Numerical study of plankton-fish dynamics in a spatially structured and noisy environment

Abstract

The effects of mobile fish schools and noisy zooplankton mortality on the plankton dynamics are described, using a minimal model of the nutrients-plankton-fish food chain. The space is divided into three habitats of different phytoplankton growth, a first with high productivity, connected to the second with productivity, linearly decreasing down to the level of the third habitat. The plankton growth, interactions and transport are modeled with reaction-diffusion equations whereas, the fish school motion is discrete and rule-based, depending on the local zooplankton density as well as on spatial position, previous direction and maximum residence time. (C) 2002 Elsevier Science B.V. All rights reserved.