TemperateReefBase Geonetwork Catalogue
Carbon isotopic signal of cholesterol and brassicasterol (respectively zooplankton and phytoplankton indicator) and presence of particulate Barium in the Antarctic sea-ice - collected during SIPEX II, 2012
Overview of the project and objectives:
Sea-ice phytoplankton is significantly enriched in 13C (delta 13C-POC) compared to pelagic phytoplankton in adjacent open waters because of carbon limitation in the brine pockets and due to physiological properties such as the presence of Carbon Concentrating Mechanisms (CCM) and/or the uptake of bicarbonate (HCO3-). Melting of sea-ice with release of sea-ice phytoplankton occurs during the growth season, so these isotopically heavy particles, if sinking out of the surface waters, can be expected to be found deeper in the water column. One hypothesis is that the natural carbon isotopic signal of brassicasterol (phytosterol, mainly diatom indicator) in the south Antarctic Bottom Water (AABW), a water mass which is influenced by the Seasonal Ice Zone (SIZ), is enriched compared to northern deep waters signal due to an enhanced contribution of sea-ice diatoms. The objective of this dataset acquisition is to gain information on the delta 13C signal of brassicasterol in sea-ice diatoms and further estimate the contribution of sea-ice algae release in the Southern Ocean biological pump.
In the course of the expedition, a second choice has been done to look at the presence of particulate barium in the sea-ice. In the open ocean, presence of particulate barium in the mesopelagic layer is an indicator of remineralisation process. The main idea is that marine snow composed of detritical organic matter (aggregates, faecal pellets, etc.) provides micro-environment favorable for precipitation of excess Barium or Baxs (total particulate Ba minus the lithogenic part; mainly constituted of barite crystals, BaSO4): is there such Baxs components in the sea-ice?
Methodology and sampling strategy:
Sampling strategy follows ice stations deployment via Bio ice-core type. Most of the time we worked close to / directly on the Trace Metal site following precautions concerning TM sampling (clean suits etc.). When we worked close to the TM site, precautions were not such important because we don't need the same drastic precautions for our own sampling. We work together because we want to propose a set of data which helps to characterize the system of functioning in close relation with TM availability (for that, sampling location have to be as close as possible). Ice melted from ice-core sections (see attached files for more details) is filtered on precombusted GF-F filters (0.7 microns porosity) and filters are stored at -20 degrees C. For particulate Barium sampling, same protocol but filtration on PC filters 0.4 microns, dry over night and store at ambient temperature.
At home laboratory (VUB, Brussels, Belgium), sterols samples are analysed via Gas Chromatography - Mass Spectrometer (GC-MS) and Gas Chromatography-combustion column-Isotope Ratio Mass Spectrometer (GC-c-IRMS) after chemical treatment. Barium sample are analysed via Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES).
Simple
Identification info
- Alternate title
- Carbon isotopic signal of cholesterol and brassicasterol (respectively zooplankton and phytoplankton indicator) and presence of particulate Barium in the Antarctic sea-ice - collected during SIPEX II, 2012
- Date (Publication)
- 2013-05-08
- Edition
- 1
Originator
Publisher
Principal investigator
Principal investigator
Principal investigator
Principal investigator
Collaborator
Collaborator
Collaborator
Collaborator
- Name
- CAASM Metadata
- Status
- Completed
Custodian
- Topic category
-
- Oceans
Extent
))
Extent
- Description
- Temporal Coverage
Temporal extent
- TimePeriod
- 2012-09-25 2012-11-01
- NASA/GCMD Earth Science Keywords
-
- EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > PROTISTS > PLANKTON > PHYTOPLANKTON
- EARTH SCIENCE > BIOSPHERE > ECOSYSTEMS > AQUATIC ECOSYSTEMS > PLANKTON > PHYTOPLANKTON
- EARTH SCIENCE > BIOSPHERE > ECOSYSTEMS > AQUATIC ECOSYSTEMS > PLANKTON > ZOOPLANKTON
- EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > NUTRIENTS
- Keywords
-
- Sterols
- NASA/GCMD Earth Science Keywords
-
- CORING DEVICES
- NASA/GCMD Earth Science Keywords
-
- R/V AA > R/V Aurora Australis
- LABORATORY
- NASA/GCMD Earth Science Keywords
-
- AMD
- CEOS
- ACE/CRC
- AMD/AU
- NASA/GCMD Earth Science Keywords
-
- OCEAN > SOUTHERN OCEAN
- GEOGRAPHIC REGION > POLAR
Resource constraints
- Use limitation
- This metadata record is publicly available.
Resource constraints
- Access constraints
- licence
- Other constraints
- These data are linked to the parent record SIPEX_II_Stable_Isotopes
Resource constraints
- File type
- Portable Network Graphic
- Title
- Attribution 4.0 International (CC BY 4.0)
- Website
-
https://creativecommons.org/licenses/by/4.0/legalcode
Legal code for Creative Commons by Attribution 4.0 International license
- Use constraints
- licence
- Other constraints
- This data set conforms to the CCBY Attribution License (http://creativecommons.org/licenses/by/4.0/). Please follow instructions listed in the citation reference provided at http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=SIPEX_II_Stable_Isotopes_Sterols when using these data.
- Language
- English
- Character encoding
- UTF8
Distribution Information
Distributor
Distributor
- OnLine resource
-
PROJECT HOME PAGE
Public information for ASAC project 4051
- OnLine resource
-
PROJECT HOME PAGE
Public information for ASAC project 4073
- OnLine resource
-
VIEW RELATED INFORMATION
Citation reference for this metadata record and dataset
Resource lineage
- Statement
- Each eventual parameter important for global comprehension of the dataset is highlighted as comment, when needed, in the Final Sample List.xls file (see parent record).
- Hierarchy level
- Dataset
- Maintenance and update frequency
- As needed
- Maintenance note
- 2013-05-09 - record created by Dave Connell from a template completed by Anne-Julie Cavagna. 2019-07-15 - record updated by Dave Connell - basic updates.
Metadata
- Metadata identifier
- string/SIPEX_II_Stable_Isotopes_Sterols
- Language
- English
- Character encoding
- UTF8
Author
Sponsor
Owner
- Title
- Parent Metadata Record
- Citation identifier
- SIPEX_II,SIPEX_II_Stable_Isotopes
Type of resource
- Resource scope
- Dataset
Alternative metadata reference
- Title
- gov.nasa.gsfc.gcmd
- Citation identifier
- 36615eda-e524-4406-9fe9-91b53acd5daa
Alternative metadata reference
- Title
- gov.nasa.gsfc.gcmd
- Date (Last Revision)
- 2019-07-15T14:55:21
Identifier
- Description
- metadata.extraction_date
Alternative metadata reference
- Title
- gov.nasa.gsfc.gcmd
- Citation identifier
- 8.6
- Metadata linkage
-
http://data.aad.gov.au/metadata/records/SIPEX_II_Stable_Isotopes_Sterols
Point of truth for the metadata record
- Date info (Creation)
- 2013-05-09T00:00:00
- Date info (Last Update)
- 2019-07-15
Metadata standard
- Title
- ISO 19115-3
- Edition
- 2014
- Other citation details
- Version 1
- Title
- DIF to ISO 19115-1 Profile
Overviews
Spatial extent
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