The Erg of Bilma is a

dune sea An erg (also sand sea or dune sea, or sand sheet if it lacks dunes) is a broad, flat area of desert covered with wind-swept sand with little or no vegetative cover. The word is derived from the Arabic language, Arabic word ''ʿarq'' (), meaning ...

(Arabic: ''

erg The erg is a unit of energy equal to 10−7joules (100 nJ). It originated in the Centimetre–gram–second system of units (CGS). It has the symbol ''erg''. The erg is not an SI unit. Its name is derived from (), a Greek word meaning 'work' o ...

'') in the

Ténéré The Ténéré (Tuareg: Tenere, literally: "desert") is a desert region in the south central Sahara. It comprises a vast plain of sand stretching from northeastern Niger into western Chad, occupying an area of over . The Ténéré's boundaries are ...

desert region of the south central

Sahara Desert , photo = Sahara real color.jpg , photo_caption = The Sahara taken by Apollo 17 astronauts, 1972 , map = , map_image = , location = , country = , country1 = , ...

. The Erg of Bilma stretches southwest from

Fachi Fachi is an oasis surrounded by the Ténéré desert and the dunes of the Erg of Bilma in eastern Niger, placed on the western edge of the small Agram mountains, Agram mountain outcropping. It has an estimated population of 2,000 people. It is a ...

and the

Tibesti Mountains The Tibesti Mountains are a mountain range in the central Sahara, primarily located in the extreme north of Chad, with a small portion located in southern Libya. The highest peak in the range, Emi Koussi, lies to the south at a height of and i ...

. On the west it is bounded by the

Aïr Mountains The Aïr Mountains or Aïr Massif ( tmh, Ayăr; Hausa: Eastern ''Azbin'', Western ''Abzin'') is a triangular massif, located in northern Niger, within the Sahara. Part of the West Saharan montane xeric woodlands ecoregion, they r ...

in north central

Niger ) , official_languages = , languages_type = National languagesBilma Bilma is an oasis town and commune in north east Niger with, as of the 2012 census, a total population of 4,016 people. It lies protected from the desert dunes under the Kaouar Cliffs and is the largest town along the Kaouar escarpment. It ...

, continuing on to the

Chad Chad (; ar, تشاد , ; french: Tchad, ), officially the Republic of Chad, '; ) is a landlocked country at the crossroads of North and Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic ...

ian border. It surrounds on three sides the oasis of

Bilma Bilma is an oasis town and commune in north east Niger with, as of the 2012 census, a total population of 4,016 people. It lies protected from the desert dunes under the Kaouar Cliffs and is the largest town along the Kaouar escarpment. It ...

, southernmost of a north–south string of oases of the

Kaouar The Kaouar (or Kawar) is a series of ten oases in the southern Sahara in northeast Niger, covering about from north to south, and east to west. They are on the eastern edge of the Ténéré desert, between the Tibesti Mountains in the east a ...

rise. The Erg covers an area of approximately . At its southernmost edge, some of the dunes have been stabilized by the growth of vegetation, allowing human cultivation of crops like

millet Millets () are a highly varied group of small-seeded grasses, widely grown around the world as cereal crops or grains for fodder and human food. Most species generally referred to as millets belong to the tribe Paniceae, but some millets al ...

and

sorghum ''Sorghum'' () is a genus of about 25 species of flowering plants in the grass family (Poaceae). Some of these species are grown as cereals for human consumption and some in pastures for animals. One species is grown for grain, while many othe ...

on the slopes.

History

The ancient

Bornu Empire Bornu may refer to: * Bornu Empire Bornu may refer to: * Bornu Empire, a historical state of West Africa * Borno State Borno State is a state in the North-East geopolitical zone of Nigeria, bordered by Yobe to the west, Gombe to the southwest ...

Fezzan Fezzan ( , ; ber, ⴼⵣⵣⴰⵏ, Fezzan; ar, فزان, Fizzān; la, Phazania) is the southwestern region of modern Libya. It is largely desert, but broken by mountains, uplands, and dry river valleys (wadis) in the north, where oases enable ...

caravan routes had to cross the dunes of the erg south of Bilma as the last major obstacle before reaching the

sahel The Sahel (; ar, ساحل ' , "coast, shore") is a region in North Africa. It is defined as the ecoclimatic and biogeographic realm of transition between the Sahara to the north and the Sudanian savanna to the south. Having a hot semi-arid c ...

. While that traffic largely ceased after 1820, trade though the erg of Bilma continues from the

Lake Chad Lake Chad (french: Lac Tchad) is a historically large, shallow, endorheic lake in Central Africa, which has varied in size over the centuries. According to the ''Global Resource Information Database'' of the United Nations Environment Programme, ...

region and the

Termit Massif The Termit Massif (Termit Mountains or simply the Termit) is a mountainous region in southeastern Niger. Just to the south of the dunes of Tenere desert and the Erg of Bilma, the northern areas of the Termit, called the Gossololom consists of ...

on a small scale..

References

External links

*
Prof. Dr. R. Baumhauer
a

has produced a number of papers on the Geography and Paleogeography of the Erg of Bilma.
Surviving the Sahara
: National Geographic, December 2002.

Sahara {{Niger-geo-stub

History

See also

References

Further reading

External links