Databases and Geographic Information Systems for Medium Scale Landslide Hazard Evaluation: An Example from Typical Mountain Watershed in Nepal

The landslide distribution data extracted from aerial photos, and thematic databases derived from maps (e.g., slope gradient, geology, land use/cover) were used for modeling landslide hazard, at a medium scale (1:25,000 – 1:50,000), using GIS. The site characteristics of landsliding were evaluated using multivariate statistical (Quantification Scaling Type II) and univariate statistical (Failure Rate) methods. Two failure rate analyses were carried out. Three hazard maps were produced from the results of the analyses. The spatial agreements between three hazard maps were evaluated. The hazard maps produced from different methods agreed up to 60 percent to 80 percent depending on whether the study area is classified into four hazard classes or two hazard categories, respectively.

• INTRODUCTION

• ACQUISITION OF DATA BASES AND GIS DATA LAYERS

• METHODS OF ANALYSIS

• ANDSLIDE HAZARD MAPPING

• PATIAL AGREEMENT BETWEEN THE HAZARD MAPS

• DISCUSSIONS AND CONCLUSIONS

• Acknowledgments

• References