Some studies predict that climate change over the next two centuries will lead to dramatic forest retreat at the prairie-forest border. Such a rapid retreat would require both the death of established, long-lived trees and a failure of new tree seedling establishment, but not enough is known about these two processes to be confident in predictions how the prairie-forest boundary will change. How the dynamics of this boundary change has important implications for the health of the timber industry, for recreational opportunities, and for ecosystem services such as carbon storage.
To gain a better understanding of how tree mortality and establishment may respond to climate change, data will be gathered at six sites along a 250 mile transect crossing the prairie-forest margin in Minnesota. The transect will span a summer temperature gradient of 3.8º C (7º F) and an annual rainfall gradient of 23 cm (9 inches). Tree ring samples will be used to relate adult tree growth and survival to carbon dioxide and climate. Deer and seed predator exclosures will help separate the impacts of herbivores and climate on seedling success. Data from the transect will be used to parameterize new statistical models of forest growth along the prairie-forest border at the decade to centuries scale in the low-fire, high deer environments likely to prevail into the foreseeable future.
Sixteen undergraduate students will develop their scientific skills and credentials as research assistants on this project, and additional students at the University of Minnesota, Morris (UMM) will have an opportunity to participate via their coursework.
