30 30'0"E. Qarun Lake. Desert land. El-Fayoum km 30 30'0"E

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STUDY AREAS 30 30'0"E 30 40'0"E 30 50'0"E 31 0'0"E 31 10'0"E Libya Mediterranean sea EGYPT Sudan Red sea Saudi Arabia 29 30'0"N 29 20'0"N 29 10'0"N Tamia Qarun Lake Sinnoris Yousefelsdek Ibshawai

1 STUDY AREAS 30 30'0"E 30 40'0"E 30 50'0"E 31 0'0"E 31 10'0"E Libya Mediterranean sea EGYPT Sudan Red sea Saudi Arabia 29 30'0"N 29 20'0"N 29 10'0"N Tamia Qarun Lake Sinnoris Yousefelsdek Ibshawai El-Fayoum Etsa ± Wadi El rayan lakes El-Fayoum km Beni Swif River Nile Giza 29 30'0"N 29 20'0"N 29 10'0"N 30 30'0"E 30 40'0"E 30 50'0"E 31 0'0"E 31 10'0"E Figure The province of El-Fayoum is darkened on the map of Egypt, and its administrative boundaries are indicated in the enlarged image. As shown in Figure 3-21, El-Fayoum Province is composed of six districts, Tamia, Sinnoris, Ibshawai, El-Fayoum, Yousef El Sadik and Itsa. The most common economic activity in this province is agriculture; although there are also some industrial parks. Over-utilization and inadequate management of the existing resources (i.e., soil, water and land use) are the main causes of unsustainable development in the studied area. This study aims to show the possibilities of using an agro-ecological land evaluation decision support system to formulate sustainable strategies. According to the Egyptian Soil Survey Staff (1980), El- Fayoum is a natural closed depression, formed by erosion in the Eocene limestone plateau, and without external drainage. It is characterized by a direct supply of water from the Nile River. This means that without the input of Nile water, through the natural stream Bahr Yousef, the El-Fayoum depression would just be another unpopulated desert depression CLIMATE According to the climate databases of El-Fayoum Governorate, annual mean temperature is 22 o C and mean minimum and maximum temperatures are 14.5 (January) and 31.0 o C (June) respectively. Accordingly, monthly evapotranspiration rates range from 1.9 in the colder periods (January) to 7.3 mm/day in hot periods (June) (CLAC, 2010). 73

2 CHAPTER 3 The rainy season is from December to March, and total rainfall does not exceed 7.5 mm/year. The evapotranspiration rates range between 3.06 and mm/day, with an annual mean of about 6.75 mm/day, and the highest average evapotranspiration rate (10.26 mm/day) is recorded in June. Table 3-4 shows climatic parameters and climate type according to De Martonne (1926) in the El-Fayoum Depression and the surrounding desert area. Figure 3-22 shows the graphical output of climate conditions that represent the average variation of precipitation (P), temperature (Tm), potential evapotranspiration (ET 0 ) and which months are arid months, in which the actual precipitation is lower than the potential evapotranspiration (Ar i ), both inside (Figure 3-22-A) and outside (Figure 3-22-B) El-Fayoum depression. In Figure A, the input volume of irrigation water from the Nile River has been considered as rainfall. Figure Graphical representation of climate conditions of weather stations in El- Fayoum depression (A) and the surrounding area (B). (P), precipitation; (Tm), monthly mean temperature; (ET 0 ) potential evapotranspiration; (AR i ) arid months in which the actual precipitation is lower than the potential evapotranspiration. Adapted from the Climatological Survey Department (ARE, 2009). 74

3 STUDY AREAS Table 3-4. Mean temperature (Tm, o C), water supply (mm/year), aridity index (AI) and climate type according to De Martonne (1926) in El-Fayoum Depression and the surrounding desert area. Area Tm Water supply Aridity index Climate type El-Fayoum Depression Very humid Surrounding desert Arid Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum km Beni Swif River Nile Classes Nile Silt Limeston with olive shale formation Gravels mixed with sand and silt Sand dunes Gravels and sand Undifferentiated deposits Water bodies Figure Classes of lithology synthesis in El-Fayoum GEOLOGY El-Fayoum Depression is located in a marine sedimentary basin which has undergone alternating periods of erosion and deposition since the late Cretaceous period, 70 million years ago. In this sense, several authors have addressed the geological history of the El-Fayoum Depression (Beadnell, 1905; Sandford and Arkell, 1929; Ball, 1939; Caton et al., 1929; Little, 1936; Shukri and Azer, 1952; Shafei, 1960; Said, 1962; and Tamer, 1968). Figure 3-23 displays the main six 75

