锌胁迫下湿地植物抗氧化系统反应及锌富集能力  

Antioxidant system responses and bioaccumulation of Zn in wetland plants under Zn stress

作　　者：杨俊兴[1,2] 胡健[2] 雷梅[2] 杨军[2] 郭俊娒[2] 曹绍宽 叶志鸿[1] 曹柳 

机构地区：[1]中山大学生命科学学院,广州510006 [2]中国科学院地理科学与资源研究所环境修复中心,北京100101 [3]云南省蒙自市农业局,昆明661100 [4]济源市环境科学研究所,河南济源459000

出　　处：《生态学杂志》2017年第8期2274-2281,共8页Chinese Journal of Ecology

基　　金：国家高技术研究计划项目(2013AA06A211-2);国家自然科学基金项目(30570345;41201312)资助

摘　　要：湿地植物作为人工湿地的主要成分之一,在提高湿地处理重金属污染物效率上有着至关重要的作用。通过盆栽试验研究了对照(CK)、600、1200 mg Zn·kg^(-1)3种处理条件下,18种挺水湿地植物的生长状况、Zn耐性指数、叶片可溶性蛋白、抗氧化系统及对Zn的吸收转运能力。结果表明,随着Zn浓度的增加,供试植物的生物量、耐性指数和叶片可溶性蛋白减少,植物地上和地下部分的Zn浓度增加。不同湿地植物Zn耐性指数和Zn富集能力差异显著(P<0.05),在600和1200 mg Zn·kg^(-1)条件下,石菖蒲(Acorus tatarinowii)的耐性最高。大部分供试植物地下部分Zn含量显著高于地上部分,根系对Zn有较强的滞留效应。在600 mg Zn·kg^(-1)条件下,大部分供试植物叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)显著增加。研究显示,湿地植物除了通过根系对Zn有较强的滞留作用外,还通过体内的抗氧化系统有效地清除细胞内过多的活性氧,进而缓解过量Zn带来的胁迫。本研究结果为湿地植物修复Zn污染土壤和水体技术提供了有力的理论依据。Constructed wetlands are considered as an effective and lowcost technology to clean up toxic metals such as zinc （Zn） from contaminated wastewater. The effect of Zn treatment on biomass, Zn tolerance, soluble protein and antioxidant enzymes of leaves in 18 candidate wetland emergent plants grown in soils without （control, CK） and spiked with 600 and 1200 mg Zn·kg-1 were studied in a pot trial. The results showed that there were significant differences in Zn tolerance indices and accumulation among the 18 plant species. The biomass, Zn tolerance indices and leaf protein contents of the 18 plant species decreased with the increasing soil Zn concentrations. Activities of superoxide dismutase （SOD）, peroxidase （POD） and catalase （CAT） in leaves of most of the 18 plant species increased with the increasing soil Zn concentrations. Zinc accumulation by the 18 plant species was strongly dependent on the plant species and soil Zn concentration. However, Zn translocation from root to shoot was generally low in the 18 plant species. Enhancement of SOD, POD and CAT activities revealed that the antioxidant system of wetland plants played an important role in alleviating Zn toxicity in the 18 plant species. The data obtained should help to select proper wetland plant species for use in remediating Zncontaminated wastewater and soils.

关 键 词：锌 重金属污染 湿地植物 植物修复 抗氧化系统 

分 类 号：X173[环境科学与工程—环境科学]