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Al Maţarīyah, Egypt

The northwestern coast of Egypt represents one of the highest-priority regions for future development. Two contiguous basins were chosen from the northwestern coast for this research: El Zarraqa and El Harraqa basins. The main objective of the present study is to provide geomorphologic and geological data in order to work on the water potentiality development in the study area. The obtained data through the present study reveal that, although the two studied basins are close to each other, they are not compatible with all features. The morphometric parameters reveal that the studied basins have opportunities for surface runoff occurrence and also for groundwater recharge through infiltration process. The geology of the study area is dominated by sedimentary rocks of Tertiary and Quaternary ages. The study area has favorable conditions for groundwater accumulation, where this area receives an average annual precipitation of 151.95 mm, which provides the opportunity for groundwater recharge. The hydrogeological investigations reflect that two groundwater aquifers (Middle Miocene and Pleistocene) are recorded in the El Harraqa basin, and only the Middle Miocene aquifer is recorded in the El Zarraqa basin. The Middle Miocene aquifer needs more hydrogeophysical investigations to explore its potentialities where its rocks have a wide distribution and are mainly fractured. The difference in groundwater salinity in both aquifers accompanied by different hydrogeologic data confirms that the carbonate aquifer in the studied basins is heterogeneous and has anisotropic characters. The current research set up a proposed plan which includes multiactivities for the protection and development of the water resources. © 2014, Saudi Society for Geosciences.

Twenty four non-lactating goats (Age=3.5±0.08 years; Balady goats, n=12 and Shami goats, n=12) were used to evaluate the effects of long-term nutrient restriction on digestion and energy utilization. Six animals of each goat breed were fed a concentrated mixture and alfalfa hay diet (50:50 as DM basis) to meet metabolizable energy (ME) of maintenance (MEm, CON). The other six animals were fed 50% of this amount relative to actual BW (RES). Animals were individually housed for a 90-day period and then moved to metabolic cages in two sets of 12 animals each, three per treatment and breed for each set. Total Energy expenditure (EE) was estimated by a heart rate (HR) monitor for 48 h after its individual calibration by oxygen consumption with a face mask open-circuit respiratory system. Body weight and digestibility were negatively affected by long-term restricted feeding, without differences in digestibility between goat breeds. Energy expenditure was greater for CON vs. RES (417 vs. 355 kJ/kg BW0.75/day respectively, P<0.001) and lower for Balady goats compared to Shami goats, particularly in terms of RES intake treatment (312 vs. 399 kJ/kg BW0.75/day respectively, P<0.01). As a result, the energy balance (EB) was similar for both goat breeds on treatment CON, while it was greater (P<0.05) for Balady goats than Shami goats when they received RES treatment (-133 vs. -208 kJ/kg BW0.75/day respectively, P<0.01). In conclusion, Balady goats, but not Shami goats, have the ability to reduce their EE in order to improve their EB as a mechanism of adaptation when their ME intake is restricted below MEm requirements. © 2016 Elsevier B.V.

Abou-Shady A.,Desert Research Center
Electrochimica Acta | Year: 2016

Reclaiming salt-affected soil in arid and semi-arid countries is currently considered a substantial challenge because of water supply deficiencies. Traditionally, salts are removed from soil using either continuous or intermittent washing, which consumes considerable amounts of water. Our motivation for this study is to develop a process for decreasing the reclamation period and total amount of water, and improving the sustainability of reclamation. Recently, we have developed a new generation of soil electro-remediation techniques known as the perforated cathode pipe soil electrokinetic remediation (SEKR) system (PCPSS) for heavy metal removal. PCPSS was investigated for reclaiming salt-affected soils collected from the El-Sallam canal region Egypt. In the present study, enhancement of Na+ removal was firstly investigated using a Taguchi Approach orthogonal array (L9OA). The results indicated that the influential factors improved Na+ removal in the following order: cathode pipe operating time > voltage > cathode gap > hydrostatic head; additionally, the vertical removal above the cathode gap was operating time > hydrostatic head > voltage > cathode gap. A confirmation experiment demonstrated that Mg2+ removal was as high as 41.7% followed by Na+ with 23% removal. Ca2+ removal was the lowest (6.6%), likely due to the formation of insoluble CaSO4. K+ also showed low removal (8.4%), likely because of its comparatively low concentration. The removed cations show the following sequence: Mg2+ > Na2+ > K+ > Ca2+. A large percent of Cl- was removed (53.3%), whereas SO42- showed the lowest removal (5.1%). The accumulative electroosmosis flow was proportional to the voltage followed by operating time, hydrostatic head, and cathode gap, respectively. © 2016 Elsevier Ltd. All rights reserved.

The use of 14C (half-life = 5,730 years) in modeling the evolution of the 36Cl/Cl ratios in groundwater is reported for the first time. The complexity of the Cl–36Cl system due to the occurrence of different Cl and 36Cl sources and the difficulty of the determination of the initial groundwater 36Cl/Cl ratios have raised concerns about the reliability of using 36Cl (half-life = 301 thousand years, a) as a groundwater-dating tool. This work uses groundwater 14C age as a calibrating parameter of the Cl–36Cl/Cl decay-mixing models of three wells from the southwestern Great Artesian Basin (GAB), Australia. It aims to allow for the different sources of Cl and 36Cl in the southwestern GAB aquifer. The results show that the initial Cl concentrations range from 245 to 320 mg/l and stable Cl is added to groundwater along flowpaths at rates ranging from 1.4 to 3.5 mg/l/ka. The 36Cl content of the groundwater is assumed to be completely of atmospheric origin. The samples have different Cl–36Cl/Cl mixing-decay models reflecting recharge under different conditions as well as the heterogeneity of the aquifer. © 2016 Springer-Verlag Berlin Heidelberg

El Shaer H.M.,Desert Research Center
Small Ruminant Research | Year: 2010

This review paper updates knowledge on the fodder potential of a wide range of halophytes and salt-tolerant forages. These plants can produce relatively high consumable biomass in saline areas where non-halophytic species cannot grow or have low dry matter yields. Therefore, halophytes and some other salt-tolerant plants can provide a drought reserve or a supplementary feed source under arid and semi-arid conditions. On grazing lands, the halophytes can serve as a complementary nutrients source to other conventional feedstuffs, such as Atriplex spp. and cereal straws or hays. In addition to biomass production, wide variations in palatability, chemical composition, nutritive value and animal responses to several halophytes and salt-tolerant forages have been reported in the literature. Some of these species could be valuable sources of minerals and or nitrogen. However, the provision of energy supplements (e.g. barley) is necessary to overcome maintenance and or moderate production requirements of sheep and goats fed on halophytes and or salt-tolerant forages-based diets. Many studies showed that these plants could be used advantageously as alternative feeds to replace totally or partially common feedstuffs, thus to alleviate feeding cost. However, the presence of high contents of ash, plant secondary metabolites and non-protein nitrogen (NPN) should be taken into consideration when formulating diets containing halophytes and or salt-tolerant forages for small ruminants. Although most of feeding studies reported in this review have been carried in the Near East region, mainly in Egypt, results obtained in other regions worldwide support that feeding salt-tolerant plants and halophytes could promote livestock production systems, increase farmers' incomes and improve environmental conditions in the saline areas. © 2010 Elsevier B.V. All rights reserved.

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