沂河流域地下水水化学特征及水质评价

Hydrochemical characteristics and water quality evaluation of groundwater in the west of Yi River Basin

为了解沂河流域地下水水化学特征、水质以及硝酸盐对人体产生的潜在健康危害风险,选取2017年枯、丰水期采集的156个地下水水样,运用数理统计、Piper三线图、舒卡列夫分类、Gibbs模型和离子比值等方法,分析了沂河流域地下水的主离子特征及其形成机制,分别运用模糊评价和健康风险评价模型对地下水水质和硝酸盐污染产生的健康风险进行了评估.结果表明,研究区枯、丰水期主要阳离子为Ca^(2+),主要优势阴离子为;按TDS划分,均属于淡水和微咸水;水化学类型在空间上变化较大,出现了11种类型,以HCO_(3)·SO_(4)-Ca型为主;水化学组分主要受碳酸盐岩的风化溶解控制.研究区地下水水质较差,主要为Ⅳ类水,枯、丰水期分别占51.2%和41.0%.健康风险评估结果表明,研究区枯、丰水期对成人的健康风险均值分别为1.41和1.47,儿童为2.62和2.75,硝酸盐健康风险较高,长期饮用该地区的地下水对人们的身体健康存在潜在威胁,应引起高度重视.

In order to understand the chemical characteristics of groundwater in the Yihe River Basin, the water quality, and the potential health risks of nitrate to humans, 156 groundwater samples collected in the dry and abundant seasons of 2017 were selected, and mathematical statistics, Piper three-line diagrams, and Shukarev were used. Classification, Gibbs model, and ion ratio methods are used to analyze the main ion characteristics of groundwater in the Yihe River Basin and its formation mechanism. Fuzzy evaluation and health risk assessment models are used to evaluate the health risks of groundwater quality and nitrate pollution. The results show that the main cation in the dry and high seasons of the study area is Ca^(2+), and the main dominant anion is. According to TDS, they belong to fresh water and brackish water. The water chemistry types vary greatly in space, with 11 types appearing. HCO_(3)·SO_(4)-Ca type is the main type;the water chemical composition is mainly controlled by the weathering and dissolution of carbonate rocks. The quality of groundwater in the study area is poor, mainly Grade IV water, with dry and high water periods accounting for 51.2% and 41.0% respectively. The health risk assessment results show that the study area is dry and abundant.The average health risks to adults are 1.41 and 1.47, respectively, and children are 2.62 and 2.75.Nitrate has a higher health risk. Long-term drinking of groundwater in this area poses a potential threat to people’s health and should be taken seriously.