长江三角洲城市群洪涝灾害脆弱性评估及影响因素分析

Vulnerability Assessment and Influencing Factors Analysis of Urban Flood Disaster in Yangtze River Delta City Cluster

长江三角洲城市群人口、财产、基础设施高度密集,暴雨洪涝灾害带来的影响越来越大,对该区域城市洪涝灾害脆弱性进行评估是保障长江三角洲区域一体化、可持续发展的基础。以长江三角洲城市群中心区27个城市为研究对象,基于超效率DEA模型,将洪涝灾害脆弱性看作一个负面“生产活动”,构建城市洪涝灾害脆弱性评估模型,在分析脆弱性空间分异特征的基础上确定该地区城市洪涝灾害脆弱性的主要影响因素。结果显示:从整体上看,长江三角洲城市群洪涝灾害脆弱性水平差异较大,安徽及浙江远高于江苏和上海,其中,上海的洪灾脆弱性最低;从空间上看,脆弱性分布有明显的地域集聚特征,脆弱性高的城市分布在浙江东南沿海和安徽南部丘陵地区;降雨量、城市发展水平及基础设施的完善性等因素对城市洪涝灾害脆弱性影响显著。

The population,property and infrastructure are highly concentrated in Yangtze River Delta City Cluster,which makes it more and more sensitive to storm and flood.Therefore,the assessment of vulnerability to flood disasters is the basis for ensuring regional integration and sustainable development of the Yangtze River Delta.In this paper,27 central cities in the Yangtze River Delta are selected.Super efficiency DEA model is applied to build urban flood vulnerability assessment model,in which flood vulnerability is considered as a negative“production”.And then the spatial differentiation analysis is carried out by using the Moran’s I and Theil index.Finally,the Tobit regression model is used to analyze the influencing factors of urban flood vulnerability.The results show that the overall urban flood vulnerability of Yangtze River Delta City Cluster varies greatly.Vulnerability in Anhui and Zhejiang is much higher than that in Jiangsu and Shanghai.From the spatial perspective,the vulnerability distribution of urban flood disasters in the Yangtze River Delta City Cluster presents obvious regional aggregation characteristics.The cities with high vulnerability are distributed in the southeast coastal area of Zhejiang and southern hilly area of Anhui.Rainfall,urban development level,and the supporting infrastructure have significant impacts on the vulnerability of urban floods.The results reveal the spatial and temporal differences of flood resilience within the Yangtze River Delta City Cluster,as well as the influence of climate factors,urban hydrology and infrastructure on urban flood disaster vulnerability.It can provide reference for improving resilience to flood disaster and promoting integrated disaster prevention and reduction.