Understanding how drivers of ecosystem change affect ecosystem dynamics is a necessary step to safeguard biodiversity and ecosystem services. In a rapidly changing world, however, it is also important to understand how these drivers might affect our ability to manage ecological communities. Despite the clear need, the inherent complexity of nature has at least complicated our ability to find solutions to many of the problems ecological communities face. Here, we show how control theory—a method commonly used in engineering to determine and supervise the state of complex systems—can provide useful ecological and management insight, while accounting for the complex structure and dynamics that determine the ecosystem state. Specifically, we use and extend this framework to investigate the manageability of ten pairs of uninvaded and invaded plant-pollinator networks. Furthermore, we introduce a novel way to identify the species that have a disproportionate potential to affect the abundance of other species in the community, and might, therefore, be prime candidates for management interventions.
Results/Conclusions
We found that to be fully controlled, invaded networks require a smaller number of management interventions than their uninvaded counterparts. However, the manageability of a pollination network is most strongly underpinned by the ratio of plants and pollinators, which in turns determine the network's degree distribution. Intriguingly, we also found that invasive species have a dominant position in every community where they are found. Furthermore, we show that their dominant position is underpinned by the asymmetry of their interactions—while the abundance of the invasive species depends only weakly on its interaction partners, their partners almost always depend strongly on the invasive species. Our results provide a theoretical explanation for the known challenges associated with the restoration of invaded communities and highlight how the design of management interventions might benefit from the use of both ecological theory and empiricism. Despite our focus, understanding how drivers of ecosystem change affect ecosystem dynamics is not exclusive to mutualistic communities. Indeed, we also discuss how the application of control theory might provide insight to a wide range of ecological questions in communities structured by different types of interactions.