Succession of bacterial community function in cow manure composing

Succession of bacterial community, metabolism function and substrate utilization capacity in 60 days composting of cow manure were analyzed by 16S rRNA pyrosequencing, PICRUSt and Biolog method, respectively. The results showed that the number of bacterial OTUs increased from 176 in raw cow manure to 203 on Day-10, 220 on Day-30 and 313 on Day-60 of the composting, respectively. The PICRUSt analysis showed that the relative abundances of genes involved in lipid and carbohydrate metabolism increased by 28.5% and 22.4% during the incubation, respectively, but the abundances of the genes involved in nucleotide and amino acid metabolism decreased by 21.6% and 2.1%. Furthermore, the average well color development (AWCD) of carboxylic acids (0.99-0.48) and amino acids (1.61-0.89) in Biolog Eco-microplate displayed a steady downtrend through the composting process. Redundancy analysis showed that ORP, moisture and temperature could explain 68.1%, 17.6% and 14.2% of the variation in bacterial genera, respectively.