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The magnificence of the studied desert soils has been increased fast due to scale efforts to bring additional areas under the agricultural utilization projects in recent decades. This target will be achieved throughout identifying the soil limitations and the possible adverse environmental effects, and then executing a suitable technique to correct them as well as that has become associated with increasing soil supplying power for soil nutrients or moisture and maximizing the productivity of the grown plants. So, the current work has been undertaken to evaluate the constraints for ameliorating these desert soils under the prevailing environmental conditions of the Western Desert region. The proposal scheme should be overcome three aspects, i.e., soil taxonomy, soil evaluation and soil suitability for certain crops. The studied area is commonly found as desert outskirts at the northern-east side of Wadi El Natrun, and it is situated between latitudes 31 o 15and 31 o 40 -N, and longitudes 30 o 00and 30 o 20 -E. With special reference to set up the soil characteristics of the studied area, the technique of space images interpretation plays an important role for tracing the prevailing geomorphic units as well as identifying the promising sites for agricultural purposes.The obtained data of the Images of Landsat interpretation, using Thermatic Mupper (TM 5, SPOT 90), revealed that the area under consideration is occupied by four main landforms or geomorphic units namely Deltalic stages, Wind blown sand deposits, River terraces and Wadi El Natrun complex. Also, these soils are surveyed, according to Taxonomic system of USDA (1999 and2001), and mapped into five taxonomic units: a. Typic Torriorthents (Deltaic stages), b. Gypsic Aquisalids (Wind blown sand deposits), c. Typic Haplocalcids (River terraces), d. Typic Calcidgypsids and e. Typic Haplogypsids (Wadi El Natrun complex). According to land evaluation system undertaken by Sys and Verheye (1978), the studied soils are affected by many of limiting factors, i.e., topography, wetness, soil texture and salinity/alkalinity, with variable intensity degrees. Also, the current suitability of the studied soils assessed three classes of moderately suitable soils (S2, Deltalic stages), marginally suitable soils (S3, River terraces and Wadi El Natrun complex) and unsuitable soils (N1, Wind blown sand deposits). By executing the suitable soil improvement practices, the potential suitability classes assessed two classes, i.e., moderately suitable (S2, Deltalic stages, River terraces and Wadi El Natrun complex) and marginally suitable soils (S3, Wind blown sand deposits). Land suitability for certain crops can be achieved by matching the ratings of land characteristics with the crop requirements in different suitability levels as proposed by Sys et al. (1993). It could be identified both supreme and subsequent prior potential suitability for specified utilizations with the representative soils developed on the different geomorphic units of the studied area for the selected twenty...

The current work aimed to evaluate the effect of some micronutrients (Fe, Mn, Zn and Cu) in mineral (sulphates) and chelated (-amino acids and -EDTA) forms added to soil in solely or in combined treatments with both organic composts (wheat residues and cattle wastes) and sulphur on grain and straw yields as well as their contents of such micronutrients for wheat-maize cropping sequence in a calcareous soil, with special reference to the effects of these treatments on available soil contents of these micronutrients. To achieve this target two field experiments were conducted on a calcareous soil located at the eastern edge of Tamia district, El Fayoum Governorate, and cultivated with winter wheat (Sakha 69) followed by summer maize (single cross 10 hybrid) to verify the results obtained during growing season of 2003/2004 under surface irrigation system.The data obtained reveal that the experimental soil is characterized by secondary calcic formations in compacted phase, especially in the uppermost layer, and micronutrient deficient. The soil is classified at the family level as Typic Haplocalcids, clayey, mixed, hyperthermic. Also, its capability was evaluated as marginally suitable (S3ws), with a moderate intensity degree (rating = 60-85) for all the identified soil limitations (wetness, soil texture, soil depth and CaCO 3 content). The results showed an improvement occurred in available micronutrient contents (Fe, Mn, Zn and Cu) in the studied soil as a result of the applied treatments, with different magnitudes depend on their effective roles, nature of chemical composition, as shown in the following descending order: mineral micronutrients + organic composts > micronutrients + sulphur > chelated micronutrients > organic composts + sulphur > mineral micronutrients > organic composts > sulphur.The favourable conditions of the combined treatments with organic composts or sulphur are commonly achieved by lowering soil pH and forming organo-metalic compounds. The chelated micronutrients (-amino acids and -EDTA) represented the next superior form due to a higher portion of these compounds still in maintained active forms for uptake by plant roots.The beneficial effects of the studied treatments were actually reflected on increasing the grain and straw yields of wheat and also extended to the next cultivated maize. In addition, the positive effects of the studied treatments are more attributed to improve the efficiency of micronutrients uptake according to their effective roles. Moreover, the micronutrients response of Fe, Mn, Zn and Cu to accumulate in the grain and straw tissues showed a closely relationship to their corresponding available contents in the treated soils.