4 CHAPTER 3 lithological classes in El-Fayoum depression: Nile silt, limestone with shale formation, gravels mixed with sand and silt, sand dunes, gravels and sands and undifferentiated deposits. Hammad et al (1983) summarized the geology of El-Fayoum area, describing these six classes above. The El-Fayoum depression itself is formed by erosion in Middle Eocene rocks, which form the oldest exposed beds in the area and are composed essentially of gyps-ferrous shale, white marls, limestone and sand (known as Ravine beds). The southern and western parts of El-Fayoum area are also formed from Middle Eocene beds which are composed of hard white limestone, argillaceous sand and sandy shale (known as the Wadi El-Rayan formation). The northern terraces overlooking the El-Fayoum depression are essentially formed by upper Eocene materials, composed of shale and limestone in the lower beds with sand and sandstone in the upper beds (known as the Qaser El-Sagha formation). The Oligocene and Upper Eocene beds, are composed mainly of fluvio-marine variegated sands and sandstone, with alternating beds of shalemarls and calcareous grits containing silicified wood (Qatrani formation). Above the Qatrani formation, basalt intrusions fissured as a constant horizon about m thick. The northwestern parts of the area are occupied by the Lower Miocene beds. These beds are composed of sands, gravel, silicified tree trunks, sandstone and quartzite (known as Gebel El-Khashab beds). Finally, there are Pleistocene deposits, which consist mostly of gravel and sands mixed with pebbles of fluvio-lacustrine origin, while Middle Eocene deposits have accumulated at the bottom of the El-Fayoum depression TOPOGRAPHY Topography is one of the main features that shapes the El-Fayoum depression, creating a unique landscape among the cultivated areas in Egypt. It plays a defining role in soil formation, irrigation, drainage, soil conditions and land use for agricultural purposes in the region. Waterfalls for instance are one of the distinctive features of the irrigation network, reflecting the impact of topography. In general, the El-Fayoum floor slopes downwards in a north-western direction at a rate of about 2 m/km, from 143 to -53 meter above sea level (masl) at the north-western side of Qarun lake as lake as illustrated in Figure 3-24, Figure 3-25 shows slope gradient in El-Fayoum depression, which shows that this area is dominated by the flattest class. 76

STUDY AREAS Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum 0

0-20 60-80 120-143 -40 - -20 20-40 80-100 -20-0 40-60 100-120

Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum 0 5 10 20km

5 STUDY AREAS Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum km Beni Swif River Nile Elevation ( m, MSL) Figure 3-24.Elevation map of El-Fayoum. Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum km Beni Swif River Nile Slope, % < ,9 Figure Slope map of El- Fayoum. 77

CHAPTER 3 Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum 0 5 10 20km Beni Swif River Nile Slope direction Flat (-1) Northeast (22.5-67.5) East (67.5-112.5) Southeast (112.5-157.5) South (157.5-202.

7.5) North (337.5-360, 0-22.5) Figure 3-26. Slope aspect of El-Fayoum. 3.3.1 GEOMORPHOLOGY The depression is surrounded by hills and escarpments, which are steep only on the southeastern side, where the Bahr Yousef stream enters the area at El Lahun.

6 CHAPTER 3 Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum km Beni Swif River Nile Slope direction Flat (-1) Northeast ( ) East ( ) Southeast ( ) South ( ) Southwest ( ) West ( ) Northwest ( ) North ( , ) Figure Slope aspect of El-Fayoum GEOMORPHOLOGY The depression is surrounded by hills and escarpments, which are steep only on the southeastern side, where the Bahr Yousef stream enters the area at El Lahun. The area shows some major terrace areas. The first terrace between 26 (at El Lahun) to 23 masl, (El-Fayoum city), an almost flat slope which can be divided into a belt of Nile alluvial deposits which extends from El Lahun to Hauwara, but is bordered by the desert both at the north and the south, and a plateau of alluvial fan stretches out, from Hauwara to El-Fayoum city in a semi-circular shape. The second terrace is located between 23 and 10 masl, also formed by Nile deposits. The third terrace has the steepest slope in the depression, where the surface falls gradually to Qarun Lake (-45 masl) at the northwestern side (Ghabbour, 1988). 78

STUDY AREAS Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum 0 5 10 20km Beni Swif River Nile Geomorphic units Fayoum fan El Ghark basin Elevated plain Flood plain Recent lake terraces Old lake

The present depression was formed after the basin subsided around a tributary of the Nile River, allowing the Nile to break through and periodically flood the area.

