Sand dune ecology describes the biological and physico-chemical interactions that are a characteristic of sand dunes.
Sand dune systems are excellent places for biodiversity, partly because they are not very productive for agriculture, and partly because disturbed, stressful, and stable habitats are present in proximity to each other. Many of them are protected as nature reserves, and some are parts of larger conservation areas, incorporating other coastal habitats like salt marshes, mud flats, grasslands, scrub, and woodland.