Study On Evaluation Of The Effects Of Air Pollution Control Policies Based On Regression Discontinuity

With the rapid development of the economy,China has been suffering from serious air pollution.To solve the pollution problems caused by fireworks emissions during the Spring Festival and the automobile exhaust emission,policies aiming at banning fireworks during the Spring Festival and upgrading gasoline quality have been implemented respectively by the Chinese government.Based on the regression discontinuity（RD）design method,the impacts of these two policies on reducing the particulate matter（PM）concentration have been evaluated systematically under controlled meteorological conditions.Firstly,the impact of fireworks emissions on PM pollution in 29 Chinese cities has been quantitatively evaluated during the Spring Festival from 2015 to 2018.The results show that the concentrated fireworks display during the Spring Festival results in a significant increase in urban PM pollution concentration,and the increase of urban PM₁₀0 concentration is greater than that of PM2.5 concentration.Among the 29 cities,8 cities,including Beijing,Chongqing,Tianjin,Shenyang,Dalian,Harbin,Nanning,and Quanzhou,have experienced the most serious PM pollution during the Spring Festival.Due to the earlier implementation of the fireworks prohibition,the PM pollution concentration has not increased significantly during the Spring Festival in Shanghai,Shenzhen,Hangzhou,and Nanjing,and they are the top four cities with the best control effect on fireworks.Among the cities that have implemented the fireworks prohibition,the policy has shown a good effect of controlling PM pollution during the Spring Festival,except for Guangzhou,Quanzhou,and Foshan where the policy effect is poor.After Beijing,Jinan,and Suzhou first implemented the fireworks prohibition,the contributions of fireworks emissions on PM_2.5 and PM₁₀0 concentration during the Spring Festival decreased by75.7%and 82.1%,76.9%and 78.5%,81.0%,and 78.6%compared with the previous year,which indicates that the policy has significantly reduced the PM pollution during the Spring Festival.In the early years of the implementation of fireworks prohibitions in Chengdu and Jinhua,the PM pollution during the Spring Festival was still serious.Since the expansion of the banned area in 2018,PM pollution has been well controlled,and a certain lag exists in the effect of the policy in these two cities.Among the cities that have not implemented the policy,the concentration of PM pollutants has increased significantly due to the concentrated fireworks display,except for Ningbo,Kunming,and Wuxi,which have less pollution.Based on the empirical results,several specific suggestions are provided to assist the formulation and implementation of fireworks prohibitions policies.Secondly,the policy effect of upgrading gasoline quality on the PM concentrations in 47cities is systematically analyzed from two scales,namely,the macroscale and microscale.Macroscale analysis measures the impact on cities,and microscale analysis measures the impact on monitoring stations.The results tell that the policy has little effect on reducing PM pollution from the macroscale or microscale,while positive evidence does exist when focusing on pollution reduction for areas near main roads or junctions with heavy traffic in a case study.The findings suggests that the policy impact is affected by the heterogeneous pollution sources,and the potential of mitigating PM pollution by continually upgrading the quality of gasoline will be limited after five stages of upgrades.Finally,some policy recommendations are proposed for automobile exhaust pollution reduction and atmospheric PM pollution control.