Impact of pine leaf biochar amendment on bacterial dynamics and correlation of environmental factors during pig manure composting.

The influence of pine leaf biochar (PLB) amendment on bacterial community succession and its correlation with physic-chemical parameters during pig manure (PM) composting was evaluated. The five different dosages of PLB [at 0% (T1), 2.5% (T2), 5% (T3), 10% (T4) and 15% (T5)] mixed with initial composting mass were conducted to composting for 50 days. The present study indicated that bacterial diversity was significantly (p < 0.05) higher in PLB amended treatments than the control, but T4 treatment showed the highest among the all PLB applied treatment. Firmicutes, Actinobacteria, Proteobacteria and Bacteroidete were four most abundant phyla of all the treatments. Furthermore, redundancy analysis showed that the bacterial community were significantly (p < 0.05) positively correlated with temperature, pH, TOC, CO2 and NH3 emissions, while they were negatively correlated with the N2O and CH4 emission. Overall, the results suggested that the addition of 10% PLB (T4 treatment) was a potential option to enhance the composting efficiency with significantly greater abundance of bacterial community and finally improved the compost quality.