AMT16 Dissolved Organic Carbon (DOC) measurements from CTD bottle samples
Originator's Protocol for Data Acquisition and Analysis
Water samples were collected from 12 depths down to 300m during the pre-dawn CTD cast, including 6 main light depths. Samples were collected in previously acid-cleaned (10% HCl, v/v) HDPE bottles. The sub-samples were subsequently filtered through ashed (450 o C, 6 hours) GF/F filters (< 0.7 µm). The glass filtration unit was previously acid-cleaned and combusted to the same level as the filters. In addition it was acid-washed between CTD stations. Filtrates for DOC analysis were stored in clean glass ampoules, stabilised by acidification (pH 2, 50% (v/v) HCl), sealed with a gas torch and stored in a fridge (4 o C). Analytical procedures for DOC took place after the cruise.
The analysis was performed with a coupled high temperature catalytic (HTC) combustion system consisting of a Shimadzu 5000A total organic carbon (TOC) analyser with a platinum catalyst.
References Cited
Instrumentation Description
Not relevant to this data set.
BODC Data Processing Procedures
Data were submitted to BODC in a Microsoft Excel spreadsheet file (AMT16_DOC) and archive under BODC accession SOC080114. Sample metadata were checked against information held in the database - there were no discrepancies.
Parameter codes defined in BODC parameter dictionary were assigned to the DOC parameter. The data was provided in units which were consistent with those used for the relevant parameter in the BODC database. Data loaded into BODC's database using established BODC data banking procedures.
A parameter mapping table is provided below;
| Originator's Parameter | Units | Description | BODC Parameter Code | Units | Comments |
|---|---|---|---|---|---|
| DOC | µmol l -1 | Concentration of carbon (organic) {DOC} per unit volume of the water body [dissolved plus reactive particulate <GF/F phase] by filtration, acidification and high temperature Pt catalytic oxidation | CORGCOF1 | µmol l -1 | - |
Data Quality Report
BODC were not advised of specific quality checks carried out by the data originator. There were no standout values in the sample data provided to BODC.
Problem Report
Not relevant to this data set.
