To explore the contributions of functional bacterial community in composting, we performed medium-scale composting of sewage sludge and sawdust mixtures amended with rice straw biochar at different dosages (5, 10, and 20% of fresh mixture weight) in 400 L bioreactor systems. The dynamics of enzyme activity and bacterial community composition were monitored during the composting. The addition of biochar above 10% inhibited the activity of protease but promoted the activities of cellulase and peroxidase, which also increased the fluctuation of bacterial diversity during the composting. The relationship between the activity of most enzymes and bacterial community was strengthened by the addition of biochar (10% and 20%), which further enhanced the contributions of the functional bacterial communities to composting. Therefore, the study provides evidence for the promoting effects of biochar on the functions of bacterial community.

为了探索功能性细菌群落对堆肥的贡献，我们在400 L生物反应器系统中对污水污泥和锯末混合物进行了中等规模的堆肥处理，并用稻草生物炭进行了不同剂量（新鲜混合物重量的5％，10％和20％）的修正。在堆肥过程中监测酶活性和细菌群落组成的动态。超过10％的生物炭的添加抑制了蛋白酶的活性，但促进了纤维素酶和过氧化物酶的活性，这也增加了堆肥过程中细菌多样性的波动。通过添加生物炭（10％和20％）加强了大多数酶的活性与细菌群落之间的关系，这进一步增强了功能性细菌群落对堆肥的贡献。所以，