蚯蚓在植物修复菲污染土壤中的作用

Roles of Earthworm in Phytoremediation of Phenanthrene Contaminated Soil

采用盆栽试验法,研究了蚯蚓（Pheretima sp.）在植物修复菲污染土壤中的作用。结果显示,试验浓度（20.05-322.06 mg.kg-1）范围内,蚯蚓活动促进了菲污染土壤中修复植物黑麦草（Lolium multiforum）的生长,其根冠比明显增大。添加蚯蚓72 d后,种植黑麦草的土壤中菲的去除率高达64.35%-93.40%,其平均去除率（80.92%）比无蚯蚓活动的土壤-植物系统（71.57%）提高9.35%,比无植物对照组（22.58%）提高57.34%。各种生物、非生物修复因子中,植物-微生物交互作用对菲去除的平均贡献率（53.56%）最为突出,比无蚯蚓活动时（47.48%）提高6.08%。说明蚯蚓活动可强化土壤-植物系统对土壤菲污染的修复作用。

A pot experiment was carried out to study effect of earthworm（Pheretima sp.）on ryegrass（Lolium multiforum）remedying soils polluted by phenanthrene（Phe）in a green house.Results showed that earthworm activity promoted growth of ryegrass in spiked soils with initial concentrations of Phe ranging from 20.05 to 322.06 mg.kg-1,and apparently increased its root/shoot ratio.Seventy-two days after earthworm was introduced in,the Phe removal rate reached 64.35%~93.40%,and averagely 80.92% of Phe was removed from the soils plant-ed,which was 9.35% higher than that in the treatment planted without earthworm introduced in,and 57.34% higher than that in the treatment unplanted without earthworm introduced in,respectively.Among all the remedying factors（i.e.abiotic loss,phytodegredation,plant accumu-lation,microbial degradation,earthworm accumulation and plant-microbial interaction）,the plant-microbial interaction contributed the most,about 53.56% of the total removal,6.08% higher in the treatment with earthworm introduced in than in the treatment without earthworm（i.e.47.48% of Phe）.The findings suggested that introduction of earthworm may be a feasible way for establishing high efficiency phytoremedia-tion of soil polluted with polycyclic aromatic hydrocarbons（PAHs）by removing Phe from the soil-plant system,especially for decreasing crop accumulations to PAHs and reducing its ecological risks.