930259 CHISHOLM Planktonic size spectra (the distribution of total biomass among different size classes) are a manifestation of the structure and function of pelagic ecosystems. As such, they embody information which could be useful for understanding the regulation of productivity in different biogeochemical provinces of the oceans. They also contain information essential to formulating algorithms to interpret satellite ocean color measurements. The overall goal of this project is to study, through observation and experimentation, how the characteristics of planktonic size spectra vary in different regions of the oceans and to determine what the underlying mechanisms are that generate and maintain them. Flow cytometry will be used to develop automated techniques for the generation of pelagic size spectra in the 0.3 to 100 micrometer size range, allowing one to measure size and abundance of picoplankton, phytoplantkon, bacteria, and microzooplankton. Once developed these methods will be applied to studies in a variety of different oceanographic regimes under a variety of different conditions. ***
