| In the contemporary era that emphasizes the concept of green development,improving the level of green total factor productivity is an inevitable choice for economic development.Therefore,in the context of vigorously promoting regional integration in the Yangtze River Delta region,it is necessary to quantify the impact of regional integration in the Yangtze River Delta region on green total factor productivity and then find realistic and feasible ways to further improve green total factor productivity in the region.Based on this,thesis considers the expansion of the Yangtze River Delta as a quasi-natural experiment to empirically test the green development effects of regional integration in the Yangtze River Delta region.The SBM model and Malmquist-Luenberger index method are first applied to measure the green total factor productivity of cities in the Yangtze River Delta region from 2005 to 2019,and relevant descriptive analyses are conducted.On the basis of measuring the green total factor productivity of urban clusters in the Yangtze River Delta region,thesis constructs quasi-natural experiments using 30 regionally integrated cities in the Yangtze River Delta region during 2005-2019,empirically analyzes the impact of regional integration on green total factor productivity using the DID model,and performs robustness using placebo test,counterfactual test,PSMDID method and removal of extreme values method test;finally,the heterogeneity of the in situ and new entrant cities is analyzed according to the different time of joining the YRD city economic coordination council.The results show that(1)the green total factor productivity of the urban agglomerations in the Yangtze River Delta region shows stage characteristics,and the green total factor productivity of the urban agglomerations in the Yangtze River Delta region has a significant upward trend during the study period,but the increase is not large and fluctuates;(2)the empirical analysis of the DID model finds that the regional integration in the Yangtze River Delta region significantly promotes the green total factor productivity,and the lag of its promotion effect(2)The empirical analysis of the DID model found that regional integration in the Yangtze River Delta region significantly promotes green total factor productivity,and the lag of its promotion effect coexists with continuity.Rationalization of industrial structure,marketization process,human capital and green total factor productivity show a positive relationship;R&D investment and government support are not significant;while foreign investment and urbanization degree have a significant negative impact on green total factor productivity;(3)green total factor productivity of in-situ cities is more affected by regional integration than new cities.Based on the above analysis,in order to improve the green total factor productivity of the urban agglomerations in the Yangtze River Delta region and promote the regional economic development of the Yangtze River Delta region,it is necessary to break through the administrative boundaries within the region,actively promote regional cooperation and reasonably plan the regional industrial division of labour;at the same time,in the process of vigorously promoting the regional integration of the Yangtze River Delta region,it is also necessary to bear in mind the ecological aspects of regional integration. |
