Assessing the Performance and the Microbial Dynamics of Co-composting System Using Recycled Cow Manure and Bedding Material Waste 

Abstract

Co-composting of recycled cow manure and waste bedding material has been used to convert both agricultural wastes to biofertilizers. This study explored the succession of microbial community, metabolic function and substances conversion capacities during 60 days’ co-composting using high throughput sequencing technology. The study revealed that co-composting of cow manure and bedding material waste at a ratio of 1.32 (CM+B) had the highest efficiency among four treatments. The bacterial and fungal community diversity changed significantly during the co-composting of CM+B group, and the major phyla included Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria and Ascomycota. PICRUSt and FUNGuild analysis showed that carbohydrate, lipid metabolism and especially nitrogen fixation were enhanced in the thermophilic phase, while animal and plant pathogens were not detected after the co-composting. Wood saprotrophs became the dominant fungal group (89.1%) in the maturation phase. Canonical correlation analysis (CCA) and redundancy analysis (RDA) confirmed that temperature influenced bacterial community succession more than it influenced fungal community succession. Ruminiclostridium had a significantly positive relationship with temperature (p_value < 0.05), while pH and C/N had significant effect on the fungal (p_value < 0.05), and Penicillium and Mortierella were significantly related to moisture (p_value < 0.05). This work describes an efficient methodology to deal with co-composting systems that had been successfully applied in agricultural wastes treatment, enabling further understanding in mechanisms underlying the substance conversion and the involved microbial community succession in sophisticated composting system.