Qattara Depression
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The Qattara Depression (Arabic: منخفض القطارة 'Munkhafad al-Qattarah') is a desert basin within the Libyan Desert of north-western Egypt. The Depression, at 133 m below sea level, contains the second lowest point in Africa (See also: Lake Asal). The Depression covers about 7,000 square miles (18,000 km²), and at its maximum is 80 km in length and 120 km in width. The bottom of the depression consists of a salt pan.
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[edit] Environment
Within the Depression there are saline marshes under the northwestern and northern escarpment edges, and extensive playas that flood occasionally. The major oasis in the depression, Moghra oasis, is uninhabited and has a 4 km² brackish lake, including a Phragmites swamp. Salt marshes also occur and occupy approximately 300 km², although in some areas, wind blown sands are encroaching. About one-quarter (26 percent) of the 19,500 km² area is occupied by playas, which are comprised of hard crust and sticky mud, and which are occasionally filled with water.
Groves of Acacia raddiana represent the only permanent vegetation, growing in shallow sandy depressions. The Acacia groves vary widely in biodiversity and rely on runoff from the rainfall and groundwater to survive.
The Depression is an important habitat for the Cheetah, with the largest number of recent sightings being in areas in the northern, western, and northwestern part of the Qattara Depression, including the highly isolated, wild oases of Ein EI Qattara and Ein EI Ghazzalat, and numerous Acacia groves both inside and outside the depression.
Gazelles (Gazella dorcas and Gazella leptoceros) also inhabit the Qattara Depression, being an important food source for the Cheetah. The largest gazelle population exists in the southwestern part of the Qattara Depression within a vast area of wetlands and soft sand. The area is 900 km², includes the wild oases of Hatiyat Tabaghbagh and Hatiyat Umm Kitabain, and is a mosaic of lakes, salt marshes, scrubland, wild palm groves and Desmostachya bipinnata grassland.
Other common fauna include the Cape Hare (Lepus capensis), Egyptian Jackal (Canis aureus hupstar), Sand Fox (Vulpes rueppelli) and more rarely the Fennec Fox (Vulpes zerda).
Barbary sheep (Ammotragus lervia) were once common throughout but now are believed to be extinct, with the last set of sheep horns being discovered in 1927. Other extinct species from the area include the Scitmar-horned Oryx (Oryx dammah), Addax (Addax nasomaculatus) and Bubal Hartebeest (Aclelaphus buselaphus).
There are no human settlements in the Qattara Depression. However the Depression is inhabited by the nomadic Bedouin people and their flocks, with the Moghra oasis being important in times of water scarcity and dry seasons.
[edit] World War II
During World War II, this was a notable geographic feature which was considered to be impassable for the majority of military vehicles, notably tanks. Its presence shaped the Battle of El Alamein. The features that made the Depression so impassable includes its salt lakes, extremely high cliffs or escarpments and Fech Fech. The cliffs in particular abutted the edge of the El Alamein battlefield.
The 1958 movie Ice-Cold in Alex features the Depression during World War II.
[edit] Hydro-electric possibilities
The area is composed of sand dunes and salt lakes in a tear drop shaped formation with the point of the drop facing east and the broad deep area at the south west end. The large size of the Quattra Depression and the fact that it falls to a depth of 132 m below mean sea level has led to several proposals to create a massive hydro-electric project in northern Egypt rivaling the Aswan High Dam. The proposals all call for a large channel or tunnel being excavated from the Quattra due north about 80 km to the Mediterranean Sea. Water would flow from the channel into a series of hydro-electric penstocks which would release the water at 90 m below sea level. Because the Quattra is in a very hot dry region with very little cloud cover the water released at the 90 m level would spread out from the release point across the basin until evaporating from solar influx. Because the depression is so deep and broad, a great deal of water would be let in to maintain the artificial salt sea at the 90 m level and as the water evaporates more sea water would be sent through the penstocks to generate more electricity.
[edit] References and external links
- Annotations. Central University Libraries at Southern Methodist University. Vol. VI, No. 1, Spring 2004.
- Manlius, M., Menardi-Noguera, A. and Andras Zboray, A. (2003). Decline of the Barbary sheep (Ammotragus lervia) in Egypt during the 20th century: literature review and recent observations. J. Zool. (London) 259: 403–409.
- Nora Berrahmouni and Burgess, Neil (2001] Saharan halophytics (PA0905). World Wildlife Fund; online.
- Saleh, M.A., Helmy, I. and Giegengack (2001) The Cheetah, Acinonyx jubatus (Schreber, 1776) in Egypt (Felidae, Acinonychinae). Mammalia 65 (2): 177-194.
- Mediterranean-Qattara Hydro-electric Proposal
