The University of Southampton
University of Southampton Institutional Repository

Quantifying export production in the Southern Ocean: Implications for the Baxsproxy

Quantifying export production in the Southern Ocean: Implications for the Baxsproxy
Quantifying export production in the Southern Ocean: Implications for the Baxsproxy
The water column and sedimentary Baxs distribution around the Crozet Plateau is used to decipher the controls and timing of barite formation and to evaluate how export production signals are recorded in sediments underlying a region of natural Fe fertilization within the Fe limited Southern Ocean. Export production estimated from preserved, vertical sedimentary Baxs accumulation rates are compared with published export fluxes assessed from an integrated study of the biological carbon pump to determine the validity of Baxs as a quantitative proxy under different Fe supply conditions typical of the Southern Ocean. Detailed assessment of the geochemical partitioning of Ba in sediments and the lithogenic end-member allows appropriate correction of the bulk Ba content and determination of the Baxs content of sediments and suspended particles. The upper water column distribution of Baxs is extremely heterogeneous spatially and temporally. Organic carbon/Baxs ratios in deep traps from the Fe fertilized region are similar to other oceanic settings allowing quantification of the inferred carbon export based on established algorithms. There appears to be some decoupling of POC and Ba export in the Fe limited region south of the Plateau. The export production across the Crozet Plateau inferred from the Baxs sedimentary proxy indicates that the Fe fertilized area to the north of the Plateau experiences enhanced export relative to equivalent Southern Ocean settings throughout the Holocene and that this influence may also have impacted the site to the south for significant periods. This interpretation is corroborated by alternative productivity proxies (opal accumulation, 231Paxs/230Thxs). Baxs can be used to quantify export production in complex settings such as naturally Fe-fertilized (volcanoclastic) areas, providing appropriate lithogenic correction is undertaken, and sediment focusing is corrected for along with evaluation of barite preservation.
0883-8305
PA4222
Hernandez-Sanchez, Maria T.
aab022ef-6dd6-4e6d-8e8e-679231857261
Mills, Rachel A.
a664f299-1a34-4b63-9988-1e599b756706
Planquette, Hélène
99d8fde6-e561-47f0-9854-a35d42edfd26
Pancost, Richard D.
5914e19e-7777-4304-9fd8-86e2e9cfe8a1
Hepburn, Laura
be64e60e-317b-4eeb-afa2-57154ee8741a
Salter, Ian
b38c8ced-835b-4732-ac38-df1c93a0c1ba
FitzGeorge-Balfour, Tania
46b896f4-8b96-4d64-a046-309141f474d0
Hernandez-Sanchez, Maria T.
aab022ef-6dd6-4e6d-8e8e-679231857261
Mills, Rachel A.
a664f299-1a34-4b63-9988-1e599b756706
Planquette, Hélène
99d8fde6-e561-47f0-9854-a35d42edfd26
Pancost, Richard D.
5914e19e-7777-4304-9fd8-86e2e9cfe8a1
Hepburn, Laura
be64e60e-317b-4eeb-afa2-57154ee8741a
Salter, Ian
b38c8ced-835b-4732-ac38-df1c93a0c1ba
FitzGeorge-Balfour, Tania
46b896f4-8b96-4d64-a046-309141f474d0

Hernandez-Sanchez, Maria T., Mills, Rachel A., Planquette, Hélène, Pancost, Richard D., Hepburn, Laura, Salter, Ian and FitzGeorge-Balfour, Tania (2011) Quantifying export production in the Southern Ocean: Implications for the Baxsproxy. Paleoceanography, 26 (4), PA4222. (doi:10.1029/2010PA002111).

Record type: Article

Abstract

The water column and sedimentary Baxs distribution around the Crozet Plateau is used to decipher the controls and timing of barite formation and to evaluate how export production signals are recorded in sediments underlying a region of natural Fe fertilization within the Fe limited Southern Ocean. Export production estimated from preserved, vertical sedimentary Baxs accumulation rates are compared with published export fluxes assessed from an integrated study of the biological carbon pump to determine the validity of Baxs as a quantitative proxy under different Fe supply conditions typical of the Southern Ocean. Detailed assessment of the geochemical partitioning of Ba in sediments and the lithogenic end-member allows appropriate correction of the bulk Ba content and determination of the Baxs content of sediments and suspended particles. The upper water column distribution of Baxs is extremely heterogeneous spatially and temporally. Organic carbon/Baxs ratios in deep traps from the Fe fertilized region are similar to other oceanic settings allowing quantification of the inferred carbon export based on established algorithms. There appears to be some decoupling of POC and Ba export in the Fe limited region south of the Plateau. The export production across the Crozet Plateau inferred from the Baxs sedimentary proxy indicates that the Fe fertilized area to the north of the Plateau experiences enhanced export relative to equivalent Southern Ocean settings throughout the Holocene and that this influence may also have impacted the site to the south for significant periods. This interpretation is corroborated by alternative productivity proxies (opal accumulation, 231Paxs/230Thxs). Baxs can be used to quantify export production in complex settings such as naturally Fe-fertilized (volcanoclastic) areas, providing appropriate lithogenic correction is undertaken, and sediment focusing is corrected for along with evaluation of barite preservation.

This record has no associated files available for download.

More information

Published date: 2011
Organisations: Geochemistry, Marine Biogeochemistry, Marine Geoscience

Identifiers

Local EPrints ID: 208511
URI: http://eprints.soton.ac.uk/id/eprint/208511
ISSN: 0883-8305
PURE UUID: a548ecd3-972c-4707-a38b-fed4b81cd5c3
ORCID for Rachel A. Mills: ORCID iD orcid.org/0000-0002-9811-246X

Catalogue record

Date deposited: 19 Jan 2012 14:37
Last modified: 15 Mar 2024 02:46

Export record

Altmetrics

Contributors

Author: Maria T. Hernandez-Sanchez
Author: Rachel A. Mills ORCID iD
Author: Hélène Planquette
Author: Richard D. Pancost
Author: Laura Hepburn
Author: Ian Salter
Author: Tania FitzGeorge-Balfour

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×