乌伦古河流域潜水组分环境背景值研究

Research on environmental background values of phreatic water components in Ulungu river basin

地下水环境背景值是地下水污染识别、评价以及防治的重要依据。文中依据乌伦古河流域地形地貌、水文地质条件,在潜水环境单元划分的基础上,运用数理统计法和经验法计算得到了各水环境单元的潜水环境背景值,并采用单因子指数法对研究区潜水污染现状进行了评价。结果表明:各水化学组分背景值空间差异较大,Cl^(-)、K^(+)+Na^(+)、Ca^(2+)、Mg^(2+)、TDS和总硬度等组分在不同水环境单元区内的大小表现为冲洪积平原区>山前基岩区>山间河谷区;山前基岩区与冲洪积平原区潜水受人类活动影响严重,山间河谷区受人为影响最弱;流域潜水均受到不同程度污染,山前基岩区污染比例为22.65%,山间河谷区为13.89%,冲洪积平原区为27.81%;数理统计法与经验法相比,对数据的处理更合理,计算结果更能体现研究区潜水环境背景值。

Environment background values of groundwater are the important basis for pollution identification,evaluation and prevention.Based on the topography,geomorphy,hydrogeology and the environment unit division of phreatic water in Ulungu river basin,the environment background values of phreatic water in the different unit were obtained with the mathematical statistics and empirical methods.The single factor index method was used to evaluate the pollution status of phreatic water in the study area.The results showed that the background values in the different unit had obvious spatial differences.Cl^(-),K^(+)+Na^(+),Ca^(2+),Mg^(2+),TDS and total hardness in the phreatic water appeared alluvial plain>piedmont bedrock area>valley area.The phreatic water in piedmont bedrock area and alluvial plain were influenced by human activities seriously,whereas the valley area was influenced a little.Phreatic waters in all units were polluted.The proportions of pollution in piedmont bedrock area,valley and alluvial plain were 22.65%,13.89%,and 27.81%,respectively.Compared with the empirical method,the mathematical statistical method was more reasonable in data processing,and the calculated results can better reflect the background values of phreatic water in the research area.