Comparison of microbial communities in replicated woodchip bioreactors

The microbial community inhabiting woodchip bioreactors is under-investigated at the pilot scale. In this study, our goals were to understand the factors that influence woodchip bioreactor microbial community variation in replicated field bioreactors, investigate the factors that drive microbial community composition, and evaluate relationships between microbial community membership and nitrogen cycling genes. We used a combination of qPCR of nirS, nirK, nosZI, and nosZII and 16S rRNA amplicon sequencing to characterize the microbial communities of nine, pilot-scale woodchip bioreactors located at Iowa State University. Our results showed dynamic microbial communities but with persistent taxa between sampling years and hydraulic retention times (HRTs). Similarities between functional gene copy numbers across sampling year and HRT indicate that the function of denitrification is conserved despite differences in the microbial communities. These results are evidence that the suggest that there are specific and persistent taxa within bioreactors. This microbial membership are recommended to be the focus of future studies to better understand the relationship between microbial functions and denitrification in bioreactor management.These are the SSU amplicon datasets associated with the study.