Diversity patterns from ecological models at dynamical equilibrium

Authored by M Lassig, U Bastolla, SC Manrubia, A Valleriani

Date Published: 2001

DOI: 10.1006/jtbi.2001.2324

Sponsors: No sponsors listed

Platforms: No platforms listed

Model Documentation: Other Narrative Mathematical description

Model Code URLs: Model code not found

Abstract

We study a dynamic model of ecosystems where an immigration flux assembles the species community and maintains its biodiversity. This framework is particularly relevant for insular ecosystems. Population dynamics is represented either as an individual-based model or as a set of deterministic equations for population abundances. Local extinctions and immigrations balance at a statistically stationary state where biodiversity fluctuates around a constant mean value. We find a number of scaling laws characterizing this stationary state. In particular, the number of species increases as a power law of the immigration rate. With additional assumptions on the immigration flux, we obtain species-area relationships in agreement with observations for archipelagos. We also find power-law distributions for species abundances and lifetimes. (C) 2001 Academic Press.

Tags

individual-based models stability population ecology Extinction Communities Self-similarity Curves Immigration Species-area relation Large complex system