金矿开发中的―采、选、冶‖环节均容易向环境中排放Cd、Pb、Cu、Zn、Cr等重金属元素，造成了水土重金属污染问题。秦岭小峪河金矿区矿业开发频繁，目前已形成采矿废石堆12处、尾矿库7处，为环境地表水、沉积物、土壤、植被带来重金属污染风险。为了研究秦岭小峪河金矿区重金属污染状况，以期为矿山污染环境的恢复治理提供必要依据，通过在小峪河上游、中游、下游采集地表水、沉积物、土壤以及植物样品，室内借助火焰原子吸收分光光度法对样品中的Cu、Pb、Zn、Cd、Cr5种类重金属含量及形态分布特征进行分析，并采用潜在危害生态指数法、单项污染指数法、内梅罗污染综合指数法、污染负荷指数法、地积累指数法等对研究区重金属状况进行了评价。论文初步分析了各类重金属在不同环境介质中的释放、迁移和转化规律，并对矿区重金属污染的环境效应进行了探索。 结果显示：地表水中重金属元素含量之间显著相关且自上游到下游呈累积现象，中、下游地表水重金属污染严重，其中下游Cu、Pb、Cd、Cr分别超标1.14倍、4.46倍、3.30倍、6.83倍，已不适合作为农田灌溉用水；沟道沉积物重金属污染程度依次为下游>中游>上游，且下游污染严重，重金属的迁移顺序为Cd>Pb>Cu>Zn>Cr，主要重金属污染物为Pb、Cd；土壤中各重金属含量总体表现为下游>中游>上游，主要重金属污染物为Cd、Cu、Zn，重金属迁移顺序为Cd>Pb>Cu≈Zn>Cr；重金属元素含量在艾草和碱草中由矿区上游到下游呈累积现象，且污染程度为Pb>Cd>Cr>Cu>Zn，相同植物对不同重金属吸收能力不同，不同植物对相同重金属吸收能力也存在差异。 综上所述，小峪河金矿区沟道地表水、沉积物、土壤、植物等受重金属污染严重，亟需治理与恢复。

ABSTRACT The development of gold mining, separation and smelting can easily take some heavy metals like Cd、Pb、Cu、Zn、Cr into external environment, so it can get some heavy metal pollution in surface water、soil、river sediment and vegetations. The mining activities are frequently in Qingling Xiao’yu river gold field, and now it made 12 piles of waste rocks and 7 tailings, so it takes the pollution risk of heavy metals to surface water、soil、river sediment and vegetations. Based on research of heavy metal pollution in Qinling Xiao’yu gold mining area, necessity for recovering and managing the pollution caused by mining has been provided. By sampling surface water、soil、river sediment and vegetations(Wormwoods and Lyme grass) in Xiao’yu River from upstream to downstream,using flame atomic absorption spectrophotometry analyzed the component and content of Cu、Pb、Zn、Cd、Cr in samples , and by taking the method of potential ecological index 、the single pollution index method and Integrated pollution index method、 geo-accumulation pollution index、The pollution load index evaluate the condition of heavy metal pollution. The paper preliminary analysis of the various metals released, migration and transformation law in different environmental media, and explored the environmental effects of heavy metal pollution in mining area. From the analysis of the samples, we have found that the content of heavy metals in the surface water is significantly correlated with each other and it is badly polluted, which can be found from the upstream to the downstream. The testing results show that the downstream surface water is polluted so serious that its content of Cu, Pb, Cd, and Cr exceeded the standard ratio by 1.143, 4.46, 3.3, and 6.83, which has been made improper for irrigation. The results of our experimental testing and measurement show that the pollution rate is in the order of downstream>middle>upstream, with the downstream more serious polluted, in which the main heavy metal pollutants in the sediment are Pb and Cd. The experimental analysis works out the biological activity coefficient in different heavy metals, which reveal the heavy metal migration follows the order below: Cd>Pb>Cu>Zn>Cr.The sequence of heavy metals content in soil in the mass is downstream>middle>upstream, also the main pollutants are Cd、Cu、Zn. By analyzing the distribution and biological effectiveness in soil, the migration order of heavy metals is Cd>Pb>Cu≈Zn>Cr. Between Wormwoods and Lyme grass, Zn、Pb、Cu have high content and Cr、Cd have less content , as well as metals accumulated from upstream to downstream. The absorbing abilities of the same plant is differs when absorbing different heavy metals, so is different plants absorbing the same metal. Lyme grasses and Wormwoods both have been badly polluted by heavy metals, and the degree of pollutants’ content is Pb>Cd>Cr>Cu>Zn. In conclusion, the surface water、soil、river sediment and vegetations in Xiao’yu gold mining area have been severely polluted, recovery and management of pollution are badly in need.