Keyword

VOLUME

8 record(s)
 
Type of resources
Topics
Keywords
Contact for the resource
Provided by
From 1 - 8 / 8
  • This dataset contains hydroacoustic results from the Antarctic Division Biomass Experiment II (ADBEX II) cruise of the Nella Dan. This cruise is the third in a series of six cruises, performing a long term survey of krill and other zooplankton distribution and abundance. Australia was to have participated in the Second International Biomass Experiment I (SIBEX I), but withdrew due to resupply problems. ADBEX II is a reduced sampling program of what was to have been sampled during SIBEX I. Three transects were made off Antarctica in the Mawson region of the Australian sector, in January to March 1984, covering a survey area of 70,000 square kilometers. Quantitative and geographic krill distribution, abundance, mean and variance of the krill weight density, and total krill biomass were obtained. Biomass estimates for ADBEX II are given as 3.5 million tonnes, obtained by extrapolating over the survey area used on the SIBEX II cruise (1.28x10^6 square kilometers). Temperature, nutrient and salinty data were also obtained, as well as trawl results. Summary results are listed in the documentation. The fields in this dataset are: pressure temperature salinity volume geopotential samples deviation

  • Sea ice covers up to 20 million km2 of the Southern Ocean. When present it supports a vigorous ecosystem that provides energy and food for all other marine organisms. Using the latest micro sensor technology, we are examining the factors that effect the productivity of this vital link in the Antarctic marine food web. New data were added to this metadata record in January 2011. These data included FRRF data collected on the CEAMARC, CASO, SIPEX and SAZ-SENSE voyages. A word document in the download file provides details about these datasets, plus those collected on Voyage 1 2009-2010, and voyage 2 2008-2009. The download file also contains a folder labelled "Older data". This data is described below: An explanation of the excel spreadsheet in the download file is as follows: Worksheet 1 is the chlorophyll data Worksheet 3 is the location data CHLOROPHYLL DATA Column A is sample name, the first letter refers to the location data in worksheet 3, the second to the ice flow number and the third to the replicate number Section refers to depth in ice core, measured from the bottom Ignore C Column D is the total volume of melted ice Column E is the volume of D that was filtered Column G is the Fluorometer reading before the addition dilute HCl Column H is the fluorometer reading after the addition of acid Column I is the calculation of chlorophyl concentration in the sample Column K is areal chlorophyll estimate Column L is the mean for the core Column N is the mean for the site Column O is the standard deviation LOCATION DATA Lat, longs and times of each sampling. The first set (B-G) refers to the time sampling started, the second (H-M) to when it finished Project objectives: - Determine the net photosynthesis and primary productivity of the phytoplankton and major sea ice algal communities of the Eastern Antarctic Sea Ice Zone (SIZ). Estimate seasonal and annual algal production and inter annual variability - Obtain data on biomass distribution and variability to establish regional relationships between ice thickness, snow cover, and biomass - Determine the effects of a) Light b) Nutrients (principally nitrate and iron) c) Temperature on photosynthesis and primary production - Determine whether the biomass and productivity of the phytoplankton and sea ice algae in winter and