5种沉水植物对重金属富集能力的对比研究

为了探求不同的沉水植物对水体中重金属吸收富集能力的差异,采用原子吸收光谱法,对淮河支流东风渠水体及水体中常见的5种沉水植物:菹草、黑藻、龙须眼子菜、穗花狐尾藻及小茨藻进行了铅(Pb)、镉(Cd)、锌(Zn)、铜(Cu)含量分析。结果表明:5种沉水植物样品中重金属含量远远高于水体重金属背景值,对重金属Cu、Pb、Cd、Zn的富集系数为58~1 515,对Zn富集最强,最大富集量达到242.42 mg/kg,富集系数为1 515。不同的沉水植物对重金属的吸收富集优势存在明显差异,利用沉水植物来修复水体重金属污染时,须依据不同的污染元素来选择合适的沉水植物。

Comparison of Heavy Metal Accumulation by Five Submerged Macrophytes

In this paper, atomic absorption spectrometry was used to analyze the contents of Pb, Cd, Zn and Cu in the waterbody of Dongfeng canal of Huaihe River tributary as well as in such five common submerged macrophytes as Potamogeton crispus L., Hydrilla verticillata, Potamogeton pectinatus L., Myriophyllum spicatum, and Najas minor all grown in the water, aiming at comparison of the differences of submerged macrophytes on heavy metal accumulation. The results showed that the contents of heavy metals in the submerged macrophytes were much higher than the background values. Bioconcentration factor of Cu, Pb, Cd and Zn was 58~1515. Concentration of Zn was maximal. Maximal concentration was 242.42 mg/Kg, and bioconcentration coefficient was up to 1515. Various macrophytes had obvious different accumulation characteristics for different heavy metals. As a result, utilization of submerged macrophytes to remediate water environment polluted by heavy metals must be based on selection of suitable macrophytes according to different pollution elements.