数字经济、城市创新与雾霾污染

Digital Economy, Urban Innovation and Smog Pollution

建设数字中国与治理雾霾污染都是推动新时代经济高质量发展的重要战略之举。本文基于2011—2019年278个地级以上城市的面板数据,利用系统GMM及中介效应模型考察数字经济、城市创新对雾霾污染的作用机制。研究发现:(1)数字经济对雾霾污染具有显著的抑制效应,该结论在选取历史数据作为工具变量和“宽带中国”试点作为准自然实验等稳健性检验后仍然成立;(2)机制分析表明,数字经济通过城市创新效应、聚集驱动效应与结构优化效应三种重要渠道降低了雾霾污染水平;(3)数字经济的“梅特卡夫法则”在雾霾污染治理中得以验证,当数字经济超过门槛值时,城市创新对雾霾污染的“边际抑制效应”呈现逐渐递增的非线性特征;(4)异质性视角下,数字经济对雾霾污染的抑制效果因城市区位、人口规模及资源禀赋的不同而存在显著差异。

Building digital China and combating smog pollution are both important strategic initiatives to promote high-quality economic development of China in the new era. Based on the panel data of 278 cities and municipalities from 2011-2019, this paper examines the mechanisms of the digital economy and urban innovation on smog pollution with system GMM and mediating effect model. It is found that:(1) the digital economy has a significant inhibitory effect on smog pollution, which still holds after the robustness tests such as selecting historical data as instrumental variables and the "Broadband China" pilot as a quasi-natural experiment.(2) The mechanism analysis shows that the digital economy reduces the smog pollution through three important channels, i.e. urban innovation effect, agglomeration driving effect and structural optimization effect.(3) The threshold model reveals that when the digital economy exceeds the threshold, the marginal inhibitory effect of urban innovation on smog pollution has a non-linear characteristic of gradual increment.(4)From a heterogeneity perspective, the inhibitory effect of digital economy on smog pollution varies significantly depending on urban location, population size and resource endowment.