Hydrogen Dynamics in Cyanobacteria Dominated Microbial Mats Measured by Novel Combined H2/H2S and H2/O2 Microsensors.

摘要: Hydrogen may accumulate to micromolar concentrations in cyanobacterial mat communities from various environments, but the governing factors for this accumulation are poorly described. We used newly developed sensors allowing simultaneous measurement of H2S and H2 or O2 within same point elucidate interactions between oxygen, sulfate reducing bacteria, producing microbes. After onset darkness subsequent change oxic anoxic conditions uppermost ~1 mm mat, accumulated up 40 µmol L-1 formerly layer, with high variability among sites sampling dates. The immediate production after darkening points fermentation as main process mat. measured profiles indicate that a gradual disappearance peak was mainly due activity bacteria invaded surface layer below, persisted an inactive state during illumination. absence significant consumption first ~30 min indicated active reducers period. Addition methanogenesis inhibitor BES led increase H2, indicating methanogens contributed H2. Both formation seemed unaffected by presence/absence H2S.