Does regional planning policy of Yangtze River Delta improve green technology innovation? Evidence from a quasi-natural experiment in China

Green technology innovation is an important way to solve the dilemma of economic growth and environmental protection, while the relevant policies issued by the government have an important impact on the promotion of regional green technology innovation. This paper regards the implementation of the Regional Planning of Yangtze River Delta (RPYRD) as a quasi-natural experiment, using the panel data of 274 cities in China from 2003 to 2016 to explore the green technology innovation effect of regional planning and its transmission mechanisms through the double-fixed effect model and the difference-in-difference (DID) method. The results show that (1) the implementation of the RPYRD promotes regional green technology innovation significantly and the green technology innovation effect of the policy is increasing year by year. (2) There is significant regional heterogeneity in the incentive effect of green technology innovation in regional planning. The policy effect is more obvious in cities with a larger scale, a higher level of human capital and less resource dependence. (3) The regional planning promotes green technological innovation by optimizing industrial structure, reducing FDI and increasing R&D investment.