Wei Shuhe, Zhou Qixing, Saha Uttam Kumar, Xiao Hong, Hu Yahu, Ren Liping, Ping Gu
Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China.
J Hazard Mater. 2009 Apr 15;163(1):32-5. doi: 10.1016/j.jhazmat.2008.06.062. Epub 2008 Jun 25.
One of key steps of phytoremediating heavy metal contaminated soils is still the identification of hyperaccumulator and accumulator. In a former published article, Conyza canadensis L. Cronq. expressed some basic properties of Cd-hyperaccumulators. In this study, concentration gradient experiment and two sample-analyzing experiments were used to identify whether this plant is a Cd-hyperaccumulator. When grown on soil spiked with Cd at the rate of 10 and 25 mg kg(-1) in concentration gradient experiment, C. canadensis had both Cd enrichment factor (EF) and Cd translocation factor (TF) greater than 1, while the shoot biomass did not differ significantly as compared to the control. On the other hand, with Cd-spiking rates of 10 and 25 mg kg(-1), the Cd concentration in the shoot did not exceed 100 mg kg(-1), which is considered as the minimum shoot Cd concentration to qualify as a hyperaccumulator. In the sample-analysis experiments from a Pb-Zn mine area and wastewater irrigation region, C. canadensis also showed Cd-accumulator characteristics. Based on the results accomplished, we propose C. canadensis as a Cd-accumulator.
植物修复重金属污染土壤的关键步骤之一仍然是超富集植物和富集植物的鉴定。在之前发表的一篇文章中，小飞蓬表现出了镉超富集植物的一些基本特性。在本研究中，采用浓度梯度试验和两个样品分析试验来鉴定该植物是否为镉超富集植物。在浓度梯度试验中，当小飞蓬生长在添加了浓度为10和25 mg kg(-1)镉的土壤上时，其镉富集系数（EF）和镉转运系数（TF）均大于1，而地上部生物量与对照相比无显著差异。另一方面，在镉添加量为10和25 mg kg(-1)时，地上部镉浓度未超过100 mg kg(-1)，而这一浓度被认为是作为超富集植物的地上部镉浓度最小值。在来自铅锌矿区和污水灌溉区的样品分析试验中，小飞蓬也表现出镉富集植物的特征。基于所取得的结果，我们提出小飞蓬为镉富集植物。
