环境政策对城市生态效率的影响与机制研究 —— 基于生态文明先行示范区的准自然实验.

Based on the panel data of 204 prefecture-level cities in China from 2004 to 2019, this paper used the double-difference method to study the impact of ecological civilization demonstration area policy on ecological efficiency with the help of“quasi-natural natural experiment”from ecological civilization demonstration area. Results showed as follow.（1）Overall, the implementation of ecological civilization demonstration area policy has significantly promoted the improvement of ecological efficiency. At the same time, various robustness tests such as excluding the influence of other policies, counterfactual testing, replacing sample data, and propensity score matching-based difference-in-difference（PSM-DID）were carried out to ensure the reliability of the results.（2）Heterogeneity analysis showed that ecological civilization demonstration area policy had a more significantly effect on the improvement of ecological efficiency in the large cities and cities in eastern and central regions.（3）Mechanism analysis showed that ecological civilization demonstration area policy can improve the ecological efficiency of cities by driving technological innovation and optimizing industrial structure. Accordingly, it is proposed to further summarize the effective practices of the ecological civilization demonstration area policy. And a combination of policies should be carried out based on the consideration of heterogeneity factors. In addition, it is also necessary to focus on transforming and upgrading advantageous industries and stimulating innovation capabilities. [ABSTRACT FROM AUTHOR]