数字经济发展如何改善城市碳排放？——基于长三角城市群的证据
How Can the Development of the Digital Economy Improve Urban Carbon Emissions?—Evidence Based on the Yangtze River Delta Urban Agglomeration

城市群低碳发展对中国“双碳”目标的顺利实现具有重要战略意义，数字经济时代则为区域碳减排带来新的助力和机遇。研究选取了2011~2020年长三角城市群27个城市的面板数据，基于熵值法测度数字经济发展水平，运用双向固定效应模型和机制检验实证分析数字经济对城市碳排放的影响与作用机制。研究表明：(1) 数字经济对碳排放影响显著，且呈现先增后减的倒“U”型特征。(2) 异质性分析表明，数字经济对碳排放的影响因数字经济发展水平、碳排放强度的不同表现出显著性差异。(3) 机制检验发现，数字经济通过促进产业结构升级和绿色技术创新，进而对碳排放表现出先增后减的非线性关系。文章丰富了“双碳”背景下长三角城市群数字经济对城市碳排放的理论研究，为长三角城市群因地制宜发展数字经济，推动城市低碳发展提供经验与政策启示。
The low-carbon development of urban agglomerations is of great strategic significance to the smooth realization of China’s “double carbon” goal. The era of digital economy brings new impetus and opportunities for regional carbon emission reduction. This study selects the panel data comprising 27 cities in the Yangtze River Delta urban agglomeration from 2011 to 2020, measures the level of digital economy development based on the entropy method, and uses the two-way fixed effect model and mechanism test to explore the influence and mechanism of digital economy on urban carbon emissions. The study demonstrates that: (1) The digital economy has a significant impact on carbon emissions, and it shows an inverted “U” type characteristic of increasing first and then decreasing. (2) Heterogeneity analysis manifests that the digital economy has a significant impact on carbon emissions due to the different levels of digital economy development and carbon emission intensity. (3) The mechanism test finds that the digital economy shows a non-linear relationship of increasing first and then decreasing carbon emissions by promoting industrial structure upgrading and green technology innovation. This paper enriches the theoretical research on the impact of digital economy on urban carbon emissions in the Yangtze River Delta urban agglomeration under the background of “double carbon” and provides experience and policy enlightenment for the Yangtze River Delta urban agglomeration to develop digital economy according to local conditions and promote urban low-carbon development.