毕节地区岩溶地下水水化学特征与水质评价

贵州毕节地区岩溶地下水资源丰富。由于母岩碳酸盐岩的特殊地球化学背景,地下水化学特征和水质特殊,为了查明该区地下水资源能否开采作为饮用水资源,开展毕节地区岩溶地下水水化学特征与水质评价研究。根据研究区所取22组水样的水化学测试结果,运用水化学软件AqQA做Piper三线图,分析研究区地下水水化学特征,并对水样进行了舒卡列夫分类。运用单因子评价和模糊综合评价2种方法分别对研究区的岩溶地下水质量进行评价。研究结果表明:①研究区水化学类型主要为HCO₃-Ca·Mg型,主要分布在研究区的西部和南部,且大部分区域碳酸盐硬度>50%;②单因子评价结果显示研究区的地下水质量能够满足饮用水标准的占59.1%;③模糊综合评价的结果表明研究区的地下水质量能够满足饮用水标准的水样点占81.8%。从总体来看,研究区地下水资源可以开采作为饮用水资源。该研究结果为今后在该区开采岩溶地下水资源提供技术指导。

Chemical Characteristics and Water Quality Assessment of Karst Groundwater in Bijie

In Bijie of Guizhou Province which is endowed with abundant karst groundwater resource, the unique geochemical background of parent rock carbonate rock gives rise to the special hydrochemistry and groundwater quality. We investigated the hydrochemical features of karst groundwater in Bijie and assessed the water quality in order to find out whether the karst groundwater in this area can be exploited as drinking water resource. According to hydrochemical test results of 22 groups of water samples collected from the study area, we obtained the Piper plot of groundwater’s chemical features via software AqQA and classified the water samples based on Shoka Lev’s classification. Moreover, we assessed the karst groundwater quality in the study area by using single factor evaluation and fuzzy comprehensive evaluation. Results unveil that the hydrochemical types of the study area are chiefly HCO₃-Ca·Mg, distributing in the west and south parts of the study area, with the hardness of carbonate in most areas greater than 50%. Single factor evaluation demonstrates that standard-meeting groundwater quality in the study area reaches 59.1%, whereas fuzzy comprehensive evaluation suggests that standard-meeting groundwater quality amounts to 81.8%. In general, groundwater resources in the study area can be exploited as drinking water resource. The findings of this study offer technical guidance for the exploitation of karst groundwater resources in this area.