Articles | Volume 22, issue 21
https://doi.org/10.5194/bg-22-6727-2025
© Author(s) 2025. 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-22-6727-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
13 Nov 2025
Research article |
| 13 Nov 2025
| 13 Nov 2025
Reduction of carbon, alkalinity and nutrient fluxes in the southern Baltic Sea caused by dragging of otter trawl nets across the seafloor
Pankan Linsy
CORRESPONDING AUTHOR
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany
Stefan Sommer
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany
Jens Kallmeyer
GFZ Helmholtz Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany
Simone Bernsee
GFZ Helmholtz Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany
Florian Scholz
Institute for Geology, Center for Earth System Research and Sustainability, Universität Hamburg, Hamburg, Germany
Habeeb Thanveer Kalapurakkal
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany
now at: Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany
Andrew W. Dale
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany
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Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-146, https://doi.org/10.5194/essd-2025-146, 2025
Revised manuscript accepted for ESSD
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Phosphorus is an essential element for life and its cycling strongly impact primary production. Here, we present a dataset of sediment-water fluxes of dissolved inorganic phosphorus from the Baltic Sea, an area with a long history of eutrophication. The fluxes were measured in situ with three types of benthic chamber landers at 59 stations over 20 years. The data show clear spatial patterns and will be important for marine management and studies on mechanisms in benthic phosphorus cycling.
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Ocean-alkalinity-enhancement technologies refer to various methods and approaches aimed at increasing the alkalinity of seawater. This chapter explores technologies for increasing ocean alkalinity, including electrochemical-based approaches, ocean liming, accelerated weathering of limestone, hydrated carbonate addition, and coastal enhanced weathering, and suggests best practices in research and development.
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Steffen Kutterolf, Mark Brenner, Robert A. Dull, Armin Freundt, Jens Kallmeyer, Sebastian Krastel, Sergei Katsev, Elodie Lebas, Axel Meyer, Liseth Pérez, Juanita Rausch, Armando Saballos, Antje Schwalb, and Wilfried Strauch
Sci. Dril., 32, 73–84, https://doi.org/10.5194/sd-32-73-2023, https://doi.org/10.5194/sd-32-73-2023, 2023
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Tomáš Fischer, Pavla Hrubcová, Torsten Dahm, Heiko Woith, Tomáš Vylita, Matthias Ohrnberger, Josef Vlček, Josef Horálek, Petr Dědeček, Martin Zimmer, Martin P. Lipus, Simona Pierdominici, Jens Kallmeyer, Frank Krüger, Katrin Hannemann, Michael Korn, Horst Kämpf, Thomas Reinsch, Jakub Klicpera, Daniel Vollmer, and Kyriaki Daskalopoulou
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The newly established geodynamic laboratory aims to develop modern, comprehensive, multiparameter observations at depth for studying earthquake swarms, crustal fluid flow, mantle-derived fluid degassing and processes of the deep biosphere. It is located in the West Bohemia–Vogtland (western Eger Rift) geodynamic region and comprises a set of five shallow boreholes with high-frequency 3-D seismic arrays as well as continuous real-time fluid monitoring at depth and the study of the deep biosphere.
Henning Lorenz, Jan-Erik Rosberg, Christopher Juhlin, Iwona Klonowska, Rodolphe Lescoutre, George Westmeijer, Bjarne S. G. Almqvist, Mark Anderson, Stefan Bertilsson, Mark Dopson, Jens Kallmeyer, Jochem Kück, Oliver Lehnert, Luca Menegon, Christophe Pascal, Simon Rejkjær, and Nick N. W. Roberts
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Gerd Krahmann, Damian L. Arévalo-Martínez, Andrew W. Dale, Marcus Dengler, Anja Engel, Nicolaas Glock, Patricia Grasse, Johannes Hahn, Helena Hauss, Mark Hopwood, Rainer Kiko, Alexandra Loginova, Carolin R. Löscher, Marie Maßmig, Alexandra-Sophie Roy, Renato Salvatteci, Stefan Sommer, Toste Tanhua, and Hela Mehrtens
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2020-308, https://doi.org/10.5194/essd-2020-308, 2021
Preprint withdrawn
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The project "Climate-Biogeochemistry Interactions in the Tropical Ocean" (SFB 754) was a multidisciplinary research project active from 2008 to 2019 aimed at a better understanding of the coupling between the tropical climate and ocean circulation and the ocean's oxygen and nutrient balance. On 34 research cruises, mainly in the Southeast Tropical Pacific and the Northeast Tropical Atlantic, 1071 physical, chemical and biological data sets were collected.
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Short summary
Bottom trawling is a fishing method that disturbs the seafloor and affects marine ecosystems. This study conducted experimental trawling and monitored biogeochemical changes over three weeks. Results showed reduced nutrient and alkalinity fluxes, decreased benthic carbon respiration, and disrupted biogeochemical processes. While the decline in alkalinity had only a minor effect on atmospheric CO2, the study highlights the lasting ecological impacts of bottom trawling.
Bottom trawling is a fishing method that disturbs the seafloor and affects marine ecosystems....
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