Anna Karenina ecological principle in biogas research. Biogass plant

Process monitoring and control is very important issue in case of biogas plants utilizing fluctuating quality substrates including feedstock with potential inhibitory effects. As an example, anaerobic digestion of protein or urea-rich feedstock is often associated with ammonia inhibition, which affects the microbial community structures. Appearance of certain indicator species is considered to be used as a warning signal of process failure. However, according to the Anna Karenina ecological principle (AKP) certain stressors have stochastic rather than deterministic effects on microbial community compositions. The aim of this study was the investigation of the validity of AKP in biogas reactors experiencing ammonia inhibition.