| Autor: |
van de Velde, Sebastiaan J., Hylén, Astrid, Eriksson, Mats, James, Rebecca K., Kononets, Mikhail Y., Robertson, Elizabeth K., Hall, Per O. J. |
| Rok vydání: |
2023 |
| DOI: |
10.6084/m9.figshare.23634853 |
| Popis: |
Organic carbon (OC) burial efficiency, which relates the OC burial rate to respiration in the seafloor, is a critical parameter in the reconstruction of past marine primary productivities. The current accepted theory is that sediments underlying oxygen-deficient (anoxic) bottom waters have low respiration rates and high OC burial efficiencies. By combining novel in situ measurements in anoxic basins with reaction-transport modelling, we demonstrate that sediments underlying anoxic bottom waters have much higher respiration rates than commonly assumed. A major proportion of the carbon respiration is concentrated in the top millimeter—the so-called ‘reactive surface layer’—which is likely a feature in approximately 15% of the coastal seafloor. When re-evaluating previously published data in light of our results, we conclude that the impact of bottom-water anoxia on OC burial efficiencies in marine sediments is small. Consequently, reconstructions of past marine primary productivity in a predominantly anoxic ocean based on OC burial rates might be underestimated by up to an order of magnitude. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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