Research On The Function Evaluation And Coupling Features Of "Production-livingecological" In Yangtze River Delta Urban Agglomeration

With the rapid advancement of my country’s industrialization and urbanization,the demand for land resources is increasing day by day.At the same time,there are also many problems that we cannot ignore,such as resource depletion,environmental pollution,spatial development disorder,spatial dysfunction and urban Sickness and other issues,this goes against the new development concept of innovation,greenness,coordination,openness,and sharing,and also restricts the sustainable development of the economy and society.At the Fifth Plenary Session of the 18 th National Congress of the Communist Party of China,it was proposed to focus on balanced and comprehensive development,promote coordinated development,and ultimately achieve overall system development.The coordinated development of the "P-L-E" of the land and space has become a requirement of national development.In this context,it is of great theoretical and practical significance to evaluate the "P-L-E" function,carry out the calculation of the degree of coupling and coordination of land and space utilization,and analyze its time and space changes.Based on relevant domestic and foreign researches,this research combines the development reality of the Yangtze River Delta urban agglomeration,takes 26 prefecture-level cities in the Yangtze River Delta urban agglomeration as the research unit,and reorganizes the "P-L-E" space theory.Reorganized the concept of the “three births” function,established an index system to evaluate the "P-L-E" function of urban agglomerations,and on this basis,introducing the coupling coordination degree model to measure and analyze the characteristics of the coupling coordination of the "P-L-E" function in the land space of the Yangtze River Delta urban agglomeration.The research shows:(1)The evaluation value of the "P-L-E" function of the cities in the Yangtze River Delta urban agglomeration tends to rise during the study period.From the spatial distribution point of view,the evaluation value of production and living functions of the eastern cities in the region is higher than that of the western part.In terms of ecological function scores,The western part is higher than the eastern part,and the functions of the "P-LE" of the cities in the region show obvious differences.The functional advantages of each city are divided into 6 categories.When improving the "P-L-E" function,it is necessary to promote the superior function while paying attention to the development of other functions to avoid the "P-LE" dysfunction.(2)Judging from the time series characteristics of the "P-L-E" functional coupling coordination degree of the Yangtze River Delta urban agglomerations,from 2009 to 2018,the coupling coordination level of the urban agglomerations showed an overall upward trend,with the coupling coordination degree value ranging from 0.498 to 0.627.The coordination type is between primary coordination and intermediate coordination.In the period from 2009 to 2015,the degree of coupling and coordination of the "P-L-E" function of the land and space has shown a slow growth.From2015 to 2018,the degree of coupling and coordination has shown a trend of slowing down.The type of coupling coordination of territorial "P-L-E" function is in the primary coordination and intermediate coordination stages as a whole.The overall coupling coordination level of urban agglomerations is not high,and there is room for improvement in coupling coordination.(3)From the perspective of the overall pattern of coupling coordination among the Yangtze River Delta urban agglomerations,most of the higher-level coordination cities are located in the eastern part of the urban agglomeration,while the cities with low coupling and coordination are concentrated in the western part of the urban agglomeration.Shanghai has a relatively high degree of economic and social development,which radiates and promotes the development of surrounding cities.By absorbing radiation,the coordination degree of cities around provincial capital cities is also rapidly improving,forming a pattern of concentrated distribution to provincial capital cities.Most of the cities with intermediate and wellcoordinated urban agglomerations are located in the eastern part of the urban agglomeration,around Shanghai and coastal areas.In 2009,2014 and 2018,the global Moran index of the coordination degree of the "P-LE" function of each city in the Yangtze River Delta urban agglomeration was positive,indicating that the coordination of the "P-L-E" function of each city is spatially positive,and the "P-L-E" of the city cluster Functional coordination has the characteristics of spatial aggregation.The analysis result of the local autocorrelation LISA diagram shows that the coordination of the functions of the "P-L-E" of the Yangtze River Delta urban agglomeration presents the characteristics of high-high and low-low bipolar clustering.(4)From the results of influencing factors,the influential factors that are strongly related to the "P-L-E" functional coupling and coordination are the state of infrastructure,the government’s ability to regulate and control,the level of economic development,the carrying capacity of resources and the environment.It is the level of social security and intellectual support.In terms of development policies,the cities should strengthen coordination,scientific management,and unified planning to promote the coordinated development of the "P-L-E" function.