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arXiv · 1304.6226

Species abundances and lifetimes: from neutral to niche-stabilized communities

Simone Pigolotti·Massimo Cencini
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Abstract

We study a stochastic community model able to interpolate from a neutral regime to a niche partitioned regime upon varying a single parameter tuning the intensity of niche stabilization, namely the difference between intraspecific and interspecific competition. By means of a self-consistent approach, we obtain an analytical expression for the species abundance distribution, in excellent agreement with stochastic simulations of the model. In the neutral limit, the Fisher log-series is recovered, while upon increasing the stabilization strength the species abundance distribution develops a maximum for species at intermediate abundances, corresponding to the emergence of a carrying capacity. Numerical studies of species extinction-time distribution show that niche-stabilization strongly affects also the dynamical properties of the system by increasing the average species lifetimes, while suppressing their fluctuations. The results are discussed in view of the niche-neutral debate and of their potential relevance to field data.

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Simone Pigolotti, Massimo Cencini. 2013-09-16. Species abundances and lifetimes: from neutral to niche-stabilized communities. https://doi.org/10.1016/j.jtbi.2013.08.024

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