Articles | Volume 23, issue 21
https://doi.org/10.5194/bg-23-7993-2026
© 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-23-7993-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Nov 2026
Research article |
| 09 Nov 2026
| 09 Nov 2026
Fate of legacy ammonium in the coastal Baltic Sea
Department of Environmental Sciences, University of Helsinki, 00014 Helsinki, Finland
Tvärminne Zoological Station, University of Helsinki, 10900 Hanko, Finland
Marine- and Freshwater Solutions, Finnish Environment Institute, 00790 Helsinki, Finland
Xiaole Sun
CORRESPONDING AUTHOR
School of Marine Sciences, Sun Yat-sen University, 519082 Zhuhai, China
Baltic Sea Centre, Stockholm University, 10691 Stockholm, Sweden
Tom Jilbert
Tvärminne Zoological Station, University of Helsinki, 10900 Hanko, Finland
Department of Geosciences and Geography, University of Helsinki, 00014 Helsinki, Finland
Eva Ehrnsten
Baltic Sea Centre, Stockholm University, 10691 Stockholm, Sweden
Zoological Institute and Museum, University of Greifswald, 17489 Greifswald, Germany
now at: Baltic Sea Centre, Stockholm University, 10691 Stockholm, Sweden
Bo Gustafsson
Baltic Sea Centre, Stockholm University, 10691 Stockholm, Sweden
Lora Harris
Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, 20688 Solomons, MD, USA
Christoph Humborg
Baltic Sea Centre, Stockholm University, 10691 Stockholm, Sweden
Bärbel Müller-Karulis
Baltic Sea Centre, Stockholm University, 10691 Stockholm, Sweden
Alf Norkko
Tvärminne Zoological Station, University of Helsinki, 10900 Hanko, Finland
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Inda Brinkmann, Christine Barras, Tom Jilbert, Tomas Næraa, K. Mareike Paul, Magali Schweizer, and Helena L. Filipsson
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Karol Kuliński, Gregor Rehder, Eero Asmala, Alena Bartosova, Jacob Carstensen, Bo Gustafsson, Per O. J. Hall, Christoph Humborg, Tom Jilbert, Klaus Jürgens, H. E. Markus Meier, Bärbel Müller-Karulis, Michael Naumann, Jørgen E. Olesen, Oleg Savchuk, Andreas Schramm, Caroline P. Slomp, Mikhail Sofiev, Anna Sobek, Beata Szymczycha, and Emma Undeman
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Based on the Baltic Earth Assessment Reports of this thematic issue in Earth System Dynamics and recent peer-reviewed literature, current knowledge about the effects of global warming on past and future changes in the climate of the Baltic Sea region is summarised and assessed. The study is an update of the Second Assessment of Climate Change (BACC II) published in 2015 and focuses on the atmosphere, land, cryosphere, ocean, sediments, and the terrestrial and marine biosphere.
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Short summary
Using model-simulations and field data, we assess the effect of past eutrophication on present and future ammonium dynamics in coastal sediments of the Baltic Sea. Our results indicate a persistent but mild eutrophication legacy effect on sediment-water ammonium release, which is stronger driven by external organic matter loading. The results highlight that external organic matter loading needs to be reduced to also reduce ammonium loading to the coastal ecosystem and enable ecosystem recovery.
Using model-simulations and field data, we assess the effect of past eutrophication on present...
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