, polynomial degree of 3, polynomial degree of 4, radial basis function (RBF) and sigmoid were used for landslide susceptibility mapping. At the first stage of the study, landslide locations were identified by aerial photographs and field surveys, and a total of 82 landslide locations were extracted from various sources. Of this, 75% of the landslides (61 landslide locations) are used as training dataset and the rest was used as (21 landslide locations) the validation dataset. Fourteen input data layers were employed as landslide conditioning factors in the landslide susceptibility modelling. These factors are slope degree, slope aspect, altitude, plan curvature, profile curvature, tangential curvature, surface area ratio (SAR), lithology, land use, distance from faults, distance from rivers, distance from roads, topographic wetness index (TWI) and stream power index (SPI). Using these conditioning factors, landslide susceptibility indices were calculated using support vector machine by employing six types of kernel function classifiers. Subsequently, the results were plotted in ArcGIS and six landslide susceptibility maps were produced. Then, using the success rate and the prediction rate methods, the validation process was performed by comparing the existing landslide data with the six landslide susceptibility maps. The validation results showed that success rates for six types of kernel models varied from 79% to 87%. Similarly, results of prediction rates showed that RBF (85%) and polynomial degree of 3 (83%) models performed slightly better than other types of kernel (polynomial degree of 2 = 78%, sigmoid = 78%, polynomial degree of 4 = 78%, and linear = 77%) models. Based on our results, the differences in the rates (success and prediction) of the six models are not really significant. So, the produced susceptibility maps will be useful for general land-use planning.
Pourghasemi HR, Pradhan B and Gokceoglu C (2012), "Application of fuzzy logic and analytical hierarchy process (AHP) to landslide susceptibility mapping at Haraz watershed, Iran", Natural Hazards., September, 2012. Vol. 63(2), pp. 965-996.
Abstract: The main goal of this study is to produce landslide susceptibility maps of a landslide-prone area (Haraz) in Iran by using both fuzzy logic and analytical hierarchy process (AHP) models. At first, landslide locations were identified by aerial photographs and field surveys, and a total of 78 landslides were mapped from various sources. Then, the landslide inventory was randomly split into a training dataset 70 % (55 landslides) for training the models and the remaining 30 % (23 landslides) was used for validation purpose. Twelve data layers, as the landslide conditioning factors, are exploited to detect the most susceptible areas. These factors are slope degree, aspect, plan curvature, altitude, lithology, land use, distance from rivers, distance from roads, distance from faults, stream power index, slope length, and topographic wetness index. Subsequently, landslide susceptibility maps were produced using fuzzy logic and AHP models. For verification, receiver operating characteristics curve and area under the curve approaches were used. The verification results showed that the fuzzy logic model (89.7 %) performed better than AHP (81.1 %) model for the study area. The produced susceptibility maps can be used for general land use planning and hazard mitigation purpose.
Pradhan B and Lee S (2010), "Regional landslide susceptibility analysis using back-propagation neural network model at Cameron Highland, Malaysia", Landslides., March, 2010. Vol. 7(1), pp. 13-30.
Abstract: This paper presents landslide susceptibility analysis around the Cameron Highlands area, Malaysia using a geographic information system (GIS) and remote sensing techniques. Landslide locations were identified in the study area from interpretation of aerial photographs and field surveys. Topographical, geological data and satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. Ten landslide occurrence factors were selected as: topographic slope, topographic aspect, topographic curvature and distance from drainage, lithology and distance from lineament, soil type, rainfall, land cover from SPOT 5 satellite images, and the vegetation index value from SPOT 5 satellite image. These factors were analyzed using an advanced artificial neural network model to generate the landslide susceptibility map. Each factor's weight was determined by the back-propagation training method. Then, the landslide susceptibility indices were calculated using the trained back-propagation weights, and finally, the landslide susceptibility map was generated using GIS tools. The results of the neural network model suggest that the effect of topographic slope has the highest weight value (0.205) which has more than two times among the other factors, followed by the distance from drainage (0.141) and then lithology (0.117). Landslide locations were used to validate the results of the landslide susceptibility map, and the verification results showed 83% accuracy. The validation results showed sufficient agreement between the computed susceptibility map and the existing data on landslide areas.
Prager C, Zangerl C, Patzelt G and Brandner R (2008), "Age distribution of fossil landslides in the Tyrol (Austria) and its surrounding areas", Natural Hazards and Earth System Sciences. Vol. 8(2), pp. 377-407.
Abstract: Some of the largest mass movements in the Alps cluster spatially in the Tyrol (Austria). Fault-related valley deepening and coalescence of brittle discontinuities structurally controlled the progressive failure and the kinematics of several slopes. To evaluate the spatial and temporal landslide distribution, a first comprehensive compilation of dated mass movements in the Eastern Alps has been made. At present, more than 480 different landslides in the Tyrol and its surrounding areas, including some 120 fossil events, are recorded in a GIS-linked geodatabase. These compiled data show a rather continuous temporal distribution of landslide activities, with (i) some peaks of activity in the early Holocene at about 10 500-9400 cal BP and (ii) in the Tyrol a significant increase of deep-seated rockslides in the Subboreal at about 4200-3000 cal BP. The majority of Holocene mass movements were not directly triggered by deglaciation processes, but clearly took a preparation of some 1000 years, after ice withdrawal, until slopes collapsed. In view of this, several processes that may promote rock strength degradation are discussed. After the Late-Glacial, slope stabilities were affected by stress redistribution and by subcritical crack growth. Fracture propagating processes may have been favoured by glacial loading and unloading, by earthquakes and by pore pressure fluctuations. Repeated dynamic loading, even if at subcritical energy levels, initiates brittle fracture propagation and thus substantially promotes slope instabilities. Compiled age dating shows that several landslides in the Tyrol coincide temporally with the progradation of some larger debris flows in the nearby main valleys and, partially, with glacier advances in the Austrian Central Alps, indicating climatic phases of increased water supply. This gives evidence of elevated pore pressures within the intensely fractured rock masses. As a result, deep-seated gravitational slope deformations are induced by complex and polyphase interactions of lithological and structural parameters, morphological changes, subcritical fracture propagation, variable seismic activity and climatically controlled groundwater flows.
