Interaction between surface water and groundwater and hydrochemical characteristics in the typical watersheds of the Qaidam Basin

Subjects: Geosciences >> Hydrology submitted time 2022-12-20 Cooperative journals: 《干旱区研究》

杨海娇 魏加华 任倩慧

Abstract：

The Qaidam Basin is a typical arid inland area in China. Recognizing the interaction between surface water (SW) and groundwater (GW), characteristics of water chemistry, and change law along the river in the basin is significant for developing and utilizing regional water resources and ecological protection laws. Hydrochemical and statistical analysis methods were used to study the SW- GW interactions, with the hydrochemical characteristics and differences being analyzed based on field investigation and analysis. According to the controlling effect of geological structure, strata, and landform on the hydraulic connection, the SW-GW interactions are divided into the following types: bedrock barrier + lithology control, lithology control + hydrometeorological influence, and lithology control. The hydrochemical types change from Ca to Na or Mg and from bicarbonate to chloride ion from the mountainous area to the tail area. The changing trends of the hydrochemical influence mechanism along the flow paths gradually change from water-rock interaction to evaporation-precipitation. The transformation of the SW-GW interaction in the inter-mountain valley and front of the alluvial-proluvial fan causes a local reversal of the changing law of hydrochemical characteristics along the river that are influenced by a bedrock barrier and lithology control. This is due to the lithology differences of aquifer, Na+ , Cl− , and SO2 - 4 that are dominant in SW and GW in the south. Ca2+ and HCO− 3 are dominant in the north and east, and the F− concentration in the north is higher compared to other watersheds

 Hits 1202  Downloads 207  Comment