Biogeochemical controls on ocean productivity

We are interested in the controls on phytoplankton physiology and community structure in the global ocean, with a particular focus on regulation by (micro)nutrients. We conduct a range of fieldwork (mostly open ocean research cruises), phytoplankton culturing experiments, numerical analysis and simple modelling to investigate this. In the European Research Council (ERC) funded project ‘Ocean Glow’ we are trying to develop a method to observe phytoplankton nutrient limitation at global, high frequency scales using satellite remote sensing of chlorophyll fluorescence - red light that is emitted from phytoplankton and radiates out into space.

Research Areas

Sources and cycling of ocean (micro)nutrients
Phytoplankton ecophysiology
Remote sensing of phytoplankton
Controls on ocean nitrogen fixation
Climate change

Project Overview

Ocean Glow
ERC Starting grant project to investigate the potential for observing phytoplankton nutrient limitation from space using sunlight-stimulated fluorescence signals
Funded by the European Research Council
ReSEAt
Project in the South Atlantic Ocean investigating filaments of cold, nutrient rich water that upwell in the Benguela and advect offshore into the nutrient-impoverished South Atlantic Gyre
Funded by the DFG
EMS-FORE/EMS-PS
Project investigating the ‘Eastern Mediterranean Sea as a model for Future Ocean Research’ (EMS-FORE) with the associated project ‘Eastern Mediterranean Sea - Process Study’, which was a cruise on the RV Meteor we led in early 2024 to investigate the biogeochemistry of the Eastern Mediterranean, with observations from aerosols, ocean to seafloor
Funded by the DFG (EMS-PS) and Helmholtz (EMS-FORE)
GEOTRACES GP11
Project investigating the biogeochemistry of the Equatorial Pacific, with a focus on the role of iron supply in regulating ocean productivity
Funded by the BMBF
EqPac co-limitation
Project in the Equatorial Pacific (on RV Sonne) investigating phytoplankton nutrient limitation at a range of scales, from nutrient deficiency (via (micro)nutrient concentrations), nutrient stress (via metaproteomics), and nutrient limitation (via bioassay experiments). We then linked phytoplankton nutrient limitation regimes to their fluorescence characteristics, which formed the basis for the ERC ‘Ocean Glow’ project
Funded by the BMBF
Highlight publications:
Browning, T.J., Saito, M.A., Garaba, S.P., Wang, X., Achterberg, E.P., Moore, C.M., Engel, A., Mcllvin, M.R., Moran, D., Voss, D. and Zielinski, O., 2023. Persistent equatorial Pacific iron limitation under ENSO forcing. Nature, 621(7978), pp.330-335.
Rainbow
Project in the subtropical North Atlantic investigating nitrogen-phosphorus co-limitation of phytoplankton productivity and phosphorus-iron limitation of nitrogen fixation
Funded by the DFG
Highlight publications:
Yuan, Z., Achterberg, E.P., Engel, A., Dai, M. and Browning, T.J., 2024. Switches between nitrogen limitation and nitrogen–phosphorus co‐limitation in the subtropical North Atlantic Ocean. Limnology and Oceanography, 69(4), pp.1005-1013.
Yuan, Z., Achterberg, E.P., Engel, A., Wen, Z., Zhou, L., Zhu, X., Dai, M. and Browning, T.J., 2023. Phytoplankton community response to episodic wet and dry aerosol deposition in the subtropical North Atlantic. Limnology and Oceanography, 68(9), pp.2126-2140.

Overview

Scientists on RV Meteor cruise M187

Zhongwei Yuan preparing a nutrient addition experiment on RV Sonne Cruise SO289

Angèle Nicolas in the trace metal sampling lab on RV Meteor cruise M187

Scientists on Meteor cruise M197

Explaining our research to fellow GEOMAR scientists

Team on RV Sonne Cruise SO289

Mapping upwelled filaments on RV Meteor cruise M187

Publications

The publications of this group can be found here.

RD2

Marine Biogeochemistry

Working Group

Head of Working Group
"Biogeochemical controls on ocean productivity"
Dr. Thomas Browning
GEOMAR Helmholtz Centre
for Ocean Research Kiel
Wischhofstraße 1-3
24148 Kiel
Building: 12, Room: 321
Tel.: +49 (0) 431 600-1289
E-Mail: tbrowning(at)geomar.de
Jenna Belaguer
Brandy Robinson
Zhongwei Yuan
Ze Chen
Angèle Nicolas
Martin Müller
Anjala Gammanpila
Zuozhu Wen
Haoran Liu
Xuechao Wang
Maxime Gautier
Juliane Tammen

On-going projects

Finished Projects