Bacterial community succession in dairy manure composting with static composting technique.

This study applied high throughput sequencing technology and phylogenetic investigation of communities by reconstruction of unobserved state (PICRUSt) to examine the microbial population dynamics during the composting of dairy manure and rice straw in a static (without turning) composting system. The results showed that the composition of bacterial community varied significantly during the composting process. The dominant phyla included Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria and Chloroflexi. Biodiversity indices showed that bacterial community diversity had the peak value during the mesophilic phase. Redundancy analysis (RDA) indicated that nitrogen was the most important factors in the distribution of genera during the composting process. Finally, the Pearson correlation results suggested that Thermomonospora and Thermopolyspora could be the biomarkers of the composting maturation phase. The metabolic characteristics of the bacterial communities were predicted by PICRUSt. The result showed that amino acid, lipid metabolism and most of the carbohydrate metabolism increased during the whole composting treatment. However, methane metabolism, carbon fixation pathways in prokaryotes and nucleotide metabolism decreased after the thermophilic phase. The present study provides a better understanding for bacterial community composition and function succession in dairy manure composting.