Articles | Volume 20, issue 14
https://doi.org/10.5194/bg-20-3073-2023
© Author(s) 2023. 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-20-3073-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
31 Jul 2023
Research article |
| 31 Jul 2023
| 31 Jul 2023
Absence of photophysiological response to iron addition in autumn phytoplankton in the Antarctic sea-ice zone
Asmita Singh
Department of Earth Sciences, University of Stellenbosch,
Stellenbosch, South Africa
Southern Ocean Carbon–Climate Observatory, CSIR, Cape Town, South
Africa
Susanne Fietz
Department of Earth Sciences, University of Stellenbosch,
Stellenbosch, South Africa
Sandy J. Thomalla
Southern Ocean Carbon–Climate Observatory, CSIR, Cape Town, South
Africa
Marine and Antarctic Research for Innovation and Sustainability, University of Cape Town, Cape Town, South Africa
Nicolas Sanchez
Department of Chemistry, Norwegian University of Science and
Technology (NTNU), Trondheim, Norway
Murat V. Ardelan
Department of Chemistry, Norwegian University of Science and
Technology (NTNU), Trondheim, Norway
Sébastien Moreau
Norwegian Polar Institute (NPI), Tromsø, Norway
Centre for Ice, Cryosphere, Carbon and Climate, Department of
Geosciences, UiT, The Arctic University of Norway, Tromsø, Norway
Hanna M. Kauko
Norwegian Polar Institute (NPI), Tromsø, Norway
Agneta Fransson
Norwegian Polar Institute (NPI), Tromsø, Norway
Melissa Chierici
Institute of Marine Research, Fram Centre, Tromsø, Norway
Saumik Samanta
Department of Earth Sciences, University of Stellenbosch,
Stellenbosch, South Africa
Thato N. Mtshali
Oceans and Coasts, Department of Forestry, Fisheries, and the Environment,
Cape Town, South Africa
Alakendra N. Roychoudhury
Department of Earth Sciences, University of Stellenbosch,
Stellenbosch, South Africa
Thomas J. Ryan-Keogh
CORRESPONDING AUTHOR
Southern Ocean Carbon–Climate Observatory, CSIR, Cape Town, South
Africa
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Short summary
Despite the scarcity of iron in the Southern Ocean, seasonal blooms occur due to changes in nutrient and light availability. Surprisingly, during an autumn bloom in the Antarctic sea-ice zone, the results from incubation experiments showed no significant photophysiological response of phytoplankton to iron addition. This suggests that ambient iron concentrations were sufficient, challenging the notion of iron deficiency in the Southern Ocean through extended iron-replete post-bloom conditions.
Despite the scarcity of iron in the Southern Ocean, seasonal blooms occur due to changes in...
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