The Guangxi Key Laboratory of Environmental Engineering, Protection and Assessment, Guilin University of Technology, Guilin, Guangxi 541004, China.
J Hazard Mater. 2011 Apr 15;188(1-3):85-91. doi: 10.1016/j.jhazmat.2011.01.066. Epub 2011 Jan 22.
Research on the phytoextraction of Cr from contaminated soils has been scarce, because very few plant species have been reported to accumulate Cr to high concentrations in their aerial parts. In this study, a Cr-hyperaccumulator, Leersia hexandra was investigated for its potential to remove Cr from the soil in a series of pot experiments. The results showed that L. hexandra had a high extraction capacity for chromium in soil, with the highest Cr concentration in shoot of 1844 mg/kg. Model calculation based on the negative linear relationship between the bioconcentration factors (BCF) and the concentrations of soil Cr indicated that phytoremediation using L. hexandra was feasible when soil was only moderately contaminated with Cr. Three sequential harvests did not significantly alter Cr accumulation and shoot biomass (p > 0.05), indicating that sequential harvest might be an available and convenient way to achieve the decontamination of Cr-contaminated soils by L. hexandra. On average, fertilization increased the shoot biomass by 45% and the total amount of extracted-Cr by 26%, suggesting that fertilization is able to enhance Cr phytoextraction of L. hexandra. Although EDTA increased the concentrations of Cr in shoots by 1.4 times, it also resulted in low plant biomass, thereby decreasing the amount of Cr accumulation.
从污染土壤中提取铬的研究很少，因为很少有植物物种被报道能够在其地上部分积累高浓度的铬。在这项研究中，研究了一种铬超富集植物，显脉香茶菜（Leersia hexandra），以研究其从土壤中去除铬的潜力。结果表明，显脉香茶菜对土壤中铬的提取能力很高，其地上部分的铬浓度最高可达 1844mg/kg。基于生物浓缩因子（BCF）与土壤铬浓度之间的负线性关系的模型计算表明，当土壤仅受到中度铬污染时，利用显脉香茶菜进行植物修复是可行的。三次连续收获并没有显著改变铬的积累和地上生物量（p＞0.05），这表明连续收获可能是一种可用且方便的方法，可实现显脉香茶菜对铬污染土壤的修复。平均而言，施肥使地上生物量增加了 45%，提取的铬总量增加了 26%，这表明施肥能够增强显脉香茶菜对铬的植物提取。虽然 EDTA 使地上部分的铬浓度增加了 1.4 倍，但也导致了植物生物量的降低，从而减少了铬的积累量。
