东方香蒲（Typha orientalis Presl）对重度污染土壤中As、Cd、Pb的耐性与累积特征

通过温室盆栽试验研究东方香蒲对重度污染土壤中As、Cd、Pb的耐受性能与累积特征。研究结果表明,与未污染土壤处理相比,当土壤中As、Cd、Pb含量分别达到48.4、16.9mg·kg-1和316mg·kg-1时,东方香蒲生物量、叶绿素含量和过氧化氢酶活性等均无显著降低,东方香蒲对土壤中As、Cd、Pb表现了较强的耐受性能;当土壤中As、Cd、Pb含量分别达到285、42.1、1008mg·kg-1时,东方香蒲生物量、叶绿素含量和过氧化氢酶活性等均明显下降（P〈0.05）,表现出植株矮小、叶片枯黄等中毒症状。东方香蒲对土壤中As、Cd、Pb的累积主要在根部,其含量分别可达31.69、35.12mg·kg-1和87.12mg·kg-1,而在茎叶中仅为2.06、2.83mg·kg-1和20.18mg·kg-1,根部向地上部转移系数小。研究结果表明,东方香蒲可作为As、Cd、Pb重度污染土壤植物稳定修复的潜在目标植物之一。

Tolerance and Accumulation Characteristics of Typha orientalis Presl for As,Cd and Pb in Heavily Contaminated Soils

The tolerance and accumulation characteristics for As,Cd and Pb in contaminated soils by Typha orientalis Presl were studied in greenhouse.The results showed that the biomass,chlorophyll content and catalase activities of Typha orientalis Presl had slight difference compared to the control,and Typha orientalis Presl possessed strong tolerance capacity for As,Cd and Pb in soils when concentrations of As,Cd and Pb in tested soils reached 48.4,16.9 mg·kg-1 and 316 mg·kg-1.When concentrations of As,Cd and Pb in tested soils reached 285,42.1 mg·kg-1 and 1 008 mg·kg-1,however,those indices of Typha orientalis Presl were significant decreased（P0.05）,and toxic symptoms of the plant,such as shoots stunted,leaves withered and yellow,were observed.As,Cd and Pb from the soil were mainly accumulated in roots of Typha orientalis Presl and the concentration of these elements reached 31.69,35.12 mg·kg-1 and 87.12 mg·kg-1,while the concentration of these elements in shoots were only 2.06,2.83 mg·kg-1 and 20.18 mg·kg-1,respectively.The transferring coefficient of As,Cd,and Pb from roots into shoots of Typha orientalis Presl was slight.Finally,Typha orientalis Presl is a suitable pioneer plant for phytostabilization of As,Cd and Pb heavily-contaminated soils.