Parameters of microbiological processes of organic matter destruction in bottom sediments from the Baltic Sea

Microbiological processes of organic matter (OM) destruction in bottom sediments of the Baltic Sea in the winter period (January-February) of 1995 were investigated. Daily rates of some processes reached were as follow: total destruction of OM was 10-130 mg C/m2 absorption of O2 was 0-59 mg/m2, release of CO2 was 18-120 mg C/m2, assimilation of CO2 was 2.6-36 mg C/m2, sulfate reduction was 2.7-90 mg S/m2, methanogenesis was 0.06-5.4 ml CH4/m2, and aerobic methane oxidation was 0-4.3 ml CH4/m**2. It was found that the major part of OM in the sediments was destroyed anaerobically. As this occurred, reduced products of decay were incorporated into bacterial metabolism. In winter products of chemosynthesis and methane compensated for deficiency of OM photosynthesis in the ecosystem.