[BCG06-P01] Dynamisms and characteristics of dissolved organic matter (DOM) in deep aquifer: A scope for deep biosphere
Keywords:HMW-DOM, sterol, carbon and hydrogen isotopic compositions, deep aquifer, methanogenesis
To date, formation of DOM fraction and potential microbial interaction in deep aquifer have been particularly poorly understood on the context of prokaryotic ecology. We investigated the molecular composition of DOM fraction including LMW and HMW by an improved method (Urai et al., 2018). The filtered samples are tentatively defined by conventional size scales; macromolecular scale (100 mm >> 40 mm), POM (40 mm >> 0.6 mm), HMW-DOM(0.6 mm>>1kDa), and total-DOM (<0.6 mm). We also have a validation to distinguish the molecular signature between phototrophic primary producers (i.e., fossil molecules) and presently living benthic prokaryotes (i.e., modern molecules; cf. biological methanogenesis, Kaneko et al., 2014). We report a preliminary result of the feasibility study and discuss a perspective from the view of deep biosphere.
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