Prokop A and Panholzer H (2009), "Assessing the capability of terrestrial laser scanning for monitoring slow moving landslides", Natural Hazards and Earth System Sciences. Vol. 9(6), pp. 1921-1928.
Abstract: Digital elevation models (DEM) are widely used to determine characteristics of mass movement processes such as accumulation and deposition of material, volume estimates or the orientation of discontinuities. To create such DEMs point cloud data is provided by terrestrial laser scanning (TLS) and recently used for analysis of mass movements. Therefore the reliability of TLS data was investigated in a comparative study with tachymetry. The main focus was on the possibility of determining movement patterns of landslides < 100 mm. Therefore, several post processing steps are needed and the reliability of those were analyzed. The post processing steps that were investigated include: (1) The registration process is a crucial step considering long term TLS monitoring of an object and can be significantly improved using an iterative closest point (ICP) algorithm; (2) Filtering methods are necessary to create DEMs in order to separate favored laser points on the terrain surface (ground points) from topographically irrelevant points (non-ground-points). Therefore GIS tools were applied. Surfaces with and without vegetation cover were differentiated; (3) Displacement vectors are used to determine slope movement rates. They were created from TLS data after the computation of true orthophotos. Using the methodology presented it was not possible to determine movement rates < 50 mm per period. However, if the quality of the point density is described and areas with very low point density are detected, reliable conclusions can be made regarding slope movement patterns and erosion and deposition of material for changes < 100 mm for the investigated slope.
Quan Luna B (2012), "Dynamic numerical run out modeling for quantitative landslide risk assessment". Thesis at: University of Twente.
Abstract: Landslides and debris flows are geomorphologic events that may pose danger to different components of mountainous societies. This danger is not only the result of the process as such, but of the interaction with human systems and their associated vulnerabilities. Understanding, forecasting and controlling the hazard associated to this type of slope movements is still an empirical task which requires a mix of qualitative and quantitative analyses. The development of numerical dynamic run-out models has made a dramatic change in the study of hazardous processes, as these allow the simulation of possible future scenarios, including ones that have no historical evidences. Dynamic computer models have the potential to simulate geomorphologic processes with an acceptable degree of accuracy. Once this is achieved, a range of potential hazard scenarios can be analyzed and the results can be used to inform local authorities and the population in order to respond to these hazards and plan to reduce the associated risks. For this reason, it is important to evaluate the reliability and consistency of these dynamic models that integrate the physical descriptions of the landslide process in a numerical scheme, embedded in a Geographical Information System (GIS).
Raetzo H and Lateltin O (2003), "Extremereignisse und Klimaänderung" Bern Organe consultatif sur les changements climatiques (OcCC).
Abstract: Ein grosses Wasserangebot über längere Zeit kann Massenbewegungen auslösen. Ungefähr 7% der Gesamtfläche der Schweiz weisen instabile Hänge auf. Die Zunahme der Niederschläge in der Westschweiz seit den 1970er Jahren hat in verschiedenen Rutschgebieten zu einer Zunahme der Bewegungen geführt. In jüngster Vergangenheit haben zunehmende Winterniederschläge in Kombination mit grossen Schmelzwassermengen ebenfalls mehr Rutschungen ausgelöst. Hanginstabilitäten könnten wegen des Gletscherrückzugs, der auftauenden Permafrostböden, zunehmender Winterniederschläge und der steigenden Schneefallgrenze allgemein zunehmen.
Raetzo H, Wegmüller U, Strozzi T, Marks F and Farina P (2007), "Monitoring of lumnez landslide with ERS and ENVISAT SAR data", In Proceeding Envisat Symposium 2007. Montreux, Switzerland.
Abstract: As part of the ESA Terrafirma Project an interferometric point target analysis (IPTA) was conducted to monitor the LUMNEZ landslide. The main interferometric result consists of the average line-of-sight deformation rates and the deformation histories for the selected points. The observed deformation rates reach values up to several centimeters per year. The interferometric result was delivered to the Swiss Federal Office for Environment and to the University of Florence where it was further interpreted. Combining IPTA results with the use of digital terrain data, aerial imagery and in-situ data a geomorphologic and geological interpretation of the Lumnez landslide was carried out. DTM data and aerial imagery allowed a geomorphologic zonation of the unstable slope taking into account derivates of the DTM as shaded relief, slope and aspect map. A field survey enabled the assessment of findings from the satellite monitoring, with the identification of damaged buildings and morphologic evidences connected to the slope movements.
