FIG 1.
Experimental design for culture-dependent and independent description of methylotrophic methanogenesis in wetland soils. A soil core from a plant-covered wetland site was subsectioned by depth. The 0- to 5-cm and 24- to 35-cm sections were used for 1H NMR identification of porewater metabolites and for shotgun metatranscriptomic sequencing. Triplicate soil microcosms were either amended with TMA or unamended (endogenous controls). Methane production and microbial community composition were characterized approximately weekly over 24 days as indicated by arrows along the timeline. TMA was added at time points 0 to 3 to reach the in-tube concentrations shown.