Threshold And Spatial Spillover Effects Of Urbanization On Regional Eco-efficiency In The Middle Reaches Of The Yangtze River

In the past decade,the urbanization rate of China’s permanent population has been rising with an average annual growth rate of 1.39%.In 2021,the urbanization level of China’s permanent population has reached 64.72%,indicating that China’s urbanization progress has made remarkable achievements.The rapid development of urbanization and the continuous expansion of urban scale promote the rapid growth of China’s economy.At the same time,rapid urbanization has a certain impact on the ecological environment.Such as ecological degradation,environmental pollution,climate warming.Under these severe circumstances,we must uphold the concept of ecological progress and pursue green development.Urban agglomeration in the middle reaches of the Yangtze River is regarded as the demonstration area of China’s mega urban agglomeration and an important strategic implementation area.With significant ecological advantages,it has always adhered to green development and coordinated development as the main goal.In this context,grasp the characteristics of urban agglomeration development stage of urbanization in the middle reach of Yangtze river,deeper understanding in the progress of urbanization on the regional ecological efficiency and the effect of exploration,the nonlinear influence relation between for further realizing high quality of urbanization development,improve the efficiency of regional ecological,strengthen regional coordination management has important significance.In this thesis,the threshold and spatial spillover effects of urbanization on regional ecological efficiency were studied in 37 urban agglomerations in the middle reaches of the Yangtze River.Panel data from 2004 to 2018 were taken as samples to explore the impact of urbanization on regional ecological efficiency.First of all,the urbanization level of population in prefecture-level cities is counted,and the regional ecological efficiency is calculated through the super-efficiency DEA model.On the basis of the two,relevant theoretical assumptions are proposed.With the help of the panel threshold model,the urbanization level is taken as the threshold variable,and the tertiary industry structure,urban employment number,per capita GDP,and energy consumption per 10,000 YUAN OF GDP are added as control variables to verify the threshold effect of urbanization on regional ecological efficiency.Finally,the spatial spillover effect of urbanization on regional ecological efficiency is proved by spatial econometric model on the basis of nonlinear influence.Research shows that:（1）Urbanization and regional ecological efficiency of urban agglomerations in the middle reaches of the Yangtze River showed an overall rising feature during the study period.The urbanization level of the three provincial capitals all exceeded 70%,and the overall regional ecological efficiency increased significantly after 2012.（2）Empirical analysis proves that urbanization has a nonlinear impact on regional ecological efficiency,and the threshold value is 71.6%.The influence of threshold value on regional ecological efficiency is positive before and after the threshold value,and the positive influence deepens after crossing the threshold value,and the influence coefficient increases from 2.67 to 3.21.The emergence of the threshold indicates that the development of urbanization has entered a new stage.（3）Among the spatial spillover effects,urbanization and technological level have strong spatial spillover effects on regional ecological efficiency.The total effect of urbanization is 1.44,the direct effect is 1.89,and the indirect effect is-0.43,which has a negative spillover effect on the surrounding areas.Total effect,direct effect and indirect effect were 0.44,0.40 and 0.04 respectively.The improvement of technological level is mainly reflected in the improvement of regional ecological efficiency.Based on the above research conclusion,during the process of urbanization,this article on how to improve the efficiency of regional ecological put forward the following Suggestions: first,actively promote the high quality of urbanization development,advocate green production way,energy-saving technology innovation,and raise the proportion of the tertiary industry,etc.,to reduce the negative externality of influence in the process of urbanization.Second,differentiated strategies for improving regional ecological efficiency should be implemented according to the threshold value.For regions that do not cross the threshold value,the main focus should be on urbanization development,and policies such as household registration system reform and talent introduction should be adopted to continuously promote population transfer to urban areas and accelerate urbanization construction.For areas that have already crossed the threshold,the main goal should be to improve living standards and change production modes,actively advocate green lifestyles,strengthen research and development and promotion of environmental protection technologies,and achieve coordinated development of urbanization and environmental governance.Third,strengthen trans-regional cooperation in ecological protection,jointly establish ecological environment monitoring and protection organizations,jointly control environmental pollution through data sharing,and optimize the spatial layout of polluting enterprises.In order to reduce the negative impact of environmental pollution on the surrounding areas in the process of urbanization.