Synergistic effects of biochar and cellulase on carbon emission reduction and humification during co-composting of cattle manure and sugarcane bagasse

Introduction: The emission of carbon dioxide (CO₂) and methane (CH₄) during composting not only contributes to the greenhouse effect but also leads to carbon loss, thereby reducing humus production and compromising the quality of the final compost product. This study investigated the efficacy and underlying mechanisms of biochar and cellulase addition, individually and in combination, in mitigating emissions and enhancing compost quality within a cattle manure-sugarcane bagasse co-composting system. Methods: By monitoring key composting parameters and combining with high-throughput sequencing analysis of bacterial and fungal communities, the changes of microbial structure and function were evaluated, focusing on organic carbon transformation, humification pathway and greenhouse gas mitigation mechanism. Results and discussion: ), thereby directing a greater carbon flux toward humification pathways. This study confirms that the synergy between biochar and cellulase effectively mitigates greenhouse gas emissions and improves the quality of compost, providing a theoretical basis for developing low-carbon, high-value composting technologies.