Seasonal resource conditions favor a summertime increase in North Pacific diatom–diazotroph associations
In the North Pacific Subtropical Gyre (NPSG), an annual pulse of sinking organic carbon is observed at 4000 m between July and August, driven by large diatoms found in association with nitrogen fixing, heterocystous, cyanobacteria: Diatom-Diazotroph Associations (DDAs). Here we ask what drives the b...
| Main Authors: | , , , , |
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| Format: | Article |
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Nature Publishing Group
2018
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| Online Access: | http://hdl.handle.net/1721.1/118343 https://orcid.org/0000-0002-7164-1660 https://orcid.org/0000-0002-1627-2014 https://orcid.org/0000-0002-3102-0341 |
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| author | Karl, David M. Follett, Christopher L Dutkiewicz, Stephanie Inomura, Keisuke Follows, Michael J |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Karl, David M. Follett, Christopher L Dutkiewicz, Stephanie Inomura, Keisuke Follows, Michael J |
| author_sort | Karl, David M. |
| collection | MIT |
| description | In the North Pacific Subtropical Gyre (NPSG), an annual pulse of sinking organic carbon is observed at 4000 m between July and August, driven by large diatoms found in association with nitrogen fixing, heterocystous, cyanobacteria: Diatom-Diazotroph Associations (DDAs). Here we ask what drives the bloom of DDAs and present a simplified trait-based model of subtropical phototroph populations driven by observed, monthly averaged, environmental characteristics. The ratio of resource supply rates favors nitrogen fixation year round. The relative fitness of DDA traits is most competitive in early summer when the mixed layer is shallow, solar irradiance is high, and phosphorus and iron are relatively abundant. Later in the season, as light intensity drops and phosphorus is depleted, the traits of small unicellular diazotrophs become more competitive. The competitive transition happens in August, at the time when the DDA export event occurs. This seasonal dynamic is maintained when embedded in a more complex, global-scale, ecological model, and provides predictions for the extent of the North Pacific DDA bloom. The model provides a parsimonious and testable hypothesis for the stimulation of DDA blooms. |
| first_indexed | 2024-09-23T08:19:57Z |
| format | Article |
| id | mit-1721.1/118343 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T08:19:57Z |
| publishDate | 2018 |
| publisher | Nature Publishing Group |
| record_format | dspace |
| spelling | mit-1721.1/1183432022-09-23T12:22:56Z Seasonal resource conditions favor a summertime increase in North Pacific diatom–diazotroph associations Karl, David M. Follett, Christopher L Dutkiewicz, Stephanie Inomura, Keisuke Follows, Michael J Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Follett, Christopher L Dutkiewicz, Stephanie Inomura, Keisuke Follows, Michael J In the North Pacific Subtropical Gyre (NPSG), an annual pulse of sinking organic carbon is observed at 4000 m between July and August, driven by large diatoms found in association with nitrogen fixing, heterocystous, cyanobacteria: Diatom-Diazotroph Associations (DDAs). Here we ask what drives the bloom of DDAs and present a simplified trait-based model of subtropical phototroph populations driven by observed, monthly averaged, environmental characteristics. The ratio of resource supply rates favors nitrogen fixation year round. The relative fitness of DDA traits is most competitive in early summer when the mixed layer is shallow, solar irradiance is high, and phosphorus and iron are relatively abundant. Later in the season, as light intensity drops and phosphorus is depleted, the traits of small unicellular diazotrophs become more competitive. The competitive transition happens in August, at the time when the DDA export event occurs. This seasonal dynamic is maintained when embedded in a more complex, global-scale, ecological model, and provides predictions for the extent of the North Pacific DDA bloom. The model provides a parsimonious and testable hypothesis for the stimulation of DDA blooms. Simons Foundation (Award 329108) National Science Foundation (U.S.) (Grant OCE-1434007) Gordon and Betty Moore Foundation (Grant GBMF3778) Gordon and Betty Moore Foundation (Grant GBMF3794) 2018-10-03T17:47:56Z 2018-10-03T17:47:56Z 2018-02 2017-10 2018-09-24T16:56:27Z Article http://purl.org/eprint/type/JournalArticle 1751-7362 1751-7370 http://hdl.handle.net/1721.1/118343 Follett, Christopher L., Stephanie Dutkiewicz, David M. Karl, Keisuke Inomura, and Michael J. Follows. “Seasonal Resource Conditions Favor a Summertime Increase in North Pacific Diatom–diazotroph Associations.” The ISME Journal 12, 6 (February 2018): 1543–1557 © 2018 The Author(s) https://orcid.org/0000-0002-7164-1660 https://orcid.org/0000-0002-1627-2014 https://orcid.org/0000-0002-3102-0341 http://dx.doi.org/10.1038/S41396-017-0012-X ISME Journal Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Nature Publishing Group Nature |
| spellingShingle | Karl, David M. Follett, Christopher L Dutkiewicz, Stephanie Inomura, Keisuke Follows, Michael J Seasonal resource conditions favor a summertime increase in North Pacific diatom–diazotroph associations |
| title | Seasonal resource conditions favor a summertime increase in North Pacific diatom–diazotroph associations |
| title_full | Seasonal resource conditions favor a summertime increase in North Pacific diatom–diazotroph associations |
| title_fullStr | Seasonal resource conditions favor a summertime increase in North Pacific diatom–diazotroph associations |
| title_full_unstemmed | Seasonal resource conditions favor a summertime increase in North Pacific diatom–diazotroph associations |
| title_short | Seasonal resource conditions favor a summertime increase in North Pacific diatom–diazotroph associations |
| title_sort | seasonal resource conditions favor a summertime increase in north pacific diatom diazotroph associations |
| url | http://hdl.handle.net/1721.1/118343 https://orcid.org/0000-0002-7164-1660 https://orcid.org/0000-0002-1627-2014 https://orcid.org/0000-0002-3102-0341 |
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