| Title: |
Iron dissolution from Patagonian dust in the Southern Ocean: under present and future conditions |
| Authors: |
Demasy, Clément; Boye, Marie; Lai, Barry; Burckel, Pierre; Feng, Yan; Losno, Rémi; Borensztajn, Stephan; Besson, Pascale |
| Contributors: |
Institut de Physique du Globe de Paris (IPG Paris); Institut de Physique du Globe de Paris (IPGP - UMR_7154); Institut national des sciences de l'Univers (INSU - CNRS)-Institut National de l'Information Géographique et Forestière IGN (IGN)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité); The author(s) declare financial support was received for theresearch, authorship, and/or publication of this article. This workwas conducted in the framework of the SAGAS project (Solubility ofPatagonian dust in the future Southern Ocean, PI MB) funded byIDEX-Université Paris Cité. CD benefited from an internationalmobility grant from the STEP’UP doctoral school of IPGP. ThePhD grant of CD was funded by the University Paris Cité. ICPQMSand SEM analyses were supported by IPGP analyticalplatform PARI (Plateforme d’analyse haute résolution). Thisresearch used resources of the Advanced Photon Source, a U.S.Department of Energy (DOE) Office of Science user facilityoperated for the DOE Office of Science by Argonne NationalLaboratory under Contract No. DE-AC02-06CH11357. |
| Source: |
ISSN: 2296-7745 ; Frontiers in Marine Science ; https://hal.science/hal-04574680 ; Frontiers in Marine Science, 2024, 11, ⟨10.3389/fmars.2024.1363088⟩. |
| Publisher Information: |
CCSD; Frontiers Media |
| Publication Year: |
2024 |
| Collection: |
Institut national des sciences de l'Univers: HAL-INSU |
| Subject Terms: |
[SDE]Environmental Sciences |
| Description: |
International audience ; Although the input of desert dust as a key source of trace metals in the Southern Ocean (SO) has been previously studied, the dissolution process of metals in surface waters, particularly iron (Fe), remain poorly understood. Given the crucial role of Fe in primary production and the biological carbon pump in the SO, we focused on experimental estimations of Fe dissolution from Patagonian dust, the primary natural dust source in the SO. Our study considered both current and projected future conditions, encompassing sea-surface warming, acidification, increased photosynthetically active radiation, and doubled dust inputs. Through controlled laboratory experiments using filtered SO seawater, conducted over 7 days, we assessed changes in particulate Fe (pFe) concentrations, Fe redox speciation (Fe(II)/Fe(III)), and in the mineralogy of Fe-bearing dust in abiotic condition. The predominant minerals in the dust included quartz and aluminosilicates, with silicon (Si), aluminum (Al), and Fe as the major elements. No significant alterations in the mineralogy and the elemental composition of the dust were recorded during the dissolution experiments, neither under present nor under projected future conditions. The particulate Fe(II)/Fe(III) ratio remained consistently at 0.25 during the experiments, unaffected by changed conditions. Consequently, changes in environmental conditions in the SO would therefore not significantly alter the mineralogy and redox speciation of pFe in the Patagonian dust. On the contrary, pFe exhibited a dissolution rate of 3.8% and 1.6% per day under present and future conditions, respectively. The environmental changes anticipated for 2100 in the SO will likely to result in a decrease in the dissolution rate of pFe. Thus, even though a doubling of dust input by 2100 is anticipated, it will unlikely provide significantly more dissolved Fe (dFe) in seawater in the SO. Consequently, the future intensification of Patagonian dust inputs may not alleviate the Fe limitation in ... |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.3389/fmars.2024.1363088 |
| Availability: |
https://hal.science/hal-04574680; https://hal.science/hal-04574680v1/document; https://hal.science/hal-04574680v1/file/fmars-11-1363088.pdf; https://doi.org/10.3389/fmars.2024.1363088 |
| Rights: |
http://creativecommons.org/licenses/by/ ; info:eu-repo/semantics/OpenAccess |
| Accession Number: |
edsbas.BF3BF8EC |
| Database: |
BASE |