碱蓬对Pb^(2+)、Cd^(2+)单一及复合胁迫的反应及其吸收累积特征  

Responses and Accumulation Characteristics of Suaeda Salsa Under Combined and Single Stress of Pb^(2+) and Cd^(2+)

作　　者：杨佳[1] 王趁义[1] 陈翟[1] 滕丽华[1] 高宇超 郝琦玮[1] 赵欣园 

机构地区：[1]浙江万里学院生物与环境学院,浙江宁波315100

出　　处：《水土保持学报》2016年第2期323-327,共5页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(31071856);浙江省自然科学基金项目(LY16C150002);浙江省公益性技术应用研究计划项目(2015C32035);宁波市社发攻关项目(2014C50057);宁波市农业局项目(2013ST002)

摘　　要：采用室外盆栽模拟方法,比较并分析了Pb^(2+)、Cd^(2+)单一及复合胁迫对碱蓬生长的影响及其对Pb^(2+)、Cd^(2+)的吸收和累积规律。结果表明:在单一Pb^(2+)、Cd^(2+)胁迫下,低浓度时(Pb^(2+)20mg/kg、Cd^(2+)5mg/kg)促进碱蓬生长,高浓度时(Pb^(2+)200mg/kg、Cd^(2+)≥20mg/kg)抑制碱蓬生长,富集系数(BF)均>1。Pb^(2+)、Cd^(2+)复合胁迫时,情况较复杂,既有拮抗作用,又有协同作用,与2种重金属浓度密切相关。碱蓬对Cd^(2+)的BF受Pb^(2+)影响显著,且均>1,表明碱蓬是Cd^(2+)的超富集植物;碱蓬对Pb^(2+)的BF主要受Pb^(2+)自身浓度大小的影响,当Pb^(2+)浓度≤200mg/kg时Pb^(2+)的BF>1,Pb^(2+)浓度>200mg/kg时碱蓬对Pb^(2+)的BF反而减小,且<1,加入Cd^(2+)对其影响不显著。碱蓬对Pb^(2+)、Cd^(2+)的富集吸收模式基本符合简单二次方程,这为研究碱蓬在Pb^(2+)、Cd^(2+)复合胁迫下的吸收累积机制提供理论依据,有利于碱蓬被应用于Pb^(2+)、Cd^(2+)污染的高盐碱地区的植物修复实践。Effects of single and combined pollution of Pb^2＋and Cd^2＋on the growth of Suaeda salsa and its uptake and accumulation abilities for Pb^2＋and Cd^2＋were measured and analyzed through an outdoor pot experiment.The results showed that under the single stress of Pb^2＋and Cd^2＋,low concentration of Pb^2＋and Cd^2＋（Pb^2＋20mg/kg,Cd^2＋5mg/kg）could promote the growth of Suaeda salsa,while high concentration（Pb^2＋200 mg/kg,Cd^2＋≥20 mg/kg）could inhibit its growth,and all bioaccumulation factors（BF）were higher than 1.The interaction of Pb^2＋and Cd^2＋showed synergy as well as antagonism under the Pb^2＋and Cd^2＋combined stress.The BF of Suaeda salsafor Cd^2＋was larger than 1,and was significantly affected by Pb^2＋,which indicated that Suaeda salsais the hyperaccumulator of Cd^2＋.The BF of Suaeda salsafor Pb^2＋was smaller than 1,and was mainly affected by Pb^2＋concentration.The BF of Pb^2＋was larger than 1when the concentration of Pb^2＋was no more than 200mg/kg,while the BF of Pb^2＋decreased and was smaller than1 when Pb^2＋concentration was larger than 200mg/kg.The addition of Cd^2＋did not significantly affect the BF of Pb^2＋.The modes of uptake and accumulation of Pb^2＋and Cd^2＋in Suaeda salsa under the single and combined stress of Pb^2＋and Cd^2＋basically fitted to quadratic equations.This study can provide a theoretical basis for the mechanisms of uptake and accumulation of Pb^2＋and Cd^2＋in Suaeda salsa and will contribute to the application of the phytoremediation for Pb^2＋and Cd^2＋pollution in saline area.

关 键 词：碱蓬 PB^2+ CD^2+ 复合胁迫 

分 类 号：X171.4[环境科学与工程—环境科学] X173