Evolution of agricultural water footprint and optimization of planting structure in the Hexi inland river basin

To assess the agricultural water consumption in the inland river basin of Hexi, based on the water footprint theory, the spatio-temporal evolution characteristics of the agricultural water footprint in this basin from 2011 to 2023 were analyzed. The multi-objective programming and LMDI model were used to analyze the planting structure and its influencing factors. The results show that the agricultural water footprint has been on the rise during the study period, with an average annual growth rate of 3.8%. Structurally, food crops (49.3%), economic crops (27.8%), and livestock products (22.5%) are the main components, while aquatic products account for a relatively small proportion (0.4%). After optimizing the planting structure of seven typical crops, the planting areas of wheat, corn, tubers, and oil crops decreased by 3.89×104 hm2, 6.11×104 hm2, 1.19×104 hm2, and 0.91×104 hm2 respectively, while the areas of Chinese herbal medicines, vegetables, and garden fruits increased by 1.75×104 hm2, 4.77×104 hm2, and 0.98×104 hm2 respectively. This optimization reduced the agricultural water footprint by 6.68×108 m3 and increased the economic benefits by 6.75×108 yuan. The analysis of influencing factors shows that economic factors play a major positive driving role in the growth of agricultural water footprint (contribution rate 58%), while technological (24.7%) and population factors (17.3%) have an inhibitory effect. The research provides a scientific basis for the efficient utilization and sustainable development of agricultural water resources in the basin.