Risk Analysis of Geological Disasters in Southwest China

Abstract

In this study, four provinces (cities) in southwest China were taken as the study area, and eight risk evaluation indexes were selected to construct the evaluation index grading system, including elevation, slope, relative elevation, soil erosion, annual precipitation, NDVI, land use and population. The analytic hierarchy process was used to obtain the weight coefficients of each evaluation index, a geological hazard risk assessment model for the study area was established, and spatial calculation and visual expression were performed by ArcGIS. The results shows that the area of moderate-risk is the largest, accounting for 37.46% of the total area; followed by the low-risk area, which accounts for 23.89%; the proportions of high-risk areas and extremely high-risk areas are 23.59% and 15.07%.According to the risk analysis results, the geological disasters area with high risk include southwest Yunnan, central Sichuan, southwest Guizhou and northeast Chongqing.