Data/hora: 02/06/2024 00:57:22

Provedor de dados: 	Institutional Archive of Ifreme (ArchiMer)	
País: 	France	
Título: 	Inputs and processes affecting the distribution of particulate iron in the North Atlantic along the GEOVIDE (GEOTRACES GA01) section	
Autores: 	Gourain, Arthur; Planquette, Helene; Cheize, Marie; Lemaitre, Nolwenn; Menzel Barraqueta, Jan-lukas; Shelley, Rachel; Lherminier, Pascale; Sarthou, Geraldine.	
Data: 	2019-04	
Ano: 	2019	
Resumo: 	The GEOVIDE cruise (May–June 2014, R/V Pourquoi Pas?) aimed to provide a better understanding on trace metal biogeochemical cycles in the North Atlantic. As particles play a key role in the global biogeochemical cycle of trace elements in the ocean, we discuss the distribution of particulate iron (PFe), in light of particulate aluminium (PAl), manganese (PMn) and phosphorus (PP) distributions. Overall, 32 full vertical profiles were collected for trace metal analyses, representing more than 500 samples. This resolution provides a solid basis for assessing concentration distributions, elemental ratios, size-fractionation, or adsorptive scavenging processes in key areas of the thermohaline circulation. Total particulate iron (PFe) concentrations ranged from as low as 9 pmol L−1 in surface Labrador Sea waters to 304 nmol L−1 near the Iberian margin, while median PFe concentrations of 1.15 nmol L−1 were measured over the sub-euphotic ocean interior. At most stations over the Western, the relative concentrations of total PFe and aluminium (PAl) showed the near-ubiquitous influence of crustal particles in the water column. Overall, the lithogenic component explained more than 87 % of PFe variance along the section. Within the Irminger and Labrador basins, the formation of biogenic particles led to an increase of the PFe / PAl ratio (up to 0.7 mol mol−1) compared to the continental crust ratio (0.21 mol mol−1), Margins provide important quantities of particulate trace elements (up to 10 nmol L−1 of PFe) to the open ocean, and in the case of the Iberian margin, advection of PFe was visible more than 250 km away from the margin. Additionally, several benthic nepheloid layers spreading over 200m above the seafloor were encountered along the transect, especially in the Icelandic, Irminger and Labrador basins, delivering particles with high PFe content, up to 89 nmol L−1 of PFe. Finally, remineralisation processes are also discussed, and showed different patterns among basins and elements.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	https://archimer.ifremer.fr/doc/00485/59676/62747.pdf

https://archimer.ifremer.fr/doc/00485/59676/62748.pdf

https://archimer.ifremer.fr/doc/00485/59676/63594.pdf

https://archimer.ifremer.fr/doc/00485/59676/63595.pdf

DOI:10.5194/bg-2018-234

https://archimer.ifremer.fr/doc/00485/59676/	
Editor: 	Copernicus GmbH	
Formato: 	application/pdf	
Fonte: 	Biogeosciences (1726-4170) (Copernicus GmbH), 2019-04 , Vol. 16 , N. 7 , P. 1563-1582	
Fonte: 	info:eu-repo/semantics/openAccess

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