What\u27s a Town to Dune: Can Vegetation be Used to Determine the Success of a Constructed Coastal Sand Dune?

Tybee Island, GA constructed large-scale dunes along its beaches, and we conducted a study to evaluate the most effective revegetation methods for sand accumulation. The objective of this study was to assess how well this dune project restored ecological function to Georgia’s most visited beach. We established two planting assemblages in high and low densities across the newly constructed dune. Assemblage 1 applied the planting design created by Tybee, and Assemblage 2 took into account functional roles of each species. Treatments were compared with each other (4 treatments, each n=6), unvegetated sites on the constructed dune (n=3), and a pre-existing dune (n=6). Five months after installation, 95% of plants survived, including 99% of large plants (individuals \u3e 10 cm2 at planting) and 94% of small plants (\u3c10 \u3ecm2). Plants in high density sites were half as likely to suffer mortality as those in low density sites. Canopy cover of small plants increased to almost 5 times their original measure over 3 months but cover of large plants stayed nearly the same. Bare sites experienced 0.2 + 0.5 cm of erosion over the 7-month study while the vegetated sites accumulated 3.2 + 0.2 cm of sand