In situ phytoremediation of PAHs contaminateds soils in a mixed cropping system
植物混种原位修复多环芳烃污染农田土壤

In-situ phytoremediation of PAHs contaminated soils in the monoculture and mixed cropping was investigated by the number of soil microbe,PAHs-degrading microbe,PAHs concentration in plant and soil.The results showed that,removal rates of PAHs in mixed cropping treatments of ryegrass/horsebean and ryegrass/wheat were 59.4% and 64.8%,respectively.At the same time,the numbers of soil bacterium,fungi and PAHs-degrading microbe in ryegrass mixed cropping treatments were significantly more than those of the monoculture cropping of wheat,horsebean and ryegrass.In different parts of plants,the order of PAHs concentration was as following: root>shoot≈seed.PAHs concentration within different parts of plants in mixed cropping treatments decreased at different degrees when contrasted with those of monoculture treatments,especially in seed.The results suggested in-situ phytoremediation of PAHs contaminated soils in a mixed cropping system improved removal efficience of PAHs in soils and decreased acccumulation of PAHs in crops,and had a broad prospect for realization of the PAHs remediation in the farming agricultural soils.