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PAR

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  • This dataset contains digitized passive acoustic recordings from a hydrophone connected to an autonomous recording device both moored near the sea-floor in the Southern Ocean. Recordings were digitised at a sample rate of 500 Hz and were continuous over the period of operation. The intended purpose of these recordings was to collect baseline data on the acoustic environment (i.e. underwater sound fields). Underwater sounds that were recorded include sounds generated by Antarctic sea ice, marine mammals, and man-made sounds from ships and geo-acoustic surveys. Marine mammal sounds include calls from blue, fin, humpback, and minke whales.

  • This dataset contains digitized passive acoustic recordings from a hydrophone connected to an autonomous recording device both moored near the sea-floor in the Southern Ocean. Recordings were digitised at a sample rate of 500 Hz and were continuous over the period of operation. The intended purpose of these recordings was to collect baseline data on the acoustic environment (i.e. underwater sound fields). Underwater sounds that were recorded include sounds generated by Antarctic sea ice, marine mammals, and man-made sounds from ships and geo-acoustic surveys. Marine mammal sounds include calls from blue, fin, humpback, and minke whales. The data were collected in 2006 from a hydrophone deployed on a mooring in the Prydz Bay area.

  • This dataset contains digitized passive acoustic recordings from a hydrophone connected to an autonomous recording device both moored near the sea-floor in the Southern Ocean. Recordings were digitised at a sample rate of 500 Hz and were continuous over the period of operation. The intended purpose of these recordings was to collect baseline data on the acoustic environment (i.e. underwater sound fields). Underwater sounds that were recorded include sounds generated by Antarctic sea ice, marine mammals, and man-made sounds from ships and geo-acoustic surveys. Marine mammal sounds include calls from blue, fin, humpback, and minke whales. The hydrophone was deployed on a mooring on the Kerguelen Plateau.

  • This dataset contains digitized passive acoustic recordings from a hydrophone connected to an autonomous recording device both moored near the sea-floor in the Southern Ocean. Recordings were digitised at a sample rate of 500 Hz and were continuous over the period of operation. The intended purpose of these recordings was to collect baseline data on the acoustic environment (i.e. underwater sound fields). Underwater sounds that were recorded include sounds generated by Antarctic sea ice, marine mammals, and man-made sounds from ships and geo-acoustic surveys. Marine mammal sounds include calls from blue, fin, humpback, and minke whales. The data were collected in 2005 from a hydrophone deployed on a mooring in the Prydz Bay area.

  • This dataset contains digitized passive acoustic recordings from a hydrophone connected to an autonomous recording device both moored near the sea-floor in the Southern Ocean. Recordings were digitised at a sample rate of 500 Hz and were continuous over the period of operation. The intended purpose of these recordings was to collect baseline data on the acoustic environment (i.e. underwater sound fields). Underwater sounds that were recorded include sounds generated by Antarctic sea ice, marine mammals, and man-made sounds from ships and geo-acoustic surveys. Marine mammal sounds include calls from blue, fin, humpback, and minke whales. The hydrophone was deployed on a mooring on the Kerguelen Plateau in 2006.

  • The data comprise images (encapsulated postscript and PNG formats) showing the integrated solar irradiance exposure of sea ice. The exposure value for ice at a given grid point was calculated by computing the motion trajectory of that patch of ice across the autumn/winter season (1-March to 1-November). Daily motion data were obtained from the National Snow and Ice Data Center (http://nsidc.org/data/nsidc-0116.html). The integrated radiation exposure was then calculated using daily estimates of downward solar flux from the NCEP/NCAR re-analyses. The values shown in the images are cumulative photosynthetically active radiation expressed in W-days/m^2. Please contact the data custodian before using these data. This work was done as part of ASAC project 2943 (ASAC_2943). See the link below for public details about the project.

