Rising relative fluctuation as a warning indicator of discontinuous transitions in symbiotic metapopulations

Autor: Neeme Lumi, Romi Mankin, Katrin Laas
Rok vydání: 2015
Předmět:
Zdroj: Physica A: Statistical Mechanics and its Applications. 437:109-118
ISSN: 0378-4371
Popis: The long-time limit behavior of the stochastic Lotka–Volterra model of a symbiotic metapopulation subjected to generalized Verhulst self-regulation is considered. The influence of a time-variable environment on the carrying capacities of subpopulations is modeled as a periodic deterministic part and a symmetric dichotomous noise. Relying on the mean-field approach it is established that at certain parameter regimes the mean field (average subpopulations size) exhibits hysteresis in respect to the noise correlation time, manifested in the appearance of colored-noise-induced discontinuous transitions. Especially, it is shown that the relative fluctuation of the subpopulation sizes exhibits accelerated increase prior to abrupt transitions of the metapopulation state. Moreover, in certain cases the autocorrelation function of the population sizes demonstrates anticorrelation at some values of the lag time.
Databáze: OpenAIRE