The current study is of importance to support the local knowledge, concerning the best use of land and available water resources whether be under demand for agricultural utilization or be planned for later on use. Also, it represents an environmental problem at a new industrial city of El Asher min Ramadan area, i.e., the utilization of contaminated industrial wastewater used as an irrigating source for an adjacent agricultural desert area. In that concerning a hazardous that may cause toxic effects on both crop products and human health. Consequently, it should be executed a suitable soil amendment practices to minimize such possible adverse effects. In this connection, two soil sites are of sandy loam and sandy clay loam texture grades as well as 7 and 13 years land use periods in agricultural utilization, respectively, and directly irrigated with contaminated industrial wastewater after being passed through an oxidation pond were undertaken in this study. These soils are encompassing by the aeolian deposits, and classified as Typic Torriorthents, coarse (soil site 1) or fine loamy (soil site 2), mixed, thermic. According to a parametric evaluation system, they could be evaluated as moderately (S2s1s3s4) and highly suitable (S1s1s3s4) for soil sites 1 and 2, respectively, with an intensity degree for each of soil texture, CaCO 3 and gypsum as soil limitations lies in the range of slightmoderate (rating = 90-75).An elemental composition analysis was executed on each of the studied two soil sites, besides the industrial wastewater used for irrigating them, and it was found that available contents of Fe, Mn, Zn, Cu, Pb, Cd and Ni within the permissible limits, with one exception for Cd content whose laid at the upper critical limit for soil site 1 and exceeded it in soil site 2, since the soluble Cd content in the available irrigation water source is more than the permissible limits. That means both the studied irrigation water source and soils are Cd-polluted ones. Thus, Zn-soil amendment was a matter of concern in this work due to support the antagonism phenomenon between Cd and Zn through their uptake by plant roots. Hence, a field experiment was conducted on the chosen two soil sites, where wheat (Triticum astivum, c.v. Giza 163) and barley (Hordeum vulgare, c.v. Giza 126) were sown during the winter season of 2005-2006. The investigated soil plots were irrigated with industrial wastewater in randomized complete block design, with three replicates. The agricultural management practices were conducted as usual. Zn was applied to soil plots under study at three rates, i.e., 0, 5 and 10 kg Zn fed -1 in form of zinc sulphate (22 % Zn) as soil application.The obtained results showed a beneficial effect of Zn, especially at a high Cd level on the grown plants. Also, applied Zn caused more

The current study is an attempt to define the relationship between originated mineral constituents and essential nutrients that could be derived into the formed soils under cyclic-formation sequences at El Fayoum depression. To achieve this target, four soil sites were selected to represent some soils developed on the main parent materials, i.e., the Nile alluvium, recent lacustrine, desert formations of siliceous (aeolian) and carbonatic in nature (Eocene limestone). The obtained results showed wide variations in the characteristics of the studied soil sites, i.e., topographic-sequence (-40 to +25 m), soil texture grades (sandy to clay), CaCO 3 content (1.12 to 38.54%), ground-water table depth (65 to >150 cm), soil salinity (ECe=1.65-23.96 dS/m) and sodicity levels (ESP=3.42-32.68), consequently they differ in their soil taxonomic units and the suitability classes for agricultural purposes. Wetness, soil texture, CaCO 3 , gypsum and salinity/alkalinity are the most effective limitations for soil productivity, with an intensity degree ranged between slight and very severe (rating >90 and <40). Also, the suitability classes of the studied soils ranged between moderately (S2s1s4n) and not suitable (N1ws1s4) for the current condition as well as highly (S1s1) and marginal suitable )S3s1s4).The polarizing microscopic examination for light and heavy minerals of sand fraction as well as the x-ray diffractions of both silt and clay fractions were also suggested to identify the different nutrient-bearing mineral assemblages. Moreover, soil constituent-bound nutrient forms, i.e., exchangeable, organic matter, carbonate, manganese oxides, amorphous & crystalline iron oxides and the residual content were identified due to their crucial importance for soil fertility status. Most of P amounts in soil were bound with organic matter fraction, with maximum values reached about 26 and 20% of total bound P-forms for both the fluvial sediments and carbonatic desert formation, respectively. The greatest value of K bound with organic matter fraction was about 15% of total bound K-forms for the recent lacustrine sediments. Ca and Mg were more combined with carbonate fraction, especially in the carbonatic desert formation, with greatest values of more than 39 and 68% of the total bound forms, respectively.Relatively high S-amounts of about 30-31% of the total bound Sforms were bound with organic matter fraction of the Nile alluvial and lacustrine sediments. A pronounced amount of bound micronutrients was more obvious in the Nile alluvial sediments, where Fe was more combined with amorphous and crystalline iron oxide fractions (i. e., about 24 and 40 %, respectively); Mn was more bound with MnO 2 and both iron oxides fractions with maximum values of 23.54 and 30.75 %, respectively; Zn was mostly combined with the amorphous and crystalline iron oxides fractions with about 22 and 37%, respectively; whereas, Cu was also Atif A. Awadalla; et al.