A carbon budget for a eutrophic marine ecosystem and the role of sulfur metabolism in sedimentary carbon, oxygen and energy dynamics

Abstract

Organic carbon was budgeted for an experimental marine ecosystem which received 21.2 mol C m-2 of allochthonous sewage sludge plus 12.4 mol C m-2 in situ net daytime production over a 99 day experiment. The fate of carbon, in order of importance, was remineralization, storage in the sediments and export. Sediment carbon metabolism was dominated by sulfate reduction which resulted in the dissociation of organic carbon remineralization from oxygen consumption and energy cycling. The sediments were inefficient in processing sedimented carbon and its associated chemical energy. -from Authors