No abstract

Cyanobacteria, also known as blue-green algae, often cause harmful algal blooms and release toxic substances that can harm humans and other animals. Accurately modeling these phytoplankton is a step towards predicting, preventing, and controlling such blooms. Cyanobacteria and zooplankton species are known to migrate vertically in the water column on a daily cycle. Capturing this behavior is one aspect of correctly modeling their dynamics. Here, several models of cyanobacteria vertical movement were tested in proof-of-concept models before being applied to data from field studies. These models included both continuum and particle-tracking frameworks. Four continuum-framework models of cyanobacteria vertical migration were chosen to add to the numerical hydrodynamic, waterquality model CE-QUAL-W2. These were tested using a model of Dexter Reservoir (Oregon), where they predicted vertical migratory movement seen in cyanobacteria.Models of zooplankton migration were also tested in proof-of-concept models as a steppingstone towards future incorporation into CE-QUAL-W2. Preliminary models of cyanobacteria and zooplankton vertical migration using a particle-tracking framework also provided information to be used in future model developments that will incorporate vertical migration of plankton into the particle-tracking module of CE-QUAL-W2.ii