Abstract:
The organic pollutants of polycyclic aromatic hydrocarbons (PAHs) can existinthesoil environment for a long time. They could pose a great threat to human health and cause inestimable damage once they were infiltratedinto the food chain. Phytoremediationis an environmentally friendly and cost-effective approach for the remediation of PAHs contaminated soil due to the rhizospheric effect on removing PAHs pollutants from soil. So it is significant to study the mechanism of rhizosphere effecton the phytoremediation of PAHs contaminated soil. This review summarized therelative researchprogress, showing that various plants of monocotyledons poaceae had better toleranceand remediation potential to remove PAHs from the contaminated soil. It was demonstrated that the combinationremediation of multiple plants could be the most advantageous approach than that of single plant. The root exudates with low-molecular-weight organic acids (LMWOAs) released by the remediation plants combined with PAHs pollutants in the surrounding environments formeda feedback loop to determine the fate of PAHs in the phytoremediation. The root exudates of the remediation plants could be used to establish the specific rhizospheric microflora that could degrade PAHs byseveral different mechanisms. Aiming at a series of problems existed at present in the rhizosphere effects of PAHs phytoremediation, the key points and directions concerned in the future research were proposed, based on the review of the perspectives of roots, root exudates, rhizosphere microorganisms and their interactions, in order to provide a scientific basis and a theoretical reference for the development of phytoremediation technology inthe PAHs polluted soil.