Details
about the Tassili N’Ajjer National Park
The Tassii N’Ajjer National Park was created in 1972,
then extended through successive decrees until 2001, finally
covering over 8 million hectares. It varies in altitude from
1150 to 2158 metres (3770 to 7080 feet) and the desert stands
at an average altitude of 1500 metres (4920 feet) in the north
and north-west, 1800 metres (5900 feet) in the centre and south.
It is between 80 and 300 kilometres wide (50 to 190 miles).
Tassili means “Mountain massif crowned with plateaus.” Tassili
N'Ajjer means plateau of chasms. The Park comprises two geomorphic
units:
- sandstone plateau
- mountainous volcanic ridge.
The plateau
The plateau is of extremely broken terrain towards the north,
its north-facing cliffs cut by several deep gorges and steep-sided
watered valleys running northward into sands. The red to black-weathered
sandstone has been deeply eroded into forests of 20-30m pillars
(65 to 100 feet) like ancient ruins and rises to the south-west-facing
escarpment above the shifting dunes of the Erg d'Admer and Erg
Tihodaine.
The ridge of relatively recent volcanic rock, the
Adrar massif, rises 2158m (7080 feet) in Mt.Akao and is crossed
at a few aqbas (passes) only.
There are springs and 300 permanent
gueltas (pools) on the plateau, and in the north-flowing
Oued Imirhou 20km of water sometimes runs for six months.
Another semi-permanent river is on a tributary, Oued Iherir,
where secreted travertine forms natural dams and pools which
cascade from one level to another. Near Amguid on the western
edge there is a huge crater .
The climate
The plateau is hyper-arid, very exposed and barren, but there
are sheltered more humid micro-climates where relict Mediterranean
fauna and flora survive. The annual rainfall is scant and
variable, with a mean of 25mm (1 inch), locally occasionally
150mm (6 inches). The plateau’s summer temperature range
is between 20º-30ºC (68 to 86°F) and the winter
range is between 31º-1ºC (34 to 88°F); snow is
recorded on the peaks. The annual mean is 20.3ºC (69°F)
at 1,100m (3600 feet) but in summer Djanet at this elevation
at the foot of the southern escarpment has experienced 50°C
(122°F).
To see the daily weather in the Djanet area, click here
Vegetation in the Tassili N’Ajjer National Park
The Tassili N'Ajjer plateaus, owing to their elevation and
the humidity of deep shaded valleys, possess relict Mediterranean
as well as Sudanese and Saharan vegetation. The most notable
Mediterranean species is the endemic Saharan cypress, the only
conifer of the central Sahara. There are only some 153 left
in the world, about a 100 of them scattered in the 'Valley of
the Cypresses' northeast of Djanet. They grow between 1000-1800m
(3280 to 5900 feet) and are extremely drought-resistent; all
are old, some perhaps over 2000 years old !
Fauna in the Tassili N’Ajjer National
Park
Fauna is mainly composed of insects and reptiles; mammals
are disappearing: “gundi” desert mice, antelopes,
jackals... Depending on migration fluxes, some palearctic birds
make a stop, to take advantage from the plateau’s relative
humidity.
Cultural heritage of the Tassili N’Ajjer
National Park
The eastern and north-eastern part of the National Park harbours
frescoes from different periods, especially in Sefar, Tamrit
and Tin Tazarift among the stone forests. Some of the most
beautiful neolithic engravings in the Sahara are to be found
near Djanet. In the northern part of the Wadi Djerat canyon
are 30 kilometres (20 miles) of rocks engraved with human
and animal figures, some of them life-size (hippopotamuses,
buffaloes, rhinoceroses and giraffes). |