Effects of Inoculation with Newly Isolated Cold-Adapted Bacteria on Winter Cattle Manure Composting in the Tibetan Plateau

The low-temperature environment of the Tibetan Plateau presents a technical challenge to composting. This study screened cold-adapted microbes with strong degradation ability and selected five strains to experimentally test and evaluate composting cattle manure in a natural environment in the plateau region. The results showed that both the control and the treatment groups had a slow temperature rise at the beginning of the composting. However, after the first turning, the temperature rise in the inoculated group accelerated. The inoculation of cold-adapted bacteria increased the OM loss in the compost by 8.6%, decreased the retention of nitrogen of the compost by 3%, and increased the seed germination index (GI) value from 44.4% to 73.9%. Microbial community structure analysis showed that the relative abundance of Psychrobacter was more than 50% at the beginning of the composting in the two experimental groups. The cold-adapted microbial inoculation increased the diversity of the microbial community, i.e., Truepera and Luteimona, and the abundance of specific microorganisms during the thermophilic and maturation stages. This study demonstrates that inoculation of cold-adapted bacteria improves the maturity and efficiency of cattle manure composting in a natural plateau environment.