Soil Conditions of Dakhla Oasis, Western Desert, Egypt
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Fig. 3 Field crops in Dakhla Oasis. Photo taken by authors, 2017
3.3 River Terraces
River terraces are formed as a result of sediment deposition on floodplains or adjacent
to channels by overbank sedimentation during flood events. Fluvial incision into these
unconsolidated sediments, which can be driven by changes in base level or high river
discharge, causes the development of a steep scarp face that delimits the proximal
edge of the flat terrace surface (Westaway et al. 2008). There can be various such
terraces at various statures showing previous river bed levels. The river terraces may
happen at a similar height on either side of the streams wherein case they are called
paired terraces. The soil depth river terraces is shallow as shown in Fig. 7.
3.4 Sand Dune
The process of formation of sand dunes takes a long time, where the sand dune carried
by wind for a distance depends the topography and wind speed and also obstacles
present in the region. The sand dunes take many forms according to the direction
of the wind and the existing obstacles, whether trees or weeds and others. Anyhow
the dominant sand dune in Dakhla Oasis are Crescent, star, linear, transverse and
129
Fig. 3 Field crops in Dakhla Oasis. Photo taken by authors, 2017
3.3 River Terraces
River terraces are formed as a result of sediment deposition on floodplains or adjacent
to channels by overbank sedimentation during flood events. Fluvial incision into these
unconsolidated sediments, which can be driven by changes in base level or high river
discharge, causes the development of a steep scarp face that delimits the proximal
edge of the flat terrace surface (Westaway et al. 2008). There can be various such
terraces at various statures showing previous river bed levels. The river terraces may
happen at a similar height on either side of the streams wherein case they are called
paired terraces. The soil depth river terraces is shallow as shown in Fig. 7.
3.4 Sand Dune
The process of formation of sand dunes takes a long time, where the sand dune carried
by wind for a distance depends the topography and wind speed and also obstacles
present in the region. The sand dunes take many forms according to the direction
of the wind and the existing obstacles, whether trees or weeds and others. Anyhow
the dominant sand dune in Dakhla Oasis are Crescent, star, linear, transverse and