Predicted Vegetation Changes

The rate at which species must move to keep pace with climate change—termed ‘climate velocity’—is predicted to be highest in relatively flat interior continental areas such as the western Great Lakes Region (Loarie et al. 2009). Temperature increases for a range of IPCC scenarios are projected to be 3-9°C in this region by the end of the 21st Century (Wuebbles & Hayhoe, 2004; Galatowitsch et al., 2009), much faster than the slow rate of climate change during the Holocene (Fig. 2). This would lead to northward shifts of tree ranges of 300-500 km (Prasad et al., 2008).  The seven forested parks in our study, near the current prairie-forest border, could be transformed to open savanna in the next century (Frelich and Reich 2010, Gonzalez et al. 2010, Fig. 1). Boreal plant and animal species would be lost or become very rare within each park, persisting only in thermal refugia. Species that might disappear include at least 10 boreal tree species that are currently foundation species for ecosystem function.

We will develop a model to predict the locations of the three biome types in the study area: boreal forest, temperate forest and prairie/savanna under current climate conditions, and then also apply the model for each downscaled future climate scenario to bracket the range of possibilities for future juxtaposition of boreal, temperate and prairie/savanna species with climate change. We will apply similar models to the southern range limits of the major boreal tree species to predict where they will be present for future climate scenarios. In areas where boreal forest is predicted to disappear, we will also examine the potential of temperate forest and savanna species to replace boreal forest.