Intellectual merit: Vitamins have long been recognized as compounds that play a central role in the metabolism and growth of marine phytoplankton but have not been investigated in the ocean for decades. This is, in part, because methods for directly measuring vitamins in the seawater did not exist. The large majority of dinoflagellates species surveyed (90%) require vitamin B12 for growth, but no study has directly examined the impact of vitamins on dinoflagellate bloom events. SUNY investigators have recently developed techniques for making the first direct measurements of vitamins in the ocean. These results indicate that levels are lower than previously estimated and may limit the growth of species that are auxotrophs for these vitamins. They have concurrently conducted fieldwork that demonstrates that vitamins can strongly influence the structure of marine phytoplankton communities and are capable of specifically stimulating the growth of large dinoflagellates.
The investigators will conduct a comprehensive investigation of how vitamins and other micronutrients and macronutrients impact the growth of dinoflagellates within three contrasting oceanographic regimes (an upwelling zone, an oligotrophic tropical coastal zone, and a temperate estuary) that are seasonally susceptible to large blooms of dinoflagellate species that have an absolute requirement for vitamin B12. Within each region, they will establish the dynamics of plankton community composition using standard techniques (pigments, flow cytometry and microscopy) and molecular quantification of bloom forming, vitamin B12-requiring, dinoflagellate species. They will concurrently establish vitamin (dissolved and particulate B12 and B1), nutrient, and bioactive trace metal concentrations, as well as vitamin and carbon uptake rates and the amino acid content of phytoplankton cells (an indicator of B12 limitation). They will conduct incubation experiments to assess the ability of vitamins, alone and in unison with nutrients and trace metals, to experimentally enhance dinoflagellate growth, biomass, vitamin uptake, and amino acid content. During recent decades, scientists have made great strides in understanding how N, P, Si, and Fe regulate primary production and phytoplankton community composition in the ocean. At the same time, no field study has directly examined the importance of organic micronutrients, particularly coenzymes like vitamin B12, on phytoplankton population dynamics. This shortcoming has prohibited a comprehensive understanding of the mechanisms controlling dinoflagellate blooms in the World's oceans.
Broader Impacts: The SUNY Investigators will partner with the Atlantis Marine World Aquarium in Riverhead, NY, which is located directly on one of our sampling sites, to directly disseminate the premise and results of our project to the public. They will provide seminars, flyers, and posters to staff members and the public at the aquarium. These activities have the potential to directly educate one million people regarding NSF-supported research over the life of this project. This study will represent an international collaboration between US and Mexican scientists and thus will involve students and scientists from both nations crossing borders to work on this project. This investigation will serve as the dissertation topic for doctoral students at Stony Brook University and will support a woman returning to work as a post-doctoral researcher. Both PIs have a strong record of supporting diversity in education and in enriching undergraduate and secondary school education and research. This project will annually involve multiple undergraduate students through Marine Sciences Research Center's (Stony Brook) NSF Research Experience for Undergraduates (REU) program. In addition, it is anticipated that the PIs will continue to annually host multiple undergraduate students from liberal arts colleges and high school students in their labs who will be engaged in this project. Finally, the PIs will continue to provide pro bono lectures and seminars at regional undergraduate only colleges and at underprivileged, minority-dominated high schools (i.e. New York City).
