St. Simons Island’s sand dunes along the beach protect the local coastline against erosion and flooding.
Held together by deeply-rooted plants and grasses, these mounds of sand anchor the coast, providing an important coastal ecosystem. Many years ago, sand dunes along the East Coast were flattened to create smooth, even beaches. However, when storms hit, the results were devastating, reducing beaches to a sliver of sand.
Sand dune systems are excellent places for biodiversity. Many of them are protected as nature reserves, and some are parts of larger conservation areas, incorporating other coastal habitats like salt marches, mud flats, grasslands, scrub and woodland.
Sand dunes provide a range of habitats for a range of unusual plants.
Other very specialized plants adapt to the accretion of sand. They survive the continual burial of their shoots by sending up very rapid vertical growth. Marram grass specializes in this. It forms and stabilizes many dunes by binding sand grains together. The couch-grass also performs this function on the seaward edge of the dunes. Marram grass and the sea rocket initiates the process of dune building, as it traps the sand.
In accreting situations small mounds of vegetation or tide-washed debris form and tend to enlarge as the wind-speed drops in the lee of the mound, allowing blowing sand (picked up from the off-shore banks) to fall out of the air stream. The pioneering plants adapted to withstand the problems of high salt contents in the air and soil.
The sand dunes are also home to sea oats.
These supple stalks catch and hold the sand, ensuring that the dunes grow. Their eight-foot roots help hold the dunes together, working overtime to protect the beach on St. Simons Island.
Please do not disturb, damage or destroy the sand dunes. Admire their beauty and appreciate the hard work they do 24/7 to protect the island’s beaches from a variety of threats.
Parts of this article came from https://en.wikipedia.org/wiki/Sand_dune_ecology.