Articles | Volume 23, issue 12
https://doi.org/10.5194/bg-23-4145-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/bg-23-4145-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
23 Jun 2026
Research article |
| 23 Jun 2026
| 23 Jun 2026
Biochemical characteristics of the sea surface microlayer in the central Baltic Sea and potential signatures of cyanobacterial blooms
Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, 24148, Germany
Theresa Barthelmeß
Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, 24148, Germany
Bita Sabbaghzadeh
Leibniz Institute for Baltic Sea Research, Warnemünde, Germany
Anja Engel
Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, 24148, Germany
Christian Albrechts University of Kiel, Kiel, Germany
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Biogeosciences, 23, 1261–1278, https://doi.org/10.5194/bg-23-1261-2026, https://doi.org/10.5194/bg-23-1261-2026, 2026
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Preprint archived
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Theresa Barthelmeß and Anja Engel
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France Van Wambeke, Vincent Taillandier, Karine Desboeufs, Elvira Pulido-Villena, Julie Dinasquet, Anja Engel, Emilio Marañón, Céline Ridame, and Cécile Guieu
Biogeosciences, 18, 5699–5717, https://doi.org/10.5194/bg-18-5699-2021, https://doi.org/10.5194/bg-18-5699-2021, 2021
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Simultaneous in situ measurements of (dry and wet) atmospheric deposition and biogeochemical stocks and fluxes in the sunlit waters of the open Mediterranean Sea revealed complex physical and biological processes occurring within the mixed layer. Nitrogen (N) budgets were computed to compare the sources and sinks of N in the mixed layer. The transitory effect observed after a wet dust deposition impacted the microbial food web down to the deep chlorophyll maximum.
Frédéric Gazeau, France Van Wambeke, Emilio Marañón, Maria Pérez-Lorenzo, Samir Alliouane, Christian Stolpe, Thierry Blasco, Nathalie Leblond, Birthe Zäncker, Anja Engel, Barbara Marie, Julie Dinasquet, and Cécile Guieu
Biogeosciences, 18, 5423–5446, https://doi.org/10.5194/bg-18-5423-2021, https://doi.org/10.5194/bg-18-5423-2021, 2021
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Our study shows that the impact of dust deposition on primary production depends on the initial composition and metabolic state of the tested community and is constrained by the amount of nutrients added, to sustain both the fast response of heterotrophic prokaryotes and the delayed one of phytoplankton. Under future environmental conditions, heterotrophic metabolism will be more impacted than primary production, therefore reducing the capacity of surface waters to sequester anthropogenic CO2.
Evelyn Freney, Karine Sellegri, Alessia Nicosia, Leah R. Williams, Matteo Rinaldi, Jonathan T. Trueblood, André S. H. Prévôt, Melilotus Thyssen, Gérald Grégori, Nils Haëntjens, Julie Dinasquet, Ingrid Obernosterer, France Van Wambeke, Anja Engel, Birthe Zäncker, Karine Desboeufs, Eija Asmi, Hilkka Timonen, and Cécile Guieu
Atmos. Chem. Phys., 21, 10625–10641, https://doi.org/10.5194/acp-21-10625-2021, https://doi.org/10.5194/acp-21-10625-2021, 2021
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In this work, we present observations of the organic aerosol content in primary sea spray aerosols (SSAs) continuously generated along a 5-week cruise in the Mediterranean. This information is combined with seawater biogeochemical properties also measured continuously along the ship track to develop a number of parametrizations that can be used in models to determine SSA organic content in oligotrophic waters that represent 60 % of the oceans from commonly measured seawater variables.
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Short summary
Cyanobacteria form massive summer blooms in the Baltic Sea that release organic compounds to the ocean’s surface. By analyzing the thin boundary layer between ocean and atmosphere, this study shows that cyanobacteria influence the molecular composition and surface properties of the sea surface, increasing surfactants that may reduce gas exchange. The findings provide new insight into how future cyanobacteria blooms could affect air-sea interactions and climate-related processes.
Cyanobacteria form massive summer blooms in the Baltic Sea that release organic compounds to the...
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