Soil as a part of the environment receives pollutants from all types of human activities. Heavy metals originating from various organic waste sources and industrial activities accumulate in the soil surface, and their fate depends not only on the types and amounts of waste applied, but on soil properties. Furthermore, soils differ in their retention power for various heavy or trace elements. Twelve soil samples were selected from different sites irrigated with industrial and sewage wastes at Helwan city (Cairo Governorate) in the north and El-Saff (Giza Governorate) in the south. Separation of clay, silt and sand fractions were carried out. Chemical analyses of trace elements in the form of total and available contents (Fe, Mn, Zn and Pb) were determined in each fraction. The obtained results show that the average amounts of heavy metals in different fractions are related to the particle size of the soil especially the fine fraction. Heavy metals content was always in the surface layers higher than sub-surface. All metals were highest in clay fraction followed by silt and sand fractions respectively. This investigation discussed the importance of the fine fractions in the accumulation of heavy metals by coordination number in the lattice structure

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The current work aims at employing the advanced techniques; GIS and computerized mathematical models for land evaluation, to assess the land capability and suitability of large areas. The area of El-Ismaillia Governorate was chosen as a study area. Sixteen soil profiles, that covered most of the soil types of the area, were selected and characterized. The characterization results were input to ALES-Arid land evaluation software. The outputs revealed that the land capability class C3 (Fair) included most of the soils of the study area where, it covered almost 72% of the total area under investigation. The soils belonged to land capability C4 (Poor) occupied about 21% of the entire area of the governorate. These soils had several limitations but severer than those of C3.The land suitability for the studied crops revealed that most of the soils belong to suitable S1 and moderately suitable S2 for wheat and barely. In the case of maize and rice, however the soils were found to be marginally, conditionally suitable and actually unsuitable. The soils of the region were mostly suitable for alfalfa. Most of the soils in the area were suitable to moderately suitable for sugar beet with few areas of marginally to conditionally suitable. The area belonged to marginally suitable class for sunflower. While the faba-bean showed mostly conditionally suitability in the area.

Water scarcity is one of the most important problems facing humanity in various fields such as economics, industry, agriculture, and tourism. This may push people to use low-quality water like industrial-wastewater. The application of some chemical compounds to get rid of heavy metals such as cadmium is an environmentally harmful approach. It is well-known that heavy metals as cadmium may induce harmful problems when present in water and invade to soil, plants and food chain of a human being. In this case, man will be forced to use the low quality water in irrigation. Application of natural materials instead of chemicals to remove cadmium from polluted water is an environmental friendly approach. Attention was drawn in this research work to use some natural minerals as zeolite, bentonite and montmorillonite to adsorb cadmium element from polluted water. Various concentrations of cadmium in solutions 10, 30 and 50 ppm were treated with three different ratios of each mineral; 1, 3 and 5% (W/V). The obtained results proved that increasing the ratio of amendments to 5% increased Cd adsorption from solution particularly at 50ppm Cd. Zeolite obtained the highest ratio of adsorption (47.90 ppm), followed by montmorillonite (44.99 ppm) and the lowest was bentonite (38.97 ppm). Therefore, it can be recommended that addition of zeolite is the most favorable material to remove Cd element from polluted water.

Abstract:The objective of this study was to determine the potassium (K) release kinetics of sandy soil sample representative soil of Egyptian new reclaimed areas as affected by treatments of different rates of compost and chemical fertilizers applied individually or mixture of both type sand the effect of two irrigation regimes i.e. 80 and 60% of water requirements IR. Four mathematical models (power function, Elovich, parabolic diffusion and first-order) were used to fitted the data describe K desorption reactions involving 168-hr cumulative reaction time. Comparison of the models using the coefficient of determination (r 2 ) and the standard error of the estimate (SE) indicated that the Elovich and the power function equations overall displayed the best fitted ones. The first-order rate and for less extent, parabolic diffusion equation were less fitted to describe the kinetic data. The constants of the best fitted models represent the rate of K release indicated that all treatments applied to soil gave high and significant increase in rate of K release compared to the control (untreated soil). According to the same constants values, the organic fertilizer applied was the lowest one, meanwhile the chemical one was the highest values, the mixture treatments values, however, were in between the chemical and organic treatments. In addition, the 80% of IR gave the best water management in having both high K adsorption from used soil and significant K uptake by corn plant.