Research On Comprehensive Vulnerability Assessment Of Community Flood Disasters

Flood disasters,as a type of natural disaster,have the characteristics of high frequency of occurrence and strong destructiveness,which have seriously threatened the residents and economic life of coastal areas.Against the background of global urbanization,countries attach great importance to the research and defense of urban flood disasters,among which vulnerability research is considered an important field of flood control and disaster reduction.In the past,research on disaster vulnerability mainly focused on the causes of disasters,believing that eliminating the causative factors can fundamentally eliminate the occurrence of disasters.However,with the passage of time,research has gradually shifted to the vulnerability of disaster-affected bodies,believing that reducing the vulnerability of disaster-affected bodies is the most direct and effective way to reduce the impact of natural disasters.This article focuses on the relatively novel direction of comprehensive vulnerability assessment of flood disaster communities.Drawing on the progress of domestic and foreign community disaster vulnerability research,this study takes the199 communities(neighborhood committees)in Hongkou District,Shanghai as the disaster-affected bodies.Starting with the relevant attributes of flood disasters,the study uses the HOP model and GIS tools to extract spatial information of urban communities,establishing a spatial information database of the research area.On this basis,using the index system analysis method,the study selects evaluation indicators from three aspects of natural vulnerability,social vulnerability,and comprehensive vulnerability,and assigns weights using the entropy method and principal component analysis method,carrying out a comprehensive vulnerability assessment of flood disasters in Hongkou District,Shanghai.Through spatial analysis of the evaluation results,the spatial and attribute characteristics are revealed.The main research results of this article are as follows:1.Summarizing the research on natural disaster vulnerability,it is found that the current evaluation of natural disaster vulnerability based on the community scale is relatively lacking.Therefore,this study evaluated the natural vulnerability,social vulnerability,and comprehensive vulnerability of flood disasters based on communities(neighborhood committees)as the basic units.Based on previous research and the characteristics of the research area,this study selected the HOP concept model and index system analysis method suitable for evaluating the vulnerability of flood disasters at the community scale.Evaluating flood disaster vulnerability using fine basic spatial units can comprehensively understand the characteristics of flood disaster vulnerability in different areas of the city,especially high-density cities,which can help cities to better manage flood disaster risks and take corresponding response measures,and can also provide a reference for the evaluation of natural disaster vulnerability in other highdensity cities.2.This study takes the Hongkou District of Shanghai as an example,selecting 199communities(neighborhood committees)in Hongkou District as the research units,using GIS technology to extract spatial information of communities,and conducting spatial analysis of the vulnerability evaluation results based on this.The results show that the overall natural vulnerability of flood disasters in Hongkou District exhibits a distribution pattern of low in the north,high in the middle,and low in the south.The main reason for this may be that the southern part is closer to the Huangpu River,with lower terrain,high transportation convenience,and dense buildings,which leads to relatively higher flood disaster risks in the south.The overall social vulnerability of flood disasters in Hongkou District exhibits a distribution pattern of high in the north and low in the south.This may be related to the higher population density and denser buildings in the southern part of Hongkou District,but relatively lagging infrastructure construction and weak community management organization capacity.In addition,there are many parks,green spaces,and protected areas in the south,which also limit the residential areas of southern residents and lead to relatively lower social vulnerability of flood disasters.3.In evaluating the comprehensive vulnerability of flood disasters,three methods were used to analyze the results of comprehensive vulnerability under different weights:average weight,natural vulnerability dominance,and social vulnerability dominance.Through comparative analysis of comprehensive vulnerability under different weights,it is summarized that under the condition of natural vulnerability dominance,the northern region is more vulnerable to natural vulnerability than the southern region.This means that the northern region is more susceptible to the impact of natural disasters,but due to the lower natural vulnerability of communities,the overall vulnerability is relatively low.Under the condition of social vulnerability dominance,the southern region is more socially vulnerable than the northern region.This means that the social vulnerability of the southern region is higher,but the overall vulnerability evaluation result is higher.This indicates that the evaluation result of comprehensive vulnerability is affected by the weight of different types of vulnerabilities,and suitable weights need to be selected according to specific situations.