中国城市PM_(2.5)减排效率的区域差异及其影响机制

Regional differences in PM_(2.5) emission reduction efficiency and their influencing mechanism in Chinese cities

为打好环境污染防治攻坚战,促进经济高质量发展,中国各级政府不断加大环境污染的防治力度。首先,文章采用2003—2018年中国260个地级市的面板数据,运用共同前沿技术和Hybrid-Dynamic-DEA模型测算了中国城市层面的PM_(2.5)减排效率。其次,在考察了不同城市要素禀赋结构存在异质性的基础上,深入分析了经济发展水平对中国城市PM_(2.5)减排效率的影响。研究结果显示:①中国PM_(2.5)减排效率整体偏低,年均值仅为0.126,大气污染减排压力巨大。②样本期内中国PM_(2.5)减排效率呈现出缓慢上升再下降的过程。区域间PM_(2.5)减排效率存在明显的区域异质性,表现为东部地区最高,其次是东北部,再次是西部,中部地区最低。③从整体来看经济发展水平对PM_(2.5)减排效率具有显著的促进作用。从异质性角度来看,在10%到90%分位数之间经济发展水平对PM_(2.5)减排效率的影响随着分位点的升高而升高。在考虑了PM_(2.5)减排效率的指标更换、外生工具变量的构造等方面后,结果依然稳健。④机制研究结果表明城市要素禀赋结构的差异会作用于地区经济发展水平,进而影响到PM_(2.5)减排效率。因此,各地政府要结合各自城市的要素禀赋结构和比较优势,制定适应的大气污染环境治理政策,不能纯粹依靠政府的行政化管理手段,避免采取“一刀切”或“照搬照抄”的环境治理方式;要实施差异化的大气污染环境治理政策,对于东部沿海城市应不断完善产业发展政策,提高自身的环境治理能力。中西部地区城市应加快引进沿海城市的先进管理经验,激励企业进行绿色技术或工艺的改造升级,努力提高经济增长的质量。

In order to win the tough battle against environmental pollution and promote high-quality economic development,China’s governments at all levels have been stepping up efforts to prevent and control environmental pollution.Based on the panel data of 260 cities in China from 2003 to 2018,this paper first adopted the Meta-Frontier method and the Hybrid Dynamic DEA model to measure the urban PM_(2.5) emission reduction efficiency in China.Then,on the basis of the heterogeneity in the structure of different urban factor endowments,this paper further analyzed the impact of economic development level on the efficiency of PM_(2.5) mission reduction in these Chinese cities.The results of the study showed that:①China’s overall PM_(2.5) emission reduction efficiency was at a low level,with an annual average value of 0.1257,and there was a huge pressure to reduce air pollution emissions.②During the sample period,China’s PM_(2.5) emission reduction efficiency showed a process of increasing slowly and then decreasing.There was obvious regional heterogeneity in PM_(2.5) emission reduction efficiency between the four major regions in China,i.e.,the eastern region had the highest efficiency of PM_(2.5) emission reduction,followed by the northeastern region,then the western region and the central region.③In general,the level of economic development played a significant role in promoting the efficiency of PM_(2.5) emission reduction.From the perspective of heterogeneity,the impact of the economic development level on PM_(2.5) emission reduction efficiency increased with the increase of the percentile between 10%and 90%.After changing PM_(2.5) emission reduction efficiency indicator and constructing exogenous tool variable,this paper found that the influence of economic development level on PM_(2.5) emission reduction efficiency was still significant.④The results of mechanism research showed that the differences of urban factor endowment structure had an impact on the efficiency of PM_(2.5) emission reduction efficiency through affecting the level of regional economic development.Therefore,local governments should take the factor endowment structure and comparative advantage of their respective cities into account to formulate adaptive policies for air pollution control and avoid adopting the‘one-size-fits-all’or‘copy-all’environmental control methods.Besides,local governments should implement differentiated environmental governance policies for air pollution.China’s eastern coastal cities should constantly improve their industrial development policies and their own environmental governance capabilities.And for cities in China’s central and western regions,the introduction of advanced management experience from coastal cities should be accelerated,and enterprises should be incentivized to upgrade green technologies or processes in an effort to improve the quality of economic growth.