Effects of Exogenous Inoculation on Microbial Community Dynamics and Maturation Process in Cattle Manure Composting

Cattle manure composting is an effective strategy for recycling agricultural waste. However, the presence of lignocellulosic materials in cattle manure-maize straw mixtures can limit the degradation efficiency during composting. This study investigated the effects of microbial inoculation on composting performance using three treatments: a lignocellulose-degrading microbial consortium (MC1), a commercial microbial inoculant (BS1), and a non-inoculated control (CK). The results showed that the MC1-treated pile entered the thermophilic phase (>50 °C) earlier than the BS1-treated pile. After 49 days of composting, the lignocellulose degradation rates in the MC1, BS1, and CK treatments were 46.25%, 37.5%, and 29.8%, respectively. Based on compost maturity indicators, including temperature, C/N ratio, pH, and electrical conductivity (EC), the composting period required to reach maturity was shortened by 8 days in the MC1 treatment compared with the BS1 treatment (37 vs. 45 days). Microbial community analysis indicated that MC1 inoculation increased the relative abundance of key microbial groups, particularly Ascomycota and Firmicutes, thereby enhancing lignocellulose degradation and accelerating composting. These findings provide insights into the application of lignocellulose-degrading microbial inoculants for improving cattle manure composting efficiency.