不同评价方法在地下水源水质评价中的应用——以天津市为例

为明确地下水源水质的空间变化及其主要影响指标，在天津市5个市辖区地下水源设置202个采样点，于2018年枯水期和平水期在各点位采集水样并分析各水质指标，分别采用单因子评价法、主成分分析法和水质指标赋值法等3种评价方法，解析地下水源水质的空间变化并进行排名。结果表明：天津市地下水源主要指标有9项超标，分别为氟化物、pH、钠、菌落总数、色、氯化物、耗氧量、硝酸盐氮和硫酸盐，且多数指标受地质因素影响。不同评价方法对地下水源水质评价结果略有不同，总体而言，宁河区和蓟州区地下水源水质相对较好，武清区、北辰区和静海区水质相对较差。研究表明，采用水质指标赋值法的评价结果具有问题导向性，更能反映农村地下水源实际情况。同时，地质因素对地下水源的影响不可避免，结合当前乡镇级水源管理工作，针对水源水质特点，建议安装净水工艺设施以提升饮用水安全保障水平。

Application of different methods for quality evaluation of groundwater drinking water sources: A case study of Tianjin

In order to determine the spatial variation and main influencing factors of groundwater drinking water quality, a total of 202 sampling sites were studied across all the groundwater drinking water sources in five districts of Tianjin. Water samples were collected at each sampling site during the low water period and high water period in 2018, and water quality parameters were analyzed. Single factor assessment, principal component analysis, and water quality index valuation were used to identify the spatial variation and assess the water quality. The results of different evaluation methods for groundwater drinking water quality were slightly different. There were some differences among the regions in Tianjin. Overall, the water quality of rural groundwater drinking water sources in the Ninghe District and Jizhou District was better than that in Wuqing District, Beichen District, and Jinghai District. There were nine main indicators of groundwater quality in Tianjin, namely fluoride, pH, sodium, bacterial count, chroma, chlorine, oxygen consumption, nitrate nitrogen, and sulfate, and most were affected by geological factors. The results of the water quality index valuation could better reflect the actual situation of rural groundwater drinking water quality. The influence of geological factors on groundwater was inevitable. Combined with the current management of township-level drinking water sources and the characteristics of water quality, the safety of drinking water should be improved through the installation of water purification facilities.