Water Quality and Anthropogenic Pressures in Xinjiang’s Alpine Lakes: A Comparative Study of Tianchi, Sayram, and Bosten

Abstract

The alpine lakes of Xinjiang, China, represent critical ecological and economic resources facing growing anthropogenic pressures. This study conducts a comparative water quality assessment of Tianchi, Sayram, and Bosten Lakes to evaluate their ecological status and identify major drivers of environmental stress. Water samples collected during the peak tourism season were analyzed for nutrients, organic matter, heavy metals, and physicochemical indicators. The results reveal distinct profiles: Tianchi Lake exhibited oligotrophic characteristics with low nutrient concentrations, undetectable heavy metals, and absence of fecal coliforms, reflecting the effectiveness of stringent protective management. In contrast, Bosten Lake showed signs of eutrophication, and its Chemical Oxygen Demand indicates significant organic pollution from non-point sources; Sayram Lake displayed geochemical anomalies, characterized by elevated arsenic concentrations and alkaline pH, likely influenced by regional geology, together with moderate organic pollution. This study concludes that the environmental challenges facing these lakes are different. Tianchi requires consistent management to preserve its state, Bosten urgently needs integrated watershed management to control diffuse pollution, and Sayram demands further investigation into the source of arsenic and the ecological impacts of its high pH. The results highlight the necessity for lake-specific conservation strategies to ensure the long-term sustainability of these vital ecosystems amidst increasing human activity.