SPATIAL ANALYSIS OF ATMOSPHERIC DEPOSITION AND TERRESTRIAL ACCUMULATION OF MERCURY WITHIN ACADIA NATIONAL PARK

Acadia National Park (ANP), located on the coastal Mount Desert Island (MDI) in Maine, lacks any major point source of mercury (Hg), but biota have some of the highest body burdens of Hg in the United States. This dichotomy has sparked research for decades and produced theories on Hg transfer dynamics between inorganic and organic pools and on Hg bioaccumulation and biomagnification across trophic levels. The island location of ANP provides a natural boundary for non-atmospheric Hg pools, and the national park setting has fostered research focused on preserving park resources. This combination of known land-use history, clear biogeochemical boundaries, and intense Hg research provides a template on which to build spatiotemporal models of Hg dynamics. Data from several independent research projects have been collated and spatially referenced within a geographic information system (GIS). This first step towards island-wide modeling included an inventory of abiotic data and landscape features from diverse sources, with particular focus on the paired research catchments within ANP. These data were evaluated for point pattern processes using basic spatial diagnostic techniques. Multiple datasets comparing different ecosystem mercury pool samples were collated and modeled as event and non-event instances in a bivariate point pattern analysis. Field sampling logistics have resulted in non-random and clustered data, complicating the process of determining point process patterns in Hg values. Preliminary results indicate that while a priori sampling distribution limits the application of standard spatial analyses, categorization of spatiotemporal neighbors can elucidate the spatial tendencies of Hg contamination.