数字经济影响城市群绿色技术创新的机制及空间溢出效应

An Analysis of the Mechanism and Spatial Spillover Effect of Digital Economy on Green Technology Innovation in China’s Urban Agglomeration

数字经济与绿色技术创新是实现中国式现代化的重要举措,基于2011~2020年中国10个城市群157个城市数据,实证分析数字经济对城市绿色技术创新的影响,检验了中心城市数字经济对城市群周边城市绿色技术创新的空间溢出效应和辐射带动作用。结果显示:数字经济显著促进了城市绿色技术创新,用工具变量法、泊松回归和替换被解释变量分析后,结论依然稳健。中介效应分析表明,数字经济通过规模效应和技术效应带动了城市绿色技术创新。采用空间杜宾模型,发现数字经济对城市绿色技术创新的积极影响存在显著空间溢出效应,这一结论在分析中心城市对城市群外围城市影响时仍然成立。通过构建中心城市辐射效应变量,发现中心城市对城市群周边城市的绿色技术创新有明显的辐射带动作用。异质性分析表明,中心城市数字经济对周边城市绿色技术创新的空间溢出效应和辐射效应均存在城市群异质性,长三角、珠三角、京津冀城市群中心城市的空间溢出效应和辐射带动作用更为明显。基于这些结论,提出要加快城市数字经济发展和数字技术普及,强化城市群中心城市数字经济和绿色技术创新引领作用,促进城市群绿色技术创新协同发展。

Digital economy and green technology innovation are important measures to pave China’s Path to Modernization.Based on the data of 157 cities in 10 urban agglomerations in China from 2011 to 2020,this paper empirically analyzes the impact of digital economy on urban green technology innovation,and examines the spatial spillover effect and radiation effect of digital economy in central cities on green technology innovation in cities around the urban agglomerations.The results show that digital economy has significantly promoted urban green technology innovation.Tested by the instrumental variable method,Poisson regression and replacement of the explained variable analysis,the conclusion is still robust.The analysis of intermediary effect shows that digital economy drives urban green technology innovation through scale effect and technology effect.Within the Spatial DubinModel,it is found that the positive impact of digital economy on urban green technology innovation has a significant spatial spillover,which is still valid in the case of the impact of central cities on the surrounding cities outside the urban agglomeration.By constructing the radiation effect variable of central cities,it is found that the central cities have obvious radiation and driving effects on the green technology innovation of the cities around the urban agglomeration.The heterogeneity analysis shows that the spatial spillover and radiation effect of the digital economy of the central city on the green technology innovation of the surrounding cities are heterogeneous in urban agglomeration,and the spatial spillover and radiation driving effect of the central cities of the Yangtze River Delta,the Pearl River Delta,and the Beijing-Tianjin-Hebei urban agglomeration are more obvious.Therefore,this paper proposes to accelerate the development of urban digital economy and the popularization of digital technology,strengthen the leading role of digital economy and green technology innovation in central cities of urban agglomeration,and promote the coordinated development of green technology innovation in urban agglomeration.