青藏高原东北部更尕海流域水化学特征及控制因素研究

he analysis of water chemistry in the Genggahai Lake in the northeast Tibetan plateau and its inflowing spring water shows that HCO3--Ca2+-(Na++K+) are the dominant ions of the inflowing spring water, while Cl--Na+ are the dominant ions of the lake water. Attributed to the large watershed area of the Genggahai Lake, the seasonal varieties in the dominant ions of inflowing spring water are stable. On the yearly time scale, variations in Cl- of the inflowing spring water may mainly controlled by evaporation-crystallization effect, while Na+ and Ca2+ are affected by rock weathering function. Besides, the yearly fluctuations of HCO3- are influenced by water table, which is related to regional evaporation and precipitation. In addition, on the seasonal time scale, because of enhanced evaporation, contents of Cl- and Na+ increased obviously in the Genggahai Lake during July; owing to the intense photosynthesis of the aquatic plants, HCO3- and Ca2+ contents decreased. On the yearly time scale, the concentrations of Cl- and Na+ in lake water are influenced by the contents of corresponding ions of inflowing spring water; while contents of HCO3- and Ca2+ are impacted by both of the inflowing water and the intense photosynthesis in the lake.