Metabolic stratification driven by surface and subsurface interactions in a terrestrial mud volcano

摘要: Terrestrial mud volcanism represents the prominent surface geological feature, where fluids and hydrocarbons are discharged along deeply rooted structures in tectonically active regimes. volcanoes (MVs) directly emit major gas phase, methane, into atmosphere, making them important sources of greenhouse gases over time. Quantification methane emission would require detailed insights capacity efficiency microbial metabolisms either consuming or producing subsurface, establishment linkage between these methane-related other abiotic processes. Here we conducted geochemical, microbiological genetic analyses sediments, gases, pore to characterize fluid processes, community assemblages, functions activities a methane-emitting MV southwestern Taiwan. Multiple lines evidence suggest that aerobic/anaerobic oxidation, sulfate reduction methanogenesis compartmentalized discrete, stratified niches, resembling those marine settings. Surface evaporation oxidation sulfide minerals required account for enhanced levels fuels subsurface anaerobic methanotrophy. Methane flux generated by situ appears alter isotopic compositions abundances thermogenic migrating from deep sources, exceed consumption. This metabolic stratification is sustained chemical disequilibria induced mixing upward, anoxic, methane-rich downward, oxic, sulfate-rich fluids.