Time scales, persistence and patchiness.

H M Hastings; R Pekelney; R Monticciolo; D vun Kannon; D del Monte

doi:10.1016/0303-2647(82)90043-0

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PubMed · 7165795

Time scales, persistence and patchiness.

H M Hastings·R Pekelney·R Monticciolo·D vun Kannon·D del Monte

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Abstract

We consider competition in patch-dynamical and more general diffusion-extinction models. These models identify three time scales in ecology. We begin with a reformulation of Levin's 1978 basic model, using a geometric description of diffusion. As in Levin's model, diffusion drives short-term dynamics, and longer-term dynamics depends upon a diffusion-extinction ratio; maximizing this ratio is shown to be an Evolutionarily Stable Strategy. Over still longer times, the effect of organisms upon their environments becomes paramount. We use Mandelbrot's 1977 fractals to develop these models, and thus relate persistence with relative patchiness. Finally, we propose a numerical measure, the fractal exponent H, of successional stage.

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Biological Evolution Ecology Mathematics Models, Biological Plants Time Factors Comparative Study Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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H M Hastings, R Pekelney, R Monticciolo, D vun Kannon, D del Monte. 1982. Time scales, persistence and patchiness.. https://doi.org/10.1016/0303-2647(82)90043-0

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