GIS-based Assessment of Vulnerability to Landslide Hazards in Lushan Earthquake-stricken Areas

Abstract

This paper establishes a GIS-based system of vulnerability assessment to landslide hazard for Lushan earthquake-stricken areas. By taking these areas as the study area and ArcGIS 9.3 Software as the platform; with GIS Grid Technology and adopting Contributing Weight Overlay Model, we extract 6 vulnerability assessment indexes including population, economic, and road densities, building and forestland coverage, and landslide hazard affected areas. Besides, it compiles vulnerability zoning maps to landslide hazard by means of Natural Breaks Classification. The results show that the high, middle, and low vulnerability zones occupy 17.93%, 61.54%, and 20.53% of the total area respectively. The vulnerability level is positively correlated with the former four indexes; while negatively with the forest coverage. The distribution of landslide hazard affected areas is closely correlated to the intensity of human engineering activities. Contrasted with the field survey ones, the GIS-based zoning results of vulnerability to landslide hazard basically correspond with the actual situation of Lushan earthquake-stricken areas, and can thus be applied in guiding the post-disaster restoration and construction, settlement relocation, and population distribution readjustment.