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peak closest to the high tide line is classified as the primary dune (Dubois 1977). On the
leeward side of the primary dune, shells and other materials can be visualized. This sediment
becomes trapped when overwash cannot clear the dune peak upon retreat. Behind the primary
dune, a depression occurs, protected from wind and salt spray, commonly referred to as a swale.
The depressed swale can fill with freshwater during a storm event (Oosting 1954). Beyond the
swale, as deposited by wind and overwash, peaks can be seen once more (Figure 1). These peaks
are known as backdunes and generally lead into the maritime forest (Oosting 1954). The
saltwater marsh can be found behind the maritime forest. The concentration of this research will
be located in the inner, outer, and dune beach areas of the shore ecosystem. The system will be
further divided into microhabitats: foredune, dune, swale, and backdune.

Figure 1. The dune microhabitats of Fort Fisher, North Carolina (after Hancock 2009).
The dune system is an extreme environment. Beachfaces, driftlines, foredunes, and dune

peaks experience high levels of salt spray, light irradiance, and surface soil temperatures as high

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