Phytoplankton populations were low during a late March 1987 transect from Prydz Bay to Australia, with chlorophyll a concentrations ranging from 0.08 to 0.22 mg.m-3. The dataset, archived by the Australian Antarctic Data Centre, details the composition, size, and abundance of phytoplankton and microzooplankton, revealing that nanoplankton consistently made up 55 to 68% of total cell numbers. A five-fold increase in small flagellate abundance was observed at 47°S, while diatom numbers increased markedly south of the Antarctic Convergence.
Use Cases
- Model chlorophyll a concentration based on latitude and cell size fractions (nanoplankton, picoplankton, microplankton).
- Analyze the correlation between diatom abundance and silica concentration south of the Antarctic Convergence.
- Investigate the latitudinal variation in total cell volume, which was primarily driven by microplankton constituting 57 to 93% of volume.
- Study the relationship between pigment markers (e.g., peridinin, zeaxanthin) and specific phytoplankton groups like flagellates and cyanobacteria across the transect.
- Examine the co-variability of ciliate and tintinnid numbers, particularly their low abundance in the Antarctic Convergence region.
Strengths
- Includes specific concentration ranges for chlorophyll a (0.08 to 0.22 mg.m-3) and precise cell size fraction percentages.
- Provides detailed taxonomic and pigment analysis (HPLC) across a defined latitudinal transect.
- Documents a clear ecological boundary at the Antarctic Convergence with marked changes in species composition.
Limitations
- Single cruise from 1987 provides only a temporal snapshot with no time-series context.
- Sample size is limited to one transect, restricting spatial generalizability.
- Data is over 35 years old, limiting relevance to current ocean conditions without contemporary comparison.
Provenance
- Source
- Australian Antarctic Data Centre (AU_AADC), accessed via NASA Earthdata.
- Collection Method
- Field measurements and HPLC analysis from the Nella Dan research cruise.
- Time Range
- Late March 1987.
- Freshness
- Data reflects a single cruise concluding on 1987-03-23; no update frequency.
- Geography
- Ocean transect from Prydz Bay, Antarctica, to Australia.