School of Management, Tianjin University of Technology, Tianjin 300384, China.
Int J Environ Res Public Health. 2022 Oct 20;19(20):13623. doi: 10.3390/ijerph192013623.
The environmental effects of national new areas have been an important topic but received little attention in academia. This study conducts a quasi-natural experiment using panel data of China's 282 prefecture-level cities from 2006 to 2019, and evaluates the establishment of national new areas on urban ecological efficiency using the staggered difference-in-difference (DID) method, tests the robustness, and further examines the influential mechanism and urban heterogeneity of the empirical results. The results show that the establishment of national new areas has significantly improved urban eco-efficiency. Moreover, the mechanism analysis of the influences shows that national new areas improve urban eco-efficiency by improving urbanization level and urban transportation infrastructure. In addition, the heterogeneity analysis of cities shows that national new areas of cities in eastern and central regions are both significantly improving urban eco-efficiency, while those in western and northeastern regions are not. Furthermore, the promotion effect in the regions of "one new area in one city" model is better than that in "one new area in two cities" model; national new areas in non-resource-based cities show more positive effects on promoting urban eco-efficiency than those in resource-based cities. The conclusions reliably evaluate the results of the current construction of national new areas and provide feasible suggestions for further implementation of the related policy to balance economic development and environmental protection.
国家新区的环境效应一直是一个重要的课题，但在学术界却很少受到关注。本研究利用中国 2006 年至 2019 年的 282 个地级市的面板数据进行了一项准自然实验，采用双重差分（DID）方法评估了国家新区的建立对城市生态效率的影响，检验了实证结果的稳健性，并进一步考察了影响的作用机制和城市异质性。结果表明，国家新区的建立显著提高了城市生态效率。此外，影响的机制分析表明，国家新区通过提高城市化水平和城市交通基础设施来提高城市生态效率。此外，城市的异质性分析表明，东部和中部地区的国家新区都显著提高了城市生态效率，而西部地区和东北地区的国家新区则没有。此外，"一个城市一个新区"模式的促进效果要好于"两个城市一个新区"模式；非资源型城市的国家新区对促进城市生态效率的积极作用大于资源型城市的国家新区。这些结论可靠地评估了当前国家新区建设的结果，并为进一步实施相关政策以平衡经济发展和环境保护提供了可行的建议。
