Social vulnerability assessment of landslide disaster based on improved TOPSIS method: Case study of eleven small towns in China

Abstract

• Constructing evaluation index system of social vulnerability of small towns in China. • Exploring the spatial differences of social vulnerability landslide disaster areas. • Risk perception and social structure are the two key factors of social vulnerability in landslide disaster areas. • It provides a case and method reference for structural and non-structural disaster prevention & mitigation.a. There are few studies on the social vulnerability of small towns in landslide disaster areas. The occurrence of geological disasters will directly threaten the local socioeconomic growth, it is particularly important to identify vulnerable areas and populations by using the social vulnerability index system. Eleven small towns of landslide areas after Wenchuan earthquake were taken as examples, based on 863 questionnaires and statistical data, this study established a new comprehensive evaluation index system of social vulnerability evaluation in landslide areas, and conducted quantitative evaluation by using the improved TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) model, the social vulnerability index was adopted to compare, classify and rank the social vulnerability levels in townships. The empirical results indicate that the social vulnerability showed the characteristics of regional heterogeneity, most towns showed a high or medium level of social vulnerability. Only Yingxiu showed a low level of social vulnerability, Shuimo presented the highest evaluation score of social vulnerability in eleven towns, the inter-group difference between these two towns is 0.286. Risk perception is an important factor affecting social vulnerability in landslide areas, involving disaster awareness, disaster cognitive approach, and community publicity. Additionally, social structure is another key factor affecting these areas based on the scores of the top three areas with the highest social vulnerability, including disaster prevention facilities, residents' income, and infrastructure accessibility. The index system can evaluate the social vulnerability scientifically in landslide areas, it can be used for urban disaster management and socioeconomic development in geological disaster areas.