California Current Ecosystem LTER

Total Dissolved Organic Carbon and Nitrogen (Process Cruise)

Title
Total dissolved organic carbon and nitrogen measurements at selected depths in the water column from CCE LTER process cruises in the California Current System, 2006 - 2021 (ongoing).

Abstract
Water column bottle samples at multiple depths are taken during CCE Process cruises (since 2006, ongoing) at various CTD stations, and measurements of total organic carbon (TOC) and total nitrogen (TN) are performed onshore in the lab. TOC includes both dissolved and particulate organic carbon (DOC and POC, respectively). TN includes particulate and dissolved organic nitrogen as well as dissolved inorganic nitrogen species. In open ocean waters, POC is subtracted from TOC, and likely provides an accurate estimate of DOC because particles are typically small and homogeneously distributed in the sample. In coastal waters, and at stations where relatively high chlorophyll concentrations are present, the TOC measurement is not easily converted to DOC by subtracting POC values. Experience has shown that particles in these regions are large and inhomogeneously distributed. Therefore, samples collected in the CCE are reported as TOC and TN, expressed as micromoles of carbon (nitrogen) per liter of sea water.

Keywords
marine, measurements, carbon, organic matter, Organic Matter, RAPID: Responses of the California Current Ecosystem to El Nino 2015-16, nitrogen

LTER Data System Record
http://dx.doi.org/10.6073/pasta/d89d2c3c0cde7dce11bd0beba5f7a25f
Projects
California Current Ecosystem LTER

Creators
Aluwihare, Lihini (laluwihare@ucsd.edu)

Contact
CCE LTER Information Manager (ccelter.im@gmail.com)

Other Personnel
Stephens, Brandon

Data

table TotalDissolvedOrganicCarbonandNitrogen
Main data table for dataset
Rows: 1682
Columns: 11
View / Download

Methods


General Methods
Seawater samples (40 mL) will be drawn from the CTD rosette into combusted glass vials with acid-washed Teflon caps, acidified with 2 drops of 12N HCl and stored at room temperature (Aluwihare et al. 2002). Samples from Time-Series cruises will be processed in the shore-based laboratory with a Shimadzu TOC-V analyzer with a DON upgrade. This instrument will be fitted for shipboard analyses on the Process cruises, allowing real-time measurements of DOC and DON to follow DOM dynamics of natural blooms or shipboard incubations (Boyle et al. 1994).

Frequency
Selected Stations Seasonally

Protocols


Dissolved Organic Carbon and Total Nitrogen Methods and Protocls
http://cce.lternet.edu/data/methods-manual/augmented-cruises/dissolved-organic-carbon-and-total-nitrogen