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arXiv · 0807.0673

Population Uncertainty in Model Ecosystem: Analysis by Stochastic Differential Equation

Satoru Morita·Kei-ichi Tainaka·Hiroyasu Nagata·Jin Yoshimura
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Abstract

Perturbation experiments are carried out by contact process and its mean-field version. Here, the mortality rate is increased or decreased suddenly. It is known that the fluctuation enhancement (FE) occurs after the perturbation, where FE means a population uncertainty. In the present paper, we develop a new theory of stochastic differential equation. The agreement between the theory and the mean-field simulation is almost perfect. This theory enables us to find much stronger FE than reported previously. We discuss the population uncertainty in the recovering process of endangered species.

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Satoru Morita, Kei-ichi Tainaka, Hiroyasu Nagata, Jin Yoshimura. 2008-07-04. Population Uncertainty in Model Ecosystem: Analysis by Stochastic Differential Equation. https://doi.org/10.1143/jpsj.77.093801

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