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This dataset includes the concentrations of dissolved inorganic macronutrients (phosphate, nitrate plus nitrite (N+N), silicic acid, and nitrite), chlorophyll a and phaeophytin, and particulate organic nitrogen and carbon measured shipboard in samples collected from phytoplankton shipboard incubation experiments conducted on the FeOA cruise SKQ202209S on R/V Sikuliaq in the Northeast Pacific from June to July 2022. This project investigates the effects of ocean acidification on the associations between iron and organic ligands in seawater and on iron bioavailability to marine phytoplankton communities. The project used a combination of shipboard incubation experiments and depth profiles to characterize iron speciation and cycling across coastal upwelling, oligotrophic open ocean, and iron-limited subarctic oceanographic regimes in the NE Pacific. Surface seawater was incubated at pH of 8.1, 7.6, and 7.1 with natural iron and with dissolved iron amendments in order to investigate interactions between pH and iron bioavailability across the different regimes. Understanding how pH influences iron and its relationship with ligands provides important information for assessing the impacts of ocean acidification on primary production and biogeochemical processes.
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Dissolved Macronutrient Concentrations from Depth Profiles and Incubation Experiments from STING I Cruise AE2305 on R/V Atlantic Explorer in the Gulf of Mexico from February to March 2023
Concentrations of inorganic dissolved macronutrients, including phosphate, nitrate plus nitrite (N+N), silicic acid, and nitrite, from phytoplankton shipboard incubation experiments and depth profiles collected on STING I cruise AE2305 on R/V Atlantic Explorer in the Gulf of Mexico from February to March 2023. This project investigates how groundwater discharge delivers important nutrients to the coastal ecosystems of the West Florida Shelf. Preliminary studies indicate that groundwater may supply both dissolved organic nitrogen (DON) and iron in this region. In coastal ecosystems like the West Florida Shelf that have very low nitrate and ammonium concentrations, DON is the main form of nitrogen available to organisms. Nitrogen cycling is strongly affected by iron availability because iron is essential for both photosynthesis and for nitrogen fixation. This study will investigate the sources and composition of DON and iron, and their influence on the coastal ecosystem. The team will sample offshore groundwater wells, river and estuarine waters, and conduct two expeditions across the West Florida Shelf in winter and summer.
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- PAR ID:
- 10559200
- Publisher / Repository:
- Biological and Chemical Oceanography Data Management Office (BCO-DMO)
- Date Published:
- Subject(s) / Keyword(s):
- STING nutrient West Florida shelf
- Format(s):
- Medium: X
- Location:
- Gulf of Mexico, West Florida Shelf; (East Bound Longitude:-82.5; North Bound Latitude:28.5; South Bound Latitude:26.3; West Bound Longitude:-86.6)
- Right(s):
- Creative Commons Attribution 4.0 International
- Sponsoring Org:
- National Science Foundation
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