Microbial co-occurrence networks driven by low-abundance microbial taxa during composting dominate lignocellulose degradation

Lignocellulose, which contains cellulose, hemicellulose and lignin, is one of the most important factors determining the rate and quality of compost decomposition, and the microbial community composition affects the rate of lignocellulose decomposition. Interactions between microbial taxa contribute significantly to ecosystem energy flow and material cycling. However, it is not clear how interactions between microbial taxa affect the degradation of lignocellulose during the composting process. For this reason we carried out aerobic co-composting experiments with maize straw and cattle manure to explore the contribution of microbial community diversity and the interaction between taxa to lignocellulosic degradation. The results showed that moisture and temperature had the greatest effect on microbial communities during composting and that lignocellulose degradation was dominated by microbial co-occurrence networks rather than microbial community diversity. Overall co-occurrence network and bacterial-fungal interactions explained 23.9-84.1 % of lignocellulosic degradation, whereas microbial diversity only accounted for 24.6-31.5 %. Interestingly, keystone taxa analysis of the microbial cooccurrence networks revealed that low-abundance taxa influenced microbial interactions driving lignocellulose degradation. Our results provide a new perspective for understanding lignocellulose degradation during composting, offering insights into important microbial interaction mechanisms for improving compost quality and efficiency.

Automated summary

This study investigated the impact of interactions between microbial taxa on lignocellulose degradation during composting. The results showed that co-occurrence networks and bacterial-fungal interactions played significant roles in lignocellulose degradation, while microbial diversity had a relatively minor effect. Moreover, low-abundance taxa were found to influence microbial interactions driving lignocellulose degradation.