Raetzo-Brülhart (1997), "Massenbewegungen im Gurnigelflysch und Einfluss der Klimaänderung" vdf Hochschulverlag AG.
Raschendorfer I (1958), "Blaikentypen in den Ostalpen. Kennzeichnung von Rutschflächen nach den Vegetationsstufen zum Zwecke der Grünverbauung", Schlern-Schriften. Vol. 188, pp. 91-112.
Raska P, Klimes J and Dubisar J (2013), "Using local archive sources to reconstruct historical landslide occurrence in selected urban regions of the czech republic examples from regions with different historical development", Land Degrad. Develop..
Abstract: Historical documentary sources from two regions with contrasting historical and social development were examined for information about landslide occurrence and characteristics. The archive search was complemented with limited field work to acquire information about the degree of recent landslide activity and land use. The results from two study areas (Ušti­ nad Labem in North Bohemia and Zlin in East Moravia) show considerable differences in the types of historical documentary source, their availability and the information they record. It is concluded that local newspapers that include special sections focusing on regional events are the best data sources for the landslide study. The reliability of the acquired historical landslide occurrence frequencies is generally not very good, but it does show notable regional differences caused by not only the availability of documentary sources but also the dynamics of the natural processes responsible for the landslide events. A reconstruction of the landslide activity during the last 70 or more years was carried out for selected sites. The reconstruction showed that the occurrence of historical landslides is only rarely respected in recent land use within both studied urban areas. Historical landslide information could be well used for site-specific landslide hazard assessment. Nevertheless, the use of this information to construct a historical landslide database on the regional or country level is limited only to certain regions of the Czech Republic. Copyright © 2012 John Wiley & Sons, Ltd.
Rau J-Y, Chang K-T, Shao Y-C and Lau C-C (2012), "Semi-automatic shallow landslide detection by the integration of airborne imagery and laser scanning data", Natural Hazards., March, 2012. Vol. 61(2), pp. 469-480.
Abstract: Landslide mapping is essential for effective watershed management. In Taiwan, a typhoon or earthquake event can trigger hundreds, even thousands, of shallow landslides in mountainous watersheds. Thus, improving the efficiency of landslide mapping by means of remote sensing techniques is an important issue. This study proposes a new method that uses concurrent aerial laser scanning (ALS) data and color ortho-imagery as input data: the topographic indices of slope, surface roughness, and object height model can be derived from the ALS data and the Green-Red Vegetation Index from the ortho-images. The method first uses these topographic and spectral indices in a global, semi-automatic algorithm to separate landslide from non-landslide pixels. It then offers a region growing tool and a 3D Eraser/Painter to edit detected landslides locally. These global and local operations are designed with a user interface, which is intuitive and user-friendly. Results from four test sites in a mountainous watershed prove that the method is easy, accurate, and suitable for landslide mapping in Taiwan.
Razak KA, Santangelo M, Van Westen CJ, Straatsma MW and de Jong SM (2013), "Generating an optimal DTM from airborne laser scanning data for landslide mapping in a tropical forest environment", Geomorphology., May, 2013. Vol. 190, pp. 112-125.
Abstract: Landslide inventory maps are fundamental for assessing landslide susceptibility, hazard, and risk. In tropical mountainous environments, mapping landslides is difficult as rapid and dense vegetation growth obscures landslides soon after their occurrence. Airborne laser scanning (ALS) data have been used to construct the digital terrain model (DTM) under dense vegetation, but its reliability for landslide recognition in the tropics remains surprisingly unknown. This study evaluates the suitability of ALS for generating an optimal DTM for mapping landslides in the Cameron Highlands, Malaysia. For the bare-earth extraction, we used hierarchical robust filtering algorithm and a parameterization with three sequential filtering steps. After each filtering step, four interpolations techniques were applied, namely: (i) the linear prediction derived from the SCOP++ (SCP), (ii) the inverse distance weighting (IDW), (iii) the natural neighbor (NEN) and (iv) the topo-to-raster (T2R). We assessed the quality of 12 DTMs in two ways: (1) with respect to 448 field-measured terrain heights and (2) based on the interpretability of landslides. The lowest root-mean-square error (RMSE) was 0.89 m across the landscape using three filtering steps and linear prediction as interpolation method. However, we found that a less stringent DTM filtering unveiled more diagnostic micro-morphological features, but also retained some of vegetation. Hence, a combination of filtering steps is required for optimal landslide interpretation, especially in forested mountainous areas. IDW was favored as the interpolation technique because it combined computational times more reasonably without adding artifacts to the DTM than T2R and NEN, which performed relatively well in the first and second filtering steps, respectively. The laser point density and the resulting ground point density after filtering are key parameters for producing a DTM applicable to landslide identification. The results showed that the ALS-derived DTMs allowed mapping and classifying landslides beneath equatorial mountainous forests, leading to a better understanding of hazardous geomorphic problems in tropical regions. (C) 2013 Elsevier B.V. All rights reserved.
Razak KA, Straatsma MV, Van Westen CJ and Malet JP (2009), "Utilization of airborne LiDAR data for landslide mapping in forested terrain: status and challenges", In Proceedings of the 10th South East Asian Survey Congress (SEASC). Bali, Indonesia, August, 2009.
