Study On The Spatial-temporal Development Quality Evaluation And Influencing Factors Of Chengdu-chongqing Urban Agglomeration

Urban agglomeration is the outcome of the development of China's new industrialization and new urbanization to a higher stage.China's urbanization has entered a stage of rapid development.According to the National Bureau of Statistics,China's urbanization level has reached 56.8% in 2016.Rapid urbanization determines China's future and the progress of urbanization in the world.The report of the 19 th National Congress of the Communist Party of China clearly stated that “we should build the urban structure of coordinated development of large and medium cities and small towns which focuses on urban agglomeration.'' Urban congestion,pollution and other problems are becoming more and more prominent owing to the rapid urbanization and the development of small and medium-sized cities is lagging behind.Nowadays,the new urbanization strategy with the theme of improving quality and increasing efficiency requires to improve the quality of urban development fundamentally.Under the background of promoting the new urbanization strategy,it is of great practical and strategic significance to accelerate the construction of Chengdu-Chongqing Urban Agglomeration(CCUA),improve the quality of urban development and strengthen urban and rural integration.Based on the theory of regional economic growth,sustainable development,population migration and aggregation and diffusion,drawing lessons from the domestic and foreign scholars on urban agglomeration development quality evaluation and spatialtemporal distribution,combing development status of CCUA,the paper builds the evaluation system of urban agglomeration development from five aspects: population,economy,public services,environment and urban and rural integration.The paper evaluates the development quality of CCUA in 2005,2010 and 2015 by combining the methods of Analytic Hierarchy Process and Entropy Weighting Model.Based on the results of evaluation,the author analyzes the spatial correlation characteristics of CCUA by adopting the Spatial Autocorrelation Model.Besides,based on urban spatial economic connection model,urban spatial flow model and ArcGIS radial research module,the paper analyzes the characteristics of spatial heterogeneity.Finally,the paper explores the influencing factors by adopting spatial measurement model,and the conclusions are as follows:First,the spatial-temporal development quality evaluation of CCUA.(1)From the perspective of time differentiation,the development quality of population,economy,public service and ecological environment is rising,and that of urban and rural integration is decreasing.(2)From the perspective of spatial differentiation,the differentiation characteristics of dimensional hierarchy are obvious,but the changes are not significant.The quality of population development in Chongqing main urban areas and surrounding districts is higher than that of Sichuan prefecture-level cities.Regions with higher quality of economic and public service development are consistent with those of overall urban agglomeration development.The development quality of ecological environment in Chongqing is better than that in Sichuan.The urban-rural gap of Sichuan prefecture-level cities is bigger than that of Chongqing.The ecological environment development level of the regions with higher economic development level is lower,while the ecological environment development level of the regions with lower economic development level is higher.Second,the spatial-temporal differentiation characteristics of development quality of CCUA and its influencing factors.(1)From the perspective of global spatial autocorrelation,the spatial distribution of the comprehensive index of urban development quality of CCUA has significant positive spatial correlation.High level and high level regions perform spatial agglomeration,and low level and low level regions perform spatial agglomeration.(2)From the perspective of local spatial autocorrelation,the urban development quality and aggregation degree of prefecture-level cities are significantly different.(3)The characteristics of hierarchical heterogeneity,structural heterogeneity and functional heterogeneity of CCUA are: the main factor that influences the structural heterogeneity of CCUA is the spatial distance between the secondary city and the core city,the closer the secondary city to the core city is,the higher its economic development level is,however,distance is not the only determinant;the hierarchical heterogeneity is obvious.It can promote the concentration and diffusion of element flows,but it also has some disadvantages;the functional heterogeneity is complex: the functional heterogeneity of individual city is prominent,the industry's functional similarity is significant,the spatial heterogeneity on innovation is obvious;the spatial heterogeneity and spatial integration of CCUA are two aspects of the contradiction.(4)The influencing factors of spatial-temporal development quality of CCUA are as follows.Household registration system plays an increasingly important role in improving the development quality of CCUA.Economic factors,industrial factors and public service level are playing a declining role in improving the development quality of CCUA.Consumption plays an increasingly important role in improving the development quality of CCUA.Based on this,the author puts forward following policy recommendations for the development of CCUA: first,to accelerate reform of the household registration system and promote equal access to basic public services;second,to develop particular industries and attach importance to scientific and technological innovation;third,to implement the strategy of revitalizing rural areas and promote urban-rural integration development;fourth,to promote consumption upgrading and take full advantage of the strong driving force of the consumer market;fifth,improve the mechanism of factors flow and establish a regional coordination mechanism.