The Inland Western Desert of Egypt

Abstract

Outside the oases of the Western Desert, five desert zones along a precipitation gradient were distinguished. In addition to the well-known semi-desert and full desert zones in the very north, three zones of extreme desert show a significant differentiation where the “accidental vegetation” occurs as precipitation is so low and falls so irregularly and no permanent vegetation exists. The accidental vegetation along two transects, the northern along Siwa Oasis–Mersa Matruh road and the southern along the Dakhla Oasis–Farafra Oasis road, was botanically explored, through their vegetation characteristics and soil attributes. The only known five populations of the endangered spinescent shrub, Randonia africana along Siwa Oasis–Mersa Matruh road, were examined with respect to their vegetation composition and soil features. Randonia africana reaches its easternmost limit of distribution in Egypt along this road. The oases are the most prominent features of the Western Desert of Egypt. A common irrigation pattern and habitat types around these wells were recognized and described. Floristically, this study confirms the separation of the northern oases (Siwa and Bahariya) in the limestone or white desert from those in the southern (Farafra, Dakhla and Kharga) in the sandstone desert. Vegetation and environment in the inland salt marshes of Siwa and Dakhla Oases and the saline lakes of Wadi El-Natrun were also studied.