Articles | Volume 23, issue 12
https://doi.org/10.5194/bg-23-4057-2026
© Author(s) 2026. 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-23-4057-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
22 Jun 2026
Research article |
| 22 Jun 2026
| 22 Jun 2026
DOM consumption and demethylation of MeHg as potential drivers of low MeHg in Mediterranean Sea sponges and benthic fish: a modeling perspective
David J. Amptmeijer
CORRESPONDING AUTHOR
Matter Transport and Ecosystem Dynamics, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Ulrike Hanz
Benthic Ecology, Alfred Wegener Institute, Am Alten Hafen 26, 27568 Bremerhaven, Germany
Corinna Schrum
Matter Transport and Ecosystem Dynamics, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Universität Hamburg, Institute for Marine Sciences, Mittelweg 177, 20146 Hamburg, Germany
Johannes Bieser
Matter Transport and Ecosystem Dynamics, Helmholtz-Zentrum Hereon, Geesthacht, Germany
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Short summary
Sponges have unusually low methylmercury (MeHg) and high inorganic mercury (iHg) bioaccumulation compared to other macrobenthos. This pattern has been attributed to MeHg demethylation by symbiotic bacteria. Our model demonstrates an alternative explanation that dissolved organic matter (DOM) consumption by sponges can increase iHg and decrease MeHg levels. Low MeHg in sponges at the food web base may further limit MeHg bioaccumulation in higher trophic levels.
Sponges have unusually low methylmercury (MeHg) and high inorganic mercury (iHg) bioaccumulation...
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