不同湿地植物的根系酸化作用与重金属吸收  

Variations among wetland plants in root acidification and heavy metal uptake

作　　者：李光辉[1] 杨霞[1] 徐加宽[2] 刘建国[1] 

机构地区：[1]江苏工业学院环境与安全工程学院,江苏常州213164 [2]常州市农林局,江苏常州213001

出　　处：《生态环境学报》2009年第1期97-100,共4页Ecology and Environmental Sciences

基　　金：江苏省普通高校研究生科研创新计划项目(CX08S_018Z);江苏省“青蓝工程”中青年学术带头人项目;常州市农业科技攻关计划项目(CE2008211)

摘　　要：为研究不同湿地植物根系分泌物对水体的酸化能力与重金属吸收积累能力间的关系,选用六种对废水中重金属吸收能力较强的湿地植物进行了盆栽实验。这六种湿地植物分别是:稗(Echinochloa crus-galli)、空心莲子草(Alternanthera philox-eroides)、茭笋(Zizania latifolia)、鸭舌草(Monochoria vaginalis)、柳叶箬(Isachne globosa)、辣蓼(Polygonum hydropiper)。研究结果表明,不同种类的植物对水体的酸化能力存在明显差异,水体 pH 差异最大可达 0.85 个单位;不同湿地植物间对重金属的吸收积累能力有显著差异,而且在重金属积累量方面的差异明显高于重金属浓度方面的差异。相关分析表明,不同湿地植物水体 pH 与植株重金属积累量之间存在较好的负相关关系,相关系数达到或接近 P0.05显著水平。研究结果说明,湿地植物对废水中重金属的吸收积累能力在相当大的程度上取决于其根系分泌物对水体的酸化能力。In order to investigate the relationships between root acidifications and heavy metal uptakes in different wetland plants, a pot experiment was conducted with six kinds of wetland plants as materials. The wetland plants are Echinochloa crus-galli, Alternanthera philoxeroides, Zizania latifolia, Monochoria vaginalis, Isachne globosa and Polygonum hydropiper. The results showed that there were obvious variations among the wetland plants in root acidification, and the largest difference between the plants in pot water pH was as much as 0.85 U. The variations among the wetland plants in heavy metal uptake were also significant, and the differences in metal quantity accumulations were larger than the differences in metal concentrations. Relationship analysis indicate that there are negative correlations between pot water pH and heavy metal accumulations in plants for the wetland plants studied, and the correlation coefficients reach or approach significant （P0.05） level. It can be concluded from the results that the abilities of wetland plants in heavy metal uptake from wastewater are determined considerably by the capacities of the plants in root acidification originated from root exudates.

关 键 词：湿地植物 根系分泌物 酸化 重金属 吸收 

分 类 号：X173[环境科学与工程—环境科学]