Description:

Microplastics and the Estuarine Gauntlet

Transport of microplastics in estuaries depends on the interaction of particle buoyancy and three-dimensional circulation patterns. The physical and chemical properties of microplastic particles lead to a wide range of settling and rising velocities. This variability in buoyancy ultimately determines the likelihood of export to the coastal ocean and adjacent national marine sanctuaries versus deposition in Bay sediments and shorelines. We combine data from an extensive field campaign around San Francisco Bay and a numerical transport model to link particle loading from wastewater and stormwater to particle abundance in surface waters throughout the system. The results point to the heterogeneous and divergent fates of particles depending on buoyancy and density-driven circulation.

Rusty Holleman is a researcher at the University of California Davis Center for Watershed Sciences. He investigates the ties between hydrodynamics and ecology with numerical and field-based approaches. His past work ranges from the fundamentals of numerical diffusion and turbulent mixing to the implementation of low-cost sensing platforms. Before joining UC Davis he led the modeling group at the San Francisco Estuary Institute, developing hydrodynamic and nutrient cycling models of San Francisco Bay. In addition to research activities, he has built visualizations for science museums, and consulted on hydrodynamics for professional sailing teams.