Dynamic Spatial Association Network and Formation Mechanisms of Environmentally Adjusted Water Use Efficiency in the Planting Industry of the Yangtze River Economic Belt, China: Implications for Sustainable Agricultural Water Management

Improving environmentally adjusted water use efficiency in the planting industry (EAWUE) is important for balancing agricultural production, water conservation, and water environmental protection. Using panel data for 101 prefecture-level cities in the Yangtze River Economic Belt during 2011–2023, this study integrates a Super-SBM model with undesirable outputs, a modified gravity model, social network analysis, and a temporal exponential random graph model (TERGM) to examine EAWUE dynamics, spatial association networks, and formation mechanisms. The results show that EAWUE improved overall, although spatial disparities remained evident. The spatial association network became denser and more connected, with inter-city linkages expanding from local associations to broader cross-regional and multi-node interactions. The Yangtze River Delta maintained a prominent core position, cities in the middle reaches played stronger bridging roles, and cities in the upper reaches showed increasing participation, forming four functional block types. Network tie formation was statistically associated with endogenous network structures, node attributes, spatial constraints, and temporal dependence. Reciprocity, transitive structures, and network persistence showed positive associations with tie formation, whereas geographic distance showed a negative association. Resource endowment, rural human capital, and industrial structure upgrading generally showed positive associations, while economic development and government support exhibited heterogeneous associations with sending and receiving roles. Sensitivity and robustness tests generally supported the main structural findings. These findings highlight the need for differentiated prefecture-level governance, stronger agricultural water conservation and non-point source pollution control, improved cross-regional coordination, and fuller use of core nodes and functional blocks to support sustainable agricultural water management.