Spatiotemporal evolution and influencing factors of agricultural water use efficiency in the Yellow River Basin

ABSTRACT Graphical abstract showing the spatial heterogeneity of agricultural water use efficiency (AWUE) in the Yellow River Basin, key research methods (super-efficiency SBM, Malmquist index, and GTWR model), efficiency trends driven by technological change, and targeted policy recommendations for upstream, midstream, and downstream regions. Agricultural water use efficiency (AWUE) is defined as the ratio of agricultural output to agricultural water input, which reflects the level of rational and efficient utilization of water resources in agricultural production, and is critical for achieving water-food-energy nexus sustainability in water-scarce regions. This study employs a super-efficiency slacks-based measure (SBM) model and the Malmquist index to quantify AWUE and its spatiotemporal evolution in the Yellow River Basin (YRB), China, from 2003 to 2017. A geographically and temporally weighted regression (GTWR) model was then applied to identify the key driving factors. Results show that AWUE in the YRB remained low (average 0.80), with significant spatial heterogeneity: Shandong and Sichuan achieved efficiency >1.0, while Qinghai and Ningxia were <0.6. AWUE improved marginally over time, mainly driven by technological change rather than efficiency change. GTWR results reveal that water-saving irrigation area and gross domestic product (GDP) per capita positively influenced AWUE in most provinces, while annual sunshine hours had a negative effect.