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TCO2 fluxes and pools for sediments in Jervis Bay, NSW (June and August 2008 and February 2009)Note: This metadata describes the dataset in accordance with the ANZLIC (Australia New Zealand Land Information Council) Core Metadata Guidelines Version 2. Dataset citationANZLIC unique identifier: ANZCW0703016218 Title: TCO2 fluxes and pools for sediments in Jervis Bay, NSW (June and August 2008 and February 2009) CustodianCustodian: Geoscience Australia Jurisdiction: Australia DescriptionAbstract: Geoscience Australia carried out marine surveys in Jervis Bay (NSW) in 2007, 2008 and 2009 (GA303, GA305, GA309, GA312) to map seabed bathymetry and characterise benthic environments through colocated sampling of surface sediments (for textural and biogeochemical analysis) and infauna, observation of benthic habitats using underwater towed video and stills photography, and measurement of ocean tides and wavegenerated currents. Data and samples were acquired using the Defence Science and Technology Organisation (DSTO) Research Vessel Kimbla. Bathymetric mapping, sampling and tide/wave measurement were concentrated in a 3x5 km survey grid (named Darling Road Grid, DRG) within the southern part of the Jervis Bay, incorporating the bay entrance. Additional sampling and stills photography plus bathymetric mapping along transits was undertaken at representative habitat types outside the DRG. This 126 sample data set comprises TCO2 flux and pool data for surface seabed sediments (~0 to 2 cm). ANZLIC search words:
Spatial domain:
Geographic extent name: AUSTRALIA EXCLUDING EXTERNAL TERRITORIES - AUS - Australia - Australia Geographic extent polygon: 150.6773 -35, 150.78 -35, 150.78 -35.13, 150.6773 -35.13, 150.6773 -35, Note: The format for each Geographic extent name is: Name - Identifier - Category - Jurisdiction (as appropriate) See GEN Register
Data currencyBeginning date: 2008-06-23 Ending date: 2009-02-13 Dataset statusProgress: Complete Maintenance and update frequency: Not Known Access
Access constraints: This material is released under the Creative Commons Attribution 3.0 Australia Licence. Free Data DownloadData qualityLineage: Bottom sediments were collected using a small Shipek type grab sampler.This device can collect an intact sample of sediment up to 5 cm by 12 cm in area and 5 cm thick. Upon triggering, the grab immediately covers the sample, which prevents washout of fine sediment during retrieval to the surface. Immediately after the grab was back aboard, the surface sediments were spooned into two 58 ml falcon vials for the vial incubation experiments. No later than 4 hours after collection, the porewaters from one of the two falcon vials (time = zero (t0)) were extracted by centrifugation (8890 rpm; 5 minutes) and syringefiltered (0.45 um) into 3 ml containers that had been precharged with 0.025 ml of mercuric chloride. Approximately 24 hours later, the second of the two falcon vials from each site (time = one (t1)) were sampled by the same method. The porewater extracts were stored in the refrigerator prior to analysis for TCO2 concentrations.These concentrations were measured at Geoscience Australia using an AS_C3 DIC analyser (Apollo SciTech), with a certified reference material as a standard.The TCO2 flux measurements represent the amount of CO2 produced by incubating sediment over a ~24 hour period, normalised to the volume of sediment used in the incubation. The TCO2 pool measurements constitute the TCO2 concentrations of the t=0 sample corrected for the TCO2 efflux during the period (up to 4 hours) prior to centrifugation, and normalised to the volume of incubating sediment. Positional accuracy: A C-NAV system was used to provide geographical position with a manufacturer accuracy of 10 cm RMS. However, the instruments may have been dragged by currents such that the readings may deviate from the GIS position. Attribute accuracy: Moderate. The average precision and accuracy (one standard deviation) of the TCO2 analyses were 0.2 ( 0.1) and 1.0% ( 0.4%) respectively. More error would be introduced when normalising with sediment volumes as there would be errors associated with these estimates. It is also worth mentioning that the t=0 and t=1 samples are from different samples take from the same grab so that sediment heterogeneity might have some bearing on the results. Logical Consistency: The same data acquisition procedures and laboratory processing were used for the three surveys that contributed to this dataset. Completeness: completed Contact information
Metadata informationMetadata date: 2013-03-08 Additional metadataMetadata reference XHTML: http://www.ga.gov.au/meta/ANZCW0703016218.html Metadata reference XML: http://www.ga.gov.au/meta/ANZCW0703016218.xml . Authors:Radke, L. |
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