Wetland microtopography alters response of potential net CO2 and CH4 production to temperature and moisture: Evidence from a laboratory experiment

•Hummocks had higher potential CO2 and CH4 production than hollows or subsurface peat.•Temperature increased potential CO2 and CH4 production and enzyme activities.•CH4 production occurred primarily under saturated conditions.•Acetoclastic methanogenesis likely dominant CH4 producing pathway.