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A. M. Sharaky
in Chad, the Central African Republic, and Sierra Leone (World Bank 2015). The
economy of Dakhla Oasis is based on agriculture. The people in the Dakhla Oasis
use about 520 springs and ponds. Some of water sources have recently dried out, and
others use electric pumps (Sefelnasr 2007).
Sand dune encroachment occurs mainly in desert areas with fragile lands, loose
sands, limited precipitation, and hot and dry climate. It risks to form nonproductive
lands and reduce the ability of cultivated land to produce crops, and livestock. Some
cultivated lands decreased their productivities because of soil degradation and desertification. Soil erosion reduced yield in Africa ranging between 2 and 40%, with an
average loss of 8.2% (Eswaran et al. 2001). Most of the lands in Africa are classified
as arid lands (Lancaster 1996). Africa includes hyper arid region in the world called
the Sahara and the deserts of Kalahari and Namib.
The present chapter studies the sand dune movement in the Dakhla Oasis in the
Western Desert as a case study for the African drylands. Dakhla Oasis is located in the
middle of the Western Desert (see Fig. 1). Many researchers studied sand movement.
Their researches led to develop mathematical equations for calculations of the sand
Fig. 1 Locations of Dakhla and Farafra Oases (Source Landsat image, https://visibleearth.nasa.
gov/images/71790/the-nile-egypt)
A. M. Sharaky
in Chad, the Central African Republic, and Sierra Leone (World Bank 2015). The
economy of Dakhla Oasis is based on agriculture. The people in the Dakhla Oasis
use about 520 springs and ponds. Some of water sources have recently dried out, and
others use electric pumps (Sefelnasr 2007).
Sand dune encroachment occurs mainly in desert areas with fragile lands, loose
sands, limited precipitation, and hot and dry climate. It risks to form nonproductive
lands and reduce the ability of cultivated land to produce crops, and livestock. Some
cultivated lands decreased their productivities because of soil degradation and desertification. Soil erosion reduced yield in Africa ranging between 2 and 40%, with an
average loss of 8.2% (Eswaran et al. 2001). Most of the lands in Africa are classified
as arid lands (Lancaster 1996). Africa includes hyper arid region in the world called
the Sahara and the deserts of Kalahari and Namib.
The present chapter studies the sand dune movement in the Dakhla Oasis in the
Western Desert as a case study for the African drylands. Dakhla Oasis is located in the
middle of the Western Desert (see Fig. 1). Many researchers studied sand movement.
Their researches led to develop mathematical equations for calculations of the sand
Fig. 1 Locations of Dakhla and Farafra Oases (Source Landsat image, https://visibleearth.nasa.
gov/images/71790/the-nile-egypt)