The National Information and Documentation Centre (NIDOC) affiliated to Academy of Scientific Research and Technology(ASRT)Egyptian Journal of Soil Science0302-670154420141230Status of Heavy Metals in Soils of Assiut as Affected by the Long-Term Use of Sewage Water in Crop Irrigation: Case Study28930417910.21608/ejss.2014.179ENJournal Article20140112<strong><span style="font-size: 25.0pt; mso-bidi-font-family: ''; mso-text-raise: -2.0pt; mso-bidi-language: AR-EG;">C</span></strong> <br /> <br /> <br /> <br /> <br /> <br /><span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;">ONCERNING soil pollution with heavy metals, a survey study was carried out to evaluate the present status of Cd, Ni, Pb, Fe, Mn, Zn and Cu in agricultural soils near Assiut city. Over 40-50 years, soils were either irrigated with underground, or sewage waste water at six sites, namely El-Madabegh, Mankabad, Ellwan, Bani Hussein, Bani Ghalleb and Gahdam. Thirty-six soil profiles were dug and subsamples were taken to determine the status of the selected elements using standard methods.</span> <br /><span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;"></span> <br /><span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;">Data of this study indicate that the concentrations of Fe, Mn, Zn, Cu, Pb, Cd and Ni are present at high levels in the soils irrigated with sewage wastewater relative to that irrigated with underground water. A survey to evaluate metals uptake by the crops under agriculture at the indicated sites is needed, but the use of sewage wastewater in irrigation at the indicated sites needs to be justified.</span> <br /> <br /><span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;"></span>The National Information and Documentation Centre (NIDOC) affiliated to Academy of Scientific Research and Technology(ASRT)Egyptian Journal of Soil Science0302-670154420141230Impact of Irrigation Intervals and Fertilization on Actual Evapotranspiration and Wheat Production30531818010.21608/ejss.2014.180ENJournal Article20140205<span style=" mso-bidi-font-family: '';"> FIELD experiments were conducted in clay loam soil during two <span style="color: white;">…. </span>successive seasons 2010/2011 and 2011/2012 at the Agricultural Experimental station, Faculty of Agriculture, Cairo University to investigate the impact of 4 irrigation frequencies combined with three fertilizers as well as control treatment (without fertilizer) on actual evapotranspiration (ETa), grain yield (<em><span style="color: black;">Triticum</span></em><span style="color: black;"> <em>aestivum</em>, L. Sids1</span>) and water use efficiency (WUS) of wheat under furrow irrigation system and Giza region conditions. The results clearly revealed that increasing irrigation frequency significantly decreased seasonal ETa values during studied growing seasons. While the addition of inorganic and organic fertilizers to the studied soil significantly increased seasonal ETa compared to the control treatment (without fertilizers). The wheat crop irrigated by short irrigation interval ≤ 14 days with fertilization by combined between inorganic and organic fertilizers increased seasonal ETa values. While the wheat crop irrigated by the long irrigation interval of 18 days with separately organic fertilizer decreased seasonal ETa value. The results revealed that irrigation interval every 10 days with combined fertilizers treatment had the highest seasonal ETa value (44.56 cm) while the irrigation interval every 18 days with separately organic fertilizer had the lowest seasonal ETa value (37.79 cm) compared to the control treatment (without fertilizers) during studied growing seasons. The results noticed that </span><span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;">the effect of </span><span style=" mso-bidi-font-family: '';">irrigation frequencies significantly influenced the grain yield for studied growing seasons. Wheat grain yield values increased by increasing irrigation interval from 10 to 14 days. However, the increasing irrigation interval to 18 days decreased wheat grain yield. The wheat grain yield values significantly increased by the addition of combined inorganic and organic fertilizers to the studied soil compared with the control treatment (without fertilizers) during studied growing seasons. The wheat crop irrigated by the short irrigation interval of 14 days with fertilization by combined between inorganic and organic fertilizers increased grain yield values, while, irrigated by the long irrigation interval more than 14 days with separately organic fertilizer decreased grain yield values. Generally, the results showed that increasing irrigation frequency