Distribution by influence factors of pyrene removal in chemical enhancers assisted microbial phytoremediation of Scirpus triqueter in co-contaminated soils

The rehabilitation of soil co-contaminated by heavy metals and polycyclic aromatic hydrocarbons (PAHs) has become a serious global issue. Chemical enhancers and strains are often used to remove PAHs from contaminated soil. In this paper, the effects of chemical enhancers, strain HD-1, and Scirpus triqueter in removing pyrene from co-contaminated soil are studied. In the pot experiment, chemical enhancers and HD-1 were added to the co-contaminated soil. On the 60^th day, the plants and soil were taken out for measurement. The result showed that the addition of chemical enhancers and microorganisms (Group PBC) alleviated the inhibition effect of plants on pollution. The accumulation of pyrene in plants of Group PC (chemical enhancers) and Group PBC (chemical enhancers and HD-1) were much higher than those in other groups. Plant enrichment was not the major way to remove pyrene from soil (less than 0.3%). Compared with the contributions of chemical enhancers, HD-1, and Scirpus triqueter, HD-1 had stronger effects on the removal of pyrene (17.23–22.80%). This study indicates that the combination of chemical enhancers, HD-1, and Scirpus triqueter constituted a beneficial composite system, in which the three elements interacted with each other and ultimately achieved the goal of removing pyrene from co-contaminated soil.