数字经济的减污降碳协同作用及机制——基于地级市数据的实证检验

The synergistic effect of digital economy on pollution and carbon reduction and the influence mechanism:An empirical test based on prefecture-level city data

【目的】数字经济是实现中国新旧动能转换的重要着力点,与经济社会各领域广泛融合和不断发展,赋予中国减污降碳协同效应新的动力机制,在推进”美丽中国“建设与实现”双碳“气候承诺的关键窗口期,研究数字经济发展的减污降碳协同作用是实现绿色和高质量发展背景下的重要命题。【方法】本文基于277个地级及以上城市的面板数据,运用固定效应、中介效应等方法,从多维度检验数字经济的减污降碳协同作用及其中介机制。【结果】研究发现:①数字经济发展显著促进了减污降碳协同效应,采用工具变量法、剔除直辖市等方法进行内生性和稳健性检验后结论仍成立。②选取“宽带中国”战略作为外生政策冲击,以多期DID模型评估数字经济对减污降碳协同效应的影响,回归结果表明“宽带中国”战略对减污降碳协同效应具有显著正向影响。③机制分析发现,提高技术水平、优化产业结构、增强公众环境监督可以促进数字经济的减污降碳协同效应。④区域异质性分析表明,东部地区和非资源型城市数字经济对减污降碳协同效应的影响更显著,而在中西部地区和资源型城市中影响不显著,这主要与区域之间的数字经济发展水平不平衡有关。【结论】应大力发展数字经济,加快新型基础设施建设,从政府、企业和公众多维度加强环保意识和行动,依托各地区资源比较优势,充分释放数字经济的潜能,实现减污降碳协同增效。

[Objective]The digital economy is an important focus for realizing the transformation of China’s old and new development momentums,and its extensive integration and continuous development within various economic and social fields have given China a new power dynamic for the synergistic effect of pollution reduction and carbon reduction.In the critical window of promoting the construction of“Beautiful China”and realizing the“dual-carbon”climate commitment,the study of the impact of the development of the digital economy on the synergistic effect of pollution reduction and carbon reduction is an important proposition in the context of realizing green and high-quality development in China.[Methods]Based on the panel data of 277 prefecture-level and above cities,this study examined the impact of the digital economy on the synergistic effect of pollution reduction and carbon reduction and its mediation mechanism in multiple dimensions by using fixed effect and mediation effect models.[Results]The findings are as follows:(1)The development of the digital economy significantly contributes to the synergistic effect of pollution reduction and carbon reduction,and the conclusions still hold after endogeneity and robustness tests using the instrumental variable method and excluding the four provincial-level municipalities.(2)The“broadband China”strategy was chosen as an exogenous policy shock,and the multi-period difference-in-differences(DID)model was used to evaluate the impact of the digital economy on the synergistic effect of pollution reduction and carbon reduction.The regression results show that the“broadband China”strategy had a positive and significant impact on the synergistic effect of pollution reduction and carbon reduction.(3)The test results of the mechanism analysis show that the development of the digital economy can promote the synergistic effect of pollution reduction and carbon reduction by improving technologies,promoting industrial structure upgrading,and enhancing public environmental supervision.(4)The analysis of regional heterogeneity showed that the impact of the digital economy on the synergistic effect of pollution reduction and carbon reduction is more significant in the eastern region and non-resource-based cities,while the impact is not significant in the central and western regions and resource-based cities,which is mainly related to the uncoordinated level of digital economy development among regions.[Conclusion]We should vigorously develop the digital economy,accelerate the construction of new infrastructures,strengthen environmental awareness and action of the government,enterprises and the public,and fully unleash the potential of the digital economy based on the comparative advantages of the resources in each region,so as to realize synergies in reducing pollution and carbon emissions.