Linlin Cai, Shuang Pang, Dan Hao, Xiangyang Sun, Ximei Zhang, Muhammad Atif Muneer, Honghui Wu
Co-vermicomposting high-lignin green waste with cattle manure can improve nutrient supply and microbial activity; however, this technology remains limited in terms of lignocellulose degradation efficiency and product quality improvement. This study evaluated the effects of 5% calcium superphosphate (SSP), 5% synthetic lignocellulose-degrading microbial communities (SynComs), and their combined addition on vermicompost quality, microbial communities, and the functional potential related to carbohydrate degradation and nitrogen cycling. The results showed that all treatments maintained a neutral to slightly alkaline pH, favoring the growth of microorganisms involved in carbon and nitrogen cycling. Compared with other treatments, 5% SynComs showed the strongest stimulatory effect on lignocellulose-degrading enzyme and urease activities, effectively reduced the C/N ratio, and increased the germination index, humic substance content, nitrate nitrogen content, and overall quality score. Microbial analysis showed that the amendment treatments enriched nitrogen cycling related taxa, including Luteimonas and Pseudomonas. SynComs further increased the abundances of carbohydrate esterases and glycosyltransferases, as well as the relative abundance of the nitrification gene hao, thereby enhancing the potential for lignocellulose degradation, degradation product transformation, and nitrification. In contrast, SSP alone or combined with SynComs showed limited improvement in the activities and functional potential of enzymes related to carbohydrate and nitrogen metabolism. Overall, lignocellulose-degrading SynComs effectively accelerated co-vermicomposting maturity, improved product quality, and promoted green waste resource utilization. Future studies should optimize aeration conditions to reduce local anaerobic microenvironment formation and denitrification derived N2O emissions.