人工湿地宽叶香蒲对重金属的累积与机理  

Accumulation and mechanism of heavy metals in Typha latifolia L. in constructed wetland

作　　者：李冰[1] 舒艳[1] 李科林[1] 宋金风 聂文博[1] 汤春芳[1] 

机构地区：[1]中南林业科技大学林学院,长沙410004

出　　处：《环境工程学报》2016年第4期2099-2108,共10页Chinese Journal of Environmental Engineering

基　　金：湖南省教育厅科技项目(13C1141);湖南省科技厅计划项目(2012FJ3144)

摘　　要：宽叶香蒲（Typha latifolia L.）对环境胁迫具有较强的耐性。为了解宽叶香蒲对重金属的富集能力与耐性机理,通过野外调研,采集韶关凡口铅锌矿废水处理人工湿地中的宽叶香蒲与相应土壤样品,测定了土壤、植物的重金属总量与叶片亚细胞中重金属含量,分析了植物重金属含量与土壤重金属含量的相关性,并估算了宽叶香蒲地上部对重金属的提取量。土壤p H值在6.83～7.70之间,宽叶香蒲能有效降低土壤中的Cd、Pb、Zn、Cu和Mn的含量,对重金属的吸收主要受土壤重金属含量的影响,Pb和Cd的富集系数平均在0.5以上;除Fe外,叶片重金属主要分布在细胞壁和胞基质中。结果表明,宽叶香蒲是多种重金属的耐性植物,根系对重金属的富集与选择性向上运输、叶片细胞壁和胞基质对过量重金属的阻隔与结合作用是宽叶香蒲耐受重金属的重要机理。Typha latifolia L. has a high tolerance to environmental stresses. To understand the bioaccumulation capacity and tolerance mechanisms of broad-leaf cattails to heavy metals,T. latifolia tissues and corresponding soils were collected from a constructed wetland located in the Fankou lead and zinc mining area in Shaoguan City. Total heavy metal concentrations in the soil and plant samples,and subcellular content of heavy metals in leaves were determined. The correlations between heavy metal concentration in the soil,in the plant,and within plant tissues were analyzed. The p H values of soils ranged from 6. 83 to 7. 70,and the concentrations of Cd,Pb,Zn,Cu,and Mn in soils were efficiently reduced by broad-leaf cattails. Heavy metal uptake in T. latifolia was predominantly affected by metal content in the soil. Average bioaccumulation factors for Pb and Cd were above 0. 5,and heavy metals,except for Fe,were primarily distributed in the cell wall and cytoplasmic matrix in the leaves.The results indicated that T. latifolia is tolerant to several heavy metals. Root accumulation,select transportation of heavy metals to aerial parts,cell wall binding,and cytosol compartmentation of excess heavy metals are important mechanisms of the heavy-metal tolerance of T. latifolia.

关 键 词：宽叶香蒲 重金属 累积 机理 

分 类 号：X173[环境科学与工程—环境科学]