The impact of stochasticity on the behaviour of nonlinear population models: synchrony and the Moran effect

J. V. Greenman, Timothy Guy Benton

    Research output: Contribution to journalArticle

    35 Citations (Scopus)

    Abstract

    Environmental variation is ubiquitous, but its effects on nonlinear population dynamics are poorly understood. Using simple (unstructured) nonlinear models we investigate the effects of correlated noise on the dynamics of two otherwise independent populations (the Moran effect), i.e, we focus on noise rather than dispersion or trophic interaction as the cause of population synchrony. We find that below the bifurcation threshold for periodic behaviour (1) synchrony between populations is strongly dependent on the shape of the noise distribution but largely insensitive to which model is studied, (2) there is, in general, a loss of synchrony as the noise is filtered by the model, (3) for specially structured noise distributions this loss can be effectively eliminated over a restricted range of distribution parameter values even though the model might be nonlinear, (4) for unstructured models there is no evidence of correlation enhancement, a mechanism suggested by Moran, but above the bifurcation threshold enhancement is possible for weak noise through phase-locking, (5) rapid desynchronisation occurs as the chaotic regime is approached. To carry out the investigation the stochastic models are (a) reformulated in terms of their joint asymptotic probability distributions and (b) simulated to analyse temporal patterns.

    Original languageEnglish
    Pages (from-to)343-351
    Number of pages8
    JournalOikos
    Volume93
    DOIs
    Publication statusPublished - 2001

    Keywords

    • SPATIAL SYNCHRONY
    • ENVIRONMENTAL CORRELATION
    • DYNAMICS
    • SCALE
    • DISPERSAL
    • OUTBREAKS
    • PATTERNS
    • ECOLOGY
    • SYSTEMS
    • NOISE

    Cite this

    The impact of stochasticity on the behaviour of nonlinear population models: synchrony and the Moran effect. / Greenman, J. V.; Benton, Timothy Guy.

    In: Oikos, Vol. 93, 2001, p. 343-351.

    Research output: Contribution to journalArticle

    Greenman, J. V. ; Benton, Timothy Guy. / The impact of stochasticity on the behaviour of nonlinear population models: synchrony and the Moran effect. In: Oikos. 2001 ; Vol. 93. pp. 343-351.
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    KW - PATTERNS

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    KW - SYSTEMS

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