空气污染对城市化进程的反馈效应

Feedback effect of air pollution on the process of urbanization

空气污染对城市化进程的反馈效应分析是完善空气污染与城市化互动机理研究框架的关键,亦是协同推进生态文明建设与新型城镇化的重要参考。文章利用夜间灯光数据反映城市化综合水平,并选取2013-2018年中国281个地级及以上城市的年均PM2.5浓度来衡量空气污染,探究空气污染对城市化进程的反馈效应及其作用机理,并在此基础上进行异质性分析。研究表明:(1)空气污染对城市化水平存在显著的负向反馈效应,此结论在一系列稳健性检验与内生性检验下依然成立。(2)城市人口规模与经济发展是空气污染影响城市化进程的两个重要作用机制。空气污染对城市人口规模、经济发展均存在显著的负面作用,进而对城市化产生负向反馈效应。(3)空气污染对城市化的反馈效应存在城市异质性。空气污染对北方城市、中部与东北地区、大中城市的城市化进程存在更为显著的负向反馈效应;此外,二者在秦岭-淮河线以南地区呈现出显著的"倒U型"曲线关系,说明空气污染对城市化进程的反馈效应存在非线性特征。针对上述研究结论,文章认为,污染气体减排仍是当前缓解空气污染对城市化进程负向反馈效应的有效措施,而集约高效地推进城市化进程更是根本举措;实施积极的人才引进政策、以创新改变粗放的经济增长结构以缓解空气污染对城市化的负向反馈效应;此外,在对大中城市进行污染防治的同时,要警惕小城市的空气污染发展态势。

The analysis of the feedback effect of air pollution on the process of urbanization is the key to perfecting the research framework of the interaction mechanism between air pollution and urbanization,and is also an important reference for the collaborative promotion of ecological civilization construction and new urbanization.In view of this,this article used night time light data to reflect the comprehensive level of urbanization,selected the annual average PM2.5 concentration of 281 prefecture-level cities and above in China from 2013 to 2018 to measure air pollution,explored the feedback effect of air pollution on the process of urbanization and mechanism of action,and analyzed the heterogeneity on this basis.The results of the study showed that:(1)Air pollution had a significant negative feedback effect on the level of urbanization.This conclusion was still valid under a series of robustness tests and endogenous tests.(2)Urban population scale and economic development were two important mechanisms of air pollution affecting the process of urbanization.Air pollution had significant negative effects on urban population scale and economic development,and further producing negative feedback effects on urbanization through these two channels.(3)The feedback effect of air pollution on urbanization had urban heterogeneity.Air pollution had a more significant negative feedback effect on the urbanization process of northern cities,central and northeastern regions,and large and medium-sized cities;in addition,the two demonstrated a significant’inverted U-shaped’curve relationship in the south area of the Qinling-Huaihe line,indicating that the feedback effect of air pollution on the urbanization process had nonlinear characteristics.In response to the above research conclusions,this article believes that the reduction of pollutant gas is still an effective measure to alleviate the negative feedback effect of air pollution on the urbanization process,and the intensive and efficient promotion of the urbanization process is a fundamental measure;it is essential to implement a proactive talent introduction policy and use innovation to change the extensive economic growth structure to alleviate the negative feedback effect of air pollution on urbanization.Furthermore,in the process of preventing and controlling pollution in large and medium cities,we must be alert to the development trend of air pollution in small cities.