Activity and diversity of methane-oxidizing bacteria in glacier forefields on siliceous and calcareous bedrock

Abstract

Abstract. The global methane (CH4) cycle is largely driven by methanogenic archaea and methane-oxidizing bacteria (MOB), but little is known about their activity and diversity in pioneer ecosystems. We conducted a field survey in forefields of 13 receding Swiss glaciers on both siliceous and calcareous bedrock to investigate and quantify CH4 turnover based on soil-gas CH4 concentration profiles, and to characterize MOB communities using pmoA sequencing and T-RFLP. Methane turnover was fundamentally different in the two bedrock categories. Of the 36 CH4 concentration profiles from siliceous locations, 11 showed atmospheric CH4 consumption at concentrations of ∼1–2 μl l−1 with soil-atmosphere ..