Particulate Trace Element Export in the North Atlantic (GEOTRACES GA01 Transect, GEOVIDE Cruise)

Type Article
Date 2020-11
Language English
Author(s) Lemaitre Nolwenn1, 2, 3, Planquette Helene2, Dehairs Frank3, Planchon Frederic2, Sarthou Geraldine2, Gallinari Morgane2, Roig Stéphane2, Jeandel Catherine4, Castrillejo Maxi5
Affiliation(s) 1 : Institute of Geochemistry and Petrology, ETH-Zurich, Clausiusstrasse 25, 8092 Zurich, Switzerland
2 : CNRS, Université de Brest, IRD, Ifremer, LEMAR, Technopôle Brest-Iroise, 29280 Plouzané, France
3 : Analytical, Environmental, and Geo-Chemistry, Vrije Universiteit Brussel, Pleinlaan, 1050 Brussels, Belgium
4 : LEGOS, Université de Toulouse (CNRS/CNES/IRD/UPS), Observatoire Midi Pyrénées, 31400 Toulouse, France
5 : Laboratory of Ion Beam Physics, ETH-Zurich, Otto Stern Weg 5, 8093 Zurich, Switzerland
Source Acs Earth And Space Chemistry (2472-3452) (American Chemical Society (ACS)), 2020-11 , Vol. 4 , N. 11 , P. 2185-2204
DOI 10.1021/acsearthspacechem.0c00045
Keyword(s) particulate trace elements, export fluxes, multiple carrier phases, residence times, GEOTRACES
Abstract

Vertical export of particulate trace elements (pTEs) is a critically underconstrained aspect of their biogeochemistry. Here, we combine elemental analyses on large (>53 μm) particles and 234Th measurements to determine downward export fluxes from the upper layers (40–110 m) of pTEs (Al, Cd, Co, Cu, Fe, Mn, Ni, P, Ti, V, Zn) and mineral phases (lithogenic, Fe- and Mn-oxides, calcium carbonate, and opal) in the North Atlantic along the GEOVIDE transect (Portugal–Greenland–Canada; GEOTRACES GA01 cruise). The role of lithogenic particles in controlling TE fluxes is obvious at proximity of the Iberian margin where the highest pTE export fluxes were estimated (up to 3912 μg/m2/d for pFe). However, high lithogenic and pTE fluxes are also observed up to 1700 km off this margin in the west European and Icelandic basins (up to 931 μg/m2/d for pFe). The lowest pTE export fluxes are determined in the Labrador Sea (as low as 501 μg/m2/d for pFe). High Mn- and Fe-oxide fluxes are estimated at the open ocean stations, suggesting that authigenic particles are an important vector of pTEs. All along the transect, biogenic particles also drive the pTE export fluxes, as shown by the similar pTE/POC ratios between exports and phytoplankton quotas. The shortest residence times (dissolved + particulate) are generally observed where lithogenic particles control the pTE fluxes (as low as 2 days for Fe) whereas pTEs seem to be longer retained when the contribution of biogenic particles become greater (residence times up to 147 days for Fe).

Full Text
File Pages Size Access
20 4 MB Access on demand
13 2 MB Access on demand
Author's final draft 53 2 MB Open access
Top of the page

How to cite 

Lemaitre Nolwenn, Planquette Helene, Dehairs Frank, Planchon Frederic, Sarthou Geraldine, Gallinari Morgane, Roig Stéphane, Jeandel Catherine, Castrillejo Maxi (2020). Particulate Trace Element Export in the North Atlantic (GEOTRACES GA01 Transect, GEOVIDE Cruise). Acs Earth And Space Chemistry, 4(11), 2185-2204. Publisher's official version : https://doi.org/10.1021/acsearthspacechem.0c00045 , Open Access version : https://archimer.ifremer.fr/doc/00656/76810/