  • The actual piece of equipment used was an International Light IL 1700Radiometer equipped with broad band detectors to measure PAR, UV-A and erythemal UV-B. The effects of UV-B radiation on the fatty acid, total lipid and sterol composition and content of three Antarctic marine phytoplankton were examined in a preliminary culture experiment. Exponential growth phase cultures of the diatoms Odontella weissflogii and Chaetoceros simplex and the Haptophyte Phaeocystis antarctica were grown at 2 (plus or minus 1)degrees C and exposed to 16.3 (plus or minus 0.7) W.m-2 photosynthetically active radiation (PAR). UV-irradiated treatments were exposed to constant UV-A (4.39 (plus or minus 0.20) W.m-2) and low (0.37 W.m-2) or high UV-B (1.59 W.m-2). UV-B treatments induced species specific changes in lipid content and composition. The sterol, fatty acid and total lipid content and profiles for O. weissflogii changed little under low UV-B when compared with control conditions (PAR alone), but showed a decrease in the lipid content per cell under high UV-B treatment. In contrast, when P. antarctica was exposed to low UV-B irradiance, storage lipids were reduced and structural lipids increased indicating that low UV-B enhanced cell growth and metabolism. P. antarctica also contained a higher proportion of polyunsaturated fatty acids under low UV-B in comparison with PAR irradiated control cultures. The flagellate life stage of P. antarctica died under high UV-B irradiation. However, exposure of P. antarctica to high UV-B irradiance increased total lipid, triglyceride and free fat. The effect of UV-B irradiances on the lipid content of Antarctic marine phytoplankton is species specific. Changes in ambient UV-B may alter the nutritional quality of food available to higher trophic levels. EXPERIMENTAL All measurements of irradiance were made with an International Light IL 1700 Radiometer equipped with broad band detectors to measure PAR, UV-A and erythemal UV-B [14]. A National Institute of Standards and Technology intercomparison package (NIST Test #534/240436-88) was used to calibrate each light sensor. Unialgal cultures of the diatoms Odontella weissflogii and Chaetoceros simplex were isolated from sea ice collected in Prydz Bay, Antarctica during the 1990/91 austral summer. Phaeocystis antarctica was isolated from Prydz Bay in 1982/83 summer. Cultures of diatoms and Phaeocystis antarctica were maintained in 2 l glass flasks using f/2 growth medium [32] and GP5 medium [33] respectively at a temperature of 2 plus or minus 1 degrees C. Cool white fluorescent lights provided photosynthetically active radiation (PAR) intensity of 17.08 J.m-2.s-1 (84.7 micro E.m-2.s-1), with no UV-B enhancement, on a 12 h light : 12 h dark cycle. Immediately before experimental irradiation, three replicate subsamples of approximately 15 ml were obtained from each parental culture and fixed with Lugols iodine, a known sample volume sedimented, and cells counted over 15 replicate fields using a Labovert inverted microscope. Mean cell concentration and standard deviation were then computed. Each exponential growth phase parental culture was thoroughly mixed and 3 replicate 300 ml Costar polystyrene culture flasks (which completely absorbed wavelengths below 295 nm) established for each light treatment (control, low and high UV exposures). Cultures were irradiated for 24 hours in a 48 hour experimental period (6 h light : 12 h dark : 12 h light : 12 h dark : 6 h light) [14, 23]. Exposures were conducted in a Thermoline controlled environment cabinet at 2 plus or minus 1 degrees C with cool white fluorescent tubes to provide PAR and UV-A (320-400 nm), with UV-B provided by FS20T 12 UV-B Westinghouse sunlamps. PAR and UV-A irradiances were 16.3 plus or minus 0.7 W.m-2 (81.3 plus or minus 3.4 micro E.m-2.s-1) and 4.39 plus or minus 0.20 W.m-2 respectively. The spectral distribution and UV-B irradiance were varied by attenuation with glass filters [5] to provide low (0.37 W.m-2) or high UV-B (1.59 W.m-2). Sensors were each covered by an attenuating glass screen and a single layer of Costar culture flask to measure the experimental irradiances to which the algae were exposed. UV-B irradiances were chosen to reflect less than (74%) and greater than (318%) peak UV-B exposure as measured at an Antarctic coastal site (Casey station, 66 degrees S, [34]). Following irradiation each culture was well mixed and approximately 15 ml was fixed with Lugols Iodine for subsequent estimation of cell concentration (as above). Chlorotic and greatly vesicularised cells were considered to be dead [23]. The remainder of each experimental culture was filtered through Whatman GF/F filters. On completion of filtration, the filters were stored at -20C overnight before extraction of lipids the following day.

