开发区影响城市的绿色经济增长吗? ——基于285个城市的准自然实验

Whether Development Zones Can Affect the Green Economic Growth of Cities:A Quasi-natural Experiment Based on 285 Cities

基于包含非期望产出的超效率SBM模型和GML指数,测算2004—2018年285个城市绿色全要素生产率(GTFP)的增长率及分解指标,运用Tobit-DID模型和面板门限模型评估国家级开发区设立对城市GTFP增长的影响和作用机制。结果表明:开发区设立能够显著提升城市的全要素生产率(TFP)增长水平,但考虑资源消耗和污染排放后,与城市GTFP增长率呈现显著负向关系,该结果通过了一系列稳健性检验。开发区的污染企业数量和规模上升加剧了城市的污染排放,是制约城市GTFP增长提升的主要因素。受持续时间和核准面积的影响,开发区企业规模增长对城市环境污染具有门限效应。持续时间越长、核准面积越大,区内企业规模增长对城市环境污染的影响系数越大。因此,应适当提高开发区环境入园门槛,建立污染企业淘汰机制,加快推进开发区绿色改造,以促进城市绿色经济增长。

Based on the super-efficient SBM model and GML index including unexpected output,this paper calculates the growth rate and decomposition index of green total factor productivity(GTFP)of 285 cities from 2004 to 2018,and uses Tobit-DID model and panel threshold model to evaluate the influence and mechanism of the establishment of national development zones on the growth of urban GTFP.The results show that the establishment of the development zones can significantly improve the total factor productivity(TFP)growth level of the city,but it has a significant negative relationship with the GTFP growth rate of the city after considering resource consumption and pollution emissions.After passing a series of robustness tests,the result still holds.The increase in the number and scale of polluting enterprises in the development zones intensifies the pollution discharge of the city and is the main factor restricting the growth and promotion of the city GTFP.Affected by the duration and approved area,the growth of enterprise scale in the development zones has a threshold effect on urban environmental pollution.The longer the duration is and the larger the approved area is,the greater the impact coefficient of enterprise scale growth on urban environmental pollution is.Therefore,we should appropriately raise the threshold for the environment of the development zones to enter the park,establish the elimination mechanism of polluting enterprises,and speed up the green transformation of the development zones so as to promote the growth of urban green economy.