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Scaling in a Multispecies Network Model Ecosystem

Ricard V. Sole·David Alonso·Alan McKane
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Abstract

A new model ecosystem consisting of many interacting species is introduced. The species are connected through a random matrix with a given connectivity. It is shown that the system is organized close to a boundary of marginal stability in such a way that fluctuations follow power law distributions both in species abundance and their lifetimes for some slow-driving (immigration) regime. The connectivity and the number of species are linked through a scaling relation which is the one observed in real ecosystems. These results suggest that the basic macroscopic features of real, species-rich ecologies might be linked with a critical state. A natural link between lognormal and power law distributions of species abundances is suggested.

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Ricard V. Sole, David Alonso, Alan McKane. 1999-07-23. Scaling in a Multispecies Network Model Ecosystem. https://arxiv.org/abs/adap-org/9907010

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