螯合诱导植物修复中污染土壤的重金属淋滤行为  

The leaching behavior of heavy metals in contaminated soils during the process of chelant-enhanced phytoremediation

作　　者：陈亚华[1] 刘亮[1] 王桂萍[1] 郭强[1] 朱迪[1] 沈振国[1] 

机构地区：[1]南京农业大学生命科学学院,江苏南京210095

出　　处：《南京农业大学学报》2007年第4期46-51,共6页Journal of Nanjing Agricultural University

基　　金：江苏省社会发展项目(BS2006055);江苏省自然科学基金(BK2006711-1);南京农业大学SRT计划(0409A10;0506A02)

摘　　要：采用土柱淋滤试验,研究乙二胺二琥珀酸(EDDS)和乙二胺四乙酸(EDTA)诱导植物修复过程中的土壤重金属淋滤行为,同时比较了香根草(Vetiveria zizanioidesL.)和玉米(Zea maysL.)在减少重金属淋滤方面的作用。结果表明,在25 d内经过480 mm降雨的淋洗,EDDS处理的土柱(80 cm土层)没有出现重金属的淋滤;而EDTA明显导致表层土壤重金属向下层土壤迁移,该迁移行为与降水量的大小、种植植物与否关系密切。香根草和玉米可明显延缓EDTA引起的土壤重金属向下层土壤的淋滤,且香根草的延缓效果好于玉米。上述结果表明,EDDS诱导的高生物量植物修复是相对安全的,而使用EDTA需要考虑当地的降水条件。Using soil column-leaching test, the leaching behavior of heavy metals in soils was studied in the process of EDDS or EDTA-enhanced phytoextraction, and the roles of high-biomass plants （ corn and vetiver grass ） on the decrease of heavy metals leaching were also examined. Results showed that, application of EDDS into soil surface did not lead to the leaching of heavy metals from the soil columns （80 cm in height） after 480 mm of rainfall percolation within 25 days. However, EDTA application led to the migration of heavy metals from up-soil to deep-soil in the columns, and the migration of metals tightly related to the amount of added rainwater and with or without planting. The seedlings of corn or vetiver grass could be effectively delay the movement of heavy metals downward, and vetiver grass showed more effective than corn. This implies that, combined planting with some high-biomass plants, EDDS can be regarded as a good chelator candidate for the environmentally safe phytoextraction heavy metals from contaminated soils. It should be careful to use of EDTA in the field phytoremediation, especially in some heavily raining areas.

关 键 词：土柱淋滤试验 重金属污染土壤 植物修复 香根草 玉米 乙二胺二琥珀酸 乙二胺四乙酸 

分 类 号：X53[环境科学与工程—环境工程]