Coastal Phytoplankton Dynamics Revealed by Automated Submersible Flow Cytometry

Many aspects of how natural plankton communities are regulated remain poorly understood, in  large part because traditional organism-level sampling strategies are not amenable to high  frequency, long duration application. To overcome aspects of this limitation, we developed the  FlowCytobot series of automated submersible flow cytometers capable of rapid, unattended  analysis of individual phytoplankton cells for long periods of time. FlowCytobot and Imaging  FlowCytobot use a combination of laser-based scattering and fluorescence measurements and  video imaging of individual particles to enumerate and characterize cells ranging from  picocyanobacteria to large chaining-forming diatoms. When combined with automated image  processing and classification, these observations make it possible to characterize taxonomic  composition of plankton communities with unprecedented temporal resolution, ranging from  hours to years. In this talk I will highlight ways multi-year time series from deployments at  coastal observatories are providing new insights into seasonal and interannual bloom dynamics  on the New England shelf (Martha's Vineyard Coastal Observatory) and contributing both early  warning and ecological context for Harmful Algal Bloom events in Texas waters. High resolution  observations at the level of individual cells make it possible, not only to characterize community  structure, but also to evaluate bottom up mechanisms through quantification of taxon-specific  growth rates. 

Speaker: Heidi Sosik