The coastal foredunes facing the sea experience extreme environmental conditions that impose strong selective pressure on the flora. Their position and their structure, in fact, subject them to stressful conditions such as the high and fluctuating salinity brought by the spray and the soil, the low water availability of the sand that does not retain it, and the great poverty in nutrients of pure sand. The dunes are also subject to the pernicious abrasion of the plants and their burial by the sand and the intense direct and reflected by the grains of sand illumination inducing high ground temperatures.