Evaluation of heavy metals accumulation by two emergent macrophytes from the polluted soil: an experimental study

摘要

The concentrations of copper (Cu) and lead (Pb) in, and the biomass of, the different parts of Persicaria glabra (Willd.) Gamez and Juncellus alopecuroides (Rottb.) C.B.C1. were evaluated while grown in pots under laboratory conditions. Cu and Pb were added as sulphates (50, 100, 200, 400 mg/kg) to the pots. Heavy metal concentrations in the plants were measured by atomic absorption spectrometry. Results reveal that the biomass of J. alopecuroides (particularly roots) was higher than P. glabra, and that the growth tendency of macrophytes decreased with increasing heavy metal concentration in the soil, while in P. glabra, biomass went on increasing with the increase in copper concentration. Heavy metal accumulation in the roots was more than in aerial parts, and, therefore, barring two exceptions, the transfer factor of heavy metals from roots to aerial parts showed as less than 1, suggesting less transfer of heavy metals from roots to aerial parts. Thus, these macrophytes are efficient accumulators of trace elements, particularly J. alopecuroides, which can be recommended for biofiltration of heavy metals from contaminated soils.