杨树、落叶松对土壤重金属的吸收及修复研究

Study on absorption and remediation by Poplar and Larch in the soil contaminated with heavy metals

在沈阳生态实验站开展了木本植物对土壤重金属的吸收积累及修复效应的研究,实验结果表明,重金属污染物已影响了杨树(Populus canadensis)的正常生长,Cd、Cu、Zn复合污染处理杨树总生物量比对照下降了26%。Cd、Cu、Zn处理杨树和落叶松重金属吸收量多于对照,杨树叶Cd、根Cu重金属吸收量分别比对照增加了2.09倍、2.2倍。落叶松(Larix koreana)根Cd、Cu、Zn的吸收量比对照分别增加了2.17、1.95和1.42倍。树木体内重金属元素迁移能力的大小分别为Cd>Zn>Cu,重金属吸收系数大小依次为杨树>落叶松,重金属在杨树体内的迁移能力及地上部吸收能力要大于落叶松。土壤一旦遭受重金属污染(Cd、Cu、Zn),通过木本植物杨树、落叶松修复净化的时间相当漫长。

Field experiments in Shenyang Ecological Experimental Station were conducted to study the absorption, accumulation and remediation of heavy metals by woody plants in polluted soils. The result showed that the biomass of poplar （Populus canadensis Moench） in the Cd, Cu and Zn combined treatment decreased 26.02 % compared with the control. Content levels of Pb in poplar leave increased 2.09 times and Cu in poplar root increased 2.2 times compared with control. Content levels ofCd, Cu and Zn in roots of larch （Larix olgensis Henry） increased 2.17, 1.95 and 1.42 times compared with control respectively. The migration ability of heavy metals in woody plant body was in the order of Cd〉Zn〉Cu. The abilities of translation and uptake of heavy metals for poplar is greater than larch. Poplar and Larch were applied for soil phytoremediation will take several hundred years, once the soils were heavy polluted by heavy metals （Cd, Cu and Zn）.