Can regional integration promote industrial green transformation? Empirical evidence from Yangtze River Delta Urban Agglomeration

This paper analyzes the spatial-temporal evolution of regional integration and industrial green transformation and empirically investigates the impact of regional integration on industrial green transformation using prefecture-level panel data of cities in the Yangtze River Delta Urban Agglomeration (YRDUA) from 2006 to 2018. The major findings are as follows: (1) during the observation period, the level of regional integration rose in general, with regions with a high integrated level expanding northward, southward, and westward in the YRDUA. Industrial green transformation has the property of path-dependent and a spatial lock-in pattern of "high in the east, low in the west." (2) There exists a considerable U-shaped relationship between regional integration and industrial green transformation; most cities in the YRDUA have crossed the inflection point in terms of integrated development. Regional integration has a positive spillover effect on the industrial green transformation of the surrounding areas, which diminishes as geographic distance increases. When the level of regional integration becomes excessive, it also impedes surrounding areas' industrial green transformation. (3) Regional integration can affect industrial green transformation by promoting economic scale expansion, industrial structure upgrading, and technological progress. At this moment, the economic scale is the most significant mediating factor. With the advancement of regional integration, technological progress will become critical. This paper provides a rationale for understanding industrial green transformation from the perspective of regional integration and enriches theoretical and empirical studies on ecological civilization construction and green development in urban agglomerations.