The Spatial Pattern And Evolution Trends Simulation Of Shrinking Cities In China

China’s regional development has become unbalanced with the disappearance of the demographic dividend and the transformation of economic structure in the process of rapid and large-scale urbanization of population and land.The phenomenon of urban shrinkage characterized by population decline,economic recession,and declining space quality began to appear in this context,even in regions with a high strategic position like the Yangtze River Economic Belt(YREB).Urban shrinkage has caused a series of challenges in the process of new-type urbanization.Therefore,academia and urban planning fields need to promote localized urban shrinkage research in China.Based on the research ideas of pattern process-mechanism revealing-trend simulation,this study takes the YREB as an example.Firstly,the degree of urban shrinkage,shrinkage dimensions and shrinkage trajectory of the counties in 2000-2005,2005-2010 and 2010-2015 are identified under the three scales of global,watershed and urban agglomeration based on the the population,economy and space urban shrinkage index.Secondly,the scale difference and spatial agglomeration characteristics of multi-dimensional shrinking cities at different scales are measured based on the Theil coefficient and spatial autocorrelation model.Thirdly,from the perspectives of population agglomeration,economic agglomeration,and public service agglomeration,the influencing factors of multi-dimensional shrinking cities are quantified using the spatial measurement model.Finally,the shrinking cities of economic dimensions in the YREB in the two periods of 2020-2025 and 2025-2030 have been visualized using GM(1,1)to enrich the case studies of shrinking cities in China.The main research conclusions are as follows:(1)There were 387,328,and 217 shrinking cities in the population dimension in the three periods of 2000-2005,2005-2010,and 2010-2015,accounting for 47.60%,40.34%,and 26.69% of the total counties in the YREB.The degree of shrinkage in the three periods is dominated by slight contraction,which is mainly distributed in the upper and middle reaches of the Yangtze River.There were 202 and 199 shrinking cities in economy dimension and space dimension in each period,and the degree of shrinkage was mainly light shrinkage and moderate shrinkage.In terms of shrinkage dimensions,the shrinking cities in the three periods have been dominated by the one-dimensional shrinking population shrinkage type.The shrinking trajectory of multi-dimensional shrinking cities is dominated by temporary shrinkage,and the longer the shrinking trajectory,the smaller the number of corresponding shrinking cities.(2)There are certain differences in the shrinkage degree,shrinkage dimension and shrinkage trajectory of shrinking cities in the three periods of 2000-2005,2005-2010 and 2010-2015 at the basin scale and the urban agglomeration scale.The degree of shrinkage is mainly small and light shrinkage in different areas.The shrinkage dimension is mainly one-dimensional shrinking population shrinking in different areas,and the number of three-dimensional shrinking cities is the least.In terms of shrinking trajectories,the number of multi-dimensional shrinking trajectories identified in the upper reaches of the Yangtze River and urban agglomeration in the Middle Reaches of the Yangtze River is the largest,indicating that the development of cities in these two regions fluctuates greatly.(3)The distribution of multi-dimensional shrinking cities has a significant spatial effect in the YREB.For population shrinking cities and economy shrinking cities,the scale difference of shrinking degree has become smaller,while the scale difference of the spatial dimension has shown an increasing trend based on the measurement result of Theil coefficient.The agglomeration patterns of multi-dimensional shrinking cities in the west,central and east of the YREB are quite different,forming a spatial pattern in which urban growth and local shrinkage coexist in the YREB reflected by the results of Moran’I measurement.(5)In 2020-2025 and 2025-2030,there are 158 economical shrinking cities in the YREB and they will mainly be slight,mild and moderate shrinkage,while the severely shrinking cities are mainly concentrated in Zhejiang Province,which shows that the economic development of Zhejiang Province should be paid more attention to.(6)The population,economy,and public service agglomeration of the multi-dimensional shrinking city has significant spatial dependence on space.Factors such as fixed asset investment,total social consumption,industrial output value,and built-up area have significant impacts on urban population gathering,economic gathering and public service gathering.Among them,the built-up area has significant negative direct effects and spatial spillover effects,indicating that the expansion of built-up area is not beneficial to the governance of shrinking cities.