North Saharan steppe and woodlands

North Saharan steppe and woodlands
The North Saharan steppe and woodlands is a desert ecoregion, in the deserts and xeric shrublands biome, that forms the northern edge of the Sahara. It extends east and west across Northern Africa, south of the Mediterranean dry woodlands and steppe ecoregion of the Maghreb and Cyrenaica, which is part of the Mediterranean forests, woodlands, and scrub biome. Winter rains sustain shrublands and dry woodlands that form an ecotone between the Mediterranean climate regions to the north and the hyper-arid Sahara Desert ecoregion to the south.
Geography
The North Saharan steppe and woodlands covers in Algeria, Egypt, Libya, Mauritania, Morocco, Tunisia, and Western Sahara.
Climate
The climate in this ecoregion is hot and dry in the summer but cooler with some rain in the winter. Atlantic depressions sometimes penetrate inland between October and April. Rainfall is erratic, but averages in the north and in the south. During the summer, temperatures regularly rise to and evaporation far exceeds precipitation.
Ecology
There are varying habitats in the ecoregion including sandy systems, rocky plateaus, wadis, depressions and mountains. Each has its own characteristic species and there is considerable endemism of both plants and animals in the area.
Flora
Plant communities include steppes of grasses, herbs and low shrubs, tall shrublands, and dry woodlands. Shrublands and woodlands typically grow in depressions, in the valleys of intermittent streams (wadis), and on consolidated dunes. Common trees include Vachellia tortilis, Pistacia atlantica, and Tamarix aphylla. Tall shrubs of the woodlands and tall shrublands include Retama raetam, Ziziphus lotus, Calobota saharae, and Calligonum comosum.
Plants have evolved various strategies to adapt to the dry climate and intermittent rainfall. Many herbaceous ephemeral plants, particularly in the north, germinate in January during the wet season and quickly mature and flower before they dry out in the spring.
Fauna
Small mammals endemic to the Sahara area include the four-toed jerboa (Allactaga tetradactyla), North African gerbil (Gerbillus campestris), James's gerbil (G. jamesi), pale gerbil (G. perpallidus), lesser short-tailed gerbil (G. simoni), sand gerbil (G. syrticus), fat-tailed gerbil (Pachyuromys duprasi) and Shaw's jird (Meriones shawi). Larger mammals include the dorcas gazelle (Gazella dorcas), mountain gazelle (Gazella cuvieri) and slender-horned gazelle (Gazella leptoceros). There are a variety of snakes and lizards, including two endemic species, desert agama (Trapelus mutabilis) and Natterer's gecko (Tropiocolotes nattereri). There are few amphibians, Brongersma's toad (Bufo brongersmai) being endemic to the coastal region of North Africa. Among the bird species, the Houbara bustard (Chlamydotis undulata) and Nubian bustard (Neotis nuba) have decreased in numbers because of hunting pressure.
Protected areas
Only 0.69% of the ecoregion is in protected areas. These include:
Dghoumes National Park, Tunisia
El Omayed Nature Conservation Reserve, Egypt
Iriqui National Park, Morocco
Khnifiss National Park, Morocco
Jbil National Park, Tunisia
Oued Dkouk Nature Reserve, Tunisia
Sanghr Jabbess National Park, Tunisia
Sidi Toui National Park, Tunisia
References
Deserts and xeric shrublands
Palearctic ecoregions
Ecoregions of Algeria
Ecoregions of Egypt
Ecoregions of Libya
Ecoregions of Mauritania
Ecoregions of Morocco
Ecoregions of Tunisia
Ecoregions of Western Sahara
Flora of Algeria
Flora of Egypt
Flora of Libya
Flora of Mauritania
Flora of Tunisia
Flora of Western Sahara