spring limits the biomass or growth of krill - Estimate the effects of climate change on Sea ice Zone primary production Taken from the 2008-2009 Progress Report: Progress against objectives: This project used V2, a spring voyage, to collect underway data to determine surface biomass and primary production. Biomass samples (chlorophyll a) were taken every 3 hours. Productivity estimates by PAM were also made every 3 hours. Productivity measurements by FRRF were made every 1 minute. Nutrient samples were taken at the same time as the biomass samples. Analysis of the biomass samples is complete. Preliminary analysis of the productivity data has commenced. This data is being used for a Masters project (Rob Johnson, IASOS). An iron addition experiment accompanied this monitoring. Iron was added to samples taken every 3 hours and the change in photosynthesis (maximum quantum yield) measured with a PAM. The rate of recovery from iron stress was the principal focus. Most of this data has been submitted as metadata. Using The PAM and FRRF simultaneously also enabled a comparison to be made between these different ways of measuring photosynthesis. Progress was also made on the analysis of FRRF productivity and biomass data collected over several years on the L'Astrolabe transect. Analysis involves quantitative manipulation of FRRF data and correlation with chlorophyll, nutrients, temperature and other biological parameters. A publication arising from this work will be submitted this year. Taken from the 2009-2010 Progress Report: Progress against objectives: We participated in V1 of the Aurora Australis, spring 2009. The objective of this project was to measure surface primary production off East Antarctica. Photosynthetic parameters of phytoplankton under actinic light (L) as well as in darkness (D) were measured using a fast repetition rate fluorometer (FRRF). The parameters included the maximum photochemical efficiency (Fv/FmL,D), the functional absorption cross section of photosystem II (sPSII,L,D) and a turnover time of electron transfer (tL,D). Chlorophyll a concentration was measured by using Turner fluorometer. The photosynthetic parameters, irradiance and chlorophyll a concentration will then be used to estimate primary production of phytoplankton. This field program particularly focussed on the first of the listed objectives, ie 'Determine the net photosynthesis and primary productivity of the phytoplankton and major sea ice algal communities of the Eastern Antarctic Sea Ice Zone (SIZ). Estimate seasonal and annual algal production and inter annual variability'. We have been collecting FRRF-based primary production data from each season and the 2009 data provides the late spring data to supplement data from autumn, winter and summer, collected in previous seasons. We have now built up a comprehensive assessment of season variability which will enable a reliable estimate of annual primary production. These analyses will also provide a detailed snap shot of primary production with which to compare future changes. Preliminary analysis shows clear patterns of variation in Fv/Fm, a parameter that is particularly sensitive to low iron concentration. This data is shown on an accompanying diagram. Productivity analysis is still underway. Much of the work for this project forms part of the PhD project of Cheah Wee.Wee is expected to finish his PhD by December 2010 and it is anticipated that all data analysis for the project will have been completed and the finished manuscripts submitted for publication. He has already had one manuscript form this project accepted (Cheah et al, 2010).

