Study on Environmental Factors of Fluorine in Chagan Lake Catchment, Northeast China

Abstract

The Chagan Lake Catchment is located in the midwest of Songnen Plain, which is a typical high fluoride groundwater area. High fluoride water has an important impact on the economic development and ecosystem stability of Chagan Lake. In this study, the spatial distribution characteristics and influencing factors of fluorine in Chagan Lake Catchment are discussed by using hydrochemistry and mathematical statistical analysis. The groundwater in the study area was characterized as Na+-rich and Ca2+-poor, with a high pH value and high HCO3– content. The average concentration of F– was 3.02 mg/L, which was the highest in Qian’an County. The dissolution of fluorine-containing minerals and the desorption of F– in soil provided the source of F– in groundwater, while calcite and dolomite precipitation, cation exchange, and evaporation concentration provided favorable conditions for F– dissolving, migration, and enrichment in water. In addition, the concentration of F– in surface water was 4.56 mg/L, and the highest concentration was found in Hongzi Pool and Hua’ao Pool. The elevated concentrations of F– in both surface water and groundwater in the study were affected by human factors, such as rice planting and water conservancy project construction.