AMT12 Pico-plankton, nano-plankton and bacteria abundance from AFC analysis of samples collected from CTD bottle samples
Originator's Protocol for Data Acquisition and Analysis
This dataset originates from analyses on samples collected from CTD casts during the cruise. Samples were frozen for analysis after the cruise.
Unstained samples were analysed by flow cytometry after the cruise. Prochlorococcus spp. and Synechococcus spp. (cyanobacteria), picoeukaryotes and heterotrophic bacteria were characterised and enumerated based on their light scattering and autofluorescence properties. Further details can be found in Heywood et al. (2006).
References Cited
Heywood J.L., Zubkov M.V., Tarran G.A., Fuchs B.M. and Holligan P.M., 2006. Prokaryoplankton standing stocks in oligotrophic gyre and equatorial provinces of the Atlantic Ocean: Evaluation of inter-annual variability. Deep-Sea Research Part II, 53, 1530-1547.
Instrumentation Description
Becton Dickinson FACSort instrument
BODC Data Processing Procedures
Data were submitted via email in two Excel spreadsheets archived under BODC's accession number SOC040144. One spreadsheet contained the Prochlorococcus spp., Synechococcus spp. and picoeukaryotes data, the second contained the heterotrophic bacteria abundances. Sample metadata (CTD number, latitude and depth) were checked against information held in the database. There were no discrepancies in the metadata provided and that held in the database.
The data were provided in cell abundance per millilitre. These units were consistent with the BODC parameter code units and no conversions were necessary. After discussion with the data originator BODC were advised the Prochlorococcus data were in error by a factor of 10. These data were reduced by a factor of 10 before loading to the database.
The data were reformatted and loaded in BODC's samples database under Oracle Relational Database Management System. Data were marked up with BODC parameter codes and loaded into the database. Individual samples were matched through rosette sampling bottle and depth.
A parameter mapping table is provided below;
| Originator's Parameter | Units | Description | BODC Parameter Code | Units | Comments |
|---|---|---|---|---|---|
| Synechococcus spp. | cell abundance ml -1 | Abundance of Synechococcus spp. (ITIS: 773: WoRMS 160572) per unit volume of the water body by automated flow cytometry | P700A90Z | cell abundance ml -1 | n/a |
| Prochlorococcus spp. | cell abundance ml -1 | Abundance of Prochlorococcus spp. (ITIS: 610076: WoRMS 345515) per unit volume of the water body by automated flow cytometry | P701A90Z | cell abundance ml -1 | n/a |
| Pico-eukaryote phytoplankton (<2 µm) | cell abundance ml -1 | Abundance of Picoeukaryotic cells per unit volume of the water body by automated flow cytometry | PYEUA00A | cell abundance ml -1 | n/a |
| Heterotrophic bacteria | cell abundance ml -1 | Abundance of Bacteria (ITIS: 202421: WoRMS 6) [Subgroup: heterotrophic] per unit volume of the water body by automated flow cytometry and subtraction of Synechococcus+Prochlorococcus from total bacteria | HBCCAFTX | cell abundance ml -1 | n/a |
Data Quality Report
The data originator advised that these flow cytometry data are not considered to be of high quality, since samples were frozen and quickly analysed a while after the cruise.
Problem Report
Not relevant to this data set.
