AMT12 pigment composition by HPLC analysis from CTD bottle samples
Data Acquisition and Analysis
Fresh seawater samples from upto five light depths were collected from 60 casts 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. Despite regular contact with technical staff in the UK, persistent problems with the Thermofinigan HPLC system (comms problem with integrator, mysterious autosampler error message) resulted in no samples being analysed during the cruise. All samples and replicates were stored at -80 °C and were returned to SOC in liquid-N for analysis within 8 weeks.
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 SOC040045. The file was provided to BODC with cruise, station number, date, lat, lon, water depth and bottle depth as metadata.
Sample metadata were checked against information held in the database - there was one discrepancy. The file provided a sample from cast 48 at depth 8.1m, however there was no bottle sampled at this depth for this cast. There was a sample depth of 8.1m for cast 49 and it appears there was a typing error as the data falls after the deepest sample for cast 48 and the before the next shallowest sample for cast 49. This data has been entered against cast 49 depth 8.1m.
BODC were advised that the parameter 'Tchl b' refers to DivChlb + Chlb. Additional columns 'TChla', '%DvChla' and 'Zea/Hex' were not loaded as they are derived values and the parameter 'FlChl' was already provided to BODC and loaded to the database as the fluorometeric chlorophyll-a dataset.
Parameter codes defined in BODC parameter dictionary were assigned to the variables as shown in the table below. The data were provided in mg m -3 units that were converted to ng l -1 for all parameters but chlorophyll-a.
Data loaded into BODC's database without any changes.
| Originator's Parameter | Units | Description | BODC Parameter Code | Units | Comments |
|---|---|---|---|---|---|
| Chlc3 | 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 |
| Chlc2 | 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 |
| Perid | 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 |
| Fuco | 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 |
| Pras | mg m -3 | Concentration of prasinoxanthin per unit volume of the water body [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | PRSXHPP1 | ng l -1 | Unit conversion x1000 applied |
| Viol | 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 |
| Diadino | 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 |
| Allo | 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 |
| Zea | 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 |
| TChl b | mg m -3 | Concentration of chlorophyll-b+divinyl chlorophyll-b per unit volume of the water body [particulate >GF/F phase] by filtration, acetone extraction and high performance liquid chromatography (HPLC) | CBDVHPP1 | ng l -1 | Unit conversion x1000 applied |
| DvChla | 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 |
| BCar | 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 data originator indicated all data appear to be good.
Problem Report
This section is not relevant to this data set.
