Li Jun, Zou Sheng-Zhang, Zhao Yi, Zhao Rui-Ke, Dang Zhi-Wen, Pan Min-Qiang, Zhu Dan-Ni, Zhou Chang-Song
Key Laboratory of Karst Dynamics, Ministry of Natural Resources/Guangxi, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004, China.
Hebei Key Laboratory of Water Quality Engineering and Comprehensive Utilization of Water Resources, Hebei University of Architecture, Zhangjiakou 075000, China.
Huan Jing Ke Xue. 2021 Apr 8;42(4):1750-1760. doi: 10.13227/j.hjkx.202009027.
To investigate the major ionic chemical characteristics and seasonal variations, 27 groundwater samples were collected from the wet season, flat season, and dry season during 2018-2019 in the Huixian Karst wetland, which is the largest low-altitude karst wetland in China. The single pollution standard index was applied to evaluate the groundwater pollution during different periods, and the major ionic factors of the karst groundwater were analyzed using the statistical analysis method, Gibbs diagram, and ion ratio. The results revealed that the groundwater samples were a weakly alkaline fresh water that were rich in Ca and HCO. The average concentrations of the primary ions followed the order of flat season > wet season > dry season; meanwhile, the water quality in the dry season was better than that in the wet and flat seasons. The K and NO in the karst groundwater were mostly affected by the spatial distributions of the aquifers, and the Mg, SO, NO, NH, and TDS were related to the space-season scale. Na, Ca, HCO, and Cl were relatively stable ions in the karst groundwater. The hydrochemical characteristics were primarily determined by carbonate rock dissolution and were found to be the HCO-Ca type, which accounted for 77.78%, 77.78%, and 88.89% in the wet season, flat season, and dry season, respectively. The karst groundwater was predominantly polluted by SO, NO, and NO; particularly, NO exhibited serious pollution points, and SO had heavy pollution points in the wet and flat seasons. The chemical composition of the karst groundwater was controlled mostly by water-rock interactions. Ca and HCO primarily came from calcite dissolution, and the high concentrations of Mg and SO in a few number of points were controlled by dolomite, dolomitic limestone, and pyrite. K, Na, SO, NO, and Cl partly came from atmospheric precipitation, and Na and Cl partly came from human activities; K was related to potash fertilizer, and the main source of NO was chemical fertilizer.
为研究主要离子化学特征及季节变化，于2018 - 2019年期间，在我国最大的低海拔岩溶湿地——辉县岩溶湿地，采集了雨季、平季和旱季的27份地下水样本。采用单污染标准指数法评价不同时期的地下水污染情况，并运用统计分析方法、吉布斯图和离子比值法分析岩溶地下水的主要离子因素。结果表明，地下水样本为弱碱性淡水，富含Ca和HCO。主要离子的平均浓度顺序为平季＞雨季＞旱季；同时，旱季水质优于雨季和平季。岩溶地下水中的K和NO主要受含水层空间分布影响，Mg、SO、NO、NH和TDS与空间 - 季节尺度相关。Na、Ca、HCO和Cl是岩溶地下水中相对稳定的离子。水化学特征主要由碳酸盐岩溶解作用决定，为HCO - Ca型，在雨季、平季和旱季分别占77.78%、77.78%和88.89%。岩溶地下水主要受SO、NO和NO污染；特别是NO存在严重污染点，SO在雨季和平季有重度污染点。岩溶地下水的化学成分主要受水 - 岩相互作用控制。Ca和HCO主要来自方解石溶解，少数点位Mg和SO的高浓度受白云石、白云质灰岩和黄铁矿控制。K、Na、SO、NO和Cl部分来自大气降水，Na和Cl部分来自人类活动；K与钾肥有关，NO的主要来源是化肥。
