Refugia from climate change are widely considered essential for conservation and management of species and ecosystems as we know them. However, the limited potential for climatic refugia in northern ecosystems is particularly apparent, with these areas experiencing rapid rates of warming, and consequently high climate velocity, especially in flat terrain. This includes the vast North American boreal region, where large wetland complexes distributed across the landscape may provide more extensive buffering (resistance) against climate change. Furthermore, largely intact natural disturbance regimes, particularly wildfire, create a diverse landscape that may promote resilience through heterogeneity. While climatic refugia characteristics are reasonably well-understood, relatively little attention has been given to biophysical processes that may improve the resilience and resistance of forested landscapes to climate change. One example is the negative feedback to climate change provided by boreal peatlands, which readily retain high surface soil moisture and water tables. Fire refugia are also especially relevant in the boreal region, found mostly on islands and lakeshores that are buffered by extensive areas of water from fire ignition and spread. To amass the expert knowledge required to characterize and identify such potential refugia locations, we convened a workshop attended by 31 boreal scientists from a wide range of disciplines.
Results/Conclusions
Participants at the workshop jointly developed a framework to characterize refugia types of greatest relevance for the boreal region, including climatic, topo-edaphic, fire, and peatland refugia. We summarized the state of knowledge regarding mechanisms, spatial scale, geographic distribution, and potential landscape indicators. We also reviewed management implications and conservation targets, as well as the strengths, weaknesses, opportunities, and threats for each type of refugia. Our framework may be used to develop maps identifying areas of high refugia potential to inform climate-smart ecosystem management and conservation planning.