الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
The present investigation is under taken to study the pedological and mineralogical characteristics of the soils of EL-Beheira Governorate located in the Western part of Nile Delta region to criteria on soil genesis, formation and classification of this region. The area is bounded by longitudes 29° 50’ West and 30° 40’ East and latitudes 30° 4’south and 31° 30’ north. It is characterized by the presence of the geomorphological units.
1-Recent Nile alluvial plain 2-Fluvio - marine plain 3-Desert plain
In this study twenty soil profiles were selected to represent the prevalent three geomorphic units. These profiles were morphologically described in the field, and some seventy two soil samples representing the morphological variations throughout the entire depth of each profile were collected for analysis.
In this accord, the collected samples were evaluated for the physical, chemical and mineralogical stand points. In view of the laboratory investigations, the following results were obtained.
1-Physical and chemical properties :
a) Soils of the Recent Nile alluvial plain have a clay or sandy clay loam textured Class. CaCO3 content is very low and ranges from 0.46% to 5.1%. Organic matter content is very low, not exceeding 2.9%. Soil reaction is neutral to strongly alkaline, where pH values range between 7.3 and 8.6, electrical conductivity of the soil paste extract ranges from 0.8 to 27.9 dS/m indicating that the soils are non saline to strongly saline. The dominant Soluble cations are sodium and or calcium, while the potasium ions are the least abundant. The anionic compositions dominated by SO: followed by Cr and HCO3 while CO3 ions are almost absent.
b)Soils of Fluvio-marine plain are characterized by variable texture, from sand to clay. The wide variations in soil texture reflect clear lithological discontinuities. CaCO3 Content varies from 0.5% to 36.57% with an irregular distribution pattern with depth. Organic matter is very low and not exceeding 2.4% reflecting the arid climatic conditions.
Soil reaction changes from neutral to moderately alkaline, where pH values ranged from 7.3 and 8.39.The soils are non to slightly saline where EC values range from 1.1 to 27.9 dS/m Soluble cations are dominated by Na’ followed by Ca” and or Mg”, while K+ is the least abundant cation. The anionic composition is dominated by SO4 followed by Cl , while HCO 3 is the least abundant anion.
c)Soils of the Desert plain, the have the soil texture ranged from sandy to clay loam. CaCO3 content rang as from 3.5 % to 18.9%. Organic matter content is extremely low not exceeding 0.8%.
Soil reaction is mildly alkaline to moderately alkaline as the pH values range between 7.6 to 8.0.EC values range from 1.0 to 4.0 dS/m indicating that the soils are non saline. The cationic composition of the soil saturation extract follows the order Na’ > Mg” > Ca” > IC. The anionic composition is characterized by the dominance of SO4- followed by CI and HCO3—.
2-Grain size analysis:
Applying sorting and skew ness indices, on the soil profiles of Recent Nile alluvial and Fluvio-marine plain. Sorting values indicate that the sediments are poorly, moderately and well sorted and skewed towards fine and coarse suggesting that transportation and deposition of parent materials by water or water and wind actions.
Sediments of the soils of Desert plain are well and moderately sorted sediments and skewed towards coarse, suggesting the transportation and deposition of parent material by wind or water and wind actions.
3- Microelements status in the studied soils: 3-1- Total microelements content:
Shows that Fe content ranges from 13583 to 57304, 15790 to 56930 and 4809 to 16890 ppm. In the Recent Nile alluvial, Fluvio-marine plain and Desert plain, respectively, while Mn content varies from 452 to 938, 316 to 816, 107 to 73 8ppm, respectively.
With regard to total Zn content, it ranges from 39 to 99 ppm. In the soils of Recent Nile alluvial, from 18 to 66ppm. In the Fluvio-marine plain. And from 9 to 24 ppm in the Desert plain.Total Cu content varies from to 57, 8 to 56 and 4 to I2ppm in the soils of Recent Nile alluvial, Fluvio-marine plain and Desert plain, respectively.
The vertical distribution of trace elements is discussed in light of the statistical measures, i. e. , weighted mean, trend and specific range suggested by Oertel & Giles (1963).
3-2- DTPA extractable microelements :
The different soil contents of available Fe, Mn, Zn and Cu were extracted by DTPA. The results obtained for the soil extractable Fe ranged from 2.82 to 46.92, 1.88 to 33.26 and 0.7 to 16.56 ppm. in the Recent Nile alluvial, Fluvio-marine plain and Desert plain, respectively. Available Mn ranges from 0.5 to 8.2, 0.78 to 7.88 and 0.14 to 2.26ppm. in the soils of Nile alluvial, Fluvio-marine and Desert plain.
With regard to available Zn the data reveal that the lowest amounts of available Zn were found in Desert plain soils contain (0.06 — 0.4 ppm.) followed by (0.06-1.66 ppm.) in the Fluvio-marine soils, while the highest amounts recorded in the Recent Nile alluvial ( 0.12 — 10.5 ppm ).
DTPA-extractable Cu ranges from 0.28 to 11068, 0.20 to 13.92 and 0.12 to 1.24 ppm. in the Recent Nile alluvial, Fluvio-marine plain and Desert plain, respectively.
4-Mineralogy of the sand fraction: 4-1- Light minerals:
Quartz predominates the light minerals content, its content ranges from 92.6 to 98.6%. Feldspars are next in abundance, their contents ranges from 1.4 to 7.4%.Plagioclase predominates the feldspars followed by orthoclase and microcline.
4-2-Heavy minerals:
The results indicate that Opaque minerals ( mainly iron oxides) are the most common minerals. The non-Opaques are mainly dominated by amphiboles, pyroxenes and epidote. On the other hand, the metamorphic minerals (garnet, Kyanite, staruolite and sillimanite) and to some extent, the ultrastable minerals (Zircon, futile and tourmaline) constitute a considerable portions of the non-opaques, while the rest of minerals are found in less pronounced amounts.
4-3-Uniformity of soil parent materials:
The data of frequency distribution of resistant minerals and weathering ratios leads to the conclusion that the soils are heterogeneous either due to their multi-origin or due to the subsequent variation along the course of sediments, and therefore, are considered young from the pedological view point.
5- Mineralogy of the clay fraction:
X-ray diffiactograms of the studied clay fraction reveal the predominance of smectite ( montmorillonite) over all the clay minerals followed by Kaolinite. The other associated clay minerals illite, chlorite, vermiculite and palygroskite are detected with less pronounce occurrence. The identified accessory minerals are mainly dominated by quartz followed by feldspars, while gypsum, calcite, apatite and dolomite are detected in trace amounts.Soil classification
Soil classification was carried out following the most recent American System ”Soil Taxonomy”, Soil Survey Staff, (1975 and 1999 ), down to the family level, the studied soils have been classified into three soil orders,namely Entisols, Vertisols and Aridisols.
1-Order: Entisols
Sub order: Fluvent
Sub group : Typic Torrifluvents (profileslOand 11).
: Vertic Torrifluvent(profiles1,3,and 17). Sub order: Psamments.
Sub group : Typic Torripsamments (profile 4).
Sub order: Orthents.
Sub group : Typic Torriorthents (profile 8 ).
2-Order: Vertisols.
Sub order: Torrerts.
Sub group : Typic Haplotorrerts (profiles 2,
5,6,14,16,7,12,13,18,19,and20 ). Sub group : Typic calcittorrerts (profile 15).
3-Order: Aridiso
Sub order: Calcids.
Sub group: Typic Haplocalcids ( profile 9 )