pH controls over anaerobic carbon mineralization, the efficiency of methane production, and methanogenic pathways in peatlands across an ombrotrophic-minerotrophic gradient

► Fermentation was the main pathways of anaerobic carbon mineralization. ► pH is a primary factor controlling fermentative activity in peatlands. ► Higher pH increased the efficiency of methane versus carbon dioxide production. ► pH did not affect the dominance of acetoclastic methanogenesis in methane production. ► pH alone was unable to explain low methane productions in ombrotrophic peatlands.