| Contributors | Affiliation | Role |
|---|---|---|
| Ohman, Mark D. | University of California-San Diego Scripps (UCSD-SIO) | Principal Investigator |
| Leblanc, Karine | Aix-Marseille University (AMU) | Co-Principal Investigator |
| Rauch, Shannon | Woods Hole Oceanographic Institution (WHOI BCO-DMO) | BCO-DMO Data Manager |
During BioSWOT-Med, vertical phytonet hauls were performed from the R/V L’Atalante at three locations near water parcels sampled by Zooglider, two south of Menorca (Stas. M, M2) and one in the eddy (Sta. B3, Fig. 1a, Suppl. Table S1). Each haul was from 0-150 meters (m) with a 20-micrometer (µm) mesh net. Net collector contents were diluted to 1 liter (L) with filtered seawater. Two samples (60 milliliters (mL)) were fixed with acidified Lugols solution and buffered formaldehyde for light microscopy observations. One mL of the fresh net material was filtered onboard without fixative at low vacuum onto a 25-millimeter (mm) polycarbonate membrane and rinsed with MilliQ water, dried for 3 hours at 50 degrees Celsius (°C), then kept at room temperature for subsequent SEM analyses. Phytoplankton diversity was assessed by cell counts in light microscopy (Nikon TE200) while SEM samples were gold coated and analyzed on a Phenom ProX benchtop SEM. From the samples, diatom identification and measurements were made of the longest chains visible for each genus or species that was relatively abundant.
Data were tabulated in a spreadsheet.
- Loaded sheet 3 from Excel file "BCO-DMO-DATASET_Lab_maximum_chain_lengths.xlsx" into the BCO-DMO system.
- Renamed columns to comply with BCO-DMO naming conventions.
- Saved the final file as "1001364_v1_maximum_chain_lengths.csv".
| Parameter | Description | Units |
| Station | Oceanographic station where phytonet sample was taken | unitless |
| ISO_DateTime_UTC | Start date/time for phytonet sample (UTC) | unitless |
| Latitude | North latitude | degrees |
| Longitude | East longitude | degrees |
| Taxon | Phytoplankton chain taxonomic category | unitless |
| Maximum_length_mm | Maximum length of chains of this taxonomic designation measured in the laboratory from this station. | millimeters (mm) |
| Comments | Explanation when maximum chain length estimated rather than measured. In some cases, where only individual cells or very short chains were found, an assumption of a maximum of 20 cells per chain was made for maximal length estimates, based on individual cell dimensions. | unitless |
| Corresponding_Zoocam_Category | Assignment of each phytoplankton type measured in the laboratory to 1 of 5 phytoplankton categories recognized from in situ imaging by Zoocam on Zooglider | unitless |
| Dataset-specific Instrument Name | Nikon TE200 |
| Generic Instrument Name | Microscope - Optical |
| Dataset-specific Description | Phytoplankton diversity was assessed by cell counts in light microscopy (Nikon TE200). |
| Generic Instrument Description | Instruments that generate enlarged images of samples using the phenomena of reflection and absorption of visible light. Includes conventional and inverted instruments. Also called a "light microscope". |
| Dataset-specific Instrument Name | Phytoplankton Net |
| Generic Instrument Name | Phytoplankton Net |
| Dataset-specific Description | Phytonet of diameter 0.57 m, mesh 20 um, retrieved vertically from 150-0 m. |
| Generic Instrument Description | A Phytoplankton Net is a generic term for a sampling net having mesh size of 150 microns or less that is used to collect phytoplankton. It is used only when detailed instrument documentation is not available. |
| Dataset-specific Instrument Name | Phenom ProX benchtop SEM |
| Generic Instrument Name | Scanning Electron Microscope |
| Dataset-specific Description | SEM samples were gold coated and analyzed on a Phenom ProX benchtop SEM |
| Generic Instrument Description | A scanning electron microscope (SEM) scans a focused electron beam over a surface to create an image. The electrons in the beam interact with the sample, producing various signals that can be used to obtain information about the surface topography and composition. |
| Dataset-specific Instrument Name | Zooglider |
| Generic Instrument Name | Zooglider |
| Dataset-specific Description | Measurements in this dataset were compared with measurements of comparable chain types imaged in situ by the Zoocam on Zooglider. |
| Generic Instrument Description | Zooglider, designed and built at the Scripps Institution of Oceanography, as described in Ohman et al. (2019. Limnology and Oceanography-Methods 17: 69-86 doi 10.1002/lom3.10301). It is based on a Spray glider hull (Sherman et al. 2002. IEEE Journal of Oceanic Engineering 26: 437-446 doi 10.1109/48.972076), modified with custom optical and acoustic sampling instruments.
|
| Website | |
| Platform | R/V L'Atalante |
| Start Date | 2023-04-21 |
| End Date | 2023-05-15 |
| Description | French-led BIOSWOT-Med study in the Northwestern Mediterranean Sea in Spring 2023. This study was one of the Adopt-a-Crossover field studies carried out around the world in synchrony with the launch by NASA/CNES of the new SWOT satellite for enhanced ocean altimetry. |
NSF Award Abstract:
Ocean fronts are regions of sharp horizontal discontinuities that can alter phytoplankton growth rates and community composition, zooplankton distributions and grazing activity, and predator foraging success. This study is using Zooglider, an autonomous ocean sampler equipped with a range of sensors and capitalizing on a unique opportunity to investigate frontal gradients and plankton communities in the western Mediterranean Sea. It is timed to coincide with a rapid crossover phase of a new NASA satellite mission. The combination of satellite and field-collected data will provide high resolution of the bio-physical consequences of oceanic frontal processes. The project incorporates training for graduate and undergraduate students as well as public outreach. Results are broadly communicated by partnering with a major public aquarium that serves 450,000 visitors per year, including by exhibiting novel porcelain ‘Zooware’ meant to convey the sensory experience of exploring the ocean’s planktonic fauna.
This project focuses on advancing understanding of frontal processes in the western Mediterranean Sea, at a ‘crossover’ site where NASA’s new Surface Water Ocean Topography (SWOT) satellite is making high-frequency sea surface height measurements using a high-resolution sensor. Measurements from the SWOT satellite are resolving small changes in sea-surface height, making it possible to follow the development and temporal progression of ocean frontal systems. The investigator is assessing the consequences of these frontal systems by testing the hypotheses that 1) zooplankton, marine snow particles, and predators are altered in these ocean frontal regions with a size-dependent or trait-dependent response; 2) particle-grazing zooplankton are more closely associated with layers of marine snow than with layers of living phytoplankton; 3) vertical thin layers of zooplankton are more likely to form in frontal than non-frontal regions; and 4) higher predators such as zooplanktivorous fish and marine mammals are more detectable in frontal regions The project makes use of an autonomous ocean instrument, the Zooglider. It includes a shadowgraph imaging Zoocam for resolving zooplankton and marine snow; a dual frequency Zonar to resolve mesozooplankton and larger sources of acoustic backscatter; and a sensitive hydrophone for recording ambient sounds, especially from marine mammals and fishes. These autonomous measurements are coordinated with complementary measurements from a ship-based sampling program, other autonomous vehicles, and satellite remote sensing.
| Funding Source | Award |
|---|---|
| NSF Division of Ocean Sciences (NSF OCE) | |
| French National Research Agency (ANR) |