An Analysis On The Evolution Of Hierarchical System In The Yangtze River Delta Urban Agglomeration

Due to the ability to integrate resources,Urban agglomeration,as the advanced stage of urban development,its development level affects the process of urbanization in China.The urban agglomeration has been put forward as the main part of the new urbanization form during the process of the implementation of new urbanization strategy.In the context of the “new normal” economy,how to improve the level and quality of China's economic development,the development of urban agglomeration made a severe test.The urban agglomeration is within a certain geographical area,with a large or mega-city as a core,consisting of at least three metropolitan areas(districts)or large cities as the basic constituent units.Under the action of the market mechanism,the exchange of economic factors such as labor force,capital and technology within the urban agglomeration area makes the comparative advantage among the cities,and plays an important role in the hierarchical system and social development of the urban agglomeration.The ideal urban agglomeration is a city community with functional complementation and good coordination mechanism in the aspects of population,economy,society,culture and overall structure.It has a function complementation and good coordination mechanism in space boundary,resource allocation,industrial division of labor and humanistic communication.The urbanization level is an important content of urban agglomeration construction,and it is also one of the long-term studies of geography and regional economics.Therefore,based on the analysis of the theory and related literatures of the urban agglomeration system,this paper analyzes the formation and dynamic mechanism of the urban agglomeration system.On this basis,it analyzes the hierarchical system,the rationality and problems of the urban agglomeration of the Yangtze River Delta,and then put forward the suggestions for optimizing the urban agglomeration system.First of all,this paper explores the possible laws of the evolution of urban agglomeration from the research literature of regional economics,new economic geography and urban economics,and then combs the literature of the urban agglomeration system at home and abroad in recent years: It is found that different subjects emphasize different aspects of the urban agglomeration system.Geography mainly regards the spatial structure as the research subject,ignoring the functionalresearch;the economics focuses on the urban agglomeration from the aspects of industrial agglomeration,diffusion and factor flow structure.The hierarchical system of urban agglomeration contains three dimensions: scale structure,functional structure and spatial structure,while the relevant literature only choose one of them,it can't fully realize the problem of urban agglomeration system,and most of them use static analysis,lack of time dimension comparation.In the course of the research about urban agglomeration of the Yangtze River Delta,the regional planning of a certain year is not the same as the regional planning of the whole study period,and the influence of the government planning on the urban agglomeration system can't be analyzed.This paper will analyze the hierarchical system of the Yangtze River Delta urban agglomeration from the three aspects of scale structure,function structure and spatial structure,and incorporate the time dimension,and analyze the hierarchical evolution characteristics of urban agglomeration according to the perspective of evolution.Secondly,this paper analyzes the scale structure of the Yangtze River Delta urban agglomeration from the perspective of population and economy.In the past,the study of population perspective choose urban and municipal area household population,while this article selects urban resident population,more proper for the characteristics of urban agglomeration scale structure.In the aspect of research method,we choose the order-scale rule to study the evolution of the scale structure of the Yangtze River Delta urban agglomeration,and select the Rank-Clock to study the order change and evolution characteristics of individual cities in the Yangtze River Delta urban agglomeration.This paper chooses mining functions,industrial functions,construction functions,traffic and communication functions,commercial functions,financial functions,real estate functions,scientific research management functions,administrative functions,social service functions,and other services as the study subject,not only analyzes the basic functions and non-basic functions of the Yangtze River Delta urban agglomeration from Location Quotient,but also analyzes the functional scale and functional intensity of the Yangtze River Delta urban agglomeration and the city 's leading departments,so that we could get the evolution characteristics of the functional structure of the Yangtze River Delta urban agglomeration.Based on the analysis of the spatial structure of the urban agglomeration in the Yangtze River Delta,this paper chooses 23 indicators,such as economic development,social development,investment environment,science and technology informatization and infrastructure,in order to construct the urban comprehensive strength evaluation index system.Factor analysis was used to analyze the spatial strength of the Yangtze River Delta urban agglomeration,and the spatialstructure of the Yangtze River Delta urban agglomeration was obtained by using ARCGIS10.2.At the same time,we use the Getis-Ord G * index to study the Yangtze River Delta The Evolution of Spatial Correlative Patterns of Comprehensive Development Level of Urban Agglomeration.Finally,based on the analysis of the hierarchical evolution characteristics of the Yangtze River Delta urban agglomeration from three aspects: scale,function and structure,this paper summarizes the conclusion of the study about the stratification of the Yangtze River Delta urban agglomeration.On this basis,This paper puts forward some suggestions on how to develop the reasonable system of the Yangtze River Delta urban agglomeration with high level and quality development potential.At the same time,the article finally summarizes the shortcomings of the whole research process and explains the direction of further improvement.