7 STUDY AREAS Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum km Beni Swif River Nile Geomorphic units Fayoum fan El Ghark basin Elevated plain Flood plain Recent lake terraces Old lake terraces Older lake terraces Rock Figure Major geomorphic units in El-Fayoum depression according to Shendi (1984). The present depression was formed after the basin subsided around a tributary of the Nile River, allowing the Nile to break through and periodically flood the area. This led to the formation of a deep fertile alluvium (Said, 1993). The main landforms in El-Fayoum depression are fans, recent and old lake terraces, depressions, plains, and basins. These landforms are characterized by smooth slopes (usually < 3.5%) and low elevation, which ranges from -49 to 26 masl. According to Tamer (1968), the landscape of the El-Fayoum Depression and the adjacent areas is divided by major physiographic features, namely, the table land, the elevated gravely plains and the steepest monocline around the depression margins. Intense rock weathering played an important role in shaping and producing different geomorphological features such as escarpments capped by or 79

8 CHAPTER 3 composed of resistant rocks, or low lands (valleys, plains and depressions) formed by soft of less resistant rocks. Soil properties are affected by the weathering of underlying rocks (Tamer 1968). Furthermore, several researchers (Said, 1962; Shendi, 1984) agree that the El- Fayoum formation includes three groups of sediments of distinctly different origins: fluvial sediments, aeolian sediments, and lacustrine deposits. Figure 3-27 shows the main sediment units according to Shendi (1984). The fluvial sediments from the Nile are located within the depression and have relatively fine textures throughout the profile. Abu El Einane (1985) identified the main landforms of El- Fayoum depression according to regional geological structure, climatic factors and the nature of the prevailing parent materials into flood fan, old lake terraces (Nile alluvial deposits), recent lake terraces (Qarun deposits) and old desert terraces (desert formations) HYDROLOGY According to the Directorate of Irrigation in El-Fayoum (2009), the Province has an irrigation system, designed and constructed between 1900 and 1920 to be used for perennial irrigation. Irrigation water for El-Fayoum is supplied through the Nile River at the Assiut Barrage in Upper Egypt and is conveyed along the fringe of the Nile Valley first by the Ibrahimia canal to Dairut and then by the ancient Bahr Yousef canal to El Lahun, a distance of 380 km. Figure 3-28 describes what happens in El-Fayoum province with the (2.3 x 10 9 m 3 /year) water that is supplied by the Nile: most of it is transpired by the different crops, but there is also evaporation from the lakes, and also some evaporation from the irrigation channels. The largest lake, Qarun Lake, has a surface area of hectares, while the smaller lake Wadi El Rayan has a surface area of hectares. This large surface of open water results in inevitable loss of water through evaporation. Both lakes are considered the main sinks of drainage water for the agricultural lands in the province. Because of the specific characteristics of the El-Fayoum depression, water distribution is controlled by a system of weirs, in order to keep the water slope in the main canals relevant to land level on both sides without water erosion. Due to this topography, with average slopes of 2 m/km towards Qaroun Lake, most of the province (93%) is irrigated directly through waterfalls. Some areas of El-Fayoum show water deficits, especially at the ends of irrigation canals and especially during the dry season. 80

STUDY AREAS Lake Qarun 0.47 x 10 3 Hm 3 / year 20% Irrigation 2.3 x 10 3 Hm 3 / year 100% Wadi El Rayan 0.25 x 10 3 Hm 3 / year 11% Crop Evapotranspiration 66% Open surface Evaportion 3% Figure 3-28.

Adapted from Directorate of Irrigation in El-Fayoum (2009). Drainage water flows from south to north along the slope where it is discharged into Qarun Lake and the Wadi El Rayan Lakes (Figure 3-29).

The Wadi El- Rayan reservoir was constructed in order to decrease drainage water reaching the Qarun Lake and to serve newly reclaimed land.

