Scientific monitoring of environmental regulation intensity and identification of its obstacle factors are critical pathways to enhance regional environmental resilience and promote the coordinated sustainable development of society, economy, and environment. This study constructs an environmental regulation intensity index system based on a tripartite framework encompassing government-led initiatives, market incentives, and public participation. Employing the CRITIC-entropy weight combination method, we measure the environmental regulation intensity across provinces in the Yangtze River Economic Belt from 2012 to 2022, systematically analyzing its spatiotemporal differentiation characteristics and obstacle factors. The findings reveal that: (1) Environmental regulation intensity exhibited a fluctuating upward trend during the study period, increasing from 0.359 to 0.468 (annual growth rate: 2.19%), with significant regional synergistic effects. (2) Spatial heterogeneity followed a downstream > midstream > upstream gradient (decadal means: 0.515, 0.447, and 0.401, respectively), while the midstream region demonstrated the fastest growth (3.64%), contrasting with the upstream region's lag in both mean value (0.401) and growth rate (2.87%). (3) The global Moran’s index indicates intensifying spatial agglomeration and enhanced regional connectivity, with local spatial patterns dominated by "high-high" and "low-low" clusters, where "high-high" clusters expanded progressively. (4) The average constraint intensities of government-led measures, market incentives, and public participation were 43.45%, 34.67%, and 21.89%, respectively. Targeted policy recommendations are proposed to address these findings. |