Abstract:

This study focuses on the Crescent Spring Area at the western end of the Hexi Corridor. Through sample collection experiments, the research systematically analyzed hydrochemical characteristics, environmental isotopes, and hydrogeochemical processes within the study area. The results indicate that mountain water, originating from atmospheric rainfall and glacial meltwater, is the primary source replenishing the diving pool in the area, with a close causal link between the two. Additionally, the local area is affected by the fault structure or cross-flow and receives lateral replenishment from the deep underground runoff in front of the Qilian Mountains. The evaporation effect of groundwater in the Danghe irrigation area is weak, primarily discharging through artificial mining. Other groundwater burial areas mainly discharge through evaporation and transpiration. The chemical composition of groundwater is influenced by the karst filtration involving carbonate and silicate. Key factors controlling groundwater salinity include the dissolution of rock salt, gypsum, and partite rocks, as well as the precipitation of calcite and dolomite, along with evaporation. Various degrees of mixing occur during the water cycle in the basin. Overall, these research findings provide a scientific basis for the ecological protection and restoration of Crescent Lake.

Key words: Crescent Lake, groundwater systems, water chemical characteristics, environmental isotopes