Toxic phytoplankton-induced spatiotemporal patterns

Abstract

Here we consider a reaction diffusion system of three plankton populations, a zooplankton feeding on two phytoplankton populations, in two different settings. Firstly, the two phytoplanktons are both non-toxic and both enhance the growth of the grazing zooplankton. Secondly, we assume that one of the phytoplankton releases toxin and thereby inhibits the growth of the zooplankton. Our analytic and numerical study shows that the spatiotemporal distribution of the plankton species is uniform when both phytoplankton populations are non-toxic. However, in the presence of toxin-producing phytoplankton, the biomass distribution of all the plankton populations becomes inhomogeneous.Keywords Plankton dynamics · Toxin-producing phytoplankton · Toxin inhibition · Diffusion · Paradox of plankton · Diffusive instability Sanjay Chaudhuri has been supported by "MIUR Bando per borse a favore di giovani ricercatori indiani" during his visit at the University of Torino.

Travelling Waves in Plankton Dynamics

“…More precisely we consider the model studied in [2] where p 1 and p 2 are phytoplankton species and p 3 reprents zooplankton that feeds on the other two. In [2] two versions of the model are considered: the case where p 2 is toxic for the zooplankton is compared to the standard situation.…”

“…In [2] two versions of the model are considered: the case where p 2 is toxic for the zooplankton is compared to the standard situation.…”

“…In this case, also the functional form is different. In [2] the linear form has been chosen for the standard case, while the multiplier…”

“…In this paper we develop further the work undertaken in [2] on diffusive plankton movements, for which the action of the toxin-producing phytoplankton not only damages the grazers, but it can also cause spatial inhomogeneities. In [2] the steady states of this plankton model have been investigated and the corresponding spatiotemporal patterns discovered.…”

“…In [2] the steady states of this plankton model have been investigated and the corresponding spatiotemporal patterns discovered. Here, we study the possible insurgence of planktonic travelling waves, that ultimately produce these steady state distributions.…”