Abstract:
Regional geological hazard susceptibility assessment is an indispensable part of disaster prevention and mitigation. Taking Ning’er Hani and Yi Autonomous County, Yunnan Province as a research area, using GIS as the technical tool and CF&LR combined model as research method, we constructed an evaluation index system containing 9 evaluation factors based on disaster-causing factors, the disaster-potential, hazard developing environment and regional geological disaster data. We analyzed the relationship between the evaluation index factors and the relative density of the disaster sites, and evaluated and verified the geological disaster susceptibility in the study area. The results show that: ① The sensitivity of the nine evaluation index factors from high to low are as follows, distance from river, distance from fault zone, slope direction, elevation, NDVI, rainfall, slope, rock hardness, distance from road; ② The most geological hazard-prone conditions in the study area are 0~200 m from the river, 0~500 m from the fault zone, southwest slope (202.5° ~ 247.5°), elevation (1450~1900 m), NDVI range of 0 ~ 0.2, rainfall (1458 ~ 1537 mm), slope (30° ~ 35°), soft rock, and distance from Road (0~500 m); ③ The area of extremely high-risk area, high-risk area, middle-risk area and low-risk area accounted for 8.23%, 37.17%, 43.39% and 11.21% of the study area respectively. The distribution of geological disasters in the study area shows a characteristics of less in the north and more in the south, less in the east and more in the west; ④ The results of CF&LR combined model were reasonable, the AUC value is 0.74, and the evaluation result is more accurate.