蚯蚓活动对金发草修复土壤菲芘污染的强化作用

EFFECT OF EARTHWORM REINFORCING POGONATHERUM PANICEUM REMEDIATION OF PHENANTHRENE/PYRENE POLLUTED SOIL

采用盆栽试验法，研究了蚯蚓（Pheretima sp．）对金发草（Pogonatherum paniceum L．）修复菲、芘污染土壤的强化作用。结果显示，在试验浓度范围（20．1～322．1mg kg-1）内，蚯蚓活动促进了菲、芘污染土壤中金发草的生长，其根冠比明显增大。添加蚯蚓70d后，种植金发草的土壤中菲、芘的平均去除率高达77．0％、70．6％，平均去除率分别较无蚯蚓作用时（68．7％、61．2％）增长了8．3％、9．5％；相同污染水平下，蚯蚓活动对芘的强化去除程度总是大于菲。各修复因子中，植物-微生物交互作用对菲、芘去除的平均贡献率（46．6％、42．8％）最为突出，分别较无蚯蚓活动时（41．6％、36．6％）增长了5．0％、6．1％。说明蚯蚓活动可强化土壤-植物系统对土壤中菲、芘污染的去除作用。

A pot experiment was carried out to study effect of earthworm （Pheretima sp. ） on Pogonatherum panice- um remedying soils polluted by phenanthrene （Phe） and pyrene （Pyr） in. Results show that earthworm activity promoted growth of Pogonatherum paniceum in soils with initial concentrations of Phe and Pyr ranging from 20. 1 to 322. 1 mg kg-1, and apparently increased its root/shoot ratio. Seventy days after earthworm was introduced in, the average Phe and Pyr removal rate reached 77.0% and 70. 6%, respectively, 8.3% and 9.5% higher than that in the treatment without earthworm introduced in, respectively. Apparently, the effect of earthworm activity on removal of Phe was greater than of Pyr. Among all the remedying factors, the plant-microbial interaction contributed the most, about 46.6% and 42. 8% to the total removal of Phe and Pyr, respectively 5.0% and 6. 1% higher in the treatment with earthworm introduced in than in the treatment without earthworm （ i. e. 41.6% of Phe and 36.6% of Pyr）. The findings suggested that introduction of earthworm may enhance phytoremediation of soil polluted with PAHs by removing Phe and Pyr from the soil-plant system.