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

Zhiming Xu; Ronghua Li; Daniel KuoK Ho Tang; Xiu Zhang; Xin Zhang; Hong Liu; Fusheng Quan

doi:10.1016/j.biortech.2024.131507

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

Bioresour Technol. 2024 Sep 18:131507. doi: 10.1016/j.biortech.2024.131507. Online ahead of print.

Authors

Zhiming Xu¹, Ronghua Li², Daniel KuoK Ho Tang³, Xiu Zhang⁴, Xin Zhang⁵, Hong Liu⁶, Fusheng Quan⁷

Affiliations

¹ College of Veterinary Medicine, Northwest A&F University, Key Laboratory of Animal Biotechnology of the Ministry of Agriculture and Rural Affairs, Yangling, Shaanxi 712100, China; School of Natural Resources and Environment, Northwest A&F University (NWAFU), Yangling 712100, Shaanxi, China.
² School of Natural Resources and Environment, Northwest A&F University (NWAFU), Yangling 712100, Shaanxi, China; School of Natural Resources and Environment, NWAFU-UA Micro-campus, Yangling, Shaanxi 712100, China.
³ The University of Arizona (UA), The Department of Environmental Science, Tucson, AZ 85721, USA; School of Natural Resources and Environment, NWAFU-UA Micro-campus, Yangling, Shaanxi 712100, China.
⁴ North Minzu University Ningxia Key Laboratory for the Development and Application of Microbial Resources in Extreme Environments, Yinchuan 750021, China.
⁵ College of Veterinary Medicine, Northwest A&F University, Key Laboratory of Animal Biotechnology of the Ministry of Agriculture and Rural Affairs, Yangling, Shaanxi 712100, China.
⁶ School of Natural Resources and Environment, Northwest A&F University (NWAFU), Yangling 712100, Shaanxi, China.
⁷ College of Veterinary Medicine, Northwest A&F University, Key Laboratory of Animal Biotechnology of the Ministry of Agriculture and Rural Affairs, Yangling, Shaanxi 712100, China. Electronic address: quanfusheng@nwafu.edu.cn.

PMID: 39303947
DOI: 10.1016/j.biortech.2024.131507

Abstract

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 < 0.05), and elevated the activity of nitrite oxidoreductase and nxrA gene abundance. Compared to the control, CNB inoculation promoted the formation of NO₃^--N (77.87-82.35 %), while reducing NH₃ (48.89 %) and N₂O (20.05 %) emissions and increased humus content (16.22 %). Mantel analysis showed that the higher abundance of nitrifying bacteria and nxrA facilitated the nitrification of NH₄⁺-N. The improvement in nitrite oxidoreductase activity promoted NO₃^--N formation, leading to increased humus content and enhanced compost safety.

Keywords: Compost quality; Environmental threats; Humification; Nitrifying bacterial consortium; Nitrogen transformation.