Frequently disturbed ecosystems are characterized by resilience to ecological disturbances. For example, longleaf pine ecosystems are not only exposed to frequent fire disturbance but also depend on this feature to sustain biodiversity. We utilized empirical metrics of interaction diversity to support the idea of response diversity as it confers redundancy and resiliency in the fire-dependent longleaf pine ecosystem. While the concept of interaction diversity has been discussed for decades, especially in the context of conservation and global change, we sought to use empirical data to quantify interaction diversity at ecologically relevant scales to examine its role in resiliency. This was accomplished by recording interaction diversity parameters across a time since fire gradient as well as at hierarchical spatial scales.
Results/Conclusions
We found that local scale patterns of interaction diversity are associated with short-term resilience. The greater amount of turnover in the diversity of interactions in the most frequently burned stands provides functional redundancy, conferring immediate resiliency to disturbance by fire. As fire frequency decreases, interactions become more specialized and less resilient. Furthermore, these local scale patterns of interaction diversity contribute to broader scale patterns, bestowing longer-term ecosystem resiliency. These findings are important, because they demonstrate that fire not only maintains species diversity but it also maintains the important interactions that contribute to ecosystem function and services, such as biological control. As global change continues to alter disturbance cycles as well as species richness, these relationships between disturbance and diversity are important to understand.