Articles | Volume 19, issue 16
https://doi.org/10.5194/bg-19-3775-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-19-3775-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Aug 2022
Research article |
| 19 Aug 2022
| 19 Aug 2022
Benthic alkalinity fluxes from coastal sediments of the Baltic and North seas: comparing approaches and identifying knowledge gaps
Bryce Van Dam
CORRESPONDING AUTHOR
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Nele Lehmann
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
Interdisciplinary Faculty, University of Rostock, Rostock, Germany
Mary A. Zeller
Geochemistry & Isotope Biogeochemistry, Leibniz Institute for Baltic Sea Research (IOW), Warnemünde, Germany
Andreas Neumann
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Daniel Pröfrock
Institute of Coastal Environmental Chemistry, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Marko Lipka
Geochemistry & Isotope Biogeochemistry, Leibniz Institute for Baltic Sea Research (IOW), Warnemünde, Germany
Helmuth Thomas
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
Michael Ernst Böttcher
Geochemistry & Isotope Biogeochemistry, Leibniz Institute for Baltic Sea Research (IOW), Warnemünde, Germany
Marine Geochemistry, University of Greifswald, Greifswald, Germany
Interdisciplinary Faculty, University of Rostock, Rostock, Germany
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Short summary
We quantified sediment–water exchange at shallow sites in the North and Baltic seas. We found that porewater irrigation rates in the former were approximately twice as high as previously estimated, likely driven by relatively high bioirrigative activity. In contrast, we found small net fluxes of alkalinity, ranging from −35 µmol m−2 h−1 (uptake) to 53 µmol m−2 h−1 (release). We attribute this to low net denitrification, carbonate mineral (re-)precipitation, and sulfide (re-)oxidation.
We quantified sediment–water exchange at shallow sites in the North and Baltic seas. We found...
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