Determination of the Suitable Lake Surface Area of Typical Terminal Lakes in Arid Regions

The continuous depletion of global groundwater resources has posed a serious threat to the ecological stability of terminal lakes in arid regions. However, accurate ecological assessment and water resource management of these lakes face a long-term key bottleneck—the determination of an appropriate lake surface area. Previous research has primarily focused on identifying the minimum interannual suitable lake surface area, with limited exploration of the suitable area range for lakes experiencing significant annual surface area fluctuations. Taitema Lake is located in the southeastern Tarim Basin of arid northwest China and serves as the terminal lake for both the Tarim and Cherchen Rivers. This study examines Taitema Lake, a continental terminal lake in an arid region. We developed a comprehensive ecological security evaluation system based on landscape structure, steady-state conditions, and habitat elements to establish the minimum suitable lake surface area threshold. By combining this with the threshold for maximum suitable lake surface area—when ecological water use efficiency peaks—we determined the interannual suitable lake surface area for Taitema Lake to be 33.7–154.4 km 2 . This study employed the MIKE 11 one-dimensional hydrodynamic model. Within the constraints of the lake surface area range determined by ecological water demand, we propose ecological dispatching plans for specific periods. During the green-up period (April to May), water is alternately transferred through either the Wenkuoer River or the old Tarim River at a flow rate of 24 m 3 /s, with a total conveyance volume of 1.3 × 10 8 m 3 . For the sowing period (August to October), a dual-channel approach is used where both rivers transport water simultaneously at 27 m 3 /s each, resulting in a total conveyance volume of 4.3 × 10 8 m 3 . This study offers valuable insights, supported by multi-scale models, for optimizing water resource allocation and ecological protection of lakes in arid areas.