Abstract: With the advancement in sensor technology and point clouds processing algorithms, the capability of Airborne LIDAR data for landslide mapping in forested terrain is much promising. Most of the available air-based platform products either from an aerial-photograph, satellite imagery or synthetic aperture radar are not appropriate for interpretation of landslide features which are covered by dense vegetation. Mapping the landslides in such environment requires additional information that can help the interpreters to recognise landslide characteristics and later on be used to distinguish landslide activities. In this research, we present the status and challenges of utilizing the high-resolution airborne LIDAR data for landslide mapping in forested terrain. European dataset in Barcelonnette, Southern French Alps has been used. Amongst the important issues in this research is bare earth extraction. In order to preserve the important geomorphological feature, bare earth extraction based on hierarchical robust filtering is presented with a suitable filter parameterization. Finally, high-resolution Digital Terrain Model (DTM) is used to calculate the local topography roughness and characterize the landslide morphology.
Razak KA, Straatsma MW, van Westen CJ, Malet JP and de Jong SM (2011), "Airborne laser scanning of forested landslides characterization: Terrain model quality and visualization", Geomorphology., March, 2011. Vol. 126(1-2), pp. 186-200.
Abstract: Mapping complex landslides under forested terrain requires an appropriate quality of digital terrain models (DTMs), which preserve small diagnostic features for landslide classification such as primary and secondary scarps, cracks, and displacement structures (flow-type and rigid-type). Optical satellite imagery, aerial photographs and synthetic aperture radar images are less effective to create reliable DTMs under tree coverage. Here, we utilized a very high density airborne laser scanning (ALS) data, with a point density of 140 points m(-2) for generating a high quality DTM for mapping landslides in forested terrain in the Barcelonnette region, the Southern French Alps. We quantitatively evaluated the preservation of morphological features and qualitatively assessed the visualization of ALS-derived DTMs. We presented a filter parameterization method suitable for landslide mapping and compared it with two default filters from the hierarchical robust interpolation (HRI) and one default filter from the progressive TIN densification (PTD) method. The results indicate that the vertical accuracy of the DTM derived from the landslide filter is about 0.04 m less accurate than that from the PTD filter. However, the landslide filter yields a better quality of the image for the recognition of small diagnostic features as depicted by expert image interpreters. Several DTM visualization techniques were compared for visual interpretation. The openness map visualized in a stereoscopic model reveals more morphologically relevant features for landslide mapping than the other filter products. We also analyzed the minimal point density in ALS data for landslide mapping and found that a point density of more than 6 points m(-2) is considered suitable for a detailed analysis of morphological features. This study illustrates the suitability of high density ALS data with an appropriate parameterization for the bare-earth extraction used for landslide identification and characterization in forested terrain. (C) 2010 Elsevier B.V. All rights reserved.
Reid LM and Page MJ (2003), "Magnitude and frequency of landsliding in a large New Zealand catchment", Geomorphology., January, 2003. Vol. 49(1-2), pp. PII S0169-555X(02)00164-2.
Abstract: Knowledge of long-term average rates of erosion is necessary if factors affecting sediment yields from catchments are to be understood. Without such information, it is not possible to assess the potential influence of extreme storms, and, therefore, to evaluate the relative importance of various components of a sediment budget. A study of the sediment budget for the Waipaoa catchment, North Island, New Zealand, included evaluation of long-term rates of landsliding for six landslide-prone land systems in the catchment. The number of landslides per unit area generated by each of several storms was counted on sequential aerial photographs and correlated with the magnitude of the corresponding storm. The resulting relationships were combined with magnitude-frequency relationships derived for storms from 70- to 100-year rainfall records in the area to estimate a longterm magnitude-frequency relationship for landsliding for each land system. The long-term average values of the areal landslide frequency (number of slides per unit area per unit time) were then calculated from these relationships. The volumes of a sample of landslide scars were measured in the field, and the proportion of slides that deliver sediment to channels was determined from aerial photographs. These measurements then allowed calculation of the long-term average rate of sediment production to streams from landslides for different land systems and types of vegetation. Results suggest that shallow landslides currently contribute about 15+/-5% of the suspended sediment load in the Waipaoa River above the Kanakanaia gauging station, and that 75% of the sediment production from the landslides occurs during storms with recurrence intervals of less than 27 years. Reforestation of 6.3% (93 km(2)) of the slide-prone lands in the catchment between 1990 and 1995 resulted in a calculated decrease in slide-derived sediment of 10%. Calculations suggest that reforestation of an additional 3% (66 kM(2)) Of the catchment in areas with the most sensitive combinations of land system and storm regime could decrease the total sediment inputs from landsliding by about 20%. (C) 2002 Elsevier Science B.V. All rights reserved.
Reid ME, Baum RL, LaHusen RG and Ellis WL (2008), "Capturing landslide dynamics and hydrologic triggers using near-real-time monitoring", Landslides and Engineered Slopes: From the Past To the Future, Vols 1 and 2., In Landslides and engineered slopes from the past to the future. Proceedings of the Tenth International Symposium on Landslides and Engineered Slopes. Xian, China, 30 June-4 July 2008, 2008. Vol. 1, pp. 179–191. Taylor and Francis, London.
Abstract: Near-real-time monitoring of active landslides or landslide-prone hillslopes can provide immediate notification of landslide activity, as well as high-quality data sets for understanding the initiation and movement of landslides. Typical components of ground-based, near-real-time landslide monitoring systems include field sensors, data acquisition systems, remote telemetry, and software for base-station data processing and dissemination. For the last several decades, we have used these monitoring tools to investigate different landslide processes. Some of our field applications have determined the groundwater conditions controlling slow-moving landslides, detected 3-D displacements of large rock masses, and characterized the transient near-surface hydrology triggering shallow landsliding.
