Suitable Lake Water Area for Ecological Security of Terminal Lakes in Xinjiang, China

Terminal lakes are crucial to maintaining ecological balance in arid and semi-arid regions. However, these lakes are increasingly facing severe ecological degradation due to human activities and climate change. This study aims to provide a sustainable management solution for ecological security by determining the suitable water surface area of terminal lakes. We selected eight major terminal lakes in Xinjiang, including Bosten Lake, Lake Ebinur, Lake Ailik, Manas Lake, and Lake Ayding, and analyzed the changes in water surface area over the past 30 years. This research proposes a new method based on ecosystem safety demands to assess the minimum ecological water levels required to maintain the health of these lakes. The study utilizes remote sensing images, ecological security assessments, and hydrological data to analyze the water surface changes, vegetation growth, and ecological health of these lakes. Main findings include the following: (1) The water surface area of most lakes fluctuates significantly, with Bosten Lake maintaining a water surface area between 920 and 1100 km2, while Lake Ebinur decreased sharply from 884 km2 in 2003 to 350 km2 in 2022. (2) The proposed method calculates the suitable water surface area for each lake, ranging from 25 km2 (Lake Ayding) to 1050 km2 (Bosten Lake). (3) The proposed method provides precise recommendations that can maintain ecological stability while optimizing water resource usage. (4) Some of the findings have already been adopted by local government departments and are applied to water resource management in Xinjiang. This study provides a new approach for defining a suitable water surface area based on ecological security demands and offers valuable insights for the sustainable management of terminal lakes in arid regions.