Phytoextraction of Metal-Contaminated Soil by Sedum alfredii H: Effects of Chelator and Co-planting
Phytoextraction of Metal-Contaminated Soil by Sedum alfredii H: Effects of Chelator and Co-planting
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DOI：
10.1007/s11270-006-9256-1
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发表时间：
2007-02
期刊：
影响因子：
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通讯作者：
Qi-Tang Wu;Ze-bin Wei;Ouyang Ying
中科院分区：
文献类型：
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作者：
Qi-Tang Wu;Ze-bin Wei;Ouyang Ying
植物提取是一种利用超积累植物去除土壤和沃茨中无机污染物（主要是重金属）的有前途的技术。通过田间试验，研究了螯合剂（MC）混合物对铅、锌污染稻田土壤中超积累植物东南景天（Sedum alfrediiHance）生长和提取重金属的影响。在这项研究中使用的共种植系统是由一个锌和镉超积累（S.alfredii）和低积累作物（玉米）。结果表明，添加MC和与Z.梅斯玉米籽粒中Zn、Pb、Cd含量符合中国饲料卫生标准，玉米其它部位符合中国有机肥标准。添加MC显著提高了Alfredii对Zn、Cd、Pb的吸收。与紫花苜蓿共植显著提高了苜蓿对Zn的吸收。而MC与间作的互作效应不显著，说明两种处理的效应是加性的。当MC施用于受锌、镉和铅污染的土壤中的共种植系统时，观察到最高的植物提取率。本研究表明，在复合种植系统中，超积累植物阿尔佛雷德和低积累作物玉米在添加MC的情况下联合使用比单一超积累植物在EDTA（乙二胺四乙酸）的辅助下使用更有前途。这种方法不仅提高了重金属的植物提取率，而且同时允许在金属污染的土壤中使用安全的饲料产品的农业实践。
Phytoextraction is a promising technology that uses hyperaccumulating plants to remove inorganic contaminants, primarily heavy metals, from soils and waters. A field experiment was conducted to evaluate impacts of a mixture of chelators (MC) upon the growth and phytoextraction of heavy metals by the hyperaccumulatorSedum alfrediiHance in a co-planting system in a paddy soil that was historically irrigated with Pb and Zn contaminated mining wastewaters. The co-planting system used in this study was comprised of a Zn- and Cd-hyperaccumulator (S.alfredii) and a low-accumulating crop (Zea mays). Results showed that yields ofS.alfrediiwere significantly increased with the addition of the MC and by co-planting withZ. mays. Our study further revealed that concentrations of Zn, Pb, and Cd in the corn grains ofZ.maysconform to the Chinese hygiene standards for animal feeds and in the other parts ofZ.maysconform to the Chinese organic fertilizer standards. The uptake of Zn, Cd, and Pb byS.alfrediiwas significantly increased with the addition of MC. The uptake of Zn byS.alfrediiwas also significantly enhanced by co-planting withZ. mays, but the interaction between MC and co-planting was not significant, meaning the effects of the two types of treatments should be additive. When the MC was applied to the co-planting system in the soil contaminated with Zn, Cd, and Pb, the highest phytoextraction rates were observed. This study suggested that the use of the hyperaccumulatorS.alfrediiand the low-accumulating cropZ.maysin the co-planting system with the addition of the MC was a more promising approach than the use of a single hyperaccumulator with the assistance of EDTA (ethylenediaminetetraacetic acid). This approach not only enhances the phytoextraction rates of the heavy metals but also simultaneously allows agricultural practices with safe feed products in the metal-contaminated soils.