HYDROGEOLOGICAL IMPACTS OF SAVANNA ECOSYSTEM RESTORATION AND REGIONAL CLIMATE CHANGE, AND THE POTENTIAL CONSEQUENCES FOR ENDANGERED SPECIES MANAGEMENT, IN MANISTEE NATIONAL FOREST, MICHIGAN

 The U.S Forest Service is reducing tree canopy cover in Manistee National Forest, Michigan, to restore the natural oak-savanna ecosystem in support of the endangered Karner Blue Butterfly. Long-term hydrogeological monitoring of groundwater levels and temperature was initiated to evaluate the potential effects of restoration on the local groundwater system. Hourly groundwater level and temperature data were collected by continuously recording instrumentation, periodic soil moisture data were collected on-site, and precipitation data were obtained from the National Oceanic & Atmospheric Administration. Annual groundwater recharge to the thick and permeable glacial outwash sands is dependent on a complex inter-relation among spring precipitation, snowpack melt, leaf emergence, incoming radiation, and other factors. Inter-annual groundwater recharge fluctuations show high variability in terms of amount, duration, and timing. For example, although 2014 had significantly less precipitation than in 2013, groundwater levels displayed a greater recharge response, and this coincides with the onset of canopy reduction efforts. This study focuses on developing a conceptual model of the hydrogeological impacts generated by ecosystem transformation, specifically savanna restoration. Additionally, we are positioned to document any hydrological change that may have potential consequences on the successful reintroduction of the Karner Blue Butterfly. Finally, an impact of climate change on local hydrological variability may manifest as altered groundwater recharge dynamics.