Date of Award

Spring 2017

Project Type


Program or Major


Degree Name

Master of Science

First Advisor

Kai Ziervogel

Second Advisor

Tim Moore

Third Advisor

Adrian Marchetti


Our current understanding of how turbulence affects small planktonic organisms is based on fluid dynamic theory, ocean models, and laboratory experiments that often have conflicting results. Atmospheric models predict that global temperature rise associated with climate change will affect turbulence patterns within the marine photic zone, where phytoplankton reside. To investigate how small-scale turbulence affects growth (growth rates, cell counts and extracted chlorophyll, and nutrient quotas) and metabolism (production of transparent exopolymer particles (TEP)) of marine primary producers, phytoplankton in monoculture and natural assemblages were incubated under a range of turbulent treatments. Results indicate that early in exponential growth of the monocultures, cell-specific TEP was higher with increased turbulence. During mid- and late exponential growth, there were no measurable differences in phytoplankton growth and TEP production as a function of turbulence. However, nutrient quotas were higher in the more turbulent tanks with phytoplankton cells >15 µm in length. Data from this study suggest that changes in turbulence in marine photic zones could result in increased nutrient storage in larger phytoplankton cells, as predicted by numerical models, but may not greatly affect the global carbon cycle via changes in TEP production.