Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Related Publications
• Related Datasets
• Parameters
• Instruments
• Project Information
• Program Information
• Funding

Study area: The main field study was conducted in a coral reef offshore from the Richard Gump South Pacific Research Station located next to Cook's Bay on the northern shore of Mo'orea, French Polynesia. Research was conducted by small boat in a shallow-water coral reef and offshore Pacific Ocean. See Figure 1 in Xue et al. (2022) for the geographic locations of French Polynesia, the island of Mo'orea, and the schematic description of the reef structure and the reef-ocean transect sampling locations. 

Water samples: A study was conducted to determine the rate constant and rate for the biological consumption of dissolved acrylate and DMSP. Experiments were performed using unfiltered water samples collected during diel sampling in the back reef and open Pacific Ocean stations.

Biological consumption of dissolved acrylate: To perform an incubation experiment for the biological consumption of acrylate, acrylate was added to unfiltered water samples in triplicate 250 milliliter (mL) polycarbonate (PC) bottles to yield an initial concentration of 10-15 nanomolar (nM). Another set of three PC bottles received no acrylate addition. Once samples were prepared, they were placed in a large incubator with hosing to continuously pump ambient seawater through the incubator to maintain the temperature at ~28 degrees Celsius.  Samples were incubated in the dark.  Subsamples (15 mL) were collected at four time points from each PC bottle during incubation, and the total length of each incubation was 14 hours for the back reef samples and 18 hours for the Pacific Ocean samples.

Biological consumption of dissolved DMSP: The biological consumption of DMSP was determined using the glycine betaine (GBT) inhibition method outlined in Kiene and Gerard (1995). Briefly, six PC bottles were filled with freshly collected, unfiltered seawater. Three bottles were treated with GBT to a final concentration of 10 micromolar (µM) and the other three bottles were left untreated. All samples were incubated in dark in the same incubator used for acrylate experiments. Subsamples (15 mL) were collected at several time points from each bottle for the measurement of DMSP concentrations.

Acrylate and organosulfur quantification: Acrylate concentrations were determined using a pre-column derivatization HPLC method (Xue and Kieber, 2021). For derivatization, 300 microliter (µL) thiosalicylic acid (20 mM) reagent was added into a 5 milliliter (mL) precleaned borosilicate vial containing 3 mL of a standard or seawater sample. The pH in each vial was adjusted to 4.0. Then each vial was tightly screw-capped and incubated at 90 degrees Celsius in a water bath for 6 hours. After cooling to room temperature, each derivatized sample was filtered using a 0.2 micrometer (µm) Nylon syringe filter followed by injection of a 1 mL sample into a Shimadzu reverse-phase HPLC with UV absorbance detection at 257 nanometers (nm). To measure concentrations of DMSP and DMSO, both compounds were first converted to DMS. To convert DMSP or DMSO to DMS, 200 µL 5 M NaOH or 20% TiCl3 was added to 1 mL of a standard or seawater sample in a precleaned borosilicate serum vial, which was immediately capped and sealed followed by incubation overnight for DMSP at room temperature or for DMSO at 55 degrees C for 1 hour. The produced DMS was analyzed using a cryogenic purge-and-trap system and a Shimadzu GC-14A with a flame photometric detector (Kinsey et al., 2016).

Notes: All samples from the biological consumption experiments were processed, stored, and analyzed for acrylate and DMSP using the same procedures used to measure DMSP and acrylate concentrations in the transect study (https://www.bco-dmo.org/dataset/879142).

Kbio_acrylate and Kbio_DMSP denote the first-order rate constants for biological consumption of acrylate and DMSP in the unit of per day (d-1).

Dissolved acrylate (Acrylate_d) and dissolved dimethylsulfoniopropionate (DMSP_d) concentrations were determined in the water samples used for the biological consumption experiments.

The concentrations of acrylate or DMSP at different time points were fit into a first-order decay kinetic model and the rate constants (+/- standard deviation) were determined by taking the slope of the best-fit line from linear regression analysis.

