[Hydrochemical Characteristics and Sources of Qingshuijiang River Basin at Wet Season in Guizhou Province].

According to the ion content and chemical characteristic analysis of Qingshuijiang River water during wet season, the result shows that the chemical composition of the river water is dominated by Ca2+, HCO(3-); Mg2+, and SO4(2-). The TDS concentration (213.96 mg · L(-1)) is significantly higher than the average value of rivers worldwide. Seawater correction approach (Cl(-) normalized seawater ratios) was applied to estimate the contribution proportions of local precipitation to the solutes, and it is found that the contribution ratio of precipitation (2.23%) is lower than the average value (3%) of global catchments. Furthermore, Gibbs graph combining major ion element ratio analysis indicates that the catchment hydrochemistry is mainly originated from carbonate rock weathering, which becomes increasingly distinct as the river goes downstream. Both carbonic acid and sulfuric acid play crucial roles in the chemical weathering. Ion source analysis demonstrates that Ca2+, Mg2+, HCO3- are mainly derived from chemical weathering of carbonate mineral (Dolomite and Calcite); Na+, K+ and Cl- are primarily contributed by silicate mineral weathering; SO4(2-) and NO3- stemmed are mainly from acid atmospheric deposition and from urban sewage input. Anthropogenic analysis suggests that the chemical composition of Qingshuijiang River is greatly impacted by the upriver industrial and mining enterprises activities.