Okuyama Toshinori, Holland J Nathaniel
Department of Ecology and Evolutionary Biology, Rice University, Houston, TX 77005, USA.
Ecol Lett. 2008 Mar;11(3):208-16. doi: 10.1111/j.1461-0248.2007.01137.x. Epub 2007 Dec 7.
Key advances are being made on the structures of predator-prey food webs and competitive communities that enhance their stability, but little attention has been given to such complexity-stability relationships for mutualistic communities. We show, by way of theoretical analyses with empirically informed parameters, that structural properties can alter the stability of mutualistic communities characterized by nonlinear functional responses among the interacting species. Specifically, community resilience is enhanced by increasing community size (species diversity) and the number of species interactions (connectivity), and through strong, symmetric interaction strengths of highly nested networks. As a result, mutualistic communities show largely positive complexity-stability relationships, in opposition to the standard paradox. Thus, contrary to the commonly-held belief that mutualism's positive feedback destabilizes food webs, our results suggest that interplay between the structure and function of ecological networks in general, and consideration of mutualistic interactions in particular, may be key to understanding complexity-stability relationships of biological communities as a whole.
在捕食者 - 猎物食物网和竞争群落的结构方面取得了关键进展，这些进展增强了它们的稳定性，但对于互利共生群落的这种复杂性 - 稳定性关系却很少有人关注。通过基于经验参数的理论分析，我们表明结构特性可以改变以相互作用物种间非线性功能反应为特征的互利共生群落的稳定性。具体而言，群落恢复力会通过增加群落规模（物种多样性）和物种相互作用的数量（连通性），以及通过高度嵌套网络的强对称相互作用强度而增强。结果，互利共生群落呈现出很大程度上的正复杂性 - 稳定性关系，这与标准悖论相反。因此，与普遍认为互利共生的正反馈会破坏食物网稳定性的观点相反，我们的结果表明，一般而言生态网络的结构与功能之间的相互作用，特别是对互利共生相互作用的考虑，可能是理解整个生物群落复杂性 - 稳定性关系的关键。
