Evolution and drivers of green total factor productivity network structure in the Yangtze River economic belt from the perspective of urban agglomerations

Enhancing inter-city Green Total Factor Productivity (GTFP) connections is crucial for achieving high-quality development across the Yangtze River Economic Belt (YREB). This study constructs a spatial correlation network of GTFP for this region, analyzing its characteristics within the YREB and its three major urban agglomerations from 2005 to 2020 using social network analysis. QAP analysis is applied to explore the drivers of GTFP linkages between cities. Results reveal that (1) GTFP connectivity within the YREB strengthened continuously during the study period. The spatial correlation network density of GTFP in the YREB, Yangtze River Delta city cluster, middle reaches of Yangtze River City cluster and Chengdu-Chongqing City cluster showed a development trend of “rise-decline-rise," “rise-decline," “decline-rise," and “decline-rise-decline," respectively, and the network density always showed a “downstream > midstream > upstream" and"central city > non-central city.” (2) GTFP network's center shifted from Wenzhou to Suzhou, then to Changsha, and finally to Shanghai, with a growing multi-centrality trend in the Yangtze River Delta, dominant roles for Changsha and Wuhan in the middle reaches, and consistent leadership by Chengdu in the Chengdu-Chongqing agglomeration. (3) QAP analysis identifies urban agglomeration construction, industrial development, technological innovation, and environmental regulation as key drivers of GTFP spatial linkages, with urban agglomeration construction having the greatest impact. To advance GTFP and foster coordinated development in the YREB, this study recommends that central cities lead through strategic guidance and incentives for less developed areas, supporting agglomeration construction, technological innovation, and environmental protection as pathways to sustainable, high-quality growth.