4种牧草植物对红枫湖底泥中重金属污染的植物修复研究

为研究牧草对红枫湖底泥中复合重金属的修复潜力,采用盆栽试验考察了4种牧草植物对红枫湖底泥中Zn、Cu、Pb、Cd的吸收能力和底泥修复效率的差异。结果表明:种植4种牧草植物后,底泥中重金属Zn、Cu、Pb、Cd含量均有所降低。高羊茅对Zn的吸收能力较强,且主要积累在地上部分;黑麦草对Cu和Pb的吸收能力较强,且主要积累在根系;4种植物对Cd的吸收能力相差不大,除菊苣的Cd主要积累在地上部分外,其余植物都积累在根系。黑麦草对底泥中Cu、Pb和Cd的修复效率高于其他3种植物,分别为38.69%、17.12%和31.68%;高羊茅对底泥中Zn的修复效率相对较高,为55.03%,且其Zn的转移系数大于1,反映出其对红枫湖底泥中Zn具有植物提取的潜力。

STUDY ON PHYTOREMEDIATION OF HEAVY METALS IN THE SEDIMENTS OF HONGFENG LAKE BY FOUR SPECIES OF PASTURE GRASS

A pot experiment was conducted to study the accumulation and remediation efficiency of four different pasture grass ( Lolium perenne，Medicago sativa，Festuca arundinacea，Cichorium intybus) to heavy metals ( Zn，Cu，Pb，Cd) in the sediments of Hongfeng Lake． The results revealed that the heavy metals concentration decreased after planting the different pasture grass． The accumulation ability of Festuca arundinacea to Zn was relatively higher than the others，and Zn mainly accumulates within its shoots． For Cu and Pb，the accumulation abilities of Lolium perenne were relatively higher and mainly accumulate them within its roots． The differences in accumulation abilities of four plants to Cd were certainly small，and Cd mainly accumulate within the roots except Cichorium intybus ( within its shoots) ． Phytoremediation efficiencies of Lolium perenne on Cu、Pb and Cd were 38. 69%，17. 12%，31. 68%，respectively and higher than the others． Festuca arundinacea has higher remediation efficiency on Zn ( as high as 55. 03%) ． Furthermore，the translocation factor of Festuca arundinacea exceeded 1. 0，which suggested phytoextraction potentiality of Zn from the sediments．