鲁西南黄河冲积平原浅层地下水的环境背景值

Background Value of Shallow Groundwater Environment of the Yellow River Alluvial Plain in the Southwest of Shandong Province

为构建鲁西南地区浅层地下水环境预警监测体系,以鲁西南黄河冲积平原2008年—2015年地下水专项调查及例行监测174个点位、14项指标的监测数据为依据,首次在综合分析其地形地貌、水文地质、径流特征等基础上,进行地下水环境单元分区,并采用数理统计的方法研究了不同环境单元浅层地下水环境背景特征值,对不同指标背景值进行了比较,对溶解性总固体(TDS)、F-、I-的成因进行了分析。结果表明:地下水化学组分浓度与地下水环境单元,特别是地下水动力学特征、沉积环境等密切相关。冲湖积平原区的Na^(+)、TDS、总硬度、SO^(2-)_(4)、Cl-、F-、I-,以及冲洪积平原区的F-、I-、总硬度均具有原生劣质性,其集中值均超过《地下水质量标准》(GB/T 14848—2017)Ⅲ类标准。以背景值域下限对该区地下水质量进行评价,结果显示该区地下水处于较差水平。此结果可为该地区今后进行地下水污染状况分析、评价提供理论支撑。

To construct early warning and monitoring system of shallow groundwater environment in the southwest of Shandong Province,relatively detailed groundwater environment subregions were divided in Yellow River alluvial plain in the southwest of Shandong Province on the basis of the analysis of regional topography,hydrogeology and groundwater runoff.The groundwater environment background values of 14 indices were established for the first time by collecting groundwater hydrochemical data of 174 monitoring points,which originated from special and routine monitoring from 2008 to 2015.The background values of different indices were analyzed and compared,and the physical causes of TDS,F-,and I-were explained.The results showed that the concentrations of chemical ingredients in groundwater were in close relationship with subregions,dynamic and depositional characteristics of groundwater.The native inferiority was considered to exist in the indices of Na^(+)、TDS、total hardness、SO^(2-)_(4)、Cl-、F-、I-of alluvial lacustrine plain and F-、I-、total hardness of alluvial proluvial plain,with their background values exceeding the threshold limit of classⅢof Standard for Groundwater Quality(GB/T 14848—2017).The groundwater quality of researched area,based on the lower limit of background range,was evaluated as a poor level.The results provide scientific basis for reasonable evaluation and analysis of local groundwater pollution in the future.