An ex situ fermentation system (EFS) can efficiently transform and utilize nitrogen in swine wastewater and reduce environmental pollution. High-throughput sequencing was used to study the relationship between the succession of total bacteria, fungi, and functional bacteria in a swine wastewater EFS, as well as nitrogen metabolism and environmental factors. During the fermentation process, inorganic nitrogen gradually accumulated and the pH changed rapidly from weakly acidic to alkaline. The dominant genera of bacteria, fungi and functional bacteria carrying amoA, nirK, and nosZ genes changed gradually, and Clostridium sensu stricto 1, Thermomyces, Nitrosomonas, Mesorhizobium, and Pseudomonas genera became the most abundant, which showed positive correlations with temperature, pH, and nitrogen levels. Other changed populations showed different correlations with environmental factors, and physical-chemical factors explained more variation of microorganisms than nitrogen resources. These findings contribute to a comprehensive understanding of nitrogen metabolism in EFSs from a molecular micro-ecology perspective.
Keywords: Bacterial community; Ex situ fermentation system; Functional bacterial community; Fungal community; Nitrogen metabolism.
Copyright © 2021 Elsevier B.V. All rights reserved.