Diversity and distribution of medicinal plants in North Sinai, Egypt
The present study aims to assess plant diversity and distribution of medicinal plants in relation to environmental factors at three geomorphological districts (Mediterranean coast, anticlines, and inland) and five main habitats (salt marshes, sand dunes, sand plains, wadis, and gorges) in North Sinai. The results revealed that North Sinai harbors 281 species with high taxonomic diversity (species/genera = 1.49) and high percentage of rare and very rare species (67%). Mediterranean coastal district and anticlines district are more diverse than inland district. Medicinal plants constitute 43% of North Sinai flora. Species richness, Shannon-Weiner H, and Margalef indices measurements indicated that gorges are the most diverse habitat in North Sinai followed by wadis. Plains have intermediate diversity followed by sand dunes. The lowest diversity indices were recorded at salt marshes habitat. Beta diversity measurements, using Wilson and Schmida index (βT), indicated significant changes in floristic compositions between different habitats. The lowest changes were among sand plain, wadi, and gorge habitats. North Sinai habitats support about 100 to 120 medicinal plant associations. The main dominant species include Artemisia monosperma, Arthrocnemum macrostachyum, Lycium shawii, Retama raetam, Stipagrostis scoparia, Tamarix nilotica, Zygophyllum album, and Zygophyllum dumosum. Soil physical properties in addition to soil salinity and topographic variations are the main driving factors controlling the distribution of medicinal plants in North Sinai. About 60% of medicinal plants are threatened due to intensive collection and other human activities. The threatened medicinal plants including Acacia pachyceras, Acacia tortilis, Anastatica hierochuntica, Asclepias sinaica, Capparis spinosa, Chiliadenus montanus, Citrulus colocynthis, Ephedra alata, and Juniperus phoenicea along with their habitats should have the first priority in management and conservation plan of medicinal plants in North Sinai. Public and private involvement in management and utilization of medicinal plants in sustainable way is essential to combat human pressures on these valuable natural resources.
Key words: Conservation, diversity, habitats, human impacts, medicinal plants, vegetation.