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Barraqueta, Jan-lukas Menzel; Schlosser, Christian; Planquette, Helene; Gourain, Arthur; Cheize, Marie; Boutorh, Julia; Shelley, Rachel; Pereira, Leonardo Contreira; Gledhill, Martha; Hopwood, Mark J.; Lacan, Francois; Lherminier, Pascale; Sarthou, Geraldine; Achterberg, Eric P.. |
The distribution of dissolved aluminium (dAl) in the water column of the North Atlantic and Labrador Sea was studied along GEOTRACES section GA01 to unravel the sources and sinks of this element. Surface water dAl concentrations were low (median of 2.5 nM) due to low aerosol deposition and removal by phytoplankton. However, surface water dAl concentrations were enhanced on the Iberian and Greenland shelves (up to 30.9 nM) due to continental inputs (rivers, glacial flour and ice melt). A negative correlation was observed between dAl in surface waters and primary production, phytoplankton community structure and biogenic opal production. The abundance of diatoms exerted a significant (p < 0.01) control on the surface particulate Al (pAl) to dAl ratios by... |
Tipo: Text |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00422/53359/54197.pdf |
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Menzel Barraqueta, Jan-lukas; Klar, Jessica K.; Gledhill, Martha; Schlosser, Christian; Shelley, Rachel; Planquette, Helene; Wenzel, Bernhard; Sarthou, Geraldine; Achterberg, Eric P.. |
Atmospheric deposition is an important source of micronutrients to the ocean, but atmospheric deposition fluxes remain poorly constrained in most ocean regions due to the limited number of field observations of wet and dry atmospheric inputs. Here we present the distribution of dissolved aluminium (dAl), as a tracer of atmospheric inputs, in surface waters of the Atlantic Ocean along GEOTRACES sections GA01, GA06, GA08, and GA10. We used the surface mixed layer concentrations of dAl to calculate atmospheric deposition fluxes using a simple steady state model. We have optimized the aerosol Al fractional solubility, dAl residence time within the surface mixed layer and depth of the surface mixed layer for each separate cruise to calculate the atmospheric... |
Tipo: Text |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00485/59675/62745.pdf |
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Menzel Barraqueta, Jan-lukas; Klar, Jessica K.; Gledhill, Martha; Schlosser, Christian; Shelley, Rachel; Planquette, Helene; Wenzel, Bernhard; Sarthou, Geraldine; Achterberg, Eric P.. |
Atmospheric deposition is an important source of micronutrients to the ocean, but atmospheric deposition fluxes remain poorly constrained in most ocean regions due to the limited number of field observations of wet and dry atmospheric inputs. Here we present the distribution of dissolved aluminium (dAl), as a tracer of atmospheric inputs, in surface waters of the Atlantic Ocean along GEOTRACES sections GA01, GA06, GA08, and GA10. We used the surface mixed-layer concentrations of dAl to calculate atmospheric deposition fluxes using a simple steady state model. We have optimized the Al fractional aerosol solubility, the dAl residence time within the surface mixed layer and the depth of the surface mixed layer for each separate cruise to calculate the... |
Tipo: Text |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00491/60227/63598.pdf |
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Louropoulou, Evangelia; Gledhill, Martha; Browningi, Thomas J.; Desai, Dhwani K.; Barraqueta, Jan-lukas Menzel; Tonnard, Manon; Sarthou, Geraldine; Planquette, Helene; Bowie, Andrew R.; Schmitz, Ruth A.; Laroche, Julie; Achterberg, Eric P.. |
Heme b is an iron-containing co-factor in hemoproteins. Heme b concentrations are low (< 1 pmol L-1) in iron limited phytoplankton in cultures and in the field. Here, we determined heme b in marine particulate material (> 0.7 mu m) from the North Atlantic Ocean (GEOVIDE cruise - GEOTRACES section GA01), which spanned several biogeochemical regimes. We examined the relationship between heme b abundance and the microbial community composition, and its utility for mapping iron limited phytoplankton. Heme b concentrations ranged from 0.16 to 5.1 pmol L-1 (median = 2.0 pmol L-1, n = 62) in the surface mixed layer (SML) along the cruise track, driven mainly by variability in biomass. However, in the Irminger Basin, the lowest heme b levels (SML: median =... |
Tipo: Text |
Palavras-chave: Heme b; North Atlantic; Phytoplankton; Diatoms; Iron; Limitation; GEOTRACES; GEOVIDE. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00508/61940/66029.pdf |
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