9 STUDY AREAS Lake Qarun 0.47 x 10 3 Hm 3 / year 20% Irrigation 2.3 x 10 3 Hm 3 / year 100% Wadi El Rayan 0.25 x 10 3 Hm 3 / year 11% Crop Evapotranspiration 66% Open surface Evaportion 3% Figure Output of the 2.3 Hm 3 of irrigation water from the Nile River in El-Fayoum: Evaporation from Lake Qarun, Wadi El Rayan, and uncovered irrigation canals; and transpiration by crops. Adapted from Directorate of Irrigation in El-Fayoum (2009). Drainage water flows from south to north along the slope where it is discharged into Qarun Lake and the Wadi El Rayan Lakes (Figure 3-29). The drainage system in El-Fayoum consists of two major drainage canals (El-Batts and Wadi). The Wadi El- Rayan reservoir was constructed in order to decrease drainage water reaching the Qarun Lake and to serve newly reclaimed land. Approximately 65% of the drainage water (470 of 720 million m 3 /year) still reaches the Qarun lake, which is a limited reservoir. Consequently, the rise of water level in the lake affects the groundwater table in the adjacent low-lying areas. Since a few years, about one third of the total drainage water (250 million m 3 /year, 34.7%) is directed towards the El Rayan lakes. This drainage water may be reused for irrigation, either directly or mixed with fresh Nile water, this lake therefore provides double benefits for both irrigation and drainage. Based on the capacity of the canals, there are three main irrigation supply canals and two main drainage canals in El-Fayoum (Figure 3-29). Some characteristics of the system of canals are shown in Table

10 CHAPTER 3 Table 3-5. Total length of the main irrigation canals and drains in El-Fayoum Province, as calculated from original maps. Width, m Length, km Length, % Irrigation canals More than Between 10 to Between 5 to 10 1, Total 1, Drainage canals Between 10 to 25m Between 5 to 10m Total Bahr Qarun Wadi El rayan lakes Bahr Qasr Al - Banat ± El-Fayoum km Qarun Lake Masraf Al - Wadi Bahr An - Nazlah Bahr Al - Khur Masraf Al - Wadi Bahr Qasr Al - Banat Tirat Al - Jirjiyyah Bahr Sanhur Bahr Fidaymin Bahr Ibshway Bahr Al - Bashawat Bahr Mutul Bahr Naqalifah Bahr Abjij Bahr Arus Bahr Al - Gharaq Bahr Ar - Rafi Bahr Tirsa Bahr Abu Sir Bahr Sinnurais Bahr Sayf Ad - Din Bahr Wahbi Masraf Al - Bats Bahr Yusif Bahr Az - Zirbi Bahr Allam Bahr Furqus Tirat Silah Tirat Al - Ajuz Bahr As - Sirb Bahr Wahbi Beni Swif River Nile Giza Irrigation canals width, m More than 25m Between 10m to 25 Between 5 to 10 Drainage canals width, m More than 25m Between 5 to 10 Figure Irrigation and drainage canals in El-Fayoum. 82

11 STUDY AREAS SOILS The soil types in Egypt vary considerably, with fertile alluvial soils in the old Nile Valley and deep soils with gravelly and reddish subsoils making up river terraces at different reliefs. On the other hand, there are infertile soils in the peripheral (desert) areas, these include calcareous soils of various textures and noncalcareous soils, all characterized by low soil fertility and inferior soil physical, chemical and biological properties. The geographic location of the different soil types can be explained by the distance to Qarun Lake in the northwest and thereby the frequency and severity of flooding (Said, 1993). Figure 3-30 shows the soil map of El-Fayoum. The area corresponding to each soil subgroup is shown in Table 3-6. Vertic Torrifluvents are the dominant soil subgroup in El-Fayoum, covering an area of 760 km 2 (43% of the study area). Other important subgroups are Typic Haplocalcids (421 km 2, 24%) and Typic Torrifluvents (141 km 2, 8%). The rest of soil subgroups (Typic Haplogypsids, Typic Haplosalids and Typic Torripsamments) are found in small areas and all together cover approximately 11% of the study area. Most of the cultivated soils in El- Fayoum Province are deep Nile alluvial loam to clayey soils. In addition, calcareous clayey and a part from the sandy soils are found as patches in the depression edges. A general discussion of such soil types was provided by Shendi (1990) who classified the soil types in this area in five major units: Nile alluvial soils, fluviolacustrine soils, fluvio-desertic soils, lacustrine soils and desert soils. Table 3-6. Areas and percentage of soil subgroups (taxonomic units) in El-Fayoum Province. Taxonomic unit (2010) Area, km 2 Area, % Vertic Torrifluvents (SU1) Typic Haplocalcids (SU2) Typic Torrifluvents (SU3) Typic Haplogypsids (SU4) Typic Haplosalids (SU5) Typic torripsamments (SU6) Rock land (RL) Urban areas Total

