The studied area is located between latitudes 26° 49` 26= & 26° 56`14=
North and longitudes 31° 30`41= & 31° 41`48= East Fig (1).
Total space of studied area is 233 km2. The aim of this study is to evaluate
the physiographic soil units including soil classification and its suitability for
agriculture.
The studied area has almost flat to undulating topography. The soils are
deep sand to sandy clay loam with dominance of coarse texture and high gravel
content in most of soil profiles with some stones in the old terraces and fans and
outwash plain units. All studied soils have also low gypsum content and moderate
calcium carbonate content, whereas some soils of old terraces have calcic
diagnostic horizon. Soil salinity levels varied between non-saline into highly
saline.
The physiographic units of studied soils were attributed as:
(1) Old colluvial terraces. Including soil taxonomic units;
- Typic Haplocalsids, Sandy skeletal, mixed, hyperthermic.
(2) Wadi bottom. Including soil taxonomic units;
- Typic Torriorthents Sandy skeletal, mixed, hyperthermic.
(3) Wadi plains. Including soil taxonomic units;
- Typic Torriorthents Sandy, mixed, hyperthermic.
- Typic Torriorthents, Coarse-loamy, mixed, hyperthermic.
(4) Fans and outwash plains. Including soil taxonomic units;
- Typic Torriorthents Sandy-skeletal, mixed, hyperthermic.
Current suitability of soil physiographic units could be categorized into
three classes as; moderately suitable (S2) for some soils in wadi bottoms and wadi
plains, marginally suitable (S3) in fans and outwash plains and some soils of wadi
bottom and wadi plain, and not suitable (N1) for old colluvial terraces.
Data of potential suitability levels reveal that the soils of wadi plain have
the highest suitability levels followed by wadi bottoms, fans and outwash plains
and old colluvial terraces, respectively.
The potential land suitability for certain crops could be classified as follow;
(a) Highly suitable (S1) in wadi plain soils for alfalfa and olives and in wadi
bottom soils for olives.
(b) Moderately suitable (S2) in soils of;
- Wadi plain for wheat, barley, maize, cotton, sunflower, sorghum, onion, banana,
citrus, guava and mango.
- Wadi bottom for maize, alfalfa, tomato, watermelon and citrus.
- Old colluvial terraces and fans and outwash plains for olives.
(c) Marginally suitable (S3) in soils of;
- Wadi bottom for wheat, barley, cotton, sorghum, sunflower, onion, banana,
guava and mango.
- Fans and outwash plains for maize, cotton, sesame, sunflower, alfalfa, sorghum,
onion, tomato, watermelon, citrus, guava and mango.
- Old colluvial terraces for maize, sesame, sunflower, alfalfa, sorghum, tomato,
watermelon, citrus and mango.
(d) Not suitable (N) in soils of;
- Fans and outwash plains for wheat, barley and banana.
- Old colluvial terraces for wheat, barley, cotton, onion, banana and guava.