Achim Schmalenberger

Introduction:

Via acidic rain, sulfur components had been accumulated in forest soils of the Lehstenbach catchment in the Fichtelgebirge

Previous investigations revealed a potential reduction of sulfate in the upper 10 cm of an acidic fen (Schlöppnerbrunnen I) and the occurrence of sulfate reducing bacteria

Pure culture studies revealed the ability of some sulfate reducers I: to resist oxidative stress, II: to respire oxygen, III: to increase biomass

Since sphagnum moss may introduce oxygen into the upper layers of peat bog by photosynthesis, some of the sulfate reducers in the peat bog might be able to reduce sulfate under oxic conditions

Hypotheses:

The release of oxygen during the daytime by Sphagnum mosses affects the gradients of O₂, H₂S, pH, and SO₄ in the upper 0-5 cm of the peat bog

Biogeochemical gradients in the upper zone affect the microbial community structures

Gene expression of the Dissimilatory bisulfite reductase (DSR) is influenced by diurnal changes and the vertical gradient of oxygen in peat bog

Some sulfate reducers synthesize mRNA from the dsr AB genes in the presence of oxygen to reduce sulfate