Understanding and mapping plant distributions surrounding marsh hammocks within the Georgia Coastal Ecosystems LTER
Accurate habitat mapping in salt marshes is important for both management and conservation goals, as it provides information essential for identifying sensitive areas and documenting changes over time as the result of sea level rise or human perturbations. The goal of this study is to characterize patterns of marsh plant distribution in the salt marshes surrounding back barrier islands (hammocks) within the Georgia Coastal Ecosystems LTER. In the summer of 2007 the GCE LTER surveyed over 50 hammocks of different origin and size. Sub-meter accuracy GPS units were used to map the hammock upland border and the extent of the upper marsh (from the hammock border to the upper edge of Spartina alterniflora, i.e. the marsh “halo”), and plants within the halo were characterized. Analysis of these data showed that marsh plant community composition directly adjacent to the upland border is affected by both the size and origin of the hammock. Additionally, there are significant differences in both the mean halo width and the dominant plant species in relation to hammock size and origin. I am currently using Light Detection and Ranging (LIDAR) data in combination with hyperspectral aerial imagery to map plant species to elucidate how elevation, in addition to proximity to uplands, determines marsh plant distributions.