Efficiency of Phytoremediation on the Sediments Co-contaminated by Heavy Metals and Organic Compounds and the Role of Microbes in the Remediation System

This paper presents the findings of a one-year research project, in which participants explored the function of microbe remediation efficiency and plant growth. Corn and rye grass were planted separately and in mixed quantities to remediate sediments co-contaminated by heavy metals and typical polycyclic aromatic hydrocarbons (PAHs). The study revealed that both the number and the activity of microbes were affected during the sediment remediation process. It also showed that the overall trend at first increased and then decreased, with the microbial numbers reaching their highest levels during the second week of soil cultivation. In the heavy-metal, organic-compound, co-contaminated matrix, the researchers found that mono-cropping the corn removed more lead, with the removal rate reaching a high of 12.96%. They found further that in the mixed-planting pattern, the removal rate of zinc reached a maximum level of 31.4%. The results of the study showed conclusive evidence that organic matters play an important role in the plant-microbe remediation of contaminated sediments.