Multispecies Phytoremediation on Degradation of PAHs in Soils

Potentials of three plant species, rape, alfalfa and white clover, separately or jointly on the degradation of polycyclic aromatic hydrocarbons (PAHs) in soil were estimated by pots experiments. Results showed the presence of vegetation apparently enhanced the dissipation of PAHs at initial concentrations ranging from 20.05 to 322.06 mg·kg-1. Within 70-day experiment, alfalfa and white clover showed higher efficiencies for removal of PAHs than those of rape, and mixed cropping greatly enhanced the dissipation of PAHs as compared to single cropping. On average 74.87% of phenanthrene or 62.81% of pyrene were removed from soils with mixed cropping of rape and alfalfa, and 72.01% of phenanthren or 68.44% of pyrene removed by mixed cropping of rape and white clover. Results suggested a feasibility of the establishment of multispecies remediation for enforcing the dissipation of PAHs.