平原区承压水上部弱透水层对NH_(4)^(+)、NO_(3)^(-)的阻滞能力分析研究——以北京市通州区为例

Quantitative simulation of retardation effect of NH_(4)^(+) and NO_(3)^(-)by aquitard layer on confined water in plain:a case study of Tongzhou district in Beijing

由于工农业经济快速发展引起的广大平原区浅部地下水不同程度污染已经成为比较普遍的问题。平原区深部的承压水因水质较好,往往成为当地供水的主要水源,因此其地下水保护至关重要。承压含水层上部的弱透水层在阻滞浅部污染物进入承压含水层的过程中起到极其关键的作用。本次研究,以华北平原典型区域通州区为例,以研究区水文地质单元为基础,结合钻孔资料获取的地层结构特征、岩性特征等,开展了潜水与承压水之间弱透水层对污染物阻滞能力的探索模拟研究,评价结果显示研究区弱透水层污染物阻滞能力西北部最差,自西北向东南呈现出先增强后减弱的态势。本次研究的思路和方法可为同类平原区弱透水层对污染物阻滞作用研究提供借鉴。

Due to the rapid development of industrial and agricultural economy,the shallow groundwater pollution has become a common problem.The confined water in the deep plain is the main source of local water supply because of its good quality.The weak permeable layer above the confined aquifer plays an important role in preventing the shallow pollutants from entering the confined aquifer.In this study,Taking Tongzhou area,which located in Huabei plain of China,as an example,based on the hydrogeological unit of the study area,and combined with the water quality characteristics of phreatic water and lithologic character,fifteen kinds of simulation schemes were developed to quantitative evaluation of the retardation effect of the aquitard layer between the groundwater.The research ideas and methods can be used for reference in evaluating the vulnerability of confined water in other similar plain areas.