The role of iron as a micro-nutrient to the Antarctic sea-ice zone algal community

Metadata record for data from AAS (ASAC) project 3026.

Public

This project will assess the importance of the trace micro-nutrient element iron to Antarctic sea-ice algal communities during the International Polar Year (2007-2009). We will investigate the biogeochemistry of iron, including a comprehensive examination of its distribution, speciation, cycling and role in fuelling ice-edge phytoplankton blooms. A significant part of this research will concentrate on the the influence of organic exopolysaccharides on iron solubility, complexation and bioavailability, both within the ice and in surrounding snow and surface seawater. This innovative research will improve our understanding of key processes that control the productivity of the climatically-important Antarctic sea-ice zone.

Project objectives:

This project will assess the importance of the trace element iron (Fe) as a micro-nutrient to seasonal sea-ice algal communities in the Australian sector of Antarctica during the International Polar Year (2007-09). We will investigate the biogeochemistry of Fe, including a comprehensive examination of its distribution, speciation, cycling and role in fuelling ice-edge phytoplankton blooms. A significant part of this research will concentrate on the influence of organic exopolysaccharides (EPS) on Fe solubility and complexation (and hence bioavailability), both within the ice and in surrounding surface waters. This innovative research will improve our understanding of key processes that control the productivity of the climatically-important Antarctic sea-ice zone.

Specifically, in this project:

- The biogeochemical behaviour of Fe in sea-ice with regards to EPS complexation, and key physicochemical and biological data will be evaluated.

- The bioavailability of Fe for phytoplankton growth during sea-ice melt will be investigated through laboratory-based experiments designed to mimic spring conditions.

- The distribution of other bioactive trace elements in the Antarctic sea-ice environment will be examined as a means of fingerprinting the source(s) of Fe, as well as indicating their biological requirement.

Taken from the 2008-2009 Progress Report:

Progress against objectives:

In the last twelve months we achieved all the objectives planned for the shore-based sample processing and analysis from the SIPEX voyage (fieldwork September-October 2007). An extensive and unique seasonal and spatial data set was put together including parameters such as ice texture, salinity, temperature, Chlorophyll a, particulate organic carbon (POC), dissolved

organic carbon (DOC), macro-nutrients (silicate, phosphate and nitrate), and exoplysaccharides (EPS, using both alcian blue and PSA methods). Dissolved iron (dFe) and total dissolvable iron (TDFe) were analysed by flow injection - chemiluminescence (FIA-CL) analysis in Hobart. Polycarbonate (PC) filters (Nuclepore 0.2 micron pore size) retaining particulate metals were digested

in a mixture of strong, ultrapure acids (750 micro litre 12N HCl, 250 micro litre 40% HF, 250 micro litre 14N HNO3) on a hotplate at 125 degrees C for 8 h. The procedure was successfully applied to plankton, estuarine and river sediment reference materials to verify the recovery of the digestion treatment. The concentrations of particulate iron (PFe) were determined by high resolution ICP-MS at the Central Science Laboratory at UTAS. This data has been quality-controlled, analysed, interpreted and published (see below).

Due to the fact that logistical support was not possible for 2008/09 (insufficient berths at Casey Station) despite approval of our project, the field component of the project was delayed.

Taken from the 2009-2010 Progress Report:

Progress against objectives:

Monthly Milestones of PhD student Pier van der Merwe:

Successful Antarctic research expedition occurred in Oct-Dec 2009 at Casey Station Antarctica with logistical support from AAS project #3026 (flight on FA02 and berths at Casey station as well as field support of personnel).

OCT-DEC 2009 - Antarctic time series data collection and processing successful. Data analysis scheduled for Jan - Mar. Write up of last paper(s) scheduled for Mar-June. Final completion of thesis due in August.

DEC - Chlorophyll a data analysed

JAN - FIA and CLECSV analyses start simultaneously

FEB - Finish FIA analyses and attend Ocean science meeting in Portland Oregon.

MAR - Finish CLECSV analyses and run POC and PFe digestions and analyses. Scheduled with Thomas Rodemann and Ashley Townsend at the CSL, UTAS.

APR - MAY Data analysis and write up of 3rd paper, and possibly 4th based on field work at Casey station Oct-Dec 2009.

See the child metadata records for more information about the data.

Identification info

Alternate title: The role of iron as a micro-nutrient to the Antarctic sea-ice zone algal community

Date (Publication): 2009-04-27

Edition: 1

Originator

Trull, T.W.

Publisher

Australian Antarctic Data Centre

Principal investigator

TRULL, THOMAS WILLIAM

Antarctic CRC University of Tasmania

GPO BOX 252-80

Hobart

Tasmania

7001

Australia

+61 3 6226 2988

+61 3 6226 2973 (facsimile)

Collaborator

TRULL, THOMAS WILLIAM

Antarctic CRC University of Tasmania

GPO BOX 252-80

Hobart

Tasmania

7001

Australia

+61 3 6226 2988

+61 3 6226 2973 (facsimile)

Name: CAASM Metadata

Website: https://data.aad.gov.au/metadata/records/ASAC_3026

Status: Completed

Custodian

AU/AADC > Australian Antarctic Data Centre, Australia - AADC, DATA OFFICER (DATA CENTER CONTACT)

Australian Antarctic Division

203 Channel Highway

Kingston

Tasmania

7050

Australia

+61 3 6232 3244

+61 3 6232 3351 (facsimile)

Topic category

Biota
Environment
Oceans

Extent

Description: Temporal Coverage

Temporal extent

TimePeriod: 2007-09-11 2010-03-31

Title: Iron fractionation in pack and fast ice in East Antarctica: temporal decoupling between the release of dissolved and particulate iron during spring melt.

Date (Publication): 2011

Citation identifier: 58

Citation identifier: doi:10.1016/j.dsr2.2010.10.036

Author

van der Merwe, P., Lannuzel, D., Bowie, A., Mancuso Nichols, C. and Meiners, K.

Name: Deep Sea Research Part II Topical Studies in Oceanography

Issue identification: 9-10

Page: 1222-1236

Title: Biogeochemical observations during the winter-spring transition in East Antarctic sea ice: evidence of iron and exopolysaccharide controls.

Date (Publication): 2009

Citation identifier: 115

Author

van der Merwe, P., Lannuzel, D., Mancuso Nichols, C., Meiners, K., Heil, P., Norman, L., Thomas, D.N. and Bowie, A.

Name: Marine Chemistry

Page: 163-175

Title: The characteristics of dissolved organic matter (DOM) and chromophoric dissolved organic matter (CDOM) in Antarctic sea ice.

Date (Publication): 2011

Citation identifier: 58

Citation identifier: doi:10.1016/j.dsr2.2010.10.030

Author

Norman, L., Thomas, D.N., Stedmon, C.A., Granskog, M.A., Papadimitriou, S., Krapp, R.H., Meiners, K., Lannuzel, D., van der Merwe, P. and Dieckmann, G.

Name: Deep Sea Research Part II Topical Studies in Oceanography

Page: 1075-1091

Title: Dissolved and particulate metals in Antarctic sea ice and their role in tracing Fe sources

Date (Publication): 2010

Author

Lannuzel D., Bowie A.R., van der Merwe P., Townsend A., and Schoemann V.

Name: Marine Chemistry

Title: Size fractionation of trace metals during a time series in land-fast ice, Antarctica.

Date (Publication): 2010