中央环保督察与地方大气质量改善——基于多期双重差分法的检验

 采用2014-2018年中国225个地级市的面板数据，以各地市当年PM_2.5、PM₁₀、NO₂、SO₂、CO、O₃的年均浓度作为被解释变量，通过多期双重差分的方法检验了中央环保督察制度在改善地方大气质量方面的政策效果及其持续性。研究发现：中央环保督察对PM₁₀、SO₂和CO的浓度改善具有显著作用；在政策效果持续性上，相比PM₁₀，中央环保督察对地方SO₂、CO浓度的改善更具有持续性。建议进一步常态化中央环保督察制度以持续推动地方大气环境质量改善，关注移动源、建设工程扬尘与二次污染物防治以推动多类大气污染物的减排，实现空气质量的综合提升。

Central inspection of ecological and environmental protection and the improvement of local air quality: Evidence from using multiphase difference-in-difference method

As an important measure to strengthen the local government's enforcement in the environmental protection and to promote the national sustainable air pollution control, using the panel data of 225 prefecture-level cities in China from 2014 to 2018, this paper analyzes the policy effect of the central environmental protection inspection on the local air quality improvements by applying the multi-phase difference-in-differences method. It is shown that the central inspection of the ecological and environmental protection has a significant effect on the reduction of PM10, SO₂, and CO; a continuous effect on the reduction of the local SO₂ and CO; while it does not work well for the sustainable reduction of PM10. For the improvement of the local air quality, we suggest to further implement the Central Inspection of Ecological and Environmental Protection, and to pay more attention to the control of the mobile sources pollution, the construction dust, and the secondary air pollutants.