0000-0001-5212-6228 (Chappell)

Document Type


Publication Date




Publication Title

Limnology and Oceanography Letters








Phytoplankton iron contents (i.e., quotas) directly link biogeochemical cycles of iron and carbon and drive patterns of nutrient limitation, recycling, and export. Ocean biogeochemical models typically assume that iron quotas are either static or controlled by dissolved iron availability. We measured iron quotas in phytoplankton communities across nutrient gradients in the Pacific Ocean and found that quotas diverged significantly in taxon‐specific ways from laboratory‐derived predictions. Iron quotas varied 40‐fold across nutrient gradients, and nitrogen‐limitation allowed diatoms to accumulate fivefold more iron than co‐occurring flagellates even under low iron availability. Modeling indicates such “luxury” uptake is common in large regions of the low‐iron Pacific Ocean. Among diatoms, both pennate and centric genera accumulated luxury iron, but the cosmopolitan pennate genus Pseudo‐nitzschia maintained iron quotas 10‐fold higher than co‐occurring centric diatoms, likely due to enhanced iron storage. Biogeochemical models should account for taxonomic and macronutrient controls on phytoplankton iron quotas.


© 2020 The Authors.

This is an open access article under the terms of the Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Data Availability

Article states: "Data and metadata are available at the U.S. Biological and Chemical Oceanography Data Management Office (BCO-DMO): EPZT cruise—https://www.bco-dmo.org/dataset/639847, https://www.bco-dmo.org/dataset/643270; GeoMICS cruise—https://www.bco-dmo.org/project/517510, https://www.bco-dmo.org/dataset/664975; IRNBRU cruise—https://www.bco-dmo.org/project/527114, https://www.bco-dmo.org/dataset/663183. Nutrient, dFe, pigment, particulate Fe, and SXRF data for EPZT cruise are also available from the GEOTRACES International Data Assembly Centre (https://www.bodc.ac.uk/geotraces/data/idp2017/)."

Original Publication Citation

Twining, B. S., Antipova, O., Chappell, P. D., Cohen, N. R., Jacquot, J. E., Mann, E. L., Marchetti, A., Ohnemus, D. C., Rauschenberg, S., & Tagliabue, A. (2021). Taxonomic and nutrient controls on phytoplankton iron quotas in the ocean. Limnology and Oceanography Letters, 6(2), 96-106. https://doi.org/10.1002/lol2.10179


Article Location