八种水生植物对重金属富集能力的比较研究

通过野外采样和系统分析方法,研究了芜湖市四褐山工业区附近水域中Cu、Pb、Cd、Zn和Mn5种重金属的含量及其在8种水生植物体内的积累特性。结果表明,工业区水体污染严重,重金属含量严重超标,分别为标准值的9、10.1、400、3和438倍;8种水生植物的重金属积累量均较大,其中以水鳖根、茎叶的Cu、Pb、Cd、Zn含量最高,分别为水体中重金属浓度的9.12和2.59倍、33.41和5倍、0.8和0.3倍、26.9和9.1倍,明显高于其它7种水生植物;8种水生植物不同器官对Cu、Pb、Zn的富集系数均>1,富集能力较强。其中,香蒲对Pb、Cd的吸收能力表现为茎叶>根。结果表明,在Cu、Pb和Zn等重金属复合污染水域的植物治理中,浮萍、香蒲、水鳖、中华慈姑、芦苇、空心莲子草等植物有着较大的发展潜力和应用前景。

Heavy metals accumulation by hydrophytes

With field sampling method,we measured the concentrations of Cu,Pb,Cd,Zn,and Mn in the waters around Siheshan industrial area of Wuhu,and compared the accumulation characteristics of these heavy metals in 8 species of hydrophytes grown there.The results showed that in the test waters,the concentrations of Cu,Pb,Cd,Zn,and Mn were 9,10.1,400,3,and 438 times higher than the standards,respectively,and all of the test hydrophytes could accumulate larger amounts of the metals.Hydrocharis dubia had the highest accumulation capability,with the concentrations of Cu,Pb,Cd and Zn being 9.12,33.41,0.8 and 26.9 times higher in its root,and 2.59,5,0.3 and 9.1 times higher in its stem and leaf than in the waters,respectively.The bioaccumulation coefficients of Cu,Pb and Zn in different organs of test plants were all larger than 1.For Typha orientalis,its root had a higher capability of accumulating Pb and Cd than its stem and leaf.Lemna minor,Typha orientalis,H.dubia,Sagittaria trifolia,Phragmites australis and Gynura crepidioides had the greater development potential and application prospect in the phyto-remediation of the waters contaminated by heavy metals such as Cu,Pb and Zn.