Study On The Spatiotemporal Evolution Of Carbon Productivity And Its Influencing Factors In The Yangtze River Delta Urban Agglomeratio

Carbon productivity reflects the economic output per unit of carbon dioxide emission and is the core index to measure the development level of low-carbon economy.As an important pole of China’s economic growth,the Yangtze River Delta urban agglomeration is the spatial carrier and strategic support of China’s regional economic development strategy and has a certain radiation effect on the Yangtze River Economic Belt and even the whole country.However,the urban agglomeration is also one of the main sources of carbon emissions in China.Therefore,the carbon productivity of the Yangtze River Delta urban agglomerations and its changing trend determine whether our country can achieve the "double carbon" goal on the premise of steady economic growth to a certain extent.Based on the calculation of the carbon productivity of the Yangtze River Delta urban agglomeration from 2004 to 2018,this study used the Moreland index to test the spatial correlation of the carbon productivity of the urban agglomeration,accurately described the agglomeration type of carbon productivity of the urban agglomeration through the cold-hot analysis and demonstrated the spatial structure and agglomeration characteristics of the carbon productivity of the urban agglomeration.Dagum Gini coefficient was used to explore the regional differences of carbon productivity in urban agglomerations,and a spatial econometric model was built to investigate the influencing factors of carbon productivity in urban agglomerations,and to test the spatial spillover effects of influencing factors of carbon productivity.It provides differentiated,quantified and scientific information for urban agglomeration to formulate emission reduction policies,and the results are helpful to formulate regional development policies according to local conditions and promote regional low-carbon economic development.The main conclusions of this study are as follows:(1)On the whole,the average carbon productivity of urban agglomerations increased by 515,000 yuan/ton from 2004 to 2018,and all cities maintained a growth.In addition,taking 2013 as the boundary,the carbon productivity of all cities maintained a slow growth at a low level before 2013,and the growth rate increased rapidly after 2013.Wuxi and Suqian were the cities with the highest and lowest carbon productivity in 2018,while Shanghai and Yancheng were the cities with the highest and lowest carbon productivity growth from 2004 to 2018.(2)Carbon productivity in urban agglomerations has significant positive spatial correlation and spatial agglomeration,and the two characteristics are highly stable and path dependent.The main spatial differences of carbon productivity mainly come from the differences between administrative divisions.The differences between cities under different provincial administrative divisions are much larger than the differences between cities under the same provincial administrative divisions.(3)A variety of influencing factors have a significant impact on the carbon productivity of the Yangtze River Delta urban agglomeration,and there is an obvious spatial spillover effect.Economic development level and environmental regulation not only significantly promote the growth of local carbon productivity,but also have a significant positive spatial spillover effect.On the contrary,industrial structure factors inhibited the improvement of local carbon productivity and produced significant negative spatial spillover effect.