Iron biogeochemistry in Antarctic pack ice during SIPEX-2
Iron biogeochemistry in Antarctic pack ice during SIPEX-2
Our study quantified the spatial and temporal distribution of Fe and ancillary biogeochemical parameters at six stations visited during an interdisciplinary Australian Antarctic marine science voyage (SIPEX-2) within the East Antarctic first-year pack ice zone during September–October 2012. Unlike previous studies in the area, the sea ice Chlorophyll a, Particulate Organic Carbon and Nitrogen (POC and PON) maxima did not occur at the ice/water interface because of the snow loading and dynamic processes under which the sea ice formed. Iron in sea ice ranged from 0.9 to 17.4 nM for the dissolved (<0.2 µm) fraction and 0.04 to 990 nM for the particulate (>0.2 µm) fraction. Our results highlight that the concentration of particulate Fe in sea ice was highest when approaching the continent. The high POC concentration and high particulate iron to aluminium ratio in sea ice samples demonstrate that 71% of the particulate Fe was biogenic in composition. Our estimated Fe flux from melting pack ice to East Antarctic surface waters over a 30 day melting period was 0.2 µmol/m2/d of DFe, 2.7 µmol/m2/d of biogenic PFe and 1.3 µmol/m2/d of lithogenic PFe. These estimates suggest that the fertilization potential of the particulate fraction of Fe may have been previously underestimated due to the assumption that it is primarily lithogenic in composition. Our new measurements and calculated fluxes indicate that a large fraction of the total Fe pool within sea ice may be bioavailable and therefore, effective in promoting primary productivity in the marginal ice zone.
Sea ice, Iron, Antarctica, Southern Ocean, Primary production
111-122
Lannuzel, Delphine
20a53a4c-fb9a-42b7-b7d7-c32cf83da979
Chever, Fanny
a00eba82-6de3-4e4c-9017-544bcd8b5424
van der Merwe, Pier C.
1674a4a4-dd52-4f67-85f5-7cc875eb1dbe
Janssens, Julie
5fd180c5-6428-4ea5-8047-e2d2f85316f9
Roukaerts, Arnout
65392df5-e77d-4221-8a0d-f14af29999bd
Cavagna, Anne-Julie
3009e02c-2ea5-4527-8dc1-bf14afada658
Townsend, Ashley T.
cd6ddb1e-39c2-4496-ad26-6bec03bd5294
Bowie, Andrew R.
b693c3a6-8975-4095-ad4b-81a5a3bb1f29
Meiners, Klaus M.
64e59013-6e42-4797-b5e6-5a543c521934
Lannuzel, Delphine
20a53a4c-fb9a-42b7-b7d7-c32cf83da979
Chever, Fanny
a00eba82-6de3-4e4c-9017-544bcd8b5424
van der Merwe, Pier C.
1674a4a4-dd52-4f67-85f5-7cc875eb1dbe
Janssens, Julie
5fd180c5-6428-4ea5-8047-e2d2f85316f9
Roukaerts, Arnout
65392df5-e77d-4221-8a0d-f14af29999bd
Cavagna, Anne-Julie
3009e02c-2ea5-4527-8dc1-bf14afada658
Townsend, Ashley T.
cd6ddb1e-39c2-4496-ad26-6bec03bd5294
Bowie, Andrew R.
b693c3a6-8975-4095-ad4b-81a5a3bb1f29
Meiners, Klaus M.
64e59013-6e42-4797-b5e6-5a543c521934
Lannuzel, Delphine, Chever, Fanny, van der Merwe, Pier C., Janssens, Julie, Roukaerts, Arnout, Cavagna, Anne-Julie, Townsend, Ashley T., Bowie, Andrew R. and Meiners, Klaus M.
(2014)
Iron biogeochemistry in Antarctic pack ice during SIPEX-2.
Deep Sea Research Part II: Topical Studies in Oceanography, 131, .
(doi:10.1016/j.dsr2.2014.12.003).
Abstract
Our study quantified the spatial and temporal distribution of Fe and ancillary biogeochemical parameters at six stations visited during an interdisciplinary Australian Antarctic marine science voyage (SIPEX-2) within the East Antarctic first-year pack ice zone during September–October 2012. Unlike previous studies in the area, the sea ice Chlorophyll a, Particulate Organic Carbon and Nitrogen (POC and PON) maxima did not occur at the ice/water interface because of the snow loading and dynamic processes under which the sea ice formed. Iron in sea ice ranged from 0.9 to 17.4 nM for the dissolved (<0.2 µm) fraction and 0.04 to 990 nM for the particulate (>0.2 µm) fraction. Our results highlight that the concentration of particulate Fe in sea ice was highest when approaching the continent. The high POC concentration and high particulate iron to aluminium ratio in sea ice samples demonstrate that 71% of the particulate Fe was biogenic in composition. Our estimated Fe flux from melting pack ice to East Antarctic surface waters over a 30 day melting period was 0.2 µmol/m2/d of DFe, 2.7 µmol/m2/d of biogenic PFe and 1.3 µmol/m2/d of lithogenic PFe. These estimates suggest that the fertilization potential of the particulate fraction of Fe may have been previously underestimated due to the assumption that it is primarily lithogenic in composition. Our new measurements and calculated fluxes indicate that a large fraction of the total Fe pool within sea ice may be bioavailable and therefore, effective in promoting primary productivity in the marginal ice zone.
Text
1-s2.0-S0967064514003476-main.pdf
- Version of Record
Available under License Other.
More information
e-pub ahead of print date: 11 December 2014
Keywords:
Sea ice, Iron, Antarctica, Southern Ocean, Primary production
Organisations:
Ocean and Earth Science
Identifiers
Local EPrints ID: 402304
URI: http://eprints.soton.ac.uk/id/eprint/402304
ISSN: 0967-0645
PURE UUID: dbbca20f-6ec1-409c-b4fd-9a15d60efd91
Catalogue record
Date deposited: 03 Nov 2016 11:55
Last modified: 15 Mar 2024 03:13
Export record
Altmetrics
Contributors
Author:
Delphine Lannuzel
Author:
Fanny Chever
Author:
Pier C. van der Merwe
Author:
Julie Janssens
Author:
Arnout Roukaerts
Author:
Anne-Julie Cavagna
Author:
Ashley T. Townsend
Author:
Andrew R. Bowie
Author:
Klaus M. Meiners
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