Study On The Temporal And Spatial Variation Of Flood Disaster Resilience In Chaohu Basin

Since twenty-first Century,with the global change,the contradictions gradually deepening between social development and environmental resources,the frequent occurrence of natural disasters,the sustainable development of human society has been seriously threatened.Increasing natural disaster resilience is one of the important ways to deal with climate change and natural disasters,and has received more and more attention.Flood disaster is one of the most serious natural disasters at all scales,not only in the world,but also in china,as well as in the Chaohu Basin.Taking the Chaohu Basin as a case,based on the summary of the research of natural disasters disaster resilience on the comprehensive analysis of the impact of the five dimensions of nature,society,economy,technology,management,the evaluation index system of flood disaster disaster resilience in the Chaohu Basin was constructed by selecting 14 indicators.Taking into account the factors affecting flood disaster resilience are numerous and interrelated,Firstly,the DEMATEL method is used to analyze the relationship between the influence factors of flood disaster resilience in the Chaohu Basin,identify and distinguish these factors,which can provide decision-making basis for the quick finding of the factors that need to be improved;Secondly,the ANP analysis method is used to calculate the weight of the non independent index,and then the flood disaster resilience of the Chaohu Basin in 2000,2005,2010 were evaluated;Finally,the temporal and spatial variation of flood disaster resilience was analyzed based on the evaluation results of flood disaster resilience in the three years.The results showed that:(1)from the perspective of exerting influence,natural dimension,social dimension,economic dimension of the first class indexes,and terrain influence degree,population density,GDP density of the second class indexes have significant influence on other factors of the corresponding level;from the perspective of being affected,social dimension,economic dimension of the first class indexes,and rural per capita net income,average financial income,GDP density of the second class indexes are the most easily affected by other factors of the corresponding level.Need to focus on the difficulties level of these factors to improve.(2)Natural dimension,economic dimension,social dimension of the first class indexes,and GDP density,population density and proportion of urban and rural population of the second class indexes are at the core position of the relationship network of the corresponding level.(3)Causal factor of the first class indexes is only natural dimension,and 7causal factors in the second class indexes,which involve three dimensions of natural dimension,social dimension and economic dimension,and include all the factors of natural and social dimension.There are 4 reason-oriented factors in the first class indexes,which are social dimension,administrative dimension,economic dimension,technical dimension in descending order,7 reason-oriented factors in the first class indexes,involving economic,technical and administrative dimensions,and including all factors of technical dimension and administrative dimensions;Compared to causal factor,the improvement of reason-oriented factor can directly improve the level of regional flood disaster resilience.(4)Flood disaster resilience indexes in most areas of the Chaohu Basin were increasing in all dimensions and integration,and flood disaster resilience index of economic dimension in all areas were growing,however,the distribution pattern of flood disaster resilience in the Chaohu Basin had no major changes,showing that the low value areas were in the southeast and the west lakeside area,the high value existed in the southwest and northern regions.(5)The influence factors of economic dimension had the most positive impacts on the growth of flood disaster resilience,but the influence factors of natural dimension played negative roles.(6)the resilience index of each administrative region was increasing,but the relative position of each year was not changed much,the resilience index of Hefei City was always the highest,Wuwei County was always the lowest;The growth rate of the resilience index in each administrative region in 2005-2010 increased faster than that in 2000-2010,the average growth rate of Hefei City was the highest in ten years,Feidong County and Feixi County had higher rates,Wuwei County,He County owned a medium speed,the growth rates of Shucheng County,Chaohu City,Lujiang County,Hanshan County were low.(7)The distribution area of the highest level resilience was decreasing,which was mainly distributed in the north and central part of the basin at last,the flood disaster resilience here grew significantly faster than the growth rates of other regions,There were no major changes in the distribution area of the middle level resilience and below it,the main change was that the distribution area of the highest level resilience was transferred to the higher level resilience.(8)The resilience levels of Hefei City,Feixi County,Wuwei County,Hanshan County were unchanged,respectively,in the highest level,higher level,the lowest level,higher level;Shucheng County,Lujiang County,and He county,respectively,from the highest level down to a higher level,the middle level down to a lower level,the middle grade down to a lower level;moreover,Feidong County rose from higher-level to the highest level,Chaohu City rose from middle level to higher level and then down to the middle level.(9)There were no large changes in the landscape fragmentation degree and morphological complexity of the middle level resilience and below it,the distribution of the higher and highest level resilience become more compact and concentrated,and their forms become more regular;The transfer route of landscape centroid indicated that on the whole,the resilience landscape distribution of middle and above level gone back to the northwest region.In particular,the distribution of the highest resilience landscape had the most obvious change,and the distribution pattern of the lower and the lowest level resilience landscape changed little.