Fazzan is the true Sahara with extensive sand seas (erg or edeyen or egede), rocky plateaux (reg or hamada or sarir), wadis and oases. Fazzan is the land of the Tuareg. It shares its landscapes, habitats, fauna and people with southern Algeria and northern Niger. Fazzan
stricto sensu is centred on the Edeyen Murzuq, the
present depocentre of the Murzuq Basin. To the NW is the crescent-shape
Messak, an extensive outcrop of the Cretaceous Nubian
sandstones. Its escarpment to the West and NW culminates 300 m over
the gravel plains and further, the Edeyen Awbari and
Egede Wa-n-Kaza. The hamada dips about 2° towards the
Edeyen Murzuq under which it vanishes. It is incised by canyons (wadis)
and passes (tehi). The largest one, Tehi-n-Tilemsin, separates Messak
Sattafet (black) from Messak Mellet (white). Along the wadis, prehistoric
engravings among the finest in the Sahara are found.
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Depicted
habitats: |
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Awbari
lakes
Wadis in Messak |
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... Rock art, recent fossils and human artefact tell about wetter more hospitable periods. During the latest, about 6000 years ago, the area was rather similar to present day Kenya, with elephant, hippopotamus, rhinoceros and all the fauna of the African savannahs. Along the wadis, a remnant of these environments survives with Acacia and a relict fauna including for the Mammals, the Dorcas Gazelle, and insects like Macrotoma palmata (Cerambycidae) and Sterapis (Buprestidae), typical of the Sudano-Ethiopian fauna. Nowadays, Fazzan receives scarce and irregular rain full. Still rather abundant near Algeria, the climate quickly gets dryer going east. In Messak, the last very important rainfall with generalised wadi floods happened in 1993. Since then most of the wadis have probably not received more than a shower every 3-5 years. Hence, in many wadis, particularly in their upper course, thorn trees are dying with the help of numerous wood borers. Althought very dry, this area is richer in Buprestids and Cerambycids than the wadis of the Tassili and the Akakus. |
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