A spatial effect study on digital economy affecting the green total factor productivity in the Yangtze River Economic Belt

With the advent of the Industry 4.0 era, the digital economy (DE) has become a new driver of sustainable development. This paper focuses on DE's green and environmental value. Based on the panel data of 108 cities in the Yangtze River Economic Belt from 2011 to 2019, we evaluated the temporal and spatial evolution of DE and green total factor productivity (GTFP). The spatial Durbin model analyzes the direct and spatial spillover effects of DE on GTFP, the green efficiency change (GEC), and the green technical change (GTC). The results show that the DE maintains a stable growth trend. GTFP and GTC show a similar fluctuating upward trend, while GEC shows a fluctuating downward trend. Both DE and GTFP show a clustering trend of "high in the lower reaches and low in the upper and middle reaches" and a typical center-periphery pattern over time. Second, for the direct effect, DE has a significant positive impact on GTFP, mainly on GTC rather than GEC. The promotion effect is stronger at the new normal stage, in the lower reaches, and the three major urban agglomerations. Third, for the spatial spillover effect, DE has a trickle-down effect on GTFP and GTC and a siphon effect on GEC, more potent at the new normal stage and in the lower reaches. Compared with peripheral cities, DE has significant trickle-down effects on GTFP, GTC, and GEC in the three major urban agglomerations.