A turbulent diatom vs dinoflagellate phytoplankton biomass model

Phytoplankton blooms play an important role in global primary productivity and the dynamics of blooms are of interest to modellers. Diatom dominated phytoplankton blooms followed by dinoflagellate blooms are common in the Southern Benguela, and are often associated with Harmful Algal Blooms. A well-...

Full description

Bibliographic Details
Main Author: Kennedy, Kristen
Other Authors: Moloney, Coleen
Format: Others
Language:English
Published: University of Cape Town 2014
Online Access:http://hdl.handle.net/11427/7623
Description
Summary:Phytoplankton blooms play an important role in global primary productivity and the dynamics of blooms are of interest to modellers. Diatom dominated phytoplankton blooms followed by dinoflagellate blooms are common in the Southern Benguela, and are often associated with Harmful Algal Blooms. A well-known ecological explanation for the succession of diatoms to dinoflagellates is given by Margalef’s Mandala which attributes the successional change to the interaction between turbulence and available nutrient concentration. This study introduced a simple variable accounting for the effects of turbulence to a numerical model describing diatom and dinoflagellate growth in order to emulate the common successional pattern. Succession was successfully modelled by reducing the maximum growth rate of diatoms in stratified conditions. The model was then used to investigate the predictions of Margalef’s Mandala. This study unpicks the relationship between nutrients, turbulence, diatoms and dinoflagellates through a simple 0D phytoplankton model with interesting insight into the role of turbulence in phytoplankton dynamics.