Remaitre A, Malet JP, Maquaire O, Ancey C and Locat J (2005), "Flow behaviour and runout modelling of a complex debris flow in a clay-shale basin", Earth Surface Processes and Landforms., April, 2005. Vol. 30(4), pp. 479-488.
Abstract: Identification of debris-flow hazard areas necessitates the knowledge of the flow thickness and the runout distance. Both have been investigated using a numerical runout model. On the Faucon stream (South French Alps), representative of clay-shale basins, results of various rheological tests and numerical experiments are presented and discussed. The calibration of the model was undertaken using the results of both geomorphological surveys and sedimentological analyses. Rheological tests using either a parallel-plate rheometer, a coaxial rheometer, slump tests, and an inclined plane were carried out on several samples. Results have shown that the flow behaviour could be described by an Herschel-Bulkley constitutive equation. The rheological responses of several natural suspensions collected from surficial deposits (sandstones, moraines, weathered black marls) were also investigated. In order to model the runout of the flow, the model BING was used. The model describes well the influence of each type of sediment on the behaviour (runout distance, deposit thickness) of the flow, although the velocities were significantly overestimated. Different risk scenarios are tested and discussed. Copyright (c) 2005 John Wiley & Sons, Ltd.
Renwick W, Brumbaugh R and Loeher L (1982), "Landslide Morphology and Processes On Santa Cruz Island, California", Geografiska Annaler Series A-physical Geography. Vol. 64(3-4), pp. 149-159.
Abstract: An episode of unusually intense rainfall triggered over a thousand landslides on Santa Cruz Island, California, during the winter of 1977-78. These included large, deep-seated failures, composite mudflows, and hundreds of shallow soil slips. In this study, landslide occurrence is examined in relation to lithologic, pedologic, topographic, and vegetational conditions. Their effects on soil permeability, water movement patterns, and shear strength are found to be related to landslide morphology and process.
Rickli C, Bucher H, Böll A and Raetzo H (2004), "Untersuchungen zu oberflächennahen Rutschungen des Jahres 2002 im Napfgebiet und in der Region Appenzell", Bull. angew. Geol. Vol. 9(1), pp. 37-49.
Abstract: Mehrere Unwetter führten in der Schweiz im Jahr 2002 zu zahlreichen oberflächennahen Rutschungen und grossen Schäden an Menschenleben und Sachwerten. Die Ereignisse boten jedoch auch Gelegenheit, die Kenntnisse bezüglich der Auslösung und dem Abfliessvorgang von oberflächennahen Rutschungen zu verbessern. Im Herbst 2002 wurde deshalb ein Forschungsprojekt in Angriff genommen mit dem Ziel, die während der Unwetter entstandenen Hangprozesse zu dokumentieren, zu analysieren und damit insbesondere die Grundlagen hinsichtlich der Beurteilung und Kartierung von oberflächennahen Rutschungen zu verbessern. In den zwei Schadengebieten «Napf» (16.7.02) und «Appenzell» (31.8.02) wurde je ein Untersuchungsperimeter definiert. Innerhalb dieser Perimeter wurden insgesamt 133 Rutschungen im Feld aufgesucht und analysiert. Dabei erfolgte eine Beurteilung sowohl geomorphologischer, geologischer und geotechnischer Parameter wie auch boden- und vegetationskundlicher Aspekte. Der vorliegende Artikel enthält einige Resultate der entsprechenden Untersuchung.
Rickli C and Graf F (2009), "Effects of forests on shallow landslides-case studies in Switzerland", For. Snow Landsc. Res. Vol. 82(1), pp. 33-44.
Abstract: Shallow landslides triggered off by heavy rainfall are recurrent phenomena on steep slopes. It is widely recognised that vegetation, particularly forest, can stabilize steep slopes. However, there is considerable argument about to what extent trees reduce hydro-geomorphic hazards. This article discusses the effects of forest on shallow landslides on the basis of detailed landslide inventories. A total of six study areas were investigated after different rainfall events in Switzerland. Within the boundary of these areas, all shallow landslides that occurred during the specific rainfall events were mapped and related to the site characteristics of the source area, such as its geomorphology and vegetation. Only minor differences in dimensions were found between landslides in forest areas and those in open land. On the other hand, the field studies showed that landslide densities were lower in forested terrain than in open land. Furthermore, landslides mapped in forests occurred on steeper slopes than slides mapped in open land. The application of these results for predicting landslide occurrence is discussed.
Rickli C, Zimmerli P and Böll A (2001), "Effects of vegetation on shallow landslides: an analysis of the events of August 1997 in Sachseln, Switzerland", In International conference on landslides - causes, impacts and countermeasures. Davos, Switzerland, 17-21 June, 2001. , pp. 575-585. Glückauf.
Abstract: An extreme thunderstorm with heavy rainfall triggered a large number of shallow landslides in the region of Sachseln, Switzerland. These events provided an opportunity to investigate the effects of different types of forest management and land use on landslide activity. A number of 280 shallow landslides were analysed in the field. The results show that beside hydrological, geological and geotechnical parameters, vegetation is a decisive factor.
