Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
  • BCO-DMO Processing Description
• Data Files
• Related Publications
• Related Datasets
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

This dataset contains the dissolved organic sulfur (DOS), dissolved organic phosphorus (DOP), dissolved organic bromine (DOBr) and dissolved organic iodine (DOI) data from solid-phase extracted (Agilent Bond Elut PPL) samples following the methods described in Gonsior et al. (2024) (doi:10.1039/D3VA00361B) for DOS and DOP and in Powers et al. (2024) (doi: 10.1016/j.scitotenv.2023.169292) for dissolved organic bromine (DOBr) and dissolved organic iodine (DOI).  

Water samples were collected using the ship's CTD profiler and 12 L Niskin bottles. 10 L water samples from each depth were then transferred into 5 gallon polycarbonate water bottles, passed through combusted 0.7 micron glass fiber filters and extracted.

The solid-phase extracted methanolic sample was dried under nitrogen and re-dissolved in pure water prior to DOS, DOP, DOBr, and DOI analysis by ICP-MS. Samples for DOBr and DOI analysis were also passed through silver cartridges prior to analysis to remove residual halides. DOS and DOP were analyzed by ICP-MS/MS using oxygen as the reaction gas and DOBr and DOI were analyzed by ICP-MS/MS with no gas in the Octopole Reaction System.

All data are scaled for extraction volume and dilution. No further processing was performed.

* Table within submitted file "BATS_Aloha_dates_DOS_DOP_DOBr_DOI.csv" was imported into the BCO-DMO data system for this dataset. Values "NaN" imported as missing data values.   Table will appear as Data File: 986596_v1_dissolved-organic-profiles.csv (along with other download format options).

Missing Data Identifiers:
* In the BCO-DMO data system missing data identifiers are displayed according to the format of data you access. For example, in csv files it will be blank (null) values. In Matlab .mat files it will be NaN values. When viewing data online at BCO-DMO, the missing value will be shown as blank (null) values.

* Column names adjusted to conform to BCO-DMO naming conventions designed to support broad re-use by a variety of research tools and scripting languages. [Only numbers, letters, and underscores.  Can not start with a number]

* Date converted to ISO 8601 format

NSF Award Abstract:
This study focuses on the sources and composition of colored dissolved organic matter (CDOM) in the ocean. CDOM is a part of water that absorbs sunlight. This material is important because it filters out harmful ultraviolet radiation. Scientists use it to track the movement of carbon and other important biological and chemical processes in the ocean. Organisms such as algae living in the open ocean have been shown to be sources of CDOM, but the chemical composition of these algal natural products remains to be discovered. Recent results from studying common algae show that viruses may break down algal cells and release material that looks like CDOM. This study will use new tools to find out if viruses and algae are creating this material and study its chemical makeup. This project will support two graduate students and provide summer internships for undergraduates through the NSF Research Experiences for Undergraduates (REU) program. The investigators will participate in a range of education and outreach activities.

The sources and structural nature of marine CDOM within the oceans remain unclear and continue to be a subject of debate. Marine in situ sources of CDOM have been suggested and some have been confirmed, but thus far none could explain the ubiquitous appearance of the so called "humic-like" CDOM component. Unique features of this component include its unusual exponential behavior in ultraviolet-visible (UV-Vis) absorbance with the absorbance extending well above 400 nm, and the large Stoke's shift in fluorescence spectroscopy. Picocyanobacteria are ubiquitous in the World's Oceans and make up 50 % of the autotrophic marine primary production. Preliminary results showed that the picocyanobacteria Synechococcus and Prochlorococcus release CDOM that matched the "humic-like" appearance of globally observed marine CDOM after virus-induced lysis. The main focus of this study is the characterization of the optical properties and molecular composition of viral-lysed DOM (VDOM) from different strains of Synechococcus and Prochlorococcus and additionally Trichodesmium which was shown in a previous study to also release CDOM. Associations between the chemical characterization information and metagenomics and transcriptomics data will be investigated for picocyanobacteria in the Pacific and Atlantic Oceans. This study includes long-term incubation experiments to determine the persistence of picocyanobacteria-derived CDOM as well as changes in microbial communities and processes (gene expression) that are related to the degradation of VDOM during the incubation period.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.