Enhancing nitrogen transformation and humification in cow manure composting through psychrophilic and thermophilic nitrifying bacterial consortium inoculation

[Display omitted] •A cryolithophilic thermophilic nitrifying bacterial consortium (CNB) was developed.•CNB enhanced nitrite oxidoreductase’s activity and elevated nxrA gene abundance.•CNB inoculation reduced NH3 and N2O emissions and increased the humus content.•CNB inoculation of compost is environmentally friendly and cost-effective. Excessive nitrogen release during composting poses significant challenges to both the environment and compost quality. Biological enhancement of humification and nitrogen conservation is an environmentally friendly and cost-effective approach to composting. The aim of this study was to develop a psychrophilic and thermophilic nitrifying bacterial consortium (CNB) and investigate its role in nitrogen transformation and humification during cow manure composting. Analysis revealed that CNB inoculation promoted microbial proliferation and metabolism, significantly increased the number of nitrifying bacteria (p