通过温室盆栽试验,研究鸭跖草(Commelina communis Linn.)对Cd的耐性和富集特征。结果表明,鸭跖草的根系生物量随着土壤Cd浓度的增加先增加后恢复正常,茎、叶、地上部生物量随着土壤Cd浓度的增加先增加然后下降最后恢复正常。鸭跖草各部位的干重在土壤Cd浓度为8 mg/kg时最大,在60 mg/kg时达到最低,在100 mg/kg时与未污染情况时相当。植物体内的Cd浓度和提取量随土壤中Cd浓度的增加,当土壤中Cd浓度为100 mg/kg时,鸭跖草根部、茎和叶的Cd浓度和提取量达到最大,分别为281、35、34 mg/kg,Cd提取量分别为98、30、30μg/株。研究结果表明,鸭跖草是Cd的耐性植物,可应用于Cd污染土壤的植物稳定技术或矿山废弃地的植被重建。
A pot experiment was conducted in a greenhouse to evaluate the cadmium tolerance and accumulation characteristics of Commelina communis Linn. The dry weight of plant increase with the Cd concentration increase in soil, and was maximum when soil Cd concentration was 8 mg/kg. Then the dry weight of plant decrease and was minimum at soil Cd 60 mg/kg. However, the dry weight of plant was not influenced by 100 mg/kg Cd pollution. Cadmium concentration and extraction amounts of C. communis increased as the Cd concentration increased in soil and were the maximum when soil Cd was 100 mg/kg. When soils were contaminated by 100 mg/kg Cd, C. communis accumulated 281, 35 and 34 mg/kg Cd in roots, stem and leaf, respectively, with 98, 30 and 30 μg/plant Cd extraction amounts. The study results indicated that C. communis has strong tolerance to Cd, and could be regarded as a candidate species for phytostabilization of Cd contamination.