Disaster-Generating Environment And Disaster-Causing Factors Of Landslide Geological Disaster In Pingbian County,Yunnan Province

Pingbian County is located in the southeast of Honghe Prefecture.There are high mountains and valleys crisscross in the county,and the river system is well developed,with the landform of "four rivers,three beams and six slopes".The complex geological environment provides good conditions for the development of landslide geological disasters.This paper,by using high resolution satellite remote sensing data interpretation the screen edge of landslide geological hazards in the county data,using statistical methods,the adjacent analysis method,the density of nuclear analysis method and standard deviation ellipse analyses the scale characteristics of the landslide in the area,number and spatial distribution characteristics,summarizes the development of the landslide in the study area subsequently environment.Based on the Arc GIS platform,the research area was divided into 30m×30m cell grid,and the sensitivity analysis of the selected disaster-causing factors was carried out by using the information content model.The main achievements are as follows:(1)Based on the interpretation results and the number of landslide geological hazards obtained from field verification,the scale and quantitative characteristics of the development of landslide geological hazards in Pingbian County were found out.The spatial characteristics of landslide geological hazard distribution in Pingbian County were analyzed by using the nearest neighbor analysis,kernel density analysis and standard deviation ellipse.(2)The distribution characteristics of landslide geological hazards in Pingbian County are summarized.From the perspective of scale,the landslide geological hazards developed in pingbian county are all small and medium-sized ones,among which 78 are small and 16 are medium ones.Among the seven townships in Pingbian County,Heping Town has the largest number of landslide geological disasters,while Baiyun Township has the least.From the perspective of space,the geological hazards of landslides in Pingbian County tend to be concentrated and distributed in the middle part of Xinxian Town,the west part of Xinhua Township,the middle part and the northwest part of Heping Town.(3)Based on the analysis of the characteristics of geological and geographical environment and the present development characteristics of landslide geological disaster,the disaster-bearing environment for the development of landslide geological disaster in Pingbian County was found out.(4)Based on the analysis of landslide geological disasters subsequently environment and the forming condition,on the basis of elevation,gradient,slope direction,rainfall,distance from the river,the types of rock mass,fault distance,vegetation coverage and the distance from the road,nine-formative factors such as based on Arc GIS platform,using the information model,to get nine to sensitivity analysis.The results show that the most easy conditions for the development of landslide in the study area are: the elevation of 1200m?2000m;Grade 10 ° to 30 °;The slope is eastward(67.5°?112.5°)and southeast(112.5°?157.5°).Distance from river 0?1800m;The types of rock and soil are loose rock,soft rock and hard rock with soft rock.0?600m away from the fault;Vegetation coverage less than 70%;The distance from the road is 0?1200m.