Authors: Jacquelyn Ferguson*, University of South Carolina, Jean Taylor Ellis, University of South Carolina, Anthony Stallins, University of Kentucky
Topics: Coastal and Marine, Biogeography, Geographic Information Science and Systems
Keywords: coastal geomorphology, dunes, vegetation, functional types, GIS, depositional lag time, aeolian, dune-builders, dune-stabilizers
Session Type: Paper
Presentation File: No File Uploaded
Coastal dunes provide substantial shoreline protection against coastal hazards. This study explores the role that vegetation has on influencing aeolian deposition. Vegetation can be categorized based on its topographic impact related to two predominant functional types: dune-builders and dune-stabilizers. This field-based study seeks to provide the framework for vegetation classification into functional types, and uses that schema to analyze the relationship between the spatial structure of vegetation and dune morphology. For one year, topographic and vegetation data were collected over 55 alongshore meters of recovering incipient foredune at Isle of Palms, South Carolina. Data were collected over ten transects that averaged 20 m in length every six weeks. Vegetation data were sampled using quadrat analysis and classified by functional type based on a supervisory method. Topography was characterized using a total station and integrated in GIS to produce digital elevation models. Analyses were performed to determine depositional lag time—the amount of time that passes from the first observation of a spatially-contiguous functional type to the first observed topographic response. First, topographic data were aggregated based on depositional lag time. This provided a set of observations to to analyze change throughout the time series and for cumulative change over the entire study. Visualizations of the relationships between depositional lag times and plant functional types suggests that there is a spatio-temporal relationship between aeolian deposition and vegetation that scales up to influence the larger morphology of the dune.