Methane production rates can be predicted from anaerobic digester microbial community structure

Correlation between bacterial community descriptors and anaerobic digester methane production was investigated for 50 lab-scale anaerobic digesters seeded with different biomass obtained from across the US. Digesters were operated for a minimum of 60 days to attain quasi-steady state and fed a readily degradable synthetic dairy wastewater. Although digesters were operated identically, their quasi steady state biogas methane production varied over an order of magnitude. Step-wise multiple linear regression was used to correlate the high throughput Illumina-Miseq bacterial community data and digester methane production rate. A preliminary model was developed which included 10 bacterial OTUs. This study demonstrates that a quantitative, predictive model relating digester performance to microbial community descriptors is possible.