Assessment of artificial lakes' impact on glacier conservation: Evidence obtained from stable isotope

Study region: This study focuses on the Yulong Snow Mountain (YLSM), a glacier region in the southeastern edge of the Qinghai-Tibet Plateau. Study focus: Stable isotopes were used to study transformation processes in different water bodies. HYSPLIT model was employed to analyze the trajectory paths and calculate the moisture flux. Finally, we used a binary linear mixed model to estimate the contribution of the artificial lake to precipitation in the glacial region. New hydrological insights for the region: Isotopic analysis of the hydrological system in YLSM has revealed distinct altitude-dependent and seasonal patterns. The moisture sources of YLSM exhibit pronounced seasonality, dominated by the Indian Ocean monsoon in summer and the westerly jet in winter, with the South Asian continental air mass as a persistent year-round contributor. Our findings demonstrate that vapor derived from artificial lakes contributes 8 %–42 % of the total snowfall in the glacial region of YLSM during the snowfall period, with a notable contribution of 8 %–16 % during the primary glacial accumulation period. This additional moisture input significantly decelerates local glacial retreat. In previous calculations of the local water cycle, the impact of artificial lakes has been underestimated. This study further expands local glacier protection technologies and deepens the understanding of the water cycle processes in high-altitude mountainous regions.