Spatiotemporal dynamics and driving mechanisms of industrial green water resource efficiency in China's Yangtze River Economic Belt

Promoting industrial green water resource efficiency (IGWRE) is critical for reconciling economic growth with water sustainability in rapidly industrializing basins. This study proposes an integrated 'ecological-economic' evaluation framework within a Super-SBM-DEA model that incorporates undesirable outputs to assess IGWRE across 11 provinces in China's Yangtze River Economic Belt (YREB) from 2014 to 2023. Combining kernel density estimation, ArcGIS spatial mapping, and spatial Durbin models (SDM), we reveal three key findings: (1) IGWRE exhibits a significant long-term upward trend but with persistent regional heterogeneity and recent short-term fluctuations, with downstream regions (Shanghai, Jiangsu, Zhejiang) maintaining efficiency leadership while upstream provinces such as Chongqing and Sichuan demonstrate remarkable catch-up effects. (2) Spatial correlation analysis confirms strong spatial dependence, with technology diffusion generating stronger positive spillovers than pollution transfer. (3) SDM decomposition identifies technological progress as the primary driver, while economic development inhibits local efficiency due to the 'resource curse.' Environmental regulation enhances local IGWRE but triggers negative spillovers, and industrial structure optimization uniformly benefits efficiency. Social investment boosts local efficiency yet suppresses neighboring regions. These findings underscore the necessity for differentiated regional policies, inter-provincial technology transfer mechanisms, and basin-wide industrial water rights trading to reconcile economic growth with water sustainability.