Vegetation and Soil Patterns at a Mountain Wetland Ecotone

Abstract

This study analyzes tree, soil, and microtopographic patterns present within the Cranberry Glades, a bog wetland complex located in the mountains of West Virginia. The Cranberry Glades are comprised of four open bog meadows, which provide unique habitat to several rare and endangered plant species. However, these meadows are filling in with trees and alder. This research is a study on the factors that may be involved in the processes and patterns influencing tree encroachment into the bog meadows across the open meadow – bog forest ecotone. To determine the patterns of infilling and the potential relationships among the trees, microtopography, and soil conditions, I collected and analyzed data on each of these factors within nine belt transects located across the ecotone. I gathered tree data on the following: location within transect, species, diameter at breast height or diameter at ground level, height class, associated microtopography, and growing conditions on 1,389 trees. Soil samples were gathered across the ecotone and analyzed for percent moisture, pH, and various nutrients and metals. I assessed historical aerial photographs to gain a temporal history on the patterns of infilling. The results indicate that trees decrease in density across the ecotone towards the peatland interior, and that trees are likely to be growing on hummock features and within tree islands. Soil properties resulted in mixed conclusions. The aerial photograph assessment revealed that trees and alders have been steadily encroaching into the open peatlands for at least the past 52 years. The finding of this research lend to increased knowledge on southern peatlands, wetland succession, and the Cranberry Glades Botanical Area.