Abstract: To address the conflicting water demands by life, production, and ecology in arid and desert regions, this study focuses on three major tributaries (the Aksu, Hotan, and Yarkand Rivers) of the Tarim River and its mainstream, where significant issues have emerged－excessive evaporation and seepage losses over the entire basin, and imbalanced water distribution between the tributaries and the mainstream. We develop simulation and optimization models for water resource allocation through coupling with the layout and adjustment of major water conservancy projects, and solve them for the years of 2018, 2025, and 2035. To address the issues above, engineering measures are explored for reduction and control of the evaporation and seepage losses in river channels and plain reservoirs. Results show that water resource allocation aimed at replacing plain reservoirs with mountain reservoirs effectively reduces evaporation and leakage losses, with an increase in water supply potential of 350 million m3 and 496 million m3 and an irrigation area increase of 31.3 thousand ha and 45.2 thousand ha in years of 2025 and 2035, respectively. This greatly alleviates the conflicts between water uses from the source streams and main stream, and helps promote regional economic and social development and implement the national food security strategy.

Key words: water resource allocation, reduction and control of water losses, water losses of rivers and reservoirs, water supply potential, Tarim River basin