The role of bacterial grazers in controlling oxic and anoxic decomposition of organic matter
- State Univ. of New York, Stony Brook, NY (United States). Marine Sciences Research Center
One prominent theory describing the relation between productivity, O[sub 2], and carbon preservation is that anoxic decomposition is intrinsically slower than oxic decomposition and thus results in the accumulation of organic matter in anoxic sediments and waters. However, several past studies suggest that differences in the intrinsic rates of decomposition between the two types of systems are small. Measurement of the microbial metabolism of individual radiolabeled compounds in the oxic and anoxic waters of stratified water bodies provides further evidence of this. This lack of a rate difference suggests the need for further explanation of the controls on carbon preservation. One possible explanation is that animal-poor anoxic sediments may sequester organic matter as bacterial biomass or as bacterial-derived products in the absence of bacterial grazers. Thus, differences in the numbers and diversity of organisms that graze upon bacteria between oxic and anoxic sediments may explain part of the difference in carbon preservation rates that have been observed between the two types of systems. The absence of bacterial grazers in compacted sediments could also explain why organic carbon is preserved in deep oxic and ancient sediments.
- OSTI ID:
- 5998322
- Report Number(s):
- CONF-921058--
- Journal Information:
- Geological Society of America, Abstracts with Programs; (United States), Journal Name: Geological Society of America, Abstracts with Programs; (United States) Vol. 24:7; ISSN GAAPBC; ISSN 0016-7592
- Country of Publication:
- United States
- Language:
- English
Similar Records
Role of sedimentary organic matter in bacterial sulfate reduction: the G model tested
Relation between sedimentation rate and burial of organic phosphorus and organic carbon in marine sediments