The Influence of Reduced Light on Competing Zooplanktonic Populations – Inference from Mathematical Modeling and Field Data

Abstract

A diffusion model for the competition of three zooplankton populations is developed, that is based on earlier ideas on reduced phytoplankton abundance at large depths in the ocean, due to light absorption in the higher water layers and shading by other upper residing microorganisms. Equilibria of the diffusion-free system are analysed. A sensitivity analysis in terms of some population interaction parameters that are difficult to assess is performed. Simulations of the space-dependent system reveal the changes in the populations abundances in the various water layers, showing their expected reduction with increasing depths.