Rickli C, Zürcher K, Frey W and Lüscher P (2002), "Wirkungen des Waldes auf oberflächennahe Rutschprozesse", Schweizerische Zeitschrift für Forstwesen. Vol. 153/11, pp. 437-445.
Abstract: Im Feld analysiert wurden 280 oberflächennahe Rutschungen, die 1997 durch ein äusserst starkes Unwetter bei Sachseln, Kanton Obwalden, ausgelöst worden waren. Die Resultate zeigen unter anderem, dass der Zustand und die Struktur des Waldes die Stabilität von abschüssigen Hängen wesentlich beeinflussen.
Robinson D, Campbell C, Hopmans J, Hornbuckle B, Jones SB, Knight R, Ogden F, Selker J and Wendroth O (2008), "Soil moisture measurement for ecological and hydrological watershed-scale observatories: A review", Vadose Zone Journal. Vol. 7(1), pp. 358-389. Soil Science Society.
Abstract: At the watershed scale, soil moisture is the major control for rainfall–runoff response, especially where saturation excess runoff processes dominate. From the ecological point of view, the pools of soil moisture are fundamental ecosystem resources providing the transpirable water for plants. In drylands particularly, soil moisture is one of the major controls on the structure, function, and diversity in ecosystems. In terms of the global hydrological cycle, the overall quantity of soil moisture is small, ca. 0.05%; however, its importance to the global energy balance and the distribution of precipitation far outweighs its physical amount. In soils it governs microbial activity that affects important biogeochemical processes such as nitrification and CO2 production via respiration. During the past 20 years, technology has advanced considerably, with the development of different electrical sensors for determining soil moisture at a point. However, modeling of watersheds requires areal averages. As a result, point measurements and modeling grid cell data requirements are generally incommensurate. We review advances in sensor technology, particularly emerging geophysical methods and distributed sensors, aimed at bridging this gap. We consider some of the data analysis methods for upscaling from a point to give an areal average. Finally, we conclude by offering a vision for future research, listing many of the current scientific and technical challenges.
Roch KH, Chwatal W and Bruckl E (2006), "Potentials of monitoring rock fall hazards by GPR: considering as example the results of Salzburg", Landslides., May, 2006. Vol. 3(2), pp. 87-94.
Abstract: A part of the IUGS-UNESCO research project "Landslide Hazard Assessment and Cultural Heritage" (IGCP-Project No. 425) includes testing the application of geophysical methods for assessing hazard risks to people and cultural assets. In this work, Austria contributed with a study on the assessment of rock-fall hazards. As the Old Town of Salzburg is a prime example of such hazards, systematic GPR-measurements were made on major rock surfaces. The aim of the exploration with GPR was to assess the potential of the method for monitoring rock walls. That is, whether structures in the rock mass which could become important when considering the risk of a rock fall, can be imaged. To manage this problem successfully, moving the antenna over the rough rock surface was made as regular as possible. The effects of vegetation lifting the antenna from the rock surface and of overhanging regions could not be avoided. Due to the loss of coupling of the antenna and the change of radiation pattern, some interference of the records occurred. Thus, only after processing could it become clear which reflections came from within the rock. A three-dimensional survey of discontinuities in the rock requires accurate mapping of the rock surface by photogrammetric methods, to get a digital terrain model for the analysis of the GPR records. The results of repeated measurements have proved to be of essential relevance. They have shown that it is possible to reveal changes with time. For the interpretation of such observations, modeling is a very useful tool.
Romani L, de Avila A, Chino D, Zullo J, Chbeir R, Traina A and Traina A (2013), "A New Time Series Mining Approach Applied to Multitemporal Remote Sensing Imagery", Geoscience and Remote Sensing, IEEE Transactions on. Vol. 51(1), pp. 140-150.
Abstract: In this paper, we present a novel unsupervised algorithm, called CLimate and rEmote sensing Association patteRns Miner, for mining association patterns on heterogeneous time series from climate and remote sensing data integrated in a remote sensing information system developed to improve the monitoring of sugar cane fields. The system, called RemoteAgri, consists of a large database of climate data and low-resolution remote sensing images, an image preprocessing module, a time series extraction module, and time series mining methods. The preprocessing module was projected to perform accurate geometric correction, what is a requirement particularly for land and agriculture applications of satellite images. The time series extraction is accomplished through a graphical interface that allows easy interaction and high flexibility to users. The time series mining method transforms series to symbolic representation in order to identify patterns in a multitemporal satellite images and associate them with patterns in other series within a temporal sliding window. The validation process was achieved with agroclimatic data and NOAA-AVHRR images of sugar cane fields. Results show a correlation between agroclimatic time series and vegetation index images. Rules generated by our new algorithm show the association patterns in different periods of time in each time series, pointing to a time delay between the occurrences of patterns in the series analyzed, corroborating what specialists usually forecast without having the burden of dealing with many data charts.
Rooney DJ and Lowery B (2000), "A profile cone penetrometer for mapping soil horizons", Soil Science Society of America Journal., November, 2000. Vol. 64(6), pp. 2136-2139. Soil Sci Soc Amer.
