Generation and cessation of oscillations: Interplay of excitability and dispersal in a class of ecosystem

TL;DR

This paper explores how species dispersal and excitability interact in ecological networks, revealing mechanisms for both the generation and cessation of oscillations, including amplitude and oscillation death, with implications for ecological stability.

Contribution

It demonstrates new dispersal-induced oscillation generation and cessation mechanisms in an ecological network modeled by the Truscott--Brindley system, highlighting multi-cluster states.

Findings

Dispersal induces oscillation generation in excitable ecological nodes.

Two mechanisms of oscillation cessation: amplitude and oscillation death.

Existence of multi-cluster states in ecological dispersal networks.

Abstract

We investigate the complex spatiotemporal dynamics of an ecological network with species dispersal mediated via a mean-field coupling. The local dynamics of the network are governed by the Truscott--Brindley model, which is an important ecological model showing excitability. Our results focus on the interplay of excitability and dispersal by always considering that the individual nodes are in their (excitable) steady states. In contrast to the previous studies, we not only observe the dispersal induced generation of oscillation but we also report two distinct mechanisms of cessation of oscillations, namely amplitude and oscillation death. We show that, the dispersal between the nodes influences the intrinsic dynamics of the system resulting multiple oscillatory dynamics such as period-1 and period-2 limit cycles. We also show the existence of multi-cluster states which has much relevance and importance in ecology.