Cr(Ⅵ)、Ni耐性植物筛选及其吸收富集特性研究

Selection of tolerant plants of Cr(Ⅵ) and Ni and the characteristics of bioaccumulation of the plant

采用营养液培养法和二因素完全实验设计,在5 mg.L-1Cr(Ⅵ)、Ni复合污染条件下对22种植物进行筛选实验,选取富集量较高且生长较快的旱伞草Cyperus alternifolius,分析其对Cr(Ⅵ)、Ni的累积规律及生理生化效应。结果表明:(1)在Cr(Ⅵ)、Ni复合污染胁迫下,旱伞草生长状况良好,对铬、镍具有较高的富集能力;(2)在Cr(Ⅵ)、Ni复合污染下,Cr(Ⅵ)抑制旱伞草对Ni的吸收,Ni促进旱伞草对Cr的吸收;(3)分别在单因素Cr(Ⅵ)、Ni的胁迫下,SOD和CAT活性随着Cr(Ⅵ)、Ni质量浓度(0～50 mg.L-1)的增加都是先上升后下降,MDA总体都呈增加的趋势;(4)在Cr(Ⅵ)胁迫下,旱伞草地上部富集总铬的含量较高,但六价铬含量较低,对Cr(Ⅵ)的转化率最大可达到97.00%。研究表明,旱伞草是一种修复Cr(Ⅵ)、Ni污染很有潜力的物种。

By the solution culture method and the completely randomized design involving two factors. The experiment was conducted to select Cyperus alternifolius with fast growing and highly enrichment of heavy metals among twenty-two plants pollutioned with 5 mg/L concentration of Cr （VI）-Ni composite solution and to evaluate it＇s rule of accumulating Cr and Ni and the biological and biochemical functions. The results showed that： （1） The C. alternifolius had a good growth, and a high ability to accumulate the Cr （VI） and Ni. （2） Cr （VI） have a inhibition effection on the absorption of Ni by C. alternifolius, but Ni promoted the accumulation of Cr in C. alternifolius. （3）With the increase of Cr （VI） and Ni concentration（0 - 50 mg/L）, the activity of SOD and CAT in the C. alternifolius firstly increased and then reduced. The MDA content in the C. alternifolius increased slowly at first and then rised sharply with the increase of Cr （VI）, while it was decreased at first and then increased sharply with the increase of Ni concentration. （4） In Cr （VI） stress, the C. alternifolius at above-ground is high in accumulating the total chromium, but is low in accumulating Cr （VI）. The maximum conversion rate of Cr （VI） may be 97.00% in. In conclusion, the C. alternifolius has a high ability in accumulation of Cr and Ni, and is one of potential species for the great remediation of heavy metal pollution.