12 CHAPTER 3 Qarun Lake Giza ± Wadi El rayan lakes El-Fayoum km Beni Swif River Nile Soil units (USDA, 2010) Vertic Torrifluvents (SU1) Typic Haplocalcids (SU2) Typic Torrifluvents (SU3) Typic Haplogypsids (SU4) Typic Haplosalids (SU5) Typic Torripsamments (SU6) Urban Rock land Figure Soil map, according to USDA (2010). The Nile alluvial soils occur in the south-eastern and central parts of the El- Fayoum depression, and are found on flood plains and in fans. These soils are characterized by sediments that are quite uniform in depth, with occasional soil sedimentary layering due to a history of multi-depositional patterns in aqueous environments. These soil types have secondary nodules of CaCO 3 and mica, mostly in the fine sand size, and especially in the subsoil layers. Most of these soils are moderately saline. According to USDA (2010), these soils are classified at family level as Typic Torrifluvent, fine, mixed, thermic. Fluvio-lacustrine soils are spread over a large area, covering the eastern and southern banks of Qarun Lake within the El-Fayoum depression, and are developed on landforms of moderately low and high terraces. Such soils are characterized by fine textures and shallow ground water tables, as well as a 84

13 STUDY AREAS relatively high content of CaCO 3, gypsum, organic matter and salts. These soils are classified at the subgroup level as Vertic Torrifluvents (SU1) and Typic Haplosalids (SU5). Fluvio-desertic soils occupy small areas at the outer rims of the El-Fayoum depression, especially in the eastern and western parts. These soils developed from heterogeneous parent materials which reflect the fluctuation of lithological or depositional environmental conditions during the profile formation. Therefore, soil texture is very variable. Soils are classified at family level into Typic Torripsamments, sandy, siliceous, thermic. Lacustrine soils are divided into two categories according to their depositional age and origin. Older lacustrine soils are associated with different evolutionary stages of the ancient Fayoum Lake. They are highly calcareous due the characteristics of parent materials (mostly Middle-Eocene limestone). These soils show high CaCO 3 content, and are classified at the subgroup level as Typic Haplocalcids (SU2). More recently formed lacustrine soils are located at the current shoreline area of Qarun Lake, where salinity and drainage problems are severe. Such soils are characterized by a skeletal nature due to the abundance of calcareous sediments of biological origin. These soils are classified at the family level according to their content of CaCO 3 or soluble salts into Typic Torripsamments (SU6) or Typic Haplosalids (SU5), sandy, carbonatic, thermic. Desertic soils are developed on the undulating low-relief plain, and are mainly categorized into aqueous and aeolian desert according to their origin. The aqueous desert soils are composed of shales with neoformations of gypsum and iron oxides, which confirm their origin and the geological period of the depositional environments. Chemical properties are related with humid conditions, showing low ph and negligible CaCO 3 contents. The aeolian desert soils occupy the north-eastern and western area of El-Fayoum depression, which is built up of low sand dunes or sheets. They are mainly composed of loose, moderately well sorted, sand, reflecting the contribution of aeolian-origin. These soils are classified at family level into Typic Torripsamment, sandy, siliceous, thermic. 85

16 High diversity of crops in a small farm area because of fragmentation of agricultural ownership by inheritance traditions in El-Fayoum.

18 Desert areas in Doñana National Park (Andalusia), the largest nature reserve in Europe.

20 The desert areas surround El-Fayoum depression and little vegetation can adapt itself under little hyper-arid conations.

22 Pump machine for withdrawal of agricultural drainage water poured to Qarun Lake

24 Wadi el Rayan lakes, the second reservoir of agriculture drainage water after Qarun Lake. The picture was taken from nearby highlands.

Laboratory Exercise #4 Geologic Surface Processes in Dry Lands

Page - 1 Laboratory Exercise #4 Geologic Surface Processes in Dry Lands Section A Overview of Lands with Dry Climates The definition of a dry climate is tied to an understanding of the hydrologic cycle