US-IALE 2018

AUTHORS: Alanis Gonzalez*, Roycemore School; Randy Swaty, The Nature Conservancy; Monika Shea, University of Wisconsin-Madison

ABSTRACT: The “tension zone” is an ecotone of varying width that runs from the northwestern corner of Minnesota to the central eastern section of Michigan. This ecotone is the meeting place of the southern prairie/savanna/deciduous forest and then northern mixed conifer/hardwood forest ecosystems. Important traits of the tension zone and terrestrial ecotones may include greater biodiversity, possible mutualistic relationships between ecosystems, and novel assemblages of species that are often on the edge of their range. Due to these factors, ecotones could be especially vulnerable in a changing climate and have considerable conservation values. Using LANDFIRE Existing Vegetation Type data we assessed how much of the tension zone has been converted to agricultural or urban land use. To assess ecosystem health we calculated the vegetation departure (VDEP) of remaining natural vegetation. The VDEP metric assesses the difference between modeled historic and mapped current vegetation composition and structure. In order to verify the historic/reference portion of our LANDFIRE-based findings we compared them with the General Land Office Survey data from the mid-1800s. This data represents trees that were present on the land at that time. Our aim with this research was to spatially assess ecological risk (i.e. conversion to agricultural and urban land uses, and VDEP) in the tension zone as a way to prioritize protection and restoration activities.