High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom
Little is known about the bioavailability of iron (Fe) in natural dusts and the impact of dust mineralogy on Fe utilization by photosynthetic organisms. Variation in the supply of bioavailable Fe to the ocean has the potential to influence the global carbon cycle by modulating primary production in...
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ftcolumbiauniv:oai:academiccommons.columbia.edu:10.7916/D83B78F6 2023-05-15T18:24:42+02:00 High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom Shoenfelt, Elizabeth M. Sun, Jing Winckler, Gisela Kaplan, Michael Borunda, Alejandra Farrell, Kayla R. Moreno, Patricio Gaiero, Diego M. Recasens, Cristina Sambrotto, Raymond N. Bostick, Benjamin C. 2017 https://doi.org/10.7916/D83B78F6 English eng https://doi.org/10.7916/D83B78F6 Iron Loess Mineralogy Diatoms Iron--Bioavailability Environmental sciences Articles 2017 ftcolumbiauniv https://doi.org/10.7916/D83B78F6 2019-04-04T08:16:42Z Little is known about the bioavailability of iron (Fe) in natural dusts and the impact of dust mineralogy on Fe utilization by photosynthetic organisms. Variation in the supply of bioavailable Fe to the ocean has the potential to influence the global carbon cycle by modulating primary production in the Southern Ocean. Much of the dust deposited across the Southern Ocean is sourced from South America, particularly Patagonia, where the waxing and waning of past and present glaciers generate fresh glaciogenic material that contrasts with aged and chemically weathered nonglaciogenic sediments. We show that these two potential sources of modern-day dust are mineralogically distinct, where glaciogenic dust sources contain mostly Fe(II)-rich primary silicate minerals, and nearby nonglaciogenic dust sources contain mostly Fe(III)-rich oxyhydroxide and Fe(III) silicate weathering products. In laboratory culture experiments, Phaeodactylum tricornutum, a well-studied coastal model diatom, grows more rapidly, and with higher photosynthetic efficiency, with input of glaciogenic particulates compared to that of nonglaciogenic particulates due to these differences in Fe mineralogy. Monod nutrient accessibility models fit to our data suggest that particulate Fe(II) content, rather than abiotic solubility, controls the Fe bioavailability in our Fe fertilization experiments. Thus, it is possible for this diatom to access particulate Fe in dusts by another mechanism besides uptake of unchelated Fe (Fe′) dissolved from particles into the bulk solution. If this capability is widespread in the Southern Ocean, then dusts deposited to the Southern Ocean in cold glacial periods are likely more bioavailable than those deposited in warm interglacial periods. Article in Journal/Newspaper Southern Ocean Columbia University: Academic Commons Patagonia Southern Ocean |
institution |
Open Polar |
collection |
Columbia University: Academic Commons |
op_collection_id |
ftcolumbiauniv |
language |
English |
topic |
Iron Loess Mineralogy Diatoms Iron--Bioavailability Environmental sciences |
spellingShingle |
Iron Loess Mineralogy Diatoms Iron--Bioavailability Environmental sciences Shoenfelt, Elizabeth M. Sun, Jing Winckler, Gisela Kaplan, Michael Borunda, Alejandra Farrell, Kayla R. Moreno, Patricio Gaiero, Diego M. Recasens, Cristina Sambrotto, Raymond N. Bostick, Benjamin C. High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom |
topic_facet |
Iron Loess Mineralogy Diatoms Iron--Bioavailability Environmental sciences |
description |
Little is known about the bioavailability of iron (Fe) in natural dusts and the impact of dust mineralogy on Fe utilization by photosynthetic organisms. Variation in the supply of bioavailable Fe to the ocean has the potential to influence the global carbon cycle by modulating primary production in the Southern Ocean. Much of the dust deposited across the Southern Ocean is sourced from South America, particularly Patagonia, where the waxing and waning of past and present glaciers generate fresh glaciogenic material that contrasts with aged and chemically weathered nonglaciogenic sediments. We show that these two potential sources of modern-day dust are mineralogically distinct, where glaciogenic dust sources contain mostly Fe(II)-rich primary silicate minerals, and nearby nonglaciogenic dust sources contain mostly Fe(III)-rich oxyhydroxide and Fe(III) silicate weathering products. In laboratory culture experiments, Phaeodactylum tricornutum, a well-studied coastal model diatom, grows more rapidly, and with higher photosynthetic efficiency, with input of glaciogenic particulates compared to that of nonglaciogenic particulates due to these differences in Fe mineralogy. Monod nutrient accessibility models fit to our data suggest that particulate Fe(II) content, rather than abiotic solubility, controls the Fe bioavailability in our Fe fertilization experiments. Thus, it is possible for this diatom to access particulate Fe in dusts by another mechanism besides uptake of unchelated Fe (Fe′) dissolved from particles into the bulk solution. If this capability is widespread in the Southern Ocean, then dusts deposited to the Southern Ocean in cold glacial periods are likely more bioavailable than those deposited in warm interglacial periods. |
format |
Article in Journal/Newspaper |
author |
Shoenfelt, Elizabeth M. Sun, Jing Winckler, Gisela Kaplan, Michael Borunda, Alejandra Farrell, Kayla R. Moreno, Patricio Gaiero, Diego M. Recasens, Cristina Sambrotto, Raymond N. Bostick, Benjamin C. |
author_facet |
Shoenfelt, Elizabeth M. Sun, Jing Winckler, Gisela Kaplan, Michael Borunda, Alejandra Farrell, Kayla R. Moreno, Patricio Gaiero, Diego M. Recasens, Cristina Sambrotto, Raymond N. Bostick, Benjamin C. |
author_sort |
Shoenfelt, Elizabeth M. |
title |
High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom |
title_short |
High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom |
title_full |
High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom |
title_fullStr |
High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom |
title_full_unstemmed |
High particulate iron(II) content in glacially sourced dusts enhances productivity of a model diatom |
title_sort |
high particulate iron(ii) content in glacially sourced dusts enhances productivity of a model diatom |
publishDate |
2017 |
url |
https://doi.org/10.7916/D83B78F6 |
geographic |
Patagonia Southern Ocean |
geographic_facet |
Patagonia Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_relation |
https://doi.org/10.7916/D83B78F6 |
op_doi |
https://doi.org/10.7916/D83B78F6 |
_version_ |
1766205521910562816 |