Phytoplankton Data Collected During CPR Tows of the Southern Ocean - Australian Antarctic Division Copy
This is an Australian Antarctic Division version of a metadata record on the IMOS portal, detailing the AADs contribution to the project. For further details about the data, and access to the data itself, see the metadata record at the Point of Truth URL. Data are "phytoplankton counts" fo...
| Summary: | This is an Australian Antarctic Division version of a metadata record on the IMOS portal, detailing the AADs contribution to the project. For further details about the data, and access to the data itself, see the metadata record at the Point of Truth URL. Data are "phytoplankton counts" for each phytoplankton taxon observed, from the CPR samples collected by the Southern Ocean CPR Survey projects 472 and 4107 (Hosie et al. 2003). The SAHFOS on-silk phytoplankton count method is used (Batten et al. 2003). Phytoplankton are identified to the best taxonomic level possible, ideally to species or at least genus, in 20 fields of view (295 plus or minus 10 microns) per sample (section of silk). See Figure 2 of Batten et al. (2003). Each sample usually represents 5 nautical miles for SO-CPR. The "phytoplankton count" is the number of fields of view where a phytoplankton species/ taxon was observed, recorded for each taxon for each sample. It is effectively a frequency of occurrence score. The CPR is a device towed at normal ship speed, approximately 100 m behind the ship at a depth of 8-10 m. Plankton enter a small aperture 12.7 x 12.7 mm which then expands into a tunnel 100 x 50 mm reducing the speed by about 1/30. Plankton are then sandwiched between two sheets of 270 micron silk gauze, before rolling into a preservation tank of formaldehyde. Each tow is approximately 450 nautical miles. Regardless of ship speed the silk advances at a fixed rate of about 1 cm per nautical mile. Silks are cut into 5 nautical mile equivalent lengths and both phyto- an zooplankton are counted. Each sample is coded with time and date (GMT) and latitude and Longitude, plus averaged environmental data over the 5 nautical miles, e.g. water temperature, salinity, fluorescence, light. Zooplankton data and methods are described in Metadata record AADC-00099. Abbreviations CPR, Continuous Plankton Recorder SAHFOS, Sir Alister Hardy Foundation for Ocean Science SO-CPR , Southern Ocean CPR Survey |
|---|