Maine M A, Duarte M V, Suñé N L
Consejo Nacional de lnvestigaciones Científicas y Técnicas, Argentina.
Water Res. 2001 Aug;35(11):2629-34. doi: 10.1016/s0043-1354(00)00557-1.
Cd uptake capacity of a group of floating macrophytes (Salvinia herzogii, Pistia stratiotes, Hydromistia stolonifera and Eichhornia crassipes) was determined in outdoors experiments during the lowest temperature period of the year. Although all studied species were highly efficient in the Cd uptake, Pistia stratiotes was selected for further research because of its superior performance and its higher average relative growth rate. Cadmium% removal by Pistia stratiotes was greater in the first 24 h of the experiments (63, 65, 72 and 74% of the added Cd for 1, 2, 4 and 6 mg Cd 1(-1), respectively). After 31 days of growth, Pistia statiotes efficiently removed Cd at the studied concentrations. The macrophyte was able to keep its capacity for Cd removal even though some toxicity symptoms appeared at 4 and 6 mg Cd 1(-1). The greater the initial concentration, the greater Cd bioaccumulation rates. The increase of Cd concentration in plant tissues occurred especially in roots and was linearly related to the quantity of Cd added. Cd sorption by roots is faster than translocation to the plant aerial part and it occurs mainly during the first 24h.
在一年中温度最低的时期进行的户外实验中，测定了一组漂浮大型植物（赫氏槐叶萍、大薸、匍匐水蕹和凤眼莲）对镉的吸收能力。尽管所有研究的物种对镉的吸收效率都很高，但由于大薸表现优异且平均相对生长率较高，因此被选作进一步研究对象。在实验的最初24小时内，大薸对镉的去除率更高（对于1、2、4和6毫克/升的镉添加量，分别去除了添加镉的63%、65%、72%和74%）。生长31天后，大薸在研究浓度下有效地去除了镉。即使在4和6毫克/升的镉浓度下出现了一些毒性症状，该大型植物仍能保持其去除镉的能力。初始浓度越高，镉的生物积累率越高。植物组织中镉浓度的增加尤其发生在根部，并且与添加的镉量呈线性相关。根部对镉的吸附比向植物地上部分的转运更快，且主要发生在最初的24小时内。