Abstract: Accurate soil mapping at a fine scale is needed for site-specific farming, research on solute transport, and many other applications requiring detailed analysis of both the depth and thickness of soil horizons. Soil mapping techniques currently used are too costly to address the spatial variability of soil mapping units. We propose the use of a profile cone penetrometer (PCP) to assist in mapping soil properties at a landscape scale. Data collected with the PCP show clear changes in soil properties with depth, and were confirmed using profile descriptions from soil pits as well as 4.3-cm-diam soil cores. Combining three-dimensional PCP data with soil attribute information will provide a rapid and effective means to digitally update soil surveys and improve the efficiency and cost effectiveness of sampling techniques.
Rosito Listo FdL and Vieira BC (2012), "Mapping of risk and susceptibility of shallow-landslide in the city of Sao Paulo, Brazil", Geomorphology., October, 2012. Vol. 169, pp. 30-44.
Abstract: In the city of Sao Paulo, where about 11 million people live, landslides and flooding occur frequently, especially during the summer. These landslides cause the destruction of houses and urban equipment, economic damage, and the loss of lives. The number of areas threatened by landslides has been increasing each year. The objective of this article is to analyze the probability of risk and susceptibility to shallow landslides in the Limoeiro River basin, which is located at the head of the Aricanduva River basin, one of the main hydrographic basins in the city of Sao Paulo. To map areas of risk, we created a cadastral survey form to evaluate landslide risk in the field. Risk was categorized into four levels based on natural and anthropogenic factors: R1 (low risk), R2 (average risk), R3 (high risk), and R4 (very high risk). To analyze susceptibility to shallow landslides, we used the SHALSTAB (Shallow Landsliding Stability) mathematical model and calculated the Distribution Frequency (DF) of the susceptibility classes for the entire basin. Finally, we performed a joint analysis of the average Risk Concentration (RC) and Risk Potential (RP). We mapped 14 risk sectors containing approximately 685 at-risk homes, more than half of which presented a high (R3) or very high (R4) probability of risk to the population. In the susceptibility map, 41% of the area was classified as stable and 20% as unconditionally unstable. Although the latter category accounted a smaller proportion of the total area, it contained a concentration (RC) of 41% of the mapped risk areas with a risk potential (RP) of 12%. We found that the locations of areas predicted to be unstable by the model coincided with the risk areas mapped in the field. This combination of methods can be applied to evaluate the risk of shallow landslides in densely populated areas and can assist public managers in defining areas that are unstable and inappropriate for occupation. (C) 2012 Elsevier B.V. All rights reserved.
Rossi G, Catani F, Leoni L, Segoni S and Tofani V (2013), "HIRESSS: a physically based slope stability simulator for HPC applications", Natural Hazards and Earth System Science. Vol. 13(1), pp. 151-166.
Abstract: HIRESSS (HIgh REsolution Slope Stability Simulator) is a physically based distributed slope stability simulator for analyzing shallow landslide triggering conditions in real time and on large areas using parallel computational techniques. The physical model proposed is composed of two parts: hydrological and geotechnical. The hydrological model receives the rainfall data as dynamical input and provides the pressure head as perturbation to the geotechnical stability model that computes the factor of safety (FS) in probabilistic terms. The hydrological model is based on an analytical solution of an approximated form of the Richards equation under the wet condition hypothesis and it is introduced as a modeled form of hydraulic diffusivity to improve the hydrological response. The geotechnical stability model is based on an infinite slope model that takes into account the unsaturated soil condition. During the slope stability analysis the proposed model takes into account the increase in strength and cohesion due to matric suction in unsaturated soil, where the pressure head is negative. Moreover, the soil mass variation on partially saturated soil caused by water infiltration is modeled.
The model is then inserted into a Monte Carlo simulation, to manage the typical uncertainty in the values of the input geotechnical and hydrological parameters, which is a common weak point of deterministic models. The Monte Carlo simulation manages a probability distribution of input parameters providing results in terms of slope failure probability. The developed software uses the computational power offered by multicore and multiprocessor hardware, from modern workstations to supercomputing facilities (HPC), to achieve the simulation in reasonable runtimes, compatible with civil protection real time monitoring.
Rosso R, Rulli MC and Vannucchi G (2006), "A physically based model for the hydrologic control on shallow landsliding", Water Resources Research., June, 2006. Vol. 42(6), pp. W06410. Amer Geophysical Union.
Abstract: Both rainfall intensity and duration take part in determining the hydrologic conditions favorable to the occurrence of shallow landslides. Hydrogeomorphic models of slope stability generally account for the dependence of landsliding on soil mechanical and topographic factors, while the role of rainfall duration is seldom considered within a process-based approach. To investigate the effect of different climate drivers on slope stability, we developed a modeling framework that accounts for the variability of extreme rainfall rate with the duration of rainfall events. The slope stability component includes the key characteristics of the soil mantle, i.e., angle of shearing resistance, void ratio, and specific gravity of solids. Hillslope hydrology is modeled by coupling the conservation of mass of soil water with the Darcy's law used to describe seepage flow. This yields a simple analytical model capable of describing combined effect of duration and intensity of a precipitation episode in triggering shallow landslides. Dimensionless variables are introduced to investigate model sensitivity. Finally, coupling this model with the simple scaling model for the frequency of storm precipitation can help in understanding the climate control on landscape evolution. This leads to predict the temporal scale of hillslope evolution associated with the occurrence of shallow landslides. Model application is shown for the Mettman Ridge study area in Oregon, United States.
