Effects of environmental regulation on green total factor productivity under different regional synergistic...

Environmental regulation (ER) is crucial for promoting green total factor productivity (GTFP) and relies on efficient resource aggregation, flow, and allocation across regions for its implementation. It is therefore essential to examine the effects of ER on GTFP within the framework of regional synergistic development (RSD) to support China's green economic growth. This study quantifies the GTFP of 283 Chinese prefecture-level cities from 2008 to 2022 and investigates the impact of ER on GTFP and its underlying mechanisms under RSD conditions using panel threshold regression, mediating effect models, and a dynamic spatial Durbin model. The results demonstrate that: first, China's GTFP exhibits a fluctuating-growth-fluctuation pattern, accompanied by significant regional disparities; second, the effects of ER on GTFP have a significant positive and increasing marginal effect non-linear characteristic under varying thresholds of RSD; third, when RSD is highly developed, ER enhances GTFP through industrial structure upgrading and local governments competition, whereas at lower RSD stages, government competition weakens ER's positive effect; finally, significant positive spatial spillover effects are observed, and ER and RSD interact synergistically to enhance GTFP. This study offers new insights into the relationship between ER and GTFP and provides actionable guidance for developing countries facing the dual challenges of economic growth and environmental governance.