Comparison of surface water chemistry and weathering effects of two lake basins in the Changtang Nature Reserve, China
Rui Wang
,
Zhaofei Liu
,
Liguang Jiang
,
Zhijun Yao
,
Junbo Wang
,
Jianting Ju
DOI:10.1016/j.jes.2015.03.016
Received February 27, 2015,Revised January 01, 1900, Accepted March 02, 2015, Available online June 13, 2015
Volume 28,2016,Pages 183-194
The geochemistry of natural waters in the Changtang Nature Reserve, northern Tibet, can help us understand the geology of catchments, and provide additional insight in surface processes that influence water chemistry such as rock weathering on the Qinghai–Tibet Plateau. However, severe natural conditions are responsible for a lack of scientific data for this area. This study represents the first investigation of the chemical composition of surface waters and weathering effects in two lake basins in the reserve (Lake Dogaicoring Qiangco and Lake Longwei Co). The results indicate that total dissolved solids (TDS) in the two lakes are significantly higher than in other gauged lakes on the Qinghai–Tibet Plateau, reaching 20–40 g/L, and that TDS of the tectonic lake (Lake Dogaicoring Qiangco) is significantly higher than that of the barrier lake (Lake Longwei Co). Na+ and Cl− are the dominant ions in the lake waters as well as in the glacier-fed lake inflows, with chemical compositions mainly affected by halite weathering. In contrast, ion contents of inflowing rivers fed by nearby runoff are lower and concentrations of dominant ions are not significant. Evaporite, silicate, and carbonate weathering has relatively equal effects on these rivers. Due to their limited scope, small streams near the lakes are less affected by carbonate than by silicate weathering.
