Accumulation Ability of Phragmites australis,Acorus calamus and Scirpus tabernaemontani for Pb~(2+) in Water Body

Pb is the most common heavy metal contaminant in the environment.The engineering and technology of construct wetland have been used to control the pollution of water due to its economy and efficiency and the hydrophytes were the most important constituents of construct wetland.In April,2008,Pb2+ accumulation content in different parts of Phragmites australis,Acorus calamus,Scirpus tabernaemontani were investigated based on hydroponic experiments of different Pb2+concentration solutions in the study,and the concentrations of Pb2+ of the water body were 0 mg/L,5 mg/L,10 mg/L,30 mg/L,60 mg/L,100 mg/L and 150 mg/L,respectively.The results showed that there were significantly differences among 3 wetland plants and among treatments of Pb2+ concentration for above-ground parts and under-ground of Phragmites australis,Acorus calamus,Scirpus tabernaemontani.Pb2+ contents in above-ground and under-ground parts of the three wetland plants usually increased with the Pb2+ concentrations of hydroponic solution,and there were significantly positive correlation between Pb2+ contents and concentrations of hydroponic solution.There was significantly difference in Pb2+ contents among the three wetland plants under each treatment of Pb2+ concentrations of hydroponic solution.The highest Pb2+ concentrations always occurred in above-ground parts and under-ground of Acorus calamus,and Acorus calamus performed the greatest accumulation ability.At each treatment of Pb2+ concentrations,Pb2+ accumulated in the under-ground parts of Scirpus tabernaemontani were always higher than the above-ground parts.At lower Pb2+ concentration treatments,Phragmites australisu performed same responses with Scirpus tabernaemontani,but Pb2+ accumulated in the under-ground parts of Acorus calamus were lower than the above-ground parts.At the highest Pb2+ concentration treatment,Pb2+ concentrations accumulated in the above-ground parts of Phragmites australisu and Acorus calamus were greatly higher than the under-ground parts.Phragmites australis,Acorus calamus,Scirpus tabernaemontani can been selected to application on phytoemediation of water polluted by heavy metal due to the excellent Pb2+ accumulation ability of them under the higher Pb2+ concentration treatments.