城市机动车限行政策对雾霾污染治理的成效分析

Analysis of the effects of driving restriction policies in controlling haze pollution

自2013年以来,中国频繁出现大规模和持续性的雾霾天气,诸多地方政府不得不采取一系列措施来治理雾霾污染,其中包括广为效仿的机动车限行政策,但其实施效果在不同城市却显示出较大差异性。本文对实施限行政策的11个典型城市的PM2.5浓度进行结构突变点的筛选,并通过控制风速、雨水、湿度、温度等气象因素,建立多元回归模型以分析PM2.5浓度与机动车限行政策的相关性。结果发现,气象因素对于各城市的雾霾污染有着不同的影响。其中,风级、降雨、温度在大部分城市是负向且显著的影响,湿度在部分城市是正向且显著的影响。本文根据限行效果的不同将11个城市分为三类:限行有效、限行无效和限行效果不显著城市。为了进一步考察不同类型的典型城市限行的效果为何不同,选取了北京、天津、西安三个城市从经济、产业、能源以及交通等四个维度进行对比分析,发现不同类型的城市由于城市形态及雾霾成因各不相同,雾霾污染的治理措施也需要"因地制宜"。基于此,本文对不同形态的城市雾霾污染治理提出以下建议:(1)当城市发展处于高经济-低污染形态时,机动车限行政策是雾霾污染治理的有效手段,但治理的根本在于控制城市机动车保有量,优化城市发展职能,降低城市人口密度;(2)当城市发展形态处于高经济-高污染形态时,机动车限行政策不是城市治理雾霾污染的最有效手段,政府应加快产业结构转型升级,优化能源消耗结构,加大污染治理投资力度;(3)当城市发展处于中、低经济-高污染阶段时,机动车限行政策无效,城市发展应注重优化投资结构,转变产业发展模式。

As there has been more frequent,large-scale and persistent haze weather in China since 2013,many local governments had to take series of measures to control the haze pollution.Among which,the driving restriction policy has been widely adopted,and it has shown varied effects in different cities.This study attempts to conduct data mining on the data of PM 2.5 concentration of 11 provincial capital cities in China with driving restriction policies,and find the structural breaks points.Multivariate regression model is applied to explore the correlation of PM 2.5 and restriction policy by controlling the climate factors such as wind level,rainfall,humidity and so on.The results show that meteorological factors in each city have a different impact on haze pollution.Among them,wind level,rainfall and temperature have significant negative impact in most cities and humidity has significant positive impact in some cities.As for the different effects of driving restrictions,the 11 provincial capital cities can be divided into three categories,the effective,the ineffective and the insignificant.In order to investigate the reasons behind the differences,Beijing,Tianjin and Xi’an are chosen in each category for comparative analysis in four dimensions:economy,industrial structure,energy consumption and transportation condition.It is found that the fundamental cause of haze pollution varies in different cities,therefore different measures need to be taken to ease the haze pollution rather than rely simply on the driving restriction policy:①When the city is at the status of high-economic development with low-pollution level,the driving restriction policy is an effective means to control haze pollution,the local government is suggested to control the quantity of motor vehicles,optimize urban development functions,and reduce urban population density.②When the city is at the status of high-economic development with high-pollution level,the driving restriction policy is not the most effective way to control haze pollution.The local government should emphasize more on speeding up the transformation and upgrading of industrial structure,optimizing the energy consumption structure and increasing investment in pollution control.③When the city at the status of medium/low-economic development and high-pollution level,the driving restriction policy is rather ineffective.Urban development should focus on optimizing investment structure and upgrading industry development mode to be more sustainable.