Floristic Composition of Species Inhabiting the Threatened Oolitic Sand Dune-habitat in Egypt

Egypt is located in the arid belt with semi-arid Mediterranean coast. The characteristic maritime oolitic sand dunes stretched parallel to the sea from Alexandria westward to Mersa Matruh. This habitat prevailing highly specialized floristic composition never grows southward. Recently, the oolitic sand dune habitats threatened by urbanization expansion and global climate change, induce a notable decline in floristic composition and species richness. The present study aims at assessing the flora land vegetation of the oolitic sand dunes. The floristic composition in the surveyed area revealed a total of 116 psammophyte species (91 genera belongs to 27 families), annuals comprise 47.4% and the perennials record 40.5. The chronological analysis revealed the dominance of the Mediterranean elements either mono-, bi- or pluri-regional chorotypes that recorded 64.7% of the total number of species. The relationship between the prevailing species composition and soil variables using CCA revealed that CaCO3, organic carbon positively affected and fractions of sand & clay and chloride ions negatively controlling the species distribution. The deterioration of the oolitic habitats as a result of the construction of resorts and urbanization reported a severe decline in the vegetation and flora of the area and this expansion must be stopped.