Microbial Community Structure and Predicted Bacterial Metabolism Function in Biochar Pellets Aged in Soil after 34 Months.

In the present study, The structure of soil microbiome in biochar pellets aged in soil over 34 months was evaluated by using 454 pyrosequencing, and the activities of bacteria and fungi were compared by measuring their biomarkers. Biochar pellets were analyzed by pyrolysis-gas chromatography/mass spectroscopy during 34 months aging. The metabolic functions of the bacterial community were predicted by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt). The structure of bacterial community was greatly shifted in biochar pellets in comparison with their fungal counterpart. The overall bacterial activity outweighs that in fungi. The composition of pyrolysates in biochar pellets was changed during 34 months aging, which may infer the slow breakdown of intermediate labile organic carbons in biochar. PICRUSt indicated the decreased capacity in metabolizing carbohydrates and increased capacity in utilizing xenobiotics. The higher concentration of WSC occurred in biochar pellets further supported the prediction.