中央环保督察对城市空气质量改善的政策效用评估——基于DID双重差分法分析

Evaluation of the policy effectiveness of the impact of central environmental supervision on urban environmental quality in China——Analysis based on difference-in-differences method

使用2012-2022年中国220个地级市的PM2.5、PM10、NO_(2)、SO_(2),的年均浓度值作为被解释变量,以是否为污染防治重点城市划分试验组与对照组,利用双重差分法检验中央环保督察对城市空气质量的影响,并通过倾向得分匹配检验分析结果的稳定性。研究发现:中央环保督察可以显著降低污染防治重点城市的PM10、SO_(2)和PM2.5的年均排放浓度,减少各项污染物排放量,改善城市空气质量。建议因地制宜开展环境治理工作,同时根据每个城市的实际情况确定督察工作的重点,对不同地区确定不同的空气环境治理目标。

The article uses the annual average concentration values of PM2.5,PM10,NO_(2),and SO_(2) in 220 prefecture-level cities in China from 2012 to 2022 as the explanatory variables.Based on whetherit is a key city for pollution prevention and control,the article uses the difference-in-differences method to innovate its research perspective and test the impact of central environmental supervision on urban environmental quality.Research has found that central environmental inspectors can significantly reduce the annual emission concentrations of PM10,SO_(2)and PM2.5 in key pollution prevention and control cities,reduce the emissions of various pollutants,and improve urban air quality.It is recommended to carry out environmental governance work according to local conditions,while determining the focus of supervision work based on the actual situation of each city,and determining different air environment governance goals for different region.