芦苇、菖蒲和水葱对水体中Pb^(2+)富集能力的研究

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

通过对照处理和5mg/L、10mg/L、30mg/L、60mg/L、100mg/L和150mg/L6个Pb2+浓度溶液的水培试验,分析了菖蒲(Acorus calamus)、芦苇(Phragmites australis)和水葱(Scirpus tabernaemontani)的不同生长部位对于Pb2+的积累效果。结果表明,水葱、菖蒲和芦苇体内地上部分和地下部分的Pb2+含量均随着水溶液中污染物浓度的增大而增加,表现出显著的正相关关系。在同一Pb2+浓度处理条件下,水葱、菖蒲、芦苇体内的Pb2+含量存在显著差异,菖蒲地下和地上部分富集的Pb2+含量最高,表现出较强的富集能力。水葱地下部分对Pb2+的富集能力在各个浓度处理条件下均高于地上部分;在对照处理和较低处理浓度下,芦苇与水葱相同,地下部分Pb2+积累浓度高于地上部分,而菖蒲则是地上部分的富集浓度高于地下部分;在较高浓度处理条件下,菖蒲和芦苇地上部分的富集浓度较地下部分高。3种湿地植物在高浓度的Pb2+处理条件下,均表现出较强的富集能力,可作为植物修复重金属污染水体的遴选物种。

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, Pb^2＋ accumulation content in different parts of Phragmites australis, Acorus calamus, Scirpus tabernaemontani were investigated based on hydroponic experiments of different Pb^2＋ concentration solutions in the study, and the concentrations of Pb^2＋ 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 Pb^2＋ concentration for above - ground parts and under - ground of Phragmites australis, Acorus calamus, Scirpus taber- naemontani. Pb^2＋ contents in above - ground and under - ground parts of the three wetland plants usually increased with the Pb^2＋ concentrations of hydroponic solution, and there were significantly positive correlation between Pb^2＋ contents and concentrations of hydroponic solution. There was significantly difference in Pb^2＋ contents among the three wetland plants under each treatment of Pb^2＋ concentrations of hydroponic solution. The highest Pb^2＋ 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 Pb^2＋ concentrations, Pb^2＋ accumulated in the under - ground parts of Scirpus tabernaemontani were always higher than the above - ground parts. At lower Pb^2＋ concentration treatments, Phragmites australisu performed same responses with Scirpus tabernaemontani, but Pb^2＋ accumulated in the under-ground parts of Acorus calamus were lower than the above-ground parts. At the highest Pb^2＋ concentration treatment, Pb^2＋ 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 Pb^2＋ accumulation ability of them under the higher Pb^2＋ concentration treatments.