Research On The Identification And Dynamic Evolution Of The Spatial Center Structure Of Urban Agglomeration In China

There are unbalanced and uncoordinated regional development problems in China’s urban agglomerations.There are significant differences in spatial structure characteristics,spatial external forms and development stages of different urban agglomerations.With the acceleration of urbanization,higher requirements are put forward for the construction and spatial layout of urban agglomerations in China.Therefore,accurately and objectively identifying the present situation of spatial structure of urban agglomerations and understanding the evolution path of spatial structure followed by urban agglomerations in the process of formation and development will help to rationally adjust the development layout of urban agglomerations and provide theoretical and practical guidance for promoting the optimization of spatial structure of urban agglomerations.Based on the dialogue between urban agglomeration spatial layout theory and regional spatial structure evolution theory,the virtual point of urban agglomeration spatial gravity center is introduced into the spatial entity unit of urban agglomeration,and the evolution path of regional spatial structure followed by urban agglomeration in the process of formation and development is deeply explored from the perspective of gravity center,and the new concept of urban agglomeration spatial gravity center structure is put forward for the first time,and the urban agglomeration spatial gravity center structure is classified according to the division basis.A complete analytical framework is established to comprehensively study the identification,change,deviation,evolution trend and driving force of the spatial gravity center of 19 urban agglomerations in China,aiming at strengthening the understanding of the spatial pattern of urban agglomerations in China and revealing the detailed characteristics of urban agglomerations in the process of spatial structure evolution.The results show that:(1)The spatial gravity center structure of urban agglomeration can be roughly divided into three types: single-core-gravity center overlapping type,single-core-gravity center dislocation type and multi-core-gravity center dislocation type.(2)The built-up areas of China’s urban agglomerations are always expanding steadily,but the expansion speed is declining.(3)During the development of urban agglomerations,the spatial center of gravity of urban agglomerations changed from single core-center of gravity superposition to single core-center of gravity dislocation,and then to multi-core-center of gravity dislocation.(4)Raction is the first factor that affects the spatial center of gravity deviation of urban agglomerations,while endogenous force has the weakest influence.For different types of urban agglomerations,administrative force and market force have their own strengths and weaknesses.