Correlated traits generate the structure and stability of multiplex ecological networks
TL;DR
A general model to study ‘multiplex networks’ of multiple interaction types generated from ecological traits shows that resilience varies systematically with trait correlations underlying the structure and strength of interactions involving key species that interconnect and therefore propagate disturbances between, subnetworks of different types of ecological interactions.
Abstract
Ecological stability and function emerge from the many and diverse types of interactions among species. Ecological networks represent the structure and strength of species interactions, but their study is often restricted to single interaction-types, likely due to an absence of models for plausibly (i.e., nonrandomly) structured ‘multiplex networks’ of multiple interaction types. Here, we present a general but mechanistic model that simulates multiplex networks using the different, but correlated, traits that determine different species interactions. We show that ecological stability varies systematically with these trait correlations by controlling the emergent complexity and positioning of strong interactions in the community. Our model provides a flexible but power tool to study multiplex networks under alternative trait-based hypotheses, offering new insights into the structure and stability of complex natural systems. One-Sentence Summary Trait correlations structure stability in complex ecological communities of multiple interaction types. Significance Statement To effectively tackle the increasing impacts of global change on ecological systems, we need to understand how species interactions may propagate or buffer disturbance, and the mechanisms by which resilience to disturbances emerge. This topic has been investigated for random communities and single interaction-type (e.g., predator-prey) networks. Yet, natural systems include many diverse types of interactions, and feedbacks between them mediate how species and ecosystems respond to global change. Here, we present a general model to study ‘multiplex networks’ of multiple interaction types generated from ecological traits. We show that resilience varies systematically with trait correlations underlying the structure and strength of interactions involving key species that interconnect, and therefore propagate disturbances between, subnetworks of different types of ecological interactions.