【摘要】 以崇左响水地区为研究区域,于2016年丰水期、枯水期、平水期在研究区内采集210个地下水样品并测定,分析岩溶地下水的主要离子化学特征和季节变化,运用多元统计分析法研究地下水主要离子的控制因素.结果表明,研究区岩溶地下水为弱碱性淡水,优势离子均为Ca²⁺、HCO₃^-为主,分别占全部阳离子和阴离子的75%、70%以上,K⁺、Na⁺、Cl^-和NO₃^-平均质量浓度表现为丰水期>平水期>枯水期,Ca²⁺、Mg²⁺、HCO₃^-、SO₄^2-、p H值、TDS、TZ+和TZ-未出现明显的季节性变化.受碳酸盐岩地层的控制,地下水化学类型以HCO₃^-Ca型为主,丰水期和平水期少部分水点为HCO₃·Cl-Ca和HCO₃·SO₄-Ca型水,平水期出现Cl·NO₃-Ca型水,枯水期可见HCO₃^-Ca·Mg型水,反映出少部分水点受地层中白云岩和铁质泥岩溶解、人类源NO₃^-和Cl^-的影响.地下水中Ca²⁺、HCO₃^-主要来源于碳酸盐岩灰岩的溶解,Na⁺、Cl^-、K⁺、NO₃^-来源于大气输入与人为活动的贡献,Mg²⁺、SO₄^2-来源于地层中白云岩、铁质泥岩溶解.地下水化学成分主要受水岩相互作用的控制,碳酸盐岩含水层中的地下水主要受碳酸盐岩溶解因子控制,村庄和人口密集区的地下水主要受大气输入与人为活动因子控制.更多还原

【Abstract】 To investigate the major ionic characteristics,seasonal variation,and controlling factors of karst groundwater at Xiangshui,Chongzuo,210 groundwater samples were collected and measured in wet season,dry season,and flat season in 2016. The controlling factors of karst groundwater were analyzed by using multivariate statistical analysis method. The results showed that the groundwater samples were weakly alkaline fresh water and rich in Ca²⁺and HCO₃^-,which accounted for more than 75% and 70% of total ion concentration. The average concentrations of K+,Na+,Cl-,and NO₃^-decreased in the order of wet season > flat season > dry season. None of the concentrations of Ca²⁺,Mg²⁺,HCO₃^-,SO₄^2-,p H,TDS,TZ⁺,and TZ^- showed significant seasonal variation.The hydrochemical characteristics were found to be of HCO₃^-Ca type and mainly determined by carbonate rock dissolution. Only a small proportion of them were of HCO₃·Cl-Ca and HCO₃·SO₄- Ca type in wet season and flat season,Cl·NO₃^-Ca type appeared in flat season,and HCO₃^-Ca·Mg type appeared in dry season,reflecting the influence of dolomite and ferric mudstone dissolution in the stratum,and of NO₃^-and Cl-input from anthropogenic activities. Groundwater Ca²⁺and HCO₃^-mainly came from limestone dissolution; Na⁺,Cl^-,K⁺,and NO₃^-came from atmospheric precipitation and human activities; while Mg²⁺and SO₄^2-came from dolomite and ferric mudstone dissolution. The chemical composition of groundwater was controlled by water-rock interaction,the groundwater in the carbonate aquifer was controlled by carbonate rocks dissolution,and the groundwater in villages and densely populated areas was affected by atmospheric precipitation and human activity.更多还原