Analyzing Susceptibility of Wetlands to Changes in Water Availability Resulting from Potential Climate Change, Acadia National Park, Maine

Presentation (pdf document)

Martha G. Nielsen, U.S. Geological Survey, Augusta, Maine, mnielsen@usgs.gov

Climate change has the potential to impact freshwater wetlands substantially. If summer and annual temperatures increase as projected, increases in evaporation may put many types of wetlands at risk of reduced water availability during the growing season. Conversely, projected increases in precipitation could result in increased ground-water recharge, which could benefit other wetland types. Reduced water availability could result in decreases in the duration of standing water and soil-surface saturation, which can influence vegetation distributions, the success of amphibian breeding, and other wetland benefits. A GIS analysis of 186 wetlands in Acadia National Park, Maine, was conducted by the U.S. Geological Survey, using available landscape-scale data for each wetland and its catchment area. Catchment areas for each wetland were mapped, and landscape variables related to the hydrologic function of the wetlands were analyzed. The landscape variables used included size of the wetland compared to the catchment size; soils data; topography; slope of the catchment; and presence of streams, rivers, and lakes or ponds as potential sources of water. Overall, 11 variables were analyzed, resulting in a score that was used to rank the wetlands from most susceptible to disruptions in water availability under projected climate change to least susceptible to disruptions.