idw – Informationsdienst Wissenschaft
Nachrichten, Termine, Experten
Nachrichten, Termine, Experten
25 March 2025/Kiel. How is organic matter transported from productive coastal areas to the open ocean? Researchers from the GEOMAR Helmholtz Centre for Ocean Research Kiel and MARUM - Centre for Marine Environmental Sciences at the University of Bremen have now shown that eddies play a crucial role in this process. The swirling currents contain large amounts of energy-rich and essential fat molecules (essential lipids), which play a key role in marine food webs and the carbon cycle. The study has now been published in the journal Communications Earth and Environment.
Mesoscale eddies, oceanic gyres about 100 kilometres in diameter, are ubiquitous features of the global ocean and play a vital role in marine ecosystems. Eddies, which form in biologically productive coastal upwelling regions, are important transporters of carbon and nutrients. These eddies trap water masses and migrate into the open ocean, where productivity is comparatively low. As such, they have a significant influence on the nutrient and carbon cycles within the ocean.
For decades, marine scientists have sought to understand in detail how coastal waters are transported offshore and how this process affects productivity in the open ocean, especially as eddy activity is expected to change significantly due to climate change.
While it was previously known that ocean eddies transport large quantities of organic carbon and nutrients, the exact composition and nutritional quality of this material for zooplankton and fish has remained largely unexplored. Using high-resolution mass spectrometry, a team of researchers from GEOMAR and MARUM has now analysed the lipidome – the totality of fat molecules – in and around an ocean eddy. The results of their work have been published in the journal Communications Earth and Environment.
Cutting-edge analysis reveals lipid diversity in eddies
“These eddies are essentially the food trucks of the ocean,” explains Dr Kevin Becker, geochemist at GEOMAR and lead author of the study. “They transport nutrients from the highly productive coastal upwelling regions to the open ocean, where they are released and are likely to influence biological productivity.”
For their study, the researchers analysed samples collected during the GEOMAR-coordinated REEBUS project (Role of Eddies in the Carbon Pump of Eastern Boundary Upwelling Systems) on the METEOR M156 Expedition off the coast of Mauritania (West Africa). Almost 1,000 different lipids were identified. Lipids can make up to 20 percent of the carbon content of phytoplankton and are essential building blocks of cells, performing critical biological functions as energy stores, membrane components, signalling molecules, and electron transporters.
“Lipids also contain chemotaxonomic information that allows us to determine the composition of microbial communities,” adds Dr Becker. “Based on their chemical signatures, we can distinguish between lipids from phytoplankton, bacteria, and archaea species.”
The results of the study showed that the lipid signature within the gyre was significantly different from that of the surrounding waters, indicating a distinct microbial community. In particular, energy-rich storage lipids and essential fatty acids were enriched – nutrients that higher marine organisms such as zooplankton and fish cannot synthesise on their own and must ingest through food.
Calculations show that coastal eddies in the upwelling region off Mauritania transport up to 9.7 ± 2.0 gigagrams (about 10,000 tonnes) of labile organic carbon to the open ocean each year. “Our study highlights the central role of mesoscale eddies in the local carbon cycle and provides a basis for future investigations of their importance on a global scale,” concludes Prof. Dr Anja Engel, lead scientist of the study and head of the Marine Biogeochemistry Research Division at GEOMAR.
Original Publication:
Becker, K.W., Devresse, Q., Prieto-Mollar, X., Hinrichs, K.U., & Engel, A. Mixed-layer lipidomes suggest offshore transport of energy-rich and essential lipids by cyclonic eddies. Commun Earth Environ 6, 179 (2025).
https://doi.org/10.1038/s43247-025-02152-0
About: REEBUS
The REEBUS project (Role of Eddies in the Carbon Pump of Eastern Boundary Upwelling Systems) was funded by the German Federal Ministry of Education and Research (BMBF, funding code 03F0815A) and coordinated at GEOMAR. The aim of Work Package 4, led by Prof. Dr Anja Engel, was to understand the surface dynamics of organic carbon in coastal upwelling systems and the role of eddies in transporting it to the adjacent open ocean.
Becker, K.W., Devresse, Q., Prieto-Mollar, X., Hinrichs, K.U., & Engel, A. Mixed-layer lipidomes suggest offshore transport of energy-rich and essential lipids by cyclonic eddies. Commun Earth Environ 6, 179 (2025).
https://doi.org/10.1038/s43247-025-02152-0
http://www.geomar.de/n9800 Downloadable images
https://www.ebus-climate-change.de/de/reebus REEBUS project
https://www.geomar.de/forschen/aktuelle-projekte/detailansicht/prj/349891?cHash=... REEBUS project description
Merkmale dieser Pressemitteilung:
Journalisten
Biologie, Chemie, Meer / Klima, Tier / Land / Forst, Umwelt / Ökologie
überregional
Forschungsergebnisse
Englisch
Sie können Suchbegriffe mit und, oder und / oder nicht verknüpfen, z. B. Philo nicht logie.
Verknüpfungen können Sie mit Klammern voneinander trennen, z. B. (Philo nicht logie) oder (Psycho und logie).
Zusammenhängende Worte werden als Wortgruppe gesucht, wenn Sie sie in Anführungsstriche setzen, z. B. „Bundesrepublik Deutschland“.
Die Erweiterte Suche können Sie auch nutzen, ohne Suchbegriffe einzugeben. Sie orientiert sich dann an den Kriterien, die Sie ausgewählt haben (z. B. nach dem Land oder dem Sachgebiet).
Haben Sie in einer Kategorie kein Kriterium ausgewählt, wird die gesamte Kategorie durchsucht (z.B. alle Sachgebiete oder alle Länder).
