The Coupling Relationship Between Land Use And Urbanization Of The Yangtze River Delta Urban Agglomeration

The Yangtze River Delta urban agglomeration is the core strategic area of China’s social economy and urbanization development,but the conflict between humanity and land is more and more severe in the process of development.It is beneficial to the health of land-use system and to realize the sustainable development of cities to carry out the research on the coupling relationship between land use and urbanization.This paper constructes super-efficient SBM model and comprehensive evaluation model with the data of land use and social economic for 2002-2017 to measure the development level of land use efficiency and urbanization and analyzes space-time features.Reveale the coupling mechanism between land use and urbanization from the aspects of behavior process and feedback process through PVAR model.And the static coupling relationship is evaluated by coupling coordination model to determine the coupling coordination stage of 26 cities.Then summarize the development law and typical types and put forward the optimization suggestions.The results are as follows.(1)The land use efficiency of the Yangtze River Delta urban agglomeration slowly increases in fluctuations experienced three historical stages of the downward period of 2002-2005,the rising period of 2005-2014 and the high-quality rising period in 2014-2017.The level of urbanization development is most affected by spatial urbanization,but is currently driven by industrial urbanization.Its average annual growth rate is as high as 5.66% and the growth rate slows down after 2011.The differences in the province are more significant than the inter-provincial differences,both of which are shrinking.In the spatial distribution,the high-value areas distributes along the traffic line of Shanghai-Nanjing,Shanghai-Hangzhou and Hangzhou-Ningbo,forming a "Z"-type development axis,while extending from Nanjing to Hefei.(2)The coupling mechanism between land use and urbanization includes "promote and coerce" and "support and restraint".Empirical results show that industrial urbanization has a coercive effect on the land-use efficiency considering non-expected output.Spatial urbanization can promote it positively.But population urbanization promotes it in the early stage,and later inhibits.The explanation degree of land use efficiency is “spatial urbanization>population urbanization>industrial urbanization”,while the influence of land use efficiency on the sub-system of urbanization is “industrial urbanization>population urbanization= spatial urbanization”.(3)2002-2017,the coupling coordination degree between land use and urbanization is constantly improving in the Yangtze River Delta city group.But it is still in the run-in stage.With 2005 as a demarcation point,the state is from basic incongruity to basic coordination,however,still far from the high level of coordination.According the evolution law,it transformes from period Ⅲ to period Ⅳ as a whole in the study period,meanwhile,Shanghai has entered period Ⅴ already.What’s more,the coupling coordination degree has the hierarchical characteristics of cascade development.The positive role of Shanghai decreases with the distance.Finally,it summarizes 8 typical types according to the development characteristics and puts forward specific targeted optimization measures.