Phytoplankton account for half of global primary productivity and their biomass and community composition significantly impact global carbon and other biogeochemical cycles and ecosystem functioning. Explaining patterns of global distributions of phytoplankton groups and predicting how phytoplankton communities will re-organize under anthropogenic environmental change requires knowledge of diverse eco-physiological traits defining ecological niches of phytoplankton species. In this project, the investigators will assemble a query-based database of diverse phytoplankton traits such as cell/colony size, growth rates, resource acquisition and predator avoidance traits, among others. Data for all available species and strains will be included. They will use the database to answer fundamental questions in phytoplankton ecology such as: 1) what traits exhibit trade-offs (pairwise and beyond) and what shapes are they? 2) What traits scale allometrically with cell/body size? Can scaling exponents from first principles be predicted? What are potential limits to allometric scaling as a way of simplifying the complex trait space that characterizes real organisms? 3) What are trait differences among major functional/taxonomic groups of phytoplankton and how much does taxonomy/phylogeny constrain particular functional traits? 4) Are there differences in trait distributions between marine and freshwater groups?
The investigators will also use the database to parameterize novel models of phytoplankton community organization and evolution based on adaptive dynamics approaches. They will use the models to explore how community structure emerges under different environmental scenarios, given physiological constraints and ecological interactions. Changes in elemental stoichiometry, size structure and functional group distributions at different spatial and temporal scales will also be examined.
The broader impacts of the project will benefit the scientific community as well as provide broad educational experiences. The investigators will produce a database of a diverse set of phytoplankton traits that will be made available to the wide scientific community. The database will be used to parameterize models of phytoplankton functional groups and explore mechanisms of community organization under different environmental conditions, including global change scenarios. By applying general ecological principles and novel ecoinformatics and modeling tools to answer fundamental questions about phytoplankton communities and biological oceanography, this project will span the interdisciplinary boundaries and should, therefore, advance our understanding of aquatic ecosystem functioning. The project includes training opportunties for a graduate student and a postdoc. In addition, teachers from local schools will be invited to work with the investigators in the summer to develop inquiry-based educational modules on phytoplankton ecology and global change that will include findings from this project. The results of this project will be disseminated through publications in a wide range of journals covering ecological, oceanographic and biogeochemical fields.