Comprehensive Assessment of Ecological Water Replenishment Effects from Inter-basin Water Transfer in Arid Inland River Basins

Inter-basin water transfer is a crucial measure for improving ecological environments in arid regions, yet comprehensive quantitative assessments of its ecological water replenishment effects remain insufficient. Therefore, this study examines the inter-basin ecological water replenishment from the Yellow River Basin to the Shiyang River inland basin via the Jingtai Electric Irrigation Project. An evaluation system with eight indicators—water transfer volume, groundwater depth, groundwater storage change, ecological replenishment volume, water area, replenishment efficiency, population growth rate, and urbanization rate—was constructed from the "water resources-water ecology-society" perspective. The entropy weight method was used to determine indicator weights, and comprehensive effects from 2011 to 2024 were systematically assessed. Results show that over the 14-year period, cumulative water transfer reached 1.527 billion m³, groundwater depth recovered by 0.45 m, and the water area of Qingtu Lake, a terminal lake, expanded by 17.65 km² with an increase of 176.5%. The comprehensive evaluation index increased by 140.8%, rising from 0.30 in 2011 to 0.72 in 2024, demonstrating significant achievements in ecological restoration, groundwater recharge, and human settlement improvement. Although ecological water replenishment efficiency is constrained by conveyance losses and regional population continues to decline, systematic improvements in core indicators such as water transfer volume, groundwater, and water area have driven a leapfrog enhancement of comprehensive benefits. The research findings fully validate the comprehensive benefits and sustainability of inter-basin ecological water replenishment, providing scientific basis for safeguarding the ecological security of key lakes in arid basins.