Analysis Of Water Chemistry Characteristics And Impact Study Of Duliujiang River Basin In Guizhou Province

Study on water chemistry and influencing factors for the Duliu River,it's conducive to the protection of water resources.In this study,62 water samples were collected in January and July in 2015,respectively.The T?pH?EC?DO?Na⁺?K⁺?Ca²⁺?Mg²⁺?Cl-?NO₃^-?SO₄^2-?HCO₃^-?SiO₂ and nutritional elements?TP?NH₃-N?were determined.According to the Gibbs diagram,triangle diagrams and correlation analysis,studied the characteristics of water chemistry,temporal and spatial distribution of the Duliu River basin and the main ion controlling factors of the river water.It showed that the water was alkaline,the dominant cations and anions were Ca²⁺?Mg²⁺?HCO₃^-? SO₄^2-,respectively.The water chemical type was HCO₃^-—Ca²⁺—Mg²⁺.The water chemistry was mainly controlled by the weathering of rocks.Characteristics of water chemistry was obvious seasonal changes,which is the result of the combined effect of seasonal rainfall and evaporation.The concentration of major ions decreased gradually in the mainstream of the Duliu River basin,which was related to the geological background and human activities.The Duliu River basin was mainly controlled by carbonate weathering and silicate weathering.Based on the forward model,the rock weathering process and the carbon sink effect was studied after the rainfall input and the degree of human activities were corrected,the relative contribution of each factor to the main ion composition of the river was estimated:carbonate weathering> silicate weathering> atmospheric input> human activities.The rock weathering rate of the Duliu River basin was 22.54t/?km2·a?,and the CO₂ consumption of rock weathering was about 241.27 × 103 mol/?km2·a?,both closed to the world average(rock weathering rate(246 × 103 mol/?km2·a?,indicating the important role of weathering in the small watershed on the global carbon cycleUpper Duliu River basin was mainly affected by industrial activities,and the downstream area was affected by the complicated human activities.The relationship between land use structure and water chemistry and water quality in the Duliu River basin was analysed.The proportion of land use types in the Liujiang River basin was forest land> cultivated land> shrub> unused land> construction land> water body,forest land occupies the main position.The land use was positively correlated with nutrient elements and had a negative effect on the water environment.Forest land was negatively related to nutrient elements and had a positive effect on the environment.The rational allocation of land use was conducive to the protection of river basin water environment.