Research On Spatial Temporal Pattern Evolution And Barrier Factors Of Urban Vulnerability In Zhongyuan Urban Agglomeration

With the increasing global climate change and the increasing severity of urban diseases,urban vulnerability,as a new branch of traditional vulnerability research,has become one of the hot issues in the study of sustainable urban development.Urban vulnerability provides a new research perspective for the study of the coupling mechanism of man-land systems and the coordinated development of regional socioeconomic systems.It is an important research content and basic scientific knowledge system for sustainable development studies in the global region.As a densely populated space where population economics and society are closely linked and interacting with each other,cities in urban agglomerations are faced with a series of urban disease problems such as environmental pollution,depletion of resources and unemployment.Urban agglomerations have typical characteristics of urban vulnerability.Zhongyuan Urban Agglomeration is an important region that promotes the rise of the central region and the development of the central and western regions through the radiation.Through the analysis of its urban vulnerability,it discusses the obstacles that affect the accumulation of urban vulnerability,and prevents or prevents the outbreak of chronic urban diseases.The sustainable development of urban agglomeration and the construction of new urbanization all have important theoretical and practical significance.The paper takes the 30 provincial cities of Zhongyuan Urban Agglomeration as the case area,defines the concept of urban vulnerability,constructs the index system of urban vulnerability assessment,uses the entropy method to comprehensively measure the urban vulnerability of Zhongyuan Urban Agglomeration,and Using spatial analysis techniques such as coefficient of variation,GIS spatial classification,and ESDA to analyze the temporal and spatial evolution of vulnerability subsystems and comprehensive vulnerability systems of urban agglomerations.Finally,the obstacle degree model was used to quantify the types of comprehensive vulnerability of urban agglomerations,and the main obstacles to the reduction of vulnerability of each city were revealed according to the degree of obstacles of each index.The conclusion of the paper is as follows.Firstly,Temporal and spatial evolution of urban vulnerability in Zhongyuan Urban Agglomeration.In terms of time series,from 2005 to 2015,the vulnerability of thesocial,economic,resource,and environmental subsystems,and the urban vulnerability composite system of each city in the Central Plains urban agglomerations tended to fluctuate and decline,but there were differences in each stage,2005-2011,in a period of rapid decline,2011-2015 is a steady decline.From 2005 to 2015,the change trajectory of the vulnerability index of resource-environment subsystems is more complex than that of social vulnerability and economic vulnerability,and the magnitude of reduction is smaller than that of social and economic subsystems.In terms of spatial distribution,the urban fragility pattern of Zhongyuan Urban Agglomeration has undergone significant changes,and the overall extent has dropped significantly,except for Huaibei,Bozhou,Suzhou in northern Anhui and Hebi,North of Henan is in a medium fragile state,and the rest of the cities are in a low or lower fragile state,has formed a wide range of low fragile area.Secondly,Spatial correlation characteristics of urban frailty in Central Plains urban agglomeration.There is a spatial agglomeration phenomenon in the urban fragility of the Central Plains urban agglomeration,and the agglomeration effect is weakening.From the LISA significance agglomeration chart,from 2005 to 2015,the significant HH district is always distributed in some cities in the southeastern part of the urban agglomeration.The number of districts is decreasing,and the significant LL district is reduced from 5 to 2 in 2015,Bengbu has always belonged to the significant LH area,significant HL area evolved from the original absence to 1 in 2015.From 2005 to 2015,the spatial correlation types of urban vulnerability are balanced and evolved from HH,LL to HH,LL,HL,and LH types of regions.Thirdly,Obstacle factors affecting urban vulnerability of Zhongyuan Urban Agglomeration.Different barriers affect the degree of vulnerability of cities in the Zhongyuan Urban Agglomeration.Combining the size of obstacles and the frequency of appearance of the first five obstacles can be found:the main obstacles to economic system indicators that affect the vulnerability of the Zhongyuan Urban Agglomeration are economic extroversion,financial self-sufficiency,and full-time equivalents for personnel in(R&D)activities;The main barriers to social system indicators affecting urban vulnerability reduction are population natural growth rate and the number of internet users owned by tens of thousands of people;The main obstacles to the indicators of the impact of urban vulnerability on resource-environmental systems are 10,000 yuan GDP electricity consumption,industrial effluent discharge per unit area,and industrial dust emissions per unit area.Fourthly,Risk control and avoidance measures of urban vulnerability in Zhongyuan Urban Agglomeration.Due to the different obstacles in reducing the vulnerability of cities,the related departments should establish the dynamic management system of obstacle factors,carry out strict and scientific control management on the barriers to reduce the decline of urban vulnerability,and realize the risk control of the obstacle factors through continuous inspection,continuous follow-up,step management and evasion,thus improving the overall level of urban development,and promoting the construction of a healthy economic development type,social stability and progress,resource saving and environment-friendly cities.The paper focuses on the comprehensive research and dynamic evolution of the factors affecting urban vulnerability.Through the evaluation of the vulnerability degree of cities,the analysis of the temporal and spatial evolution characteristics of urban vulnerability,and the identification of the obstacles that affect the vulnerability of cities,the paper puts forward some countermeasures to avoid urban vulnerability.At the same time,a preliminary exploration of the research index system of vulnerability in general cities is made,which enriches the contents and theories of vulnerability research.