关键词: 河道底泥, Cd, 植物修复, 优选试验, 龙葵

Abstract: Twelve plants were selected to conduct an experimental study on remediation of Cd contaminated sediment of black-odor river in Shanghai. Tolerance, enrichment and translocation features, and remediation efficiencies of plants to the heavy metal were investigated, with a view to find practical application of phytoremediation of river sediments polluted by Cd. Results revealed that all the plants except the transplanted Juncus effusus L. showed good tolerance to the sediment. The above-ground Cd contents of Solanum nigrum L., Juncus effusus L., Calendula officinalis L., Hylotelephium erythrostictum (Miq.) H. Ohba, and Farfugrium japonicum (L. f.) Kitam. were higher than 4.50 mg/kg. The bioaccumulation factors (BCFs) and translocation factors (TFs) of Cd in Abutilon theophrasti Medicus, Juncus effusus L., Calendula officinalis L., Hylotelephium erythrostictum (Miq.) H. Ohba, Farfugrium japonicum (L. f.) Kitam. and Phytolacca americana L. were greater than 1. The extraction amounts of Cd in Solanum nigrum L., Calendula officinalis L., Phytolacca americana L. and Bidens pilosa L. were higher than 0.30 kg/hm², and had relatively good remediation effects. Among the plants, the extraction amount and extraction efficiency of Solanum nigrum L. for Cd in the sediment were up to 2.84 kg/hm² and 88.75%, respectively, indicating great remediation potential. The optimization test proved that Solanum nigrum L., as the best remediation plant, could be used to remediate the Cd contaminated river sediment in this area.

Key words: River sediment, Cd, phytoremediation, optimization test, Solanum nigrum L