Social vulnerability assessment of geological hazards based on entropy method in Lushan earthquake-stricken area

The geological disasters that occurred frequently following the Lushan earthquake affected the resilience of people living in the affected areas. This study selected 21 counties (county-level cities and districts) in Lushan earthquake-stricken area as the research object. Eight indices extracted from remote sensing image data, statistical data, and field investigations are used as analysis indicators. The eight indices are population density, building coverage, road density, number of hospitals per 10,000 persons, number of welfare institutes per 10,000 persons, number of villager committees per 10,000 persons, mobile users’ proportion at year’s end, and number of schools per 10,000 persons. Using Excel and ArcGIS software, the assessment based on entropy value method comprehensively evaluates the social vulnerability to geological hazards of 21 counties. The social vulnerability of study area is divided into five stages (from lowest to highest): areas with the lowest social vulnerability, namely Shimian County and Kangding County; areas with the low social vulnerability, namely Ebian Yi Autonomous County, Tianquan County, Jinkouhe District, Yingjing County, Luding County, and Baoxing County; areas with medium social vulnerability, which are Hongya County, Hanyuan County, Ganluo County, and Lushan County; areas with high social vulnerability, namely Dayi County, Yucheng District, and Emeishan City; and areas with the highest social vulnerability which are Pujiang County, Mingshan County, Qionglai City, Dongpo District, Danling County, and Jiajiang County. The classification of the results can serve as a guide to disaster resilience planning and reconstruction in relation to geological hazards.