GIS-based risk assessment of flood disaster in the Lijiang River Basin

This study is designed to provide a scientific reference for the establishment of rainstorm and flood disaster prevention system in Guilin region and improve the risk assessment of rainstorm and flood disasters. To realize the goal, a flood risk evaluation model is established by weight analysis methods including the entropy weight method and the analytic hierarchy process from 3 aspects, i.e., risk of disaster causing factors, sensitivity of disaster-pregnant environment and vulnerability of disaster bearing body.

Based on GIS and flood disaster risk assessment model, this study found that the risk level of flood disaster causing factors in the Lijiang River basin was decreasing from north to south. The area of high-risk areas accounted for 21.29%, which was 3108.47 km2; The stability level of the disaster prone environment generally shows a decreasing trend from the surrounding mountains to the plains. Low stability and low stability areas mostly exist in low-lying areas around the Lijiang River, with an area of 4218.63 km2, accounting for 28.69%. The vulnerability level of hazard bearing bodies is generally at a low level, and the area with a high level is 246.96 km2, accounting for only 1.69%.