Ouadi Rimé – Ouadi Achim nature reserve
Coordinates: 15 ° 31 ' N , 19 ° 40' E
The Ouadi Rimé – Ouadi Achim nature reserve is located in the center of Chad , mostly in the province of Batha and Borkou and extends over 77,950 km² and was established in 1969. This makes it one of the largest nature reserves on the African continent .
The nature reserve extends over three vegetation zones of the Sahel zone , the desert with the dune areas of the Erg du Djourab in the north, the semi-deserts with the grass savannahs of the South Sahara grass and shrub savannah vegetation zone and the areas of the Sahel acacia savanna in the south. In general, the area distribution is given as 23% grass savannahs and 76% desert and semi-deserts. The grass savannahs are interspersed with trees, these are dominated by the gum arabic tree ( Acacia senegal ), the desert date ( Balanites aegyptiaca ), Combretum glutinosum and Boscia senegalensis . Characteristic grass species of the savannah are Aristida mutabilis , Chloris prieurii and Cenchrus biflorus and the herbs Limeum viscosum , Indigofera hochstetteri and Blepharis linariifolia .
Endangered species in the nature reserve are the Damagazelle ( Gazella dama ), the Dorcas gazelle ( Gazella dorcas ), the red-fronted gazelle ( Gazella rufifrons ), the Mendes antelope ( Addax nasomaculatus ) and the cheetah ( Acinonyx jubatus ). For the saber antelope ( Oryx dammah ), which became extinct in the wild , the nature reserve was one of the last retreats.
The area of the nature reserve is relatively flat without major elevations, on the eastern border are the Ennedi mountain range and the Wadai highlands , from which a number of Ouadis lead and irrigate the area seasonally.
Precipitation falls from July to September and is very unevenly distributed. In the south there is an average of 413 mm, in the center approx. 205 mm and in the north approx. 14 mm rain per square meter per year.