Röthlisberger G (1991), "Chronik der Unwetterschäden in der Schweiz", Berichte der Eidgenössichen Forschungaanstalt für Wald, Schnee und Landschaft. Vol. 330, pp. 122.
Abstract: Der Bericht informiert über 2256 Schadenereignisse aus der Zeit von 563 bis 1988. Er beschränkt sich auf Schäden, die durch Gewitter, Dauerregen und Schneeschmelze verursacht wurden.
Im ersten Teil werden Methoden und Kriterien erläutert. Ausmass, Ursache, Art und jahreszeitliche Verteilung der Schadenfälle werden statistisch ausgewertet. In chronologischen Jahrhundert-Überblicken werden Klima, extreme Wetterjahre und katastrophale Ereignisse beschrieben. Der zweite Teil schildert in chronologischer Reihenfolge 261 schwere Unwetterereignisse. Schadenkarten und Bilder sowie ein umfangreiches Literaturverzeichnis ergänzen die Arbeit. Hinweise über Schaden kosten, Prognosen und Massnahmen runden den Bericht ab.
Rowlands KA, Jones LD and Whitworth M (2003), "Landslide Laser Scanning: a new look at an old problem", Quarterly Journal of Engineering Geology and Hydrogeology., May, 2003. Vol. 36, pp. 155-157.
Abstract: An essential part of the study of any landslide problem is the development of a 3-D conceptual model of the landslide and its surroundings. Traditionally this has been done by pen and paper during a walk-over geomorphological survey (Forster 1989) ideally with pits and boreholes to give subsurface information. More recently aerial photographs and aerial ortho-photographs have aided the surface assessment and geophysical surveys have added to the understanding of the third dimension. A more detailed quantitative model could be achieved by accurate ground surveying by EDM, theodolite and level. However, this is time consuming and a high degree of surveying expertise is necessary for an accurate result where small movements might need to be monitored. More recently ‘total station’ surveying equipment has increased the speed at which this process can be completed. However, the advent of affordable semiautomated laser scanners and accurate differential GPS technology has opened up a new opportunity in rapid landslide modelling.
Rubin DM (2004), "A simple autocorrelation algorithm for determining grain size from digital images of sediment", Journal of Sedimentary Research., January, 2004. Vol. 74(1), pp. 160-165.
Abstract: Autocorrelation between pixels in digital images of sediment can be used to measure average grain size of sediment on the bed, grain-size distribution of bed sediment, and vertical profiles in grain size in a cross-sectional image through a bed. The technique is less sensitive than traditional laboratory analyses to tails of a grain-size distribution, but it offers substantial other advantages: it is 100 times as fast; it is ideal for sampling surficial sediment (the part that interacts with a flow); it can determine vertical profiles in grain size on a scale finer than can be sampled physically; and it can be used in the field to provide almost real-time grain-size analysis. The technique can be applied to digital images obtained using any source with sufficient resolution, including digital cameras, digital video, or underwater digital microscopes (for real-time grain-size mapping of the bed).
von Ruette J, Papritz A, Lehmann P, Rickli C and Or D (2011), "Spatial statistical modeling of shallow landslides-Validating predictions for different landslide inventories and rainfall events", Geomorphology., October, 2011. Vol. 133(1-2), pp. 11-22.
Abstract: Statistical models that exploit the correlation between landslide occurrence and geomorphic properties are often used to map the spatial occurrence of shallow landslides triggered by heavy rainfalls. In many landslide susceptibility studies, the true predictive power of the statistical model remains unknown because the predictions are not validated with independent data from other events or areas. This study validates statistical susceptibility predictions with independent test data. The spatial incidence of landslides, triggered by an extreme rainfall in a study area, was modeled by logistic regression. The fitted model was then used to generate susceptibility maps for another three study areas, for which event-based landslide inventories were also available. All the study areas lie in the northern foothills of the Swiss Alps. The landslides had been triggered by heavy rainfall either in 2002 or 2005. The validation was designed such that the first validation study area shared the geomorphology and the second the triggering rainfall event with the calibration study area. For the third validation study area, both geomorphology and rainfall were different. All explanatory variables were extracted for the logistic regression analysis from high-resolution digital elevation and surface models (2.5 m grid). The model fitted to the calibration data comprised four explanatory variables: (i) slope angle (effect of gravitational driving forces), (ii) vegetation type (grassland and forest: root reinforcement), (iii) planform curvature (convergent water flow paths), and (iv) contributing area (potential supply of water). The area under the Receiver Operating Characteristic (ROC) curve (AUC) was used to quantify the predictive performance of the logistic regression model. The AUC values were computed for the susceptibility maps of the three validation study areas (validation AUC), the fitted susceptibility map of the calibration study area (apparent AUC: 0.80) and another susceptibility map obtained for the calibration study area by 20-fold cross-validation (cross-validation AUC: 0.74). The AUC values of the first and second validation study areas (0.72 and 0.69, respectively) and the cross-validation AUC matched fairly well, and all AUC values were distinctly smaller than the apparent AUC. Based on the apparent AUC one would have clearly overrated the predictive performance for the first two validation areas. Rather surprisingly, the AUC value of the third validation study area (0.82) was larger than the apparent AUC. A large part of the third validation study area consists of gentle slopes, and the regression model correctly predicted that no landslides occur in the flat parts. This increased the predictive performance of the model considerably. The predicted susceptibility maps were further validated by summing the predicted susceptibil