Abstract
Air pollution seriously affects human health. The traffic and production restriction is widely used for controlling heavy air pollution. However, the effectiveness of these two policies has not been scientifically verified through a city-level study. COVID-19 pandemic caused lockdowns in many cities, which makes it possible to verify the effectiveness of these two policies. Taken Wuhan as the study area, this study firstly verifies the existence of lockdown effect on air pollution and analyzes the evolution rule of six air pollutants (PM2.5, PM10, NO2, SO2, CO and O3) using statistical methods. Then the structural break points in six air pollutants are detected with the regression discontinuity design model. Because Spring Festival overlapping COVID-19 may also affect the air pollution, in order to avoid the disturbance of Spring Festival on the results, the Spring Festival effect is also validated. The results illustrate that the effects of traffic and production restriction on six air pollutants are obviously different, in which the concentrations of PM2.5, PM10 and NO2 decrease significantly, while traffic and production restriction has no apparent effects on SO2, CO and O3. Moreover, the structural break points are verified in the four air pollutants (PM2.5, PM10, NO2 and CO), and the structural break points are caused by lockdown instead of Spring Festival. This study revealed how the traffic and production restriction affected the air pollution at a city level, and provided strong implementation basis to the air pollution control policy.
Spatial Heterogeneity Influences of Environmental Control and Informal Regulation on Air Pollutant Emissions in China