significantly decreased the water use efficiency values of the wheat crop during studied growing seasons. The addition of inorganic and organic fertilizers to the studied soil significantly increased wheat WUS compared to the control treatment (without fertilizers). The interaction between irrigation frequencies and fertilizers types on water use efficiency values of the wheat crop was no significant effect. The wheat crop irrigated by </span><span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;">short </span><span style=" mso-bidi-font-family: '';">irrigation interval of 14 days with fertilization by combined between inorganic and organic fertilizers increased wheat WUS values, while, irrigated by the long irrigation interval of 18 days with separately organic fertilizer decreased WUS values. Consequently, under furrow irrigation system and Giza region conditions, the irrigation interval of wheat plants must be a short interval of 14 days with fertilization by combined between inorganic and organic fertilizers in clay loam soil.</span>The National Information and Documentation Centre (NIDOC) affiliated to Academy of Scientific Research and Technology(ASRT)Egyptian Journal of Soil Science0302-670154420141230Effect of Silicon and Saline Irrigation Water on Productivity of Two Wheat Cultivars at South Sinai, Egypt31933618110.21608/ejss.2014.181ENJournal Article20140219TWO <span style=" mso-bidi-font-family: '';">field experiments were conducted at Ras-Sudr Research <span style="color: white;">……</span> Station, South Sinai Governorate during two successive seasons, 2011/2012 and 2012/2013, to study the effect of three levels of silicon as KAlSi<sub>3</sub>O<sub>8</sub> incorporated into the soil at (100, 200 and 300 kg/ fed) <span style="letter-spacing: -.2pt;">compared to control (without silicon) on two wheat cultivars Sakha 94</span> (salt-tolerant) and Gimeza 10,( salt-sensitive). Both cultivars were irrigated from two wells different in salinity levels </span><span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;">(4236 </span><span style=" mso-bidi-font-family: '';">and 4748 ppm, moderate level) and (7001 and 7360 ppm high level) in the first and second seasons, respectively.</span>
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<span style=" mso-bidi-font-family: '';">Obtained results showed that increasing irrigation water salinity from (4236 up to 7001 ppm) in the first season and from (4748 to 7360 ppm) in the second season, decreased the grain yield and its components in Sakha 94 and Gimeza 10. Gimeza 10 was superior to Sakha 94 in all yield criteria in the two growing seasons except protein yield was superior in Sakha 94. The highest level of silicon (300 kg KAlSi<sub>3</sub>O<sub>8</sub> /fed) had the superiority effect in decreasing the soil salinity hazard and consequently increased significantly all yield criteria of the two cultivars. </span>
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<span style=" mso-bidi-font-family: '';">The effect of second order interaction indicated that incorporated soil by silicon (300 kg/fed) planted with Gimeza 10 which irrigated by (4236 and 4748 ppm) produced the highest grain yield and yield components in both seasons. However, the highest protein yield has resulted in Gimeza 10 treated with silicon (300 kg/fed). Grain yield was significantly improved in Gimeza 10, than Sakha 94, with the application of silicon (300 kg/fed). </span>
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<span style=" mso-bidi-font-family: '';">Potassium content was significantly increased in grain wheat cultivars due to soil application of silicon under saline soil conditions. Sodium content was higher in grain wheat, cv. Sakha, 94, under saline soil condition; however Si application significantly reduced Na content in grain, while it significantly increased in K: Na ratio. </span><span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;">High K and low Na contents in grain wheat cultivars may be one of the possible mechanisms of increasing salinity tolerance by silicon application.</span>
