The University of Southampton
University of Southampton Institutional Repository

Modeling the speciation and biogeochemistry of iron at the Bermuda Atlantic Time-series Study site

Modeling the speciation and biogeochemistry of iron at the Bermuda Atlantic Time-series Study site
Modeling the speciation and biogeochemistry of iron at the Bermuda Atlantic Time-series Study site
By means of numerical modeling, we analyze the cycling of iron between its various physical (dissolved, colloidal, particulate) and chemical (redox state and organic complexation) forms in the upper mixed layer. With our proposed model it is possible to obtain a first quantitative assessment of how this cycling influences iron uptake by phytoplankton and its loss via particle export. The model is forced with observed dust deposition rates, mixed layer depths, and solar radiation at the site of the Bermuda Atlantic Time-series Study (BATS). It contains an objectively optimized ecosystem model which yields results close to the observational data from BATS that has been used for the data-assimilation procedure. It is shown that the mixed layer cycle strongly influences the cycling of iron between its various forms. This is mainly due to the light dependency of photoreductive processes, and to the seasonality of primary production. The daily photochemical cycle is driven mainly by the production of superoxide, and its amplitude depends on the concentration and speciation of dissolved copper. Model results are almost insensitive to the dominant form of dissolved iron within dust deposition, and also to the form of iron that is taken up directly during algal growth. In our model solutions, the role of the colloidal pumping mechanism depends strongly on assumptions on the colloid aggregation and photoreduction rate.
biogeochemical cycles, ecosystem modeling, iron
0886-6236
GB1019
Weber, L.
d7348d6d-978f-4eca-af3c-0fdfe2567426
Völker, C.
e7a71491-b51a-4c9b-84ae-d62a7d2b7a2e
Schartau, M.
d43a9d16-4202-42fa-83a3-2147a14df490
Wolf-Gladrow, D.A.
6851bee4-9dda-4ad8-8999-80cc6d0fe422
Weber, L.
d7348d6d-978f-4eca-af3c-0fdfe2567426
Völker, C.
e7a71491-b51a-4c9b-84ae-d62a7d2b7a2e
Schartau, M.
d43a9d16-4202-42fa-83a3-2147a14df490
Wolf-Gladrow, D.A.
6851bee4-9dda-4ad8-8999-80cc6d0fe422

Weber, L., Völker, C., Schartau, M. and Wolf-Gladrow, D.A. (2005) Modeling the speciation and biogeochemistry of iron at the Bermuda Atlantic Time-series Study site. Global Biogeochemical Cycles, 19, GB1019. (doi:10.1029/2004GB002340).

Record type: Article

Abstract

By means of numerical modeling, we analyze the cycling of iron between its various physical (dissolved, colloidal, particulate) and chemical (redox state and organic complexation) forms in the upper mixed layer. With our proposed model it is possible to obtain a first quantitative assessment of how this cycling influences iron uptake by phytoplankton and its loss via particle export. The model is forced with observed dust deposition rates, mixed layer depths, and solar radiation at the site of the Bermuda Atlantic Time-series Study (BATS). It contains an objectively optimized ecosystem model which yields results close to the observational data from BATS that has been used for the data-assimilation procedure. It is shown that the mixed layer cycle strongly influences the cycling of iron between its various forms. This is mainly due to the light dependency of photoreductive processes, and to the seasonality of primary production. The daily photochemical cycle is driven mainly by the production of superoxide, and its amplitude depends on the concentration and speciation of dissolved copper. Model results are almost insensitive to the dominant form of dissolved iron within dust deposition, and also to the form of iron that is taken up directly during algal growth. In our model solutions, the role of the colloidal pumping mechanism depends strongly on assumptions on the colloid aggregation and photoreduction rate.

This record has no associated files available for download.

More information

Published date: 2005
Keywords: biogeochemical cycles, ecosystem modeling, iron

Identifiers

Local EPrints ID: 42034
URI: http://eprints.soton.ac.uk/id/eprint/42034
ISSN: 0886-6236
PURE UUID: 7c2cfaec-3683-4823-9642-12181dd4353b

Catalogue record

Date deposited: 09 Feb 2007
Last modified: 15 Mar 2024 08:42

Export record

Altmetrics

Contributors

Author: L. Weber
Author: C. Völker
Author: M. Schartau
Author: D.A. Wolf-Gladrow

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.

×