The spatio-temporal evolution characteristics and influencing factors of collaborative governance of air pollution in the Yangtze River Delta region

In the strategic background of high quality integration in the Yangtze River Delta (YRD), it is a feasible choice to build an inter-regional environmental collaborative governance system to improve the effectiveness of air pollution control in the region. This paper constructed an evaluation system of coupling degree of air pollution regulation from three dimensions: policy documents, implementation process and governance effect of environmental regulation, and then explored the spatio-temporal evolution characteristics of coupling degree of air pollution regulation in 41 cities in the YRD from 2003 to 2019. On this basis, the cities in the YRD are divided into regional collaborative governance groups, and the synergy degree of air pollution control is measured respectively, thus the influencing factors of collaborative governance of air pollution in the YRD are explored. The results show that: (1) The coupling degree of air pollution regulation in all the cities shows the characteristics of agglomeration development, with Shanghai being the highest, followed by Zhejiang province and Jiangsu province, and Anhui province being the lowest, while the regional differences are narrowing. (2) The synergy degree of air pollution control in the YRD as a whole was low and showed a slow rising trend in the fluctuation, but the synergy degree of air pollution control remained at a high level after the division of regional collaborative governance groups. (3) The results of influencing factors analysis show that the differences in opening up, public transportation and greening construction between regions have significantly inhibitive effect on the collaborative governance of air pollution in the YRD, while the differences in economic growth and technological innovation have significantly positive effect.