Effects of afforestation on heavy metal pollutants and responses of soil microbial community

Artificial afforestation may be the most effective method to remediate the heavy metal contaminated soil. However, different plants have different effect for remediating different metals in contaminated soils. In our study, we detected 8 type of sites with high contents of heavy metals, covered by different plants, determined the soil characteristics (pH, Cu, Zn, Cr and Cd et al.) and soil microorganisms using high throughput sequencing, in order to elaborate effects of different planting trees on the level of heavy metals and how response of microbial community after remediation. As a result, we concluded that Cr and Cd were the main factors that changed microbial communities in polluted soil. And the composition and structure of microbial community were changed significantly after planting different trees. Simultaneously, several function of microbial community, including cycle and metabolism, declined after forest established by artificial plantation. The relative abundance of Acidobacteria increased after plantation and Actinobacteria maintained a quite low level in these polluted soils than other normal soils. In fungal community, two major phyla in these 24 samples are Ascomycota and Basidiomycota. Apart from that, Phyllostachys heterocycla plantation may the best method of heavy-metal remediation as it can accumulate high content of Zn, Cr, Ni etc.