Evaluation And Convergence Mechanism Of Green Total Factor Productivity Of Urban Agglomerations In The Middle Of The Yangtze River

With the more comprehensive reform and opening up,our economy has changed from the high speed time to the high quality development time.How to improve the progress quality of our motherland’s economy and search a good point between the ecological environment and economic progress are major issues for our motherland at this time.The improvement of GTFP is an important indicator of high quality regional development,and urban agglomerations play a leading and important role in the high quality development for our country’s regional economy.As one of the national-level urban agglomerations,the 31 cities in the middle Yangtze River go through the east to the west of our country and it connects the north to the south.The quality of its green development can affect the environmental friendly and high quality progress of all the Yangtze River Economic Belt and deciding the middle rise strategy.This study utilizes the 31 cities in the middle of the Yangtze River as the research target.First,the Super-SBM model containing unexpected output and using the GML index to measure the GTFP and its decomposition of the 31 cities in the middle of the Yangtze River from 2008 to 2019.Then,Using Moran’s I index to calculate the autocorrelation in spatial of GTFP in the 31 cities of the middle Yangtze River.Furthermore,the standard deviation ellipse is used to analyze the difference in time and space evolution and the migration trajectory of the center of gravity,and finally the GTFP index is converged sexuality test and influence mechanism analysis.The research found that:(1)From 2008 to 2019,the GTFP of 31 cities in the middle of the Yangtze River results a total growth trend,and it’s an average growth rate of 5.07% every year.The big numbers of the GML index were located in Wuhan,Changsha,Nanchang and other cities;In the three sub-urban agglomerations,the GTFP of cities in the Wuhan urban circle is highest,and the second is the cities around Changsha,Zhuzhou and Tan,and the 10 cities in Poyang Lake with a poor economic foundation in the three sub-urban agglomerations is also lower in green total factor productivity;(2)From 2008 to 2019,The GTFP of 31 Cities in the middle of the Yangtze River has a self-evident spatial correlation,and has obvious spatial spillover effect;(3)The distribution characteristics of the standard deviation ellipse are highly correlated with the shape of the urban agglomeration,the differences in the economic strength of each city,and the total population of different cities.The long axis is from northwest to southeast.The migration centers are all distributed in Xianning City,Hubei Province,and the overall migration range is not large,generally showing first to the northwest and then to the south.(4)The GTFP of the 31 cities in the middle of the Yangtze River has a sigema convergence trend from 2013 to 2019,and the GML index difference between cities gradually increased during this period.The GTFP of the 31 cities in the middle of the Yangtze River and the three sub-urban agglomerations from 2008 to 2019 have passed the absolute beta convergence and conditional bate convergence tests,indicating that there is a catch-up effect among cities and a development trend toward their own steady state;The spatial convergence test display that the GTFP of the 31 cities in the middle of the Yangtze River has an obvious spatial spillover effect,and adding spatial factors can accelerate the convergence speed obviously of the 31 cities in the middle of the Yangtze River.The control variables of the level of opening to the outside world and the intensity of R&D investment have a significant role in promoting the convergence of GTFP in this region.