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  • The composition, size and abundance of phytoplankton and microzooplankton were measured across a transect from Prydz Bay to Australia during late March 1987. Phytoplankton populations were low, with concentrations of chlorophyll a ranging from 0.08 to 0.22 mg.m-3. Small cells predominated numerically; nanoplankton consistently represented 55 to 68% of the total cell number while picoplankton represented 27 to 44%. Microplankton never represented more than 3% of cells by number, but constituted 57 to 93% of the total cell volume, and accounted for most of the latitudinal variation in total volume. Small flagellates, not identifiable by light microscopy, were the most numerous cells encountered across the transect, with a five-fold increase in abundance at 47S. Numbers of diatoms (most less than 20 microns in size) increased markedly south of the Antarctic Convergence, with a strong correlation to the concentration of silica. Dinoflagellate numbers were relatively constant across the transect, although somewhat higher north of 50S. Those less than 20 microns in size were most numerous and accounted for most of the numerical variation. HPLC analysis of chlorophyll and carotenoid pigments showed a peak of peridinin which coincided with the flagellate peak at 47S, but not with observed dinoflagellates, suggesting that the flagellate peak included unrecognized dinoflagellates. Chlorophyll b and prasinoxanthin were also associated, suggesting a significant contribution by prasinophytes. Almost no cyanobacteria were observed south of the convergence, although very large numbers, which correlated with the abundance of zeaxanthin, were encountered to the north. Numbers of ciliates and tintinnids were quite variable although they followed each other closely. Numbers of both were low in the region of the Antarctic Convergence.

  • Chlorophyll data was used to measure growth rates of sea ice algae in CO2 incubations. Sea ice brine microalgae was collected from sackholes. Replicate samples were incubated in ambient air (~0.04% CO2), 0.1% CO2, 1.0% CO2 and 2.0% CO2 concentrations. AT the end of the incubations the 50 ml samples were filtered through a 25 mm GF/F filter using vacuum filtration. The filters were placed in 15 ml plastic falcon tubes containing 10 ml of methanol, covered in aluminium foil and kept in the dark at 4 degrees C for 12 hours. Chl a concentration was measured using a 10AU Turner fluorometer following the acidification method of Strickland and Parsons (1972). Data in spread sheet shows the extracted chl + phaeophytin, phaeophytin and chlorophyll concentrations (micro grams l-1) for each of the three experiments. Data were collected at SIPEX Ice Stations 1-8 and SIPEX CTD stations 2-5

  • Chloropyll a data were collected on voyage 4 of the Aurora Australis, during the 1991-1992 season. These data were collected as part of ASAC project 40 (ASAC_40) (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

  • Chloropyll a data were collected along the WOCE transect on voyage 1 of the Aurora Australis, during October of 1991. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

  • This dataset contains chlorophyll a data collected by the Aurora Australis on Voyage 2, 1997-1998 - the ONICE cruise. Samples were collected from September-November of 1997. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

  • This dataset contains the chlorophyll a data from Voyage 6 (FISHOG) 1991-92 of the Aurora Australis. The observations were taken from the Heard Island area in January and February 1992. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

  • Chlorophyll a data collected on the AAMBER II cruise of the Aurora Australis from January to March of 1991. The voyage traveled to the Prydz Bay region, and data were collected en route and in the area.

  • This dataset contains chlorophyll a data collected by the Aurora Australis on Voyage 7, 1992-1993 - the WOES (Wildlife Oceanography Ecosystem Survey) cruise. Samples were collected from March-May of 1993. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

  • This dataset contains chlorophyll a data collected by the Aurora Australis on Voyage 6, 1997-1998 - the SAZ (Subantarctic Zone) cruise. Samples were collected in March of 1998. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).

  • This dataset contains chlorophyll a data collected by the Aurora Australis on Voyage 7 1992-93, taken in the Prydz Bay region between January and February 1993. These data were collected as part of ASAC project 40 (The role of antarctic marine protists in trophodynamics and global change and the impact of UV-B on these organisms).