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<span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;">In general, the current research suggested that Si application not only increased the quantity but also enhanced the quality of wheat cultivars grown under salt stress conditions. Therefore, silicon at the rate of 300kg/fed and Gimeza 10, which irrigated with a moderate level of salinity (4236 ppm) encourage the farmers to use of silicon to give promising grain yield.</span>The National Information and Documentation Centre (NIDOC) affiliated to Academy of Scientific Research and Technology(ASRT)Egyptian Journal of Soil Science0302-670154420141230WET Sensor Technique to Evaluate Soil Moisture Distribution Patterns under Different Discharge Rates33735418210.21608/ejss.2014.182ENJournal Article20140219<span style=" mso-bidi-font-family: ''; color: black; mso-bidi-language: AR-EG;"> <span style="letter-spacing: -.3pt;">INSURANCE precise placement of water and fertilizer in active</span> root </span><span style=" mso-bidi-font-family: ''; color: white; mso-bidi-language: AR-EG;">…….</span><span style=" mso-bidi-font-family: ''; color: black; mso-bidi-language: AR-EG;">zone is based on suitable moisture distribution pattern under point source emitter, consequently, is affected by some soil properties and emitter discharge rate. This investigation aims to evaluate the patterns of soil moisture distribution under different discharge rates for two different soils (sandy and loamy). The studied discharge rates were 1.8, 4.6 and 8 L h<sup>-1</sup>, in addition to flooding application for comparison. The study also aims to detect the reliability of applying equivalent water depth equation, particularly when water is trickling. For all treatments, soil moisture was measured using a moisture meter called "WET sensor" which calibrated in Lab. for both soils before field work. Validation of Schwartzman and Zur’s model as a simplified semi-empirical method to determine the geometry of wetted soil volume was to detect both studied soils as an additional objective. </span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; mso-ansi-language: EN;" lang="EN">The obtained results </span></span><span class="hps"><span style=" mso-bidi-font-family: ''; mso-ansi-language: EN;" lang="EN">showed </span></span><span style=" mso-bidi-font-family: '';">a high correlation <span>between sensor reading and oven-dried value, introduced high R<sup>2</sup> values equaled 0.999 and 0.9804 for sandy and loamy soil, respectively. </span></span><span class="hps"><span style=" mso-bidi-font-family: ''; letter-spacing: -.1pt; mso-ansi-language: EN;" lang="EN">Based on the designed wetted soil volume, results showed that the best moisture distribution was recorded<span style="color: black;"> under 4.6 L h<sup>-1</sup> and flooding treatment for sandy soil while recorded under 1.8</span></span></span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; mso-ansi-language: EN;" lang="EN"> and 4.6 L h<sup>-1 </sup>rates for loamy soil. </span></span><span style=" mso-bidi-font-family: ''; color: black;">Generally, the application rate of 4.6 L h<sup>-1</sup> could achieve the desired moisture distribution in both soils, therefore, this trickling rate should be selected in such soils than the other. </span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; mso-ansi-language: EN;" lang="EN">Applying of equivalent water depth equation showed that desired progression of wetting</span></span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; mso-ansi-language: EN;" lang="EN">front</span></span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; mso-ansi-language: EN;" lang="EN">appeared to be closely </span></span><span class="longtext"><span style=" mso-bidi-font-family: ''; color: black; mso-ansi-language: EN;" lang="EN">achieved </span></span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; mso-ansi-language: EN;" lang="EN">under flooding treatment in sandy soilthan in </span></span><span style=" mso-bidi-font-family: ''; color: black;">loamy</span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; mso-ansi-language: EN;" lang="EN">. So, flooding irrigation could be successfully applied </span></span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; mso-ansi-language: EN;" lang="EN">sandy soil with rationally water amounts. </span></span><span style="font-size: 9pt; color: black;" lang="EN">Therefore, from the view point of wastewater, nutrients loss and soil contamination, flooding could be more safety<span class="hps"> <span>compared to the other treatments. </span></span></span><span style="font-size: 9pt; color: black; letter-spacing: -0.1pt;">On the other hand, applying the same equation for loamy soil could only be achieved by 87 % and 67 % of the desired moisture for a given depth under 8.0 L h<sup>-1</sup> and flooding treatments, respectively. <span class="hps">So, 8.0 L h<sup>-1</sup> and flooding treatments are not recommended for </span></span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; letter-spacing: -.1pt; mso-ansi-language: EN;" lang="EN">such soil. Regarding </span></span><span style="font-size: 9pt; color: black; letter-spacing: -0.1pt;">both irrigation scheduling and design, the