Research On Resilience Assessment Of Urban Flood Disaster Based On Immunology

In recent years,as urbanisation continues,the original hydrological cycle of cities has been severely disrupted and "urban sea-gazing" has become a common phenomenon.As one of the most flood-prone countries in the world,China’s resilience to floods is clearly lacking.Therefore,we should start with the assessment of urban flood resilience,identify its shortcomings and countermeasures,and move from "passive fire-fighting" to "active immunisation".This study defines the connotation of urban flood resilience based on immunological theory,and constructs an urban flood resilience assessment model based on the proposed "pressure-resilience-adaptability" conceptual framework using the entropy-TOPSIS method.The study aims to identify the overall level,spatial distribution characteristics and main influencing factors of urban flood resilience in the Yangtze River Delta urban agglomeration,and propose optimization strategies accordingly,with the aim of providing some reference for urban flood disaster management.The thesis has three parts.(1)Constructing an urban flood disaster resilience assessment model based on immunological theoryBased on the similarity between the role of immunity in sustaining human health and the resilience mechanism,the pathogenic,non-specific and specific immunity of the immune system are corresponding to the stress resilience,resistance resilience and adaptability resilience of urban flood disaster resilience,so as to establish an urban flood disaster resilience assessment index system and construct an urban flood disaster resilience assessment model by applying the entropy-weight-TOPSIS method.(2)Assessing the resilience level of urban flooding in the Yangtze River Delta city cluster and identifying its main influencing factorsThe results show that the urban flooding resilience of the Yangtze River Delta urban agglomeration is generally at a medium level,with a decreasing spatial pattern of "core-edge",with Shanghai,Hangzhou and Nanjing as the core cities.The spatially decreasing "core-edge" pattern with Shanghai,Hangzhou and Nanjing as the core,and the spatially significant differences in the resilience levels of each dimension.The results show that adaptive resilience is the key dimension to improve the resilience level of urban flooding.The natural population growth rate,average elevation,the proportion of tertiary industry value added to GDP,the length of drainage pipes per10,000 people,the number of public buses and trams per 10,000 people,and the number of hospital and sanatorium beds per 10,000 people are the main influencing factors.(3)Proposing specific strategies for optimising the resilience of cities to floodingThe basic idea of the optimisation strategy to improve the resilience of cities to floods is to reduce the negative effects of "stressors",strengthen the robustness of the urban system and enhance the immunity of the subject,so as to improve the overall resilience of the city.This study has two innovations: firstly,it constructs an immunology-based model for urban flood resilience assessment,which provides a scientific method for urban flood disaster management.Second,it proposes a specific optimization strategy to improve the resilience of urban flooding,which provides intellectual support for urban flooding disaster management.