Performance Analysis and Microbial Community Evolution of In Situ Biological Biogas Upgrading with Increasing H₂/CO₂ Ratio

Figure 1

Methane rate produced by R1 and R2 reactors during the experiment; arrows indicate DNA extraction sampling points: labels include the name of the reactor sampled (R1 or R2), the experimental period in roman letters, and when needed, a letter to distinguish samples from the same reactor and period (a, b, or c).