Articles | Volume 22, issue 3
https://doi.org/10.5194/bg-22-625-2025
© 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-22-625-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Feb 2025
Research article |
| 04 Feb 2025
| 04 Feb 2025
Grazing mortality as a controlling factor in the uncultured non-cyanobacterial diazotroph (Gamma A) around the Kuroshio region
Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657, Japan
present address: Institute for Chemical Research, Kyoto University, Kyoto, 611-0011, Japan
Tamaha Yamaguchi
Fisheries Resources Institute, Japan Fisheries Research and Education Agency, Kanagawa, 236-8648, Japan
Kiyotaka Hidaka
Fisheries Resources Institute, Japan Fisheries Research and Education Agency, Kanagawa, 236-8648, Japan
Sayaka Sogawa
Fisheries Resources Institute, Japan Fisheries Research and Education Agency, Kanagawa, 236-8648, Japan
Takashi Setou
Fisheries Resources Institute, Japan Fisheries Research and Education Agency, Kanagawa, 236-8648, Japan
Taketoshi Kodama
Fisheries Resources Institute, Japan Fisheries Research and Education Agency, Kanagawa, 236-8648, Japan
present address: Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657, Japan
Takuhei Shiozaki
Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba, 277-8564, Japan
Kazutaka Takahashi
Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657, Japan
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Short summary
Gamma A is a widespread non-cyanobacterial diazotroph that plays a crucial role in marine ecosystems, but its controlling factors are still largely unknown. This study, for the first time, quantified microzooplankton grazing on Gamma A and revealed the significance of grazing pressure on Gamma A distribution around the Kuroshio region. It highlights the importance of top-down controls on Gamma A abundance and the associated nitrogen cycle.
Gamma A is a widespread non-cyanobacterial diazotroph that plays a crucial role in marine...
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