  • Data collected from O'Gorman rocks near Davis Station between February 2004 to January 2005. Data were collected using a Yellow Science Industries 6600 Sonde. Vertical profiles of Temperature, Salinity, Conductivity, Dissolved Oxygen, Photosynthetically Active Radiation were collected. Each Sampling date/time and depths were recorded. The data are stored in spreadsheet form, and saved as a comma separated values text file. This work was carried out as part of ASAC project 40. The fields in this dataset are: Date Time Temperature Conductivity Salinity Dissolved Oxygen Depth Photosynthetically Active Radiation

  • A collection of about 20 isolates of Antarctic microalgae from the Windmill Islands region, around Casey Station has been established in the University of Malaya Algae Culture Collection (UMACC). The Antarctic microalgae in the collection includes Chlamydomonas, Chlorella, Stichococcus, Navicula. Ulothrix and Chlorosarcina. Comparative studies on the effect of global warming and UVR stress on these Antarctic microalgae and the tropical collection are being conducted. From the abstract of one of the referenced papers: The growth, biochemical composition and fatty acid profiles of six Antarctic microalgae cultured at different temperatures, ranging from 4, 6, 9, 14, 20 to 30 degrees C, were compared. The algae were isolated from seawater, freshwater, soil and snow samples collected during our recent expeditions to Casey, Antarctica, and are currently deposited in the University of Malaya Algae Culture Collection (UMACC). The algae chosen for the study were Chlamydomonas UMACC 229, Chlorella UMACC 234, Chlorella UMACC 237, Klebsormidium UMACC 227, Navicula UMAC 231 and Stichococcus UMACC 238. All the isolates could grow at temperatures up to 20 degrees C; three isolates, namely Navicula UMACC 231 and the two Chlorella isolates (UMACC 234 and UMACC 237) grew even at 30 degrees C. Both Chlorella UMACC 234 and Stichococcus UMAC 238 had broad optimal temperatures for growth, ranging from 6 to 20 degrees C (growth rate = 0.19 - 0.22 per day) and 4 to 14 degrees C (growth rate = 0.13 - 0.16 per day), respectively. In constrast, optimal growth temperatures for Navicula UMACC 231 and Chlamydomonas UMACC 229 were 4 degrees C (growth rate = 0.34 per day) and 6 to 9 degrees C (growth rate = 0.39 - 0.40 per day), respectively. The protein content of the Antarctic algae was markedly affected by culture temperature. All except Navicula UMACC 231 and Stichococcus UMACC contained higher amount of proteins when grown at low temperatures (6-9 degrees C). The percentage of PUFA, especially 20:5 in Navicula UMACC 231 decreased with increasing culture temperature. However, the percentages of unsaturated fatty acids did not show consistent trend with culture temperature for the other algae studied. There are three spreadsheets available in the download file. ASAC_2590 - provides detail about where each species of algae was collected from. ASAC_2590a - provides data from Teoh Ming-Li et al (2004) ASAC_2590b - provides data from Wong Chiew-Yen et al (2004) The fields in this dataset are: Isolate Culture Collection number Origin (Location) Fatty acids saturated fatty acids polyunsaturated fatty acids monounsaturated fatty acids Temperature growth rate PAR UVB

  • 1. In situ chlorophyll fluorescence measurements using pulse amplitude technique (PAM) of macroalga Desmarestia menziesii, assessing adaptation to high light exposure after sea ice breakout, and impact of Thala Valley tip wastes. 2. In situ chlorophyll fluorescence measurements using pulse amplitude technique (PAM) of sediment diatom material assessing adaptation to high light exposure after sea ice breakout, and impact of Thala Valley tip wastes. 3. In situ chlorophyll fluorescence measurements using pulse amplitude technique (PAM) of sponge Latrunculia decipiens assessing adaptation to high light exposure after sea ice breakout. 4. Ecotoxicological experiments where Desmarestia menziesii was exposed to copper in indoor aquaria, aim to determine EC50, NOEC, LOEC for copper. 5. Field collections of various macroalgae for stable isotope analysis: for determination of physiological mechanisms. 6. Field collections of sponge and diatom material for pigment analysis.