山底河流域重金属污染特征分析

山底河流域地表水体下游存在多处污染源,导致山底河水质变差,水体中多种重金属离子严重超标。为此,以山底河流域地表水体为例,布置了11个点位,自上游至下游分别编号为S1-S2、S3-S4、S5-S11,采用单项污染指数评价法和内梅罗综合污染指数法评价了重金属污染现状,同时采用相关性分析法分析酸性老窑水中重金属特征因子情况。结果表明,地表水重金属含量浓度空间差异性较明显,低等变异(CV≤50%)、中等变异(50%100%)分别占42.9%、14.3%、42.9%,其中Hg、Cd、Mn的超标率超过50%,Mn的超标倍数达千倍,Cd的超标倍数亦近百倍;流域仅2个取样点水环境质量综合污染指数WWQI≤1,水质优良,有4个取样点WWQI在1~10之间,水质较好,其余5个取样点水质差,其中3处水质极差,分别为S6、S7、S9,WWQI分别为388、456、137,数值极高;Zn、Cd、Mn之间具有极强相关性,其污染源为酸性老窑水。

Analysis of Heavy Metal Pollution Characteristics in Shandi River Basin

There are many sources of pollution in the downstream of the surface water body in the Shandi river basin,which results in poor water quality and many heavy metal ions seriously exceed the standard.In this study,water samples were collected in the field 11 points,numbered S1-S2,S3-S4,and S5-S11 from upstream to downstream,were arranged in the basin.Meanwhile,the single pollution index evaluation method and the Nemero comprehensive pollution index method were used to evaluate the status of heavy metal pollution.At the same time,the correlation analysis was adopted to analyze the characteristic factors of heavy metals in acid old kiln water.The results show that the spatial difference of heavy metal content in surface water was obvious.In addition,the low variation(CV ≤50%),the medium variation(50%100%)accounted for 42.9%,14.3%and 42.9%,respectively.Furthemore,the exceed ratio of Hg,Cd and Mn were higher than 50%,and Mn and Cd have large exceed multiple,whose order of magnitudes reached thousand and nearly hundred.In the watershed,there were only 2 sampling points with excellent water quality(WWQI≤1).Another 4 sampling points where WWQI were between 1-10,have better water quality.The poor water quality was exhibited in remaining 5 sampling points,where the worse water quality occurred in 3 points,named S6,S7 and S9,accompanied by extremely high WWQI value(388,456 and 137).The correlation analysis demonstrated that there is strong correlation among Zn,Cd and Mn,source pollution of which is acid old kiln water.