Metadata Report for BODC Series Reference Number 2273066

• Metadata Summary

• Problem Reports

• Data Access Policy

• Narrative Documents

• Project Information

• Data Activity or Cruise Information

• Fixed Station Information

• BODC Quality Flags

• SeaDataNet Quality Flags

Metadata Summary

Problem Reports

No Problem Report Found in the Database

Data Access Policy

Open Data

These data have no specific confidentiality restrictions for users. However, users must acknowledge data sources as it is not ethical to publish data without proper attribution. Any publication or other output resulting from usage of the data should include an acknowledgment.

If the Information Provider does not provide a specific attribution statement, or if you are using Information from several Information Providers and multiple attributions are not practical in your product or application, you may consider using the following:

"Contains public sector information licensed under the Open Government Licence v1.0."

Narrative Documents

Niskin Bottle

The Niskin bottle is a device used by oceanographers to collect subsurface seawater samples. It is a plastic bottle with caps and rubber seals at each end and is deployed with the caps held open, allowing free-flushing of the bottle as it moves through the water column.

Standard Niskin

The standard version of the bottle includes a plastic-coated metal spring or elastic cord running through the interior of the bottle that joins the two caps, and the caps are held open against the spring by plastic lanyards. When the bottle reaches the desired depth the lanyards are released by a pressure-actuated switch, command signal or messenger weight and the caps are forced shut and sealed, trapping the seawater sample.

Lever Action Niskin

The Lever Action Niskin Bottle differs from the standard version, in that the caps are held open during deployment by externally mounted stainless steel springs rather than an internal spring or cord. Lever Action Niskins are recommended for applications where a completely clear sample chamber is critical or for use in deep cold water.

Clean Sampling

A modified version of the standard Niskin bottle has been developed for clean sampling. This is teflon-coated and uses a latex cord to close the caps rather than a metal spring. The clean version of the Levered Action Niskin bottle is also teflon-coated and uses epoxy covered springs in place of the stainless steel springs. These bottles are specifically designed to minimise metal contamination when sampling trace metals.

Deployment

Bottles may be deployed singly clamped to a wire or in groups of up to 48 on a rosette. Standard bottles and Lever Action bottles have a capacity between 1.7 and 30 L. Reversing thermometers may be attached to a spring-loaded disk that rotates through 180° on bottle closure.

Nitrogen nutrient uptake and particulate organic nitrogen data series for cruise Charles Darwin CD132

Content of Data Series

Originator's Protocol for Data Acquisition and Analysis

The following methodology was compiled from information extracted from the CD132 cruise report (Burkill 2002) and from information provided by the originators.

NO3 and NH4 uptakes were determined at 8 depths throughout the euphotic zone (defined as the depth of the 0.1% irradiance level) to allow determination of integrated rates of nitrogen uptake. Water was collected pre-dawn into 2 x triplicate 0.6 litre polycarbonate bottles and inoculated with 15N-NO3 and 15N-NH4 to 10% of the ambient concentration to a minimum of 5 nmol l-1. Bottles were attached to a free floating incubation rig at the depth from which they were collected for approximately 5 hours, after which they were size-fractionated by filtration into the total and <2.0µm communities before drying and storing. Filters were dried onboard and stored over silica gel prior to analysis in the laboratory using continuous flow isotope-ratio mass spectrometry (IRMS). Only the GF/F filters used to collect particles from the total planktonic community were analysed for this dataset (pers. comm.). Size-fractionated data from the less than 2µm fraction are not therefore available.

References Cited

Burkill PH (2002). RRS Charles Darwin cruise 132. Analysing the Microbial Biodiversity of the Indian Ocean - AMBITION. 30 Aug-29 Sep 2001. Marine and Freshwater Microbial Biodiversity Cruise Report No.1, 56pp.

BODC Data Processing Procedures

Data were submitted to BODC in an Excel spreadsheet containing station identifiers, nominal sample depth, amount of 15N added as nitrate and as ammonium, particulate nitrogen, ambient nitrate and ammonium, nitrate and ammonium uptake rates per unit volume and per unit area, f'-ratio and C:N uptake ratio.

Parameter codes were assigned to the variables selected for inclusion in the database. These were uptake rates of nitrate and ammonium per unit volume and per unit area, and particulate nitrogen concentrations. Single-depth uptake data were loaded, unaltered, into the data-holding table for discrete depth measurements from incubated samples, INCDATA. Uptake rates integrated over the depth profile were loaded in the data-holding table for integrated measurements based on incubation experiments, INTINC. Particulate organic nitrogen concentrations data were loaded in BODC's main data table for discrete depth measurements, BOTDATA. The associated metadata was loaded into INCSAMP, INCINDX and BOTTLE.

Data Quality Report

None Reported

Problem Report

None Reported

Project Information

No Project Information held for the Series

Data Activity or Cruise Information

Data Activity

BODC Sample Metadata Report for CD132_CTD_CD132_021

Please note:the supplied parameters may not have been sampled from all the bottle firings described in the table above. Cross-match the Sample Reference Number above against the SAMPRFNM value in the data file to identify the relevant metadata.

Related Data Activity activities are detailed in Appendix 1

Cruise

Complete Cruise Metadata Report is available here

Fixed Station Information

No Fixed Station Information held for the Series

BODC Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

SeaDataNet Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

Appendix 1: CD132_CTD_CD132_021

Related series for this Data Activity are presented in the table below. Further information can be found by following the appropriate links.

If you are interested in these series, please be aware we offer a multiple file download service. Should your credentials be insufficient for automatic download, the service also offers a referral to our Enquiries Officer who may be able to negotiate access.