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Predicting the stability of large structured food webs.

ABSTRACT: The stability of ecological systems has been a long-standing focus of ecology. Recently, tools from random matrix theory have identified the main drivers of stability in ecological communities whose network structure is random. However, empirical food webs differ greatly from random graphs. For example, their degree distribution is broader, they contain few trophic cycles, and they are almost interval. Here we derive an approximation for the stability of food webs whose structure is generated by the cascade model, in which 'larger' species consume 'smaller' ones. We predict the stability of these food webs with great accuracy, and our approximation also works well for food webs whose structure is determined empirically or by the niche model. We find that intervality and broad degree distributions tend to stabilize food webs, and that average interaction strength has little influence on stability, compared with the effect of variance and correlation.

SUBMITTER: Allesina S

PROVIDER: S-EPMC4525179 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Predicting the stability of large structured food webs.

Allesina Stefano S Grilli Jacopo J Barabás György G Tang Si S Aljadeff Johnatan J Maritan Amos A

Nature communications 20150722

The stability of ecological systems has been a long-standing focus of ecology. Recently, tools from random matrix theory have identified the main drivers of stability in ecological communities whose network structure is random. However, empirical food webs differ greatly from random graphs. For example, their degree distribution is broader, they contain few trophic cycles, and they are almost interval. Here we derive an approximation for the stability of food webs whose structure is generated by ...[more]

PMID: 26198207

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