The biological consumption rate was calculated by multiplying the concentration of acrylate or DMSP with the rate constant in each sample.

This dataset used Microsoft excel, SigmaPlot version 11.0 for analyses.

BCO-DMO processing description:
- Adjusted field/parameter names to comply with BCO-DMO naming conventions
- Added a conventional header with dataset name, PI names, version date
- Combined date and time, and converted local time to ISO 8601 standard time (UTC)
- Added latitude and longitude  in decimal degrees for the sites (Back reef and Open Ocean)
 

NSF Award Abstract:

This project would investigate the marine chemistry of the compound acrylate. Acrylate is a mostly overlooked by-product of a very well-studied process through which a compound known as DMSP (dimethylsulfoniopropionate), a compound produced by phytoplankton, is converted to the gas dimethylsulfide (known as DMS). This process is an important part of understanding the marine cycling of sulfur, and DMS plays a role in cloud formation and climate. Thus, these aspects of the conversion of DMSP to DMS have received considerable attention. On the other hand, very little is known about acrylate concentrations, fluxes, or impacts in the oceans, even though it is produced during the conversion of DMSP to DMS. Acrylate concentrations and fluxes should at times be substantial, especially in shallow-water coral reefs or during blooms of DMSP-rich phytoplankton that are common throughout the world's oceans and often harmful or toxic. It is likely that acrylate is a reactive form of marine organic matter that significantly impacts the carbon cycle and ecology of the upper ocean. This project will foster research and educational opportunities for undergraduates and one graduate student through several avenues including field work with international collaborators, attendance at national and local meetings, mentoring, preparing for and delivering college-level lectures, and presentations made to the general public at forums such as Syracuse's Milton J. Rubenstein Museum of Science. Results will be disseminated through peer-reviewed publications, media communications, web-based data bases, and presentations at scientific meetings, public forums and in the classroom.

A three-year project is proposed to study the effect of sunlight on the formation and loss of acrylate in seawater, to model these processes in the water column, and to determine if photoproduction and photolysis are important pathways in the marine acrylate cycle in a shallow-water coral reef. Four objectives are planned to carry out this research: (1) synthesize radiocarbon-labeled DMSP as a source of radiocarbon-labeled acrylate for photolysis and uptake studies; (2) conduct laboratory experiments using a solar simulator to study the photolysis and photoproduction of acrylate in water and seawater under varying conditions (e.g., pH, temperature, oxygen concentration); (3) determine temperature and wavelength-dependent quantum yields for acrylate photolysis and acrylate photoproduction in seawater using a monochromatic irradiation system; and (4) conduct a field study at the Richard Gump Research Station to determine rates of photolysis, photoproduction and microbial consumption of acrylate in a shallow-water coral reef.

The Surface Ocean Lower Atmosphere Study (SOLAS) program is designed to enable researchers from different disciplines to interact and investigate the multitude of processes and interactions between the coupled ocean and atmosphere.

Oceanographers and atmospheric scientists are working together to improve understanding of the fate, transport, and feedbacks of climate relevant compounds, and also weather and hazards that are affected by processes at the surface ocean.

Oceanographers and atmospheric scientists are working together to improve understanding of the fate, transport, and feedbacks of climate relevant compounds.

Physical, chemical, and biological research near the ocean-atmosphere interface must be performed in synergy to extend our current knowledge to adequately understand and forecast changes on short and long time frames and over local and global spatial scales.

The findings obtained from SOLAS are used to improve knowledge at process scale that will lead to better quantification of fluxes of climate relevant compounds such as CO2, sulfur and nitrogen compounds, hydrocarbons and halocarbons, as well as dust, energy and momentum. This activity facilitates a fundamental understanding to assist the societal needs for climate change, environmental health, weather prediction, and national security.

The US SOLAS program is a component of the International SOLAS program where collaborations are forged with investigators around the world to examine SOLAS issues ubiquitous to the world's oceans and atmosphere.

» International SOLAS Web site

Science Implementation Strategy Reports

US-SOLAS (4 MB PDF file)
Other SOLAS reports are available for download from the US SOLAS Web site