Use of LIDAR‐derived images for mapping old landslides under forest

Large, deep‐seated landslides are common features in the Flemish Ardennes (Belgium). As most of these old (>100 years) landslides are located under forest in this hilly region, aerial photograph interpretation is not an appropriate landslide mapping method. This study tested the potential of LIDAR (Light Detection and Ranging) images for mapping old landslides under forest. Landslide inventory maps were created for a 125 km2 area by applying the expert knowledge of seven geomorphologists to LIDAR‐derived hillshade, slope and contour line maps in a GIS environment. Each of the seven LIDAR‐based landslide inventories was compared (i) with the other six, (ii) with a detailed field survey‐based inventory, and (iii) with a comparable study in which topographic data were extracted from a topographical map. The combination of the percentage of field landslides indicated by an expert and the percentage of positional discrepancies (expressed in terms of positional mismatch) were used to evaluate the quality of the LIDAR‐based inventory maps. High‐quality LIDAR‐derived landslide inventory maps contain more than 70 per cent of the landslides mapped during the field survey, and have positional discrepancies smaller than 70 per cent when compared with the field survey‐based inventory map. Four experts and the combination map of all experts satisfied these criteria. Together the seven experts indicated all landslides mapped in the field. Importantly, LIDAR enabled the experts to find ten new landslides and to correct the boundaries of eleven (of the 77) landslides mapped during the field survey. Hence, this study showed that large‐scale LIDAR‐derived maps analysed by experienced geomorphologists can significantly improve field survey‐based inventories of landslides with a subdued morphology in hilly regions. Copyright © 2006 John Wiley & Sons, Ltd.

[1]  D. Varnes,et al.  Landslide types and processes , 2004 .

[2]  Iaeg Commission on Landslides.  Suggested nomenclature for landslides , 1990 .

[3]  P. Reichenbach,et al.  GIS techniques and statistical models in evaluating landslide hazard , 1991 .

[4]  P. Reichenbach,et al.  Gis Technology in Mapping Landslide Hazard , 1995 .

[5]  A. C. Seijmonsbergen,et al.  Comparing Landslide Hazard Maps , 1999 .

[6]  P. Reichenbach,et al.  Comparing Landslide Maps: A Case Study in the Upper Tiber River Basin, Central Italy , 2000, Environmental management.

[7]  William Eugene Carter,et al.  Airborne laser swath mapping shines new light on Earth's topography , 2001 .

[8]  Fausto Guzzetti,et al.  Impact of mapping errors on the reliability of landslide hazard maps , 2002 .

[9]  C. Wills,et al.  Comparing Landslide Inventories: The Map Depends on the Method , 2002 .

[10]  José Luís Zêzere,et al.  Landslide susceptibility assessment considering landslide typology. A case study in the area north of Lisbon (Portugal) , 2002 .

[11]  Veerle Vanacker,et al.  Linking hydrological, infinite slope stability and land-use change models through GIS for assessing the impact of deforestation on slope stability in high Andean watersheds , 2003 .

[12]  David J. Harding,et al.  High-resolution lidar topography of the Puget Lowland, Washington - A bonanza for earth science , 2003 .

[13]  A. Demoulin,et al.  On the origin of late Quaternary palaeolandslides in the Liège (E Belgium) area , 2003 .

[14]  Yong Wang,et al.  Utilizing DEMs derived from LIDAR data to analyze morphologic change in the North Carolina coastline , 2003 .

[15]  M. Hodgson,et al.  An evaluation of LIDAR- and IFSAR-derived digital elevation models in leaf-on conditions with USGS Level 1 and Level 2 DEMs , 2003 .

[16]  M. Whitworth,et al.  Landslide Laser Scanning: a new look at an old problem , 2003, Quarterly Journal of Engineering Geology and Hydrogeology.

[17]  M. Eeckhaut,et al.  Characteristics and spatial distribution of large landslides in the Flemish Ardennes (Belgium) (with 12 figures and 3 tables) , 2003 .

[18]  William H. Schulz,et al.  Landslides mapped using LIDAR imagery, Seattle, Washington , 2004 .

[19]  J. McKean,et al.  Objective landslide detection and surface morphology mapping using high-resolution airborne laser altimetry , 2004 .

[20]  M. Eeckhaut,et al.  The effectiveness of hillshade maps and expert knowledge in mapping old deep-seated landslides , 2005 .

[21]  M. Bauer,et al.  Airborne laser scanning for riverbank erosion assessment , 2005 .

[22]  L. Hurni,et al.  Remote sensing of landslides: An analysis of the potential contribution to geo-spatial systems for hazard assessment in mountainous environments , 2005 .

[23]  D. J. Chadwick,et al.  Analysis of LiDAR-derived topographic information for characterizing and differentiating landslide morphology and activity , 2006 .