Water chemistry and source analysis of major ions of Bangong Lake in Tibetan Plateau

Abstract

Bangong Lake,was an inland lake on the Tibetan Plateau, which was an international lake across China and India. The water chemistry characteristics were analyzed by testing the chemical composition of the lake water in Bangong Lake. The Gibbs diagram was used to explore the main controlling factors of lake water, and the main ion source of lake water was described in combination with the proportion of dissolved ions. The results showed that the center was brackish water and the east was fresh water of the Bangong Lake with a weak alkaline water. From the surface to the bottom, the temperature, dissolved oxygen and redox potential were decreasing, while the conductivity was increasing. The main cation of lake water was Na+, the main anion was Cl-, and the main chemical type was SO4-Cl-Na. The soluble ions in the central water were mainly controlled by evaporation and concentration, while the soluble ions in the eastern water were mainly controlled by rock weathering. The cations in the water were mainly derived from the silicate rock weathering and the dissolution of evaporite, and the anions was mainly derived from the dissolution of evaporite.