Immobilized microbial reduce nitrogen loss during composting: Enhancement of ammonia assimilation and nitrification...

To address the challenge of substantial nitrogen loss in the form of ammonia volatilization (with a peak NH₄⁺-N concentration of 10.21 mg/g in the control group, CK) during livestock and poultry manure composting, which significantly reduces fertilizer efficacy, this study innovatively employed sodium alginate encapsulation technology to construct protective "microcapsules' for functional microorganisms prior to their introduction into the aerobic composting environment. These encapsulated microorganisms exhibited markedly improved survival rates under harsh conditions and continuously and efficiently promoted both nitrification and ammonia assimilation. The experimental results showed that the immobilized bacterial preparation reduced ammonia emissions by 36.52 % and total nitrogen loss by 33.20 %, demonstrating significantly better performance than traditional bacterial preparations. This modification offers a modest improvement to the process flow. Additionally, its recyclable feature facilitates resource recovery and cost optimization, thereby offering innovative and practical technical support for the green transformation of the composting industry.