Applied ecology in Canada's boreal: a holistic view of the mitigation hierarchy and resilience theory

摘要

Canada's boreal biome is a mosaic of forests and peatlands. These ecosystems have developed dynamically, periodically affected by disturbance events of significant spatial extent and variable severity, reducing ecosystem biomass. The same ecosystem types typically regenerate from biological legacies. However, concern is growing about the impact of these different anthropogenic disturbances, particularly compound disturbances including climate change, which open the door to shifts to alternate stable states. One strategy promoted to regulate anthropogenic disturbance is the "mitigation hierarchy" for development projects, where impacts on ecosystems are avoided, mitigated, restored, or compensated. This practical approach is not yet integrated into disturbance and resilience theory. Here, I develop an integrated view of the mitigation hierarchy, as well as resilience and disturbance theory, in a boreal context using ecosystem services to measure ecosystem state in a two-step process that first models loss of ecosystem function and then integrates the mitigation hierarchy and resilience theory. The application of this model is discussed in the context of restoration studies after different types of catastrophic anthropogenic disturbance. These studies, some of which are published in this special issue, highlight the important role of bryophytes and understory plants in setting restoration targets and developing criteria and indicators of success.