AMT13 pigment composition by HPLC analysis from CTD bottle samples
Data Acquisition and Analysis
Fresh seawater samples from upto five light depths were collected from 57 stations during the cruise. The main sampling was conducted on the pre-dawn cast each day with a reduced set of samples from the midday cast. All samples and replicates were stored at -80 °C and were returned to SOC in liquid-N for analysis.
HPLC analysis was carried out according to Barlow et al. (1997).
References Cited
Barlow R.G., Cummings D.G. and Gibb S.W., 1997. Improved resolution of mono- and divinyl chlorophylls a and b and zeaxanthin and lutein in phytoplankton extracts using reverse phase C8 HPLC. Marine Ecology Progress Series, 161 , 303-307.
Instrumentation Description
Section not relevant.
BODC Data Processing Procedures
Data were submitted to BODC in Microsoft Excel spreadsheet format and saved to the archive with reference SOC040134. The file was provided to BODC with CTD cast number, date, and bottle depth as metadata.
Sample metadata were checked against information held in the database - there was one minor depth discrepancy. Data were provided from a sample collected from 160m during cast 21, but no bottle was fired at this depth instead bottles were fired at 150m and the data were loaded against this depth.
Parameter codes defined in BODC parameter dictionary were assigned to the variables as shown in the table below. Values were multiplied by one thousand where appropriate for conversion into nanograms per litre. Cells where a value was logged as 'Present' were changed to 0 and the flag '<' was added to show values were below the detection level of the instrument. Column headings were substituted for the appropriate BODC parameter code except for Tpigm and Tchla, which were derived from the summation of all pigment values and ChlA and Dv ChlA values repectively. These derived values were not loaded into the database.
Data loaded into BODC's database without any changes.
| Originator's Parameter | Units | Description | BODC Parameter Code | Units | Comments |
|---|---|---|---|---|---|
| Chl c3 | mg m -3 | Concentration of chlorophyll-c3 {chl-c3} per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | CLC3HPP1 | ng l -1 | Unit conversion x1000 applied |
| Chl c2 | mg m -3 | Concentration of chlorophyll-c2 {chl-c2} per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | CLC2HPP1 | ng l -1 | Unit conversion x1000 applied |
| Peridinin | mg m -3 | Concentration of peridinin per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | PERIHPP1 | ng l -1 | Unit conversion x1000 applied |
| 19'But | mg m -3 | Concentration of 19'-butanoyloxyfucoxanthin per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | BUTAHPP1 | ng l -1 | Unit conversion x1000 applied |
| Fucox | mg m -3 | Concentration of fucoxanthin per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | FUCXHPP1 | ng l -1 | Unit conversion x1000 applied |
| 19'Hex | mg m -3 | Concentration of 19'-hexanoyloxyfucoxanthin per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | HEXOHPP1 | ng l -1 | Unit conversion x1000 applied |
| Violax | mg m -3 | Concentration of violaxanthin per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | VILXHPP1 | ng l -1 | Unit conversion x1000 applied |
| Diadinox | mg m -3 | Concentration of diadinoxanthin per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | DIADHPP1 | ng l -1 | Unit conversion x1000 applied |
| Allox | mg m -3 | Concentration of alloxanthin per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | ALLOHPP1 | ng l -1 | Unit conversion x1000 applied |
| Zeax | mg m -3 | Concentration of zeaxanthin per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | ZEOXHPP1 | ng l -1 | Unit conversion x1000 applied |
| Dv ChlB | mg m -3 | Concentration of divinyl chlorophyll-b per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | DVCBHPP1 | ng l -1 | Unit conversion x1000 applied |
| Chl B | mg m -3 | Concentration of chlorophyll-b per unit volume of the water body [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | CHLBHPP1 | ng l -1 | Unit conversion x1000 applied |
| Dv ChlA | mg m -3 | Concentration of divinyl chlorophyll-a per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | DVCAHPP1 | ng l -1 | Unit conversion x1000 applied |
| ChlA | mg m -3 | Concentration of chlorophyll-a {chl-a} per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | CPHLHPP1 | mg m -3 | n/a |
| B-Carot | mg m -3 | Concentration of beta-carotene {beta,beta-carotene} per unit volume of the water column [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | BCARHPP1 | ng l -1 | Unit conversion x1000 applied |
Data Quality Report
The following values were reported as suspect by the originator and were flagged 'L' in the database: AMT13_30, 12m: Value for DV ChlA too low. AMT13_65, 52m: Value for DV ChlA too high.
Problem Report
This section is not relevant to this data set.
