创新型城市试点改善了城市环境吗?

Has the innovative cities pilot project improved the urban environment?

创新驱动发展为环境污染治理提供了新的动力和方向,创新型城市试点是创新改善环境的典型空间例证。基于中国2003—2015年282个城市面板数据,运用双重差分法评估了创新型城市试点对城市环境的改善效应。结果表明:创新型城市试点能显著减少以PM2.5、工业二氧化硫、工业废水为代表的污染物排放,从而改善城市环境。与此同时,中介效应机制的检验结果发现,创新能力提升与产业结构优化升级是其中主要的影响渠道,但政府环境干预的机制暂未达到理想的环境改善效果。进一步的拓展分析发现:创新型城市试点对经济欠发达地区具有"雪中送炭"效应,对经济发达地区也具有"锦上添花"作用,且对发达地区的环境改善程度更为显著;政策所产生的空间溢出效应已在流域治理中显示出良好效果,但空气治理中的区域联动仍需加强。坚持市场在绿色资源空间配置中的决定性地位,更好地发挥政府在治理污染中的作用,以及全面提升区域协同治理效能,是创新型城市试点发挥更大环境改善效应的关键所在。

Innovation-driven development provides new impetus and direction for environmental pollution control.Innovative city pilot is a typical spatial example of that.Based on the panel data of 282 cities in China from 2003 to 2015,this paper uses the difference-in-differences method to evaluate the improvement effect of innovative city pilot on the urban environment.The results show that innovative city pilot can significantly reduce representative pollutant emissions such as PM2.5,industrial sulfur dioxide and industrial wastewater,thereby improving the urban environment.At the same time,the test result of the intermediary effect mechanism shows that the improvement of innovation capability and the optimization and upgrading of industrial structure are the main means of influence,but the mechanism of government environmental intervention has not yet achieved the desired effect of environmental improvement.Further expansion analysis finds that the innovative city pilot has the effect of"sending charcoal in the snow"to underdeveloped regions and the effect of"icing on the cake"to developed regions,and the effect of environmental improvement in developed regions is more significant.Moreover,the spatial spillover effect produced by the policy has shown good results in watershed governance,but the regional linkage in air governance still needs to be strengthened.Therefore,insisting on the decisive role of the market in the spatial allocation of green resources,giving better play to the government’s role in pollution control,and comprehensively improving the effectiveness of regional coordinated governance are the keys for innovative city pilot project to exert greater environmental improvement effects.