Criteria for linearized stability for a size-structured population model

Abstract

We consider a size-structured aggregation and growth model of phytoplankton community proposed by Ackleh and Fitzpatrick [2]. The model accounts for basic biological phenomena in phytoplankton community such as growth, gravitational sedimentation, predation by zooplankton, fecundity, and aggregation. Our primary goal in this paper is to investigate the long-term behavior of the proposed aggregation and growth model. Particularly, using the well-known principle of linearized stability and semigroup compactness arguments, we provide sufficient conditions for local exponential asymptotic stability of zero solution as well as sufficient conditions for instability. We express these conditions in the form of an easy to compute characteristic function, which depends on the functional relationship between growth, sedimentation and fecundity. Our results can be used to predict long-term phytoplankton dynamic