摘要
为研究然乌湖流域地表水水化学特征及离子来源,在然乌湖流域采集了地表水样品和雨水样品,综合利用相关性分析、Piper三线图和Gibbs模型等方法,分析了该区地表水主要离子特征及其控制因素,揭示了该区地表水水中的主要物质来源.结果表明,然乌湖流域地表水pH为7.54~8.48,呈弱碱性,并具有较低的溶解性总固体(59.89~96.75 mg·L^-1),阳离子主要以Ca^2+和Mg^2+为主,Ca^2+当量浓度占阳离子总量的63.3%~76.2%,均值为67.2%,Mg^2+当量浓度占阳离子总量的23.4%~36.2%,均值为31.4%,Ca^2+和Mg^2+约占阳离子总量的98.5%.阴离子以HCO^-3为主,HCO^-3占阴离子总量的74.31%~84.29%,均值为78.21%,SO42-占阴离子总量的9.59%~19.37%,二者约占阴离子总量的93.55%.水化学类型为HCO3^-Ca和HCO3^-Ca·Mg型,水文地球化学过程受人类活动影响较弱,主要受岩石风化作用控制,主要离子来源于碳酸盐岩及硅酸盐岩的风化溶解.
To study the chemistry of surface water and potential control measures in the Ranwu Lake basin,19 samples were collected from Ranwu Lake in 2019.Conventional hydrochemical techniques and statistical analysis methods(descriptive statistics,the Gibbs figure,ion ratio,Piper triangular diagrams)were applied to better understand the solute geochemistry and surface water hydrochemistry in the Ranwu Lake catchment.Surface water in the Ranwu catchment is slightly alkaline(pH of the samples ranged from 7.54 to 8.48 with an average value of 8.06).The concentrations of total dissolved solids(TDS)in the water range from 59.89 to 96.75 mg·L^-1with an average of 79.98 mg·L^-1,the total dissolved solids of all samples are less than 100 mg·L^-1 and belong to fresh water.The TDS are dominated by Ca^2+,Mg^2+,HCO^-3,and SO42-in the Ranwu Lake.The ion concentrations in the lake water samples are in the order of Ca^2+>Mg^2+>Na^+>K^+.The concentrations of Na^+and K^+are very low.Ranging from 0.5 to 1.21 mg·L^-1,with an average value of 0.58 mg·L^-1,the equivalent concentration of Ca^2+accounts for 63.3%to 76.2%of total cations with an average value of 67.2%.The equivalent concentration of Mg^2+accounts for 23.4%to 36.2%of total cations with an average value of 31.4%.Ca^2+and Mg^2+account for 98.5%of total cations.The main anions were HCO^-3 and SO42-.The equivalent concentration of HCO^-3accounts for 74.31%to 84.29%of total anions with an average value of 78.21%.The equivalent concentration of SO42-accounts for 9.59%to 19.37%of total anions with an average value of 15.34%.HCO^-3 and SO42-together account for 93.55%of total anions on average.All the water samples fall in the water-rock interaction field,which suggests that the weathering of rocks primarily controls the major ion chemistry of groundwater in this area.Solutes are mainly derived from carbonate weathering and silicate weathering.The role of cation exchange in the geochemical process of the lake and the influence of human activities on the lake are found to be weak.
作者
张涛
王明国
张智印
刘廷
何锦
ZHANG Tao;WANG Ming-guo;ZHANG Zhi-yin;LIU Ting;HE Jin(Center for Hydrogeology and Environmental Geology,China Geological Survey,Baoding 071051,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2020年第9期4003-4010,共8页
Environmental Science
基金
地质调查项目(DD20190534)。
关键词
水化学
离子来源
元素比值
化学风化
然乌湖
hydrochemistry
ion source
element rations
chemical weathering
Ranwu Lake
