الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 168 |  |  |
| | | from | 168 | | |
Abstract
West El-Mawhoob - Abo Monqar area is one of the virgin areas in the Western
desert regarding their land, water resources and characteristics.
This area is located at West El-Mawhoob and Abo Monqar, over approximately
450,000 feddan, Western desert, Egypt, At latitude between 25º 30\ 00\\ : 26º 05\ 00\\
N and longitude 27º 55\ 00\\ : 28º 15\ 00\\ E. Its elevation ranges between 100:300
meters above sea level. It is far about 600 km from Cairo.
Aims of the present study are:
1- Assessing the dominant soil physical, chemical, and nutritional characteristics of the
studied soil area,
2- Recognizing and classifying the main soil types,
3- Identifying the dominant clay minerals in the studied soils using X-Ray diffraction
technique,
4- Estimating the capability and suitability of lands for different uses,
5- Creating a base maps for land resource management in a trial to encourage new
settlements establishment.
Climatologically, Dakhla oasis condition has a summer time with a temperature
as high as the tropics. This makes it possible to grow tropical plants. While in winter
time, the mild heat makes it favorable to grow the plants of temperate region.
Geologicaly, El- Dakhla formation is dominant one that consisting of shale,
marl and clay with intercalations of calcareous sandy and silty beds. It forms the major
thickness of the succession that overlies the Duwi formation and underlies the
Paleocene limestone beds along the scarp face from South El- Kharga to Abo Monqar.
It also covers parts of the plain to the West of El- Dakhla and is exposed in the shallow
depressions in the Abo Tartor-El Kharga flsh plateau. The tripartite subdivision of El-
Dakhla formation in El- Kharga area keeps to gross lithological aspects throughout the
various areas in El-Kharga- Abo Monqar stretch, and reflects repeated sea level
fluctuations during its deposition. The chosen of West El-Mawhoob and Abo Monqar area may be called as ”The
region of plateaus, depressions, plains, sand dunes and sand seas,” since these are the
predominant features. However, they do not show any specific distribution pattern, the
sand dunes (linear and barchan) and sand sea extend nearly in the West and South sides
of the area.
Water supply of the studied area at West El-Mawhoob and Abu-Monqar is
derived from underground bed of sandstone. The ground water appears to flow to the
surface entirely through artificial passages, i.e., bore – holes. Springs are few and far in
between as controlled by the thickness, impermeability and extent of the red clay as
proved by borings. The bore – holes may be conveniently divided into two classes:
ancient and modern.
Twenty soil profiles representing the main geomorphic units were described
and soil samples were collected. The morphological description indicates that soils
differ in depth from very shallow, shallow, moderately deep and deep. Also differ in
texture from light, medium to heavy texture. Massive structure is the predominant
ones. Soil color ranges from reddish yellow to brown . Analytical results were used to
study soil characteristics, classification and land capability classification as follow:
1- Particle size distribution indicates that soils texture varies widely from sand
to clayey. However, sandy texture is the most common textural class. Cation exchange
capacity (CEC), field capacity (FC), wilting point (WP) and available water (AW) vary
widely corresponding to texture classes and / or the presence of considerable amounts
of amorphous inorganic materials.
2- Chemical composition of the soil saturation extract indicates that soils have
different salinity levels ranging from low to extremely saline. Soil reaction varies
widely from neutral to strongly alkaline. Organic matter content and total nitrogen are
generally very low. CaCO3 content indicates slightly calcareous to extremely
calcareous nature. Gypsum content is mostly detected in all soils with significant
quantities.
3- Identified clay minerals content in the soils of the Pediplain is dominated
with smectite group (montmorillonite) followed by kaolinite, while at the soil subsurface illite is recognized with less dominancy than kaolinite. In soils of
secondary horizontal bedscarp, karstified platforms and solutional depression smectite
group (montmorillonite) is dominated and followed by kaolinite. Clay minerals in the
plateau soils are dominated by smectite group (montmorillonite) followed by kaolinite
in the subsurface and deepest layers, while at the surface layers smectite group
(montmorillonite) dominates, followed by chlorite, while kaolinite disappeared.
Moreover, in the deeper layers, chlorite clay mineral is the most abundant and followed
by kaolinite.
4- Application of soil taxonomy (2010) for classifying the studied soils
indicated that they it were placed in one order, namely Entisols. Soil classification
continued systematically to the sub greatgroup levels as follow:
Typic Torrifluvents, Typic Torripsamments, Typic Torriorthents. Lithic
Torripsamments, Lithic Torriorthents, Lithic Quartzipsamments and Typic
Quartzipsamments.
5- Land productivity indix were calculated for all profiles and found to be
ranged between 80.2 % for poor land productivity class (P4) and 19.8 % for fair land
productivity class (P3) according to Sys et al. (1991-I).
According to the soil properties, natural and environmental circumstances at the
studied area, the following agricultural development plan can be Suggested:
1. Shallow and very shallow soils can be cultivated by shallow rooted fodder
crops,
2. Deep and moderately deep soils can be cultivated by commonplants known
in the adjacent areas to the studied one,
3. Cultivation of some cash crops that can adapt the environmental
circumstances such as medicinal and aromatic plants,
4. All cultivated plants should be tolerant to salinity, drought and have low
evapotranspiration and water requirements,
5. Cultivation of the wind breakers, to combat sand dunes encroachment,
6. Construction of some livestock industrial projects,to supply soils with
organic manure, 7. Recycling of plant and animal wests to be resupplied to the soil for
improving their chemical, physical and fertility properties,
8. Applying the agricultural biotechnology to avoid environmental
contamination,
9. Dividing the area into sectors, each is served by groundwater wells taking
into consideration to leave enough space between each well and another to
avoid of the dropdown of water levels,
10. Improving the infrastructure at the study area.