SS3.02 Turbulence and Plankton Dynamics
Date: Wednesday, June 12, 2002
Time: 3:00:00 PM
Location: Saanich
 
HuismanJ, Aquatic Microbiology, University of Amsterdam, Amsterdam, Netherlands, jef.huisman@science.uva.nl
Sommeijer, B, P, National Center for Mathematics and Computational Science, Amsterdam, Netherlands, B.P.Sommeijer@cwi.nl
 
COMPETITION BETWEEN SINKING AND BUOYANT PHYTOPLANKTON SPECIES IN RELATION TO MIXING PROCESSES
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Though most plankton competition studies have focussed on well-mixed systems, many natural plankton communities are not well mixed. In particular, pronounced phytoplankton depth profiles may develop if local growth rates and/or transport rates of phytoplankton overcome the homogenizing effects of turbulent diffusion. Would slow mixing of the water column lead to different outcomes of competition than expected on the basis of well-mixed laboratory experiments? Here, we use a reaction-advection-diffusion model to investigate the effects of vertical eddy diffusivity on competition for light between sinking and buoyant phytoplankton species. In particular, we focus on the question which mixing regimes will select for species with high sinking rates, which mixing regimes will favor neutrally buoyant species, and which regimes will favor positively buoyant species.