城市群扩容是否有利于产业升级——来自长三角县域的经验证据

Will the Enlargement of City Clusters Boost Industrial Upgrading? Empirical Evidence from Counties in the Yangtze River Delta

以都市圈和城市群建设为代表的区域一体化是充分发挥我国超大规模市场优势和内需潜力,推动构建以国内大循环为主体、国内国际双循环相互促进的新发展格局的重要引擎。文章以长三角县域为分析单元,使用合成控制法和基于倾向得分匹配的双重差分方法,检验并比较了长三角区域一体化对城市群内部县域产业升级的异质性影响。研究发现:整体来看,长三角扩容推动了整个城市群的产业升级。从不同区域来看,无论是原位城市还是新进城市,其市辖区的产业升级效应均十分明显;原位城市中县级市的产业技术复杂度的提升远高于新进城市,但整体低于市辖区,而新进城市中县的产业升级效应显著大于原位城市。城市群扩容主要通过促进要素自由流动、打破市场分割以及技术创新扩散等路径推动区域产业升级,其中打破行政壁垒后生产要素在更大范围的畅通流动和配置优化是城市群扩容带动产业升级的主要原因。

With the great changes in the external environment of China’s economic and social development,the competition among big powers become more intense,and the international economic circulation is restricted.Meanwhile,the COVID-19 epidemic has seriously affected the international industrial chains and supply chains,and shrinking external demands as well as frictions in international economic trade have forced China to accelerate the construction of a new development pattern,with the big domestic circulation as the main body and the dual domestic and international circulation as the mutual promotion.Under this background,the utilization and integration of domestic market brought by regional integration is of great significance to promote industrial upgrading.This paper focuses on the industrial upgrading of city clusters,and tries to identify whether the enlargement of city clusters is an effective way to stimulate regional industrial upgrading.This paper treats the enlargement of the Yangtze River Delta in 2010 as a quasi-natural experiment,uses the synthetic control method(SCM)and the PSM-DID method to simulate and compare the way of industrial upgrading of three regions,including whole counties(cities,districts),incumbent counties(cities,districts)and new counties(cities,districts)within the integration of the Yangtze River Delta,and draws a robust conclusion that the enlargement of the Yangtze River Delta promotes the industrial technical complexity of the three types of counties(cities,districts).Furthermore,this paper investigates the heterogeneity among counties,county-level cities and districts,and finds that the enlargement has the greatest impact on districts.Specifically,the promotion effect of districts in incumbent cities is greater than that in new cities;the industrial upgrading effect of county-level cities in incumbent cities is greater than that in new cities;for county-level regions,the industrial structure adjustment of counties in incumbent cities is smaller,and the industrial upgrading effect of counties in new cities is more obvious.Further research confirms that the promotion effect originates from regional integration,which leads to reallocating resources optimally and improving the utilization efficiency of resources among different counties(cities,districts).From the perspective of resource allocation,the industrial upgrading effect of the enlargement of city clusters is mainly achieved through several specific channels such as giving play to the market scale effect,promoting technological innovation,strengthening government cooperation,and so on.The integration of the Yangtze River Delta not only undertakes the great historical mission of exploring the way for the new development pattern of dual domestic and international circulation,but also shoulders the important task to be the pioneer of China’s innovation in science,technology and industry.To promote the development of regional integration,the key lies in how to effectively reduce the flow barriers of factors among regions through institutional innovation,so as to provide a strong driving force for regional industrial upgrading and building the world’s advanced manufacturing clusters.