The propagation of disturbances in ecological networks.

Network science has revealed that the architecture of many complex biological, physical, and social systems facilitates the direct and indirect propagation of disturbances. Ecological disturbances, such as species extinctions and the disruption of their interactions by environmental change drivers, may propagate across space and time. However, the scale over which these impacts propagate remains largely unknown. Ecological disturbances vary in their propagation pathways and effects on network structure and functioning. The characteristics of species and of their interaction networks and metanetworks contribute to predicting the rate and extent to which different disturbances spread across ecological communities. The identification of spatial or temporal boundaries for ecological networks is key to capturing metanetwork dynamics and the scale over which disturbance effects can propagate. Despite the development of network science, we lack clear heuristics for how far different disturbance types propagate within and across species interaction networks. We discuss the mechanisms of disturbance propagation in ecological networks, and propose that disturbances can be categorized into structural, functional, and transmission types according to their spread and effect on network structure and functioning. We describe the properties of species and their interaction networks and metanetworks that determine the indirect, spatial, and temporal extent of propagation. We argue that the sampling scale of ecological studies may have impeded predictions regarding the rate and extent that a disturbance spreads, and discuss directions to help ecologists to move towards a predictive understanding of the propagation of impacts across interacting communities and ecosystems. [ABSTRACT FROM AUTHOR]