  • This dataset contains the underway data from Voyage 6 1990-91 (AAMBER2) of the Aurora Australis. This was primarily a marine science voyage. DLS data types were logged at 60-second intervals. The observations were taken between January and March 1991 en route from Hobart to Prydz Bay to Mawson to Davis and back to Hobart. Marine Science Support Data Quality and Programmer's Reports are available via the Related URL section. Temperature and salinity data from the CTD were also obtained. The fields in the CTD dataset are: pressure temperature salinity volume geopotential

  • This dataset contains CTD (conductivity, temperature, depth) and nutrient (nitrate, nitrite, phosphate, silicate, manganese) data obtained from the Antarctic Division BIOMASS Experiment III (ADBEX III) cruise of the Nella Dan, during Sep - Dec 1985. This cruise is the fifth cruise out of a series of six, conducting a long term field survey on krill and other zooplankton. 50 CTD casts were taken in the Prydz Bay region, and nutrient data were collected at 25 of the stations. Casts were made to 2000 m or to near bottom over the continental shelf. The oceanographic and nutrient programs were subordinate to other programs and so the locations of the CTD stations were not always ideal for oceanographic purposes. The fields in this dataset are: pressure temperature salinity volume geopotential samples deviation conductivity

  • This thesis was conducted under the auspices of the Southern Ocean Continuous Plankton Recorder (CPR) Survey. The research conducted had the dual aims of providing baseline data for this long-term monitoring program and providing the first detailed analysis of zooplankton communities and distribution patterns in the Southern Ocean south of Australia. Data were principally collected between October 2001 and March 2002, during five voyages. As a primary step I investigated the sampling characteristics of CPR, and assessed the utility of the CPR as a long-term monitoring apparatus in the Southern Ocean. Given the shallow sampling depth of the CPR (~10.5m), a major requirement of this calibration was quantification of the fine-scale vertical distributions zooplankton. This was done through direct comparison of CPR samples with depth integrated NORPAC net hauls. The CPR-NORPAC comparison identified the component of the zooplankton sampled by the CPR and provided a means for comparison between past and present data sets. As a final component of this calibration, it was demonstrated that the CPR was effective at identifying biogeographic boundaries. An essential requirement for the identification of long-term ecological change is baseline data on natural ecosystem variability, particularly seasonality. Therefore, after calibration of the CPR the two fundamental components of spatial and seasonal variability were investigated. Firstly, the fine-scale horizontal structure of zooplankton communities was quantified from a 1170 nautical mile transect, along the 140oE meridian, spanning all of the major oceanographic zones south of Australia. Applying multivariate analyses a unique community zonation was identified which was strongly related to the complex oceanographic environment, characterised by multiple branches of the major fronts. The seasonal component of temporal variability was investigated separately in two major and distinctly different regions, the Seasonal Ice Zone and the Sub-Antarctic / Polar Frontal Zone. Multivariate analyses were used to quantify seasonal changes in species composition, Bray-Curtis dissimilarity, species densities, and the proportional contribution of species to communities. The spatial and temporal variation of zooplankton community structure was discussed in the light of environmental controls, species' vertical distributions, population cycles, and ecosystem functioning. Finally,the application of these data to long-term monitoring was discussed, and recommendations made for future research. The fields in this dataset are: CPR Segment Number Time (GMT) Date Latitude Longitude Segment Length (nautical miles) Salinity Sea Surface Temperature Species Fish Larvae Fish Scales Egg Mass Volume Bongo CTD Depth

  • This dataset contains CTD (conductivity, temperature, depth) and nutrient (nitrate, phosphate, silicate) data obtained from the Antarctic Division BIOMASS Experiment I (ADBEX I) cruise of the Nella Dan, during Nov - Dec 1982. This cruise is the second in a series of six, conducting a long term field survey of krill and other zooplankton. 79 CTD casts were taken in the Prydz Bay region, and nutrient data were collected at 28 out of the 79 CTD stations. Casts within the shelf zone were made to the bottom and down to 2000 m offshore. Oceanographic sampling was subordinate to other programs such as the phytoplankton survey, hence the locations of the CTD stations were not always ideal for oceanographic purposes. Nutrient samples were collected to provide information for the interpretation of phytoplankton distribution and abundance. The fields in this dataset are: Pressure temperature salinity volume geopotential samples deviation conductivity

  • Marine soft-sediment assemblages were sampled from shallow (5 - 35m) nearshore regions around Casey Station, Windmill Islands, East Antarctica in late summer (Feb-March) 1997, using a van-Veen grab (surface area 20 x 25 cm). Samples were sieved through a 1 mm mesh and sorted to species where possible. A hierarchical, spatially nested sampling design was used with locations (km's apart), sites (100s of metres apart), and plots (10s of m). Two potentially impacted, polluted locations (adjacent to a sewage outfall and an old garbage tip) were compared with two control locations. Data was analysed using both multivariate and univariate statistical methods. Significant differences in assemblages were found between locations and between sites within locations. Significant differences in the abundances of taxa at several taxonomic levels (species, family, order, phylum) were found at all three spatial scales. Significant differences were also detected between the polluted and control locations. Compared with other Antarctic locations, the assemblages were dominated by crustaceans (90 to 97 % of individuals) and there was a paucity of polychaete fauna at the locations sampled. This study represents the first description of benthic assemblages from this region. A total of 70 samples are included in this data set. Also links to ASAC 1100. The fields in this dataset are: Location Site Plot/replicate Weight Volume Species

  • State of the Environment bibliography, compiled by Ewan McIvor. Contains 51 records. The fields in this dataset are: author year journal title volume pages publisher place of publication copy on file URL keywords