玛纳斯河流域地表水重金属分布特征及风险评价

Distribution characteristics and risk assessment of heavy metals in surface water of the Manas river basin

为了解玛纳斯河流域地表水重金属特征,本文选取Zn,As,Cr,Cu,Ni,Pb,Cd,Hg 8种重金属元素,通过单因子污染指数、内梅罗综合污染指数和水体健康风险评价模型等方法评估了水体中重金属的污染状况、潜在风险及可能的来源。结果表明,研究区内的重金属含量水平大小顺序为:Zn>As>Cr>Cu>Ni>Pb>Cd>Hg,整个玛河流域重金属污染水平低。致癌重金属Cr,As,Cd是玛河流域水体污染的主要污染物。玛河流域水体中Cd,Ni,Cu,Cr,Pb,Zn污染来源于流域内盛行的养殖、农业、工业产业的人为污染源;As的污染来源于成土母质自然污染源。

To better understand the characteristics of heavy metals in the surface water of the Manas river basin,eight heavy metal elements,i.e.,Zn,As,Cr,Cu,Ni,Pb,Cd and Hg,were analyzed.These elements were subjected to various water health risk assessment models and methods,including the single-factor pollution index and the Nemerow comprehensive pollution index which help assess the pollution status,potential risks and possible sources of heavy metals in water bodies.Results revealed that the level of heavy metal content in the study area followed the order Zn>As>Cr>Cu>Ni>Pb>Cd>Hg.Moreover,the heavy metal pollution level in the entire Manas river basin was observed to be low,and the carcinogenic heavy metals Cr,As and Cd were the main water pollutants in the basin.The pollution of Cd,Ni,Cu,Cr,Pb and Zn in the Manas river basin was attributed to human sources in aquaculture,agriculture and industrial industries,which were prevalent in the basin.Further,the pollution of As was attributed to the natural sources of soil-forming parent materials.