COS 132-5 - Perturbation intensity and the stability of ecological networks

Thursday, August 10, 2017: 9:20 AM
E145, Oregon Convention Center
Qiang Yang1,2, Jose M. Montoya3, Andrew L. Jackson1,2 and Ian Donohue1,2, (1)School of Natural Sciences, Trinity College Dublin, Dublin, Ireland, (2)Trinity Centre for Biodiversity Research, Trinity College Dublin, Dublin, Ireland, (3)Theoretical and Experimental Ecological Station, CNRS, Moulis, France
Background/Question/Methods

Understanding the factors that underpin ecological stability is fundamental to the conservation and management of ecosystems. The biggest challenge in studying ecological stability is its complexity, which arises from its multidimensional nature and the multiple scales of biological organization at which it can be measured. Experimental studies have demonstrated that relationships among the various components of stability are not fixed, but can vary in both strength and nature when systems are perturbed. However, we lack understanding of the generality of this phenomenon and the mechanisms underpinning it. Here, we use simulated model communities to explore how the relationships between three key components of ecological stability - resistance, resilience, and invariability – vary with the intensity of perturbations.

Results/Conclusions

We show that the relationships among stability components tend to weaken – and that stability thereby becomes more complex – along a gradient of increasing perturbation intensity. Moreover, this is a very general, though not universal, phenomenon, occurring across a wide range of realistic network structures, likely driven by an increased prevalence of nonlinearity in community dynamics as perturbation intensity increases. These findings comprise a fundamental advance in our understanding of ecological stability and demonstrate the importance of quantifying multiple components of stability simultaneously.