statistical analysis indicated that the most suitable wetted depth and width could be obtained under 4.6 </span><span style="font-size: 9pt; color: black; letter-spacing: -0.1pt;">L h<sup>-1</sup> for sandy soil and under 1.8 and 4.6 L h<sup>-1</sup> for loamy </span><span style="font-size: 9pt; letter-spacing: -0.1pt;">soil, therefore, an economic emitters distance and reduction of salt accumulation around the plant could be achieved<span style="color: black;">. </span></span><span style="font-size: 9pt; color: black; letter-spacing: -0.1pt;">According to soil hydraulic conductivity, wetted width to witted depth ratio could be used as a decision support aid to determine the emitter distance and numbers, consequently, avoid wastewater and cost. </span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; letter-spacing: -.1pt; mso-ansi-language: EN;" lang="EN">Considering the difficult in measuring both laterally and vertically water movement, </span></span><span style="font-size: 9pt; color: black; letter-spacing: -0.1pt;">obtained results showed a good agreement between simulated of </span><span class="hps"><span style=" mso-bidi-font-family: ''; color: black; letter-spacing: -.1pt; mso-ansi-language: EN;" lang="EN">Schwartzman-Zur's model</span></span><span style="font-size: 9pt; color: black; letter-spacing: -0.1pt;"> and field observations particularly for the </span><span style="font-size: 9pt; color: black; letter-spacing: -0.1pt;">loamy</span><span style="font-size: 9pt; color: black; letter-spacing: -0.1pt;"> soil than sandy</span><span style="font-size: 9pt; color: black; letter-spacing: -0.1pt;">.</span>The National Information and Documentation Centre (NIDOC) affiliated to Academy of Scientific Research and Technology(ASRT)Egyptian Journal of Soil Science0302-670154420141230Impact of Irrigation Management on Shallow Groundwater Fluctuation and Soil Salinity: The Saltmed Model35537118310.21608/ejss.2014.183ENJournal Article20140406<span style=" mso-bidi-font-family: ''; color: black;">IN SIWA OASIS, situated in Egypt, secondary salinization of irrigated lands is a crucial problem. The results found that the Siwa shallow groundwater (</span><span style=" mso-bidi-font-family: ''; mso-bidi-language: AR-EG;">SGW) and <span style="color: black;">high summer evapotranspiration</span> is considered the main cause of soil salinization, however, the irrigation water sodicity is considered the main causes of soil sodicity. The SGW depth generally decreased in winter and increased in summer seasons. A high correlation was found between the soil EC (dS m<sup>-1</sup>) and soil SAR and Cl (meq L<sup>-1</sup>) (R<sup>2</sup> = 0.89 and 0.91 for SAR and Cl, respectively), consequently, the dominant ions in Siwa soil solution are Na and Cl. The results also emphasise good correlation between soil available nitrogen and SGW contamination with nitrate (r<sup>2</sup> = 0.80 and 0.73, winter and summer, respectively). The eutrophication is expected in the study area especially in winter seasons due to nitrate concentrations increase. </span><span style=" mso-bidi-font-family: ''; color: black;">A conceptual, daily, semi-distributed hydrologic Saltmed model </span><span style=" mso-bidi-font-family: ''; color: black; mso-bidi-language: AR-EG;">was found to be successful under Siwa climatic conditions. The model recorded that the quantity of irrigation water used in traditional irrigation is more than requirement. The traditional irrigation applies 300 L/m<sup>2</sup>/14 days, however, the quantity of 50 L/m<sup>2</sup>/14 days is adequate for olive crop water requirement and soil salinity removal. The results of this research could be applicable to similar situations worldwide.</span>The National Information and Documentation Centre (NIDOC) affiliated to Academy of Scientific Research and Technology(ASRT)Egyptian Journal of Soil Science0302-670154420141230Acid-Base Properties of Humic Acids Isolated from Different Sources37338618410.21608/ejss.2014.184ENJournal Article20140406<span style=" mso-bidi-font-family: '';"> POTENTIOMETRIC titration was used for obtaining detailed <span style="color: white;">……</span><span>information on the acid-base properties of humic acids. The studied humic acids were isolated from different four sources, <em>i.e</em>., alluvial soil (HAs), farmyard manure (HAf), compost (HAc) and poudrette (HAp). The isolated humic acids were purified and performed. Back titration using 0.1M HCl as the titrant and direct titration using 0.1M NaOH as the titrant of humic acid solutions (2 mg/ml)</span> at the ionic strength of 0.1 were executed. Moreover, total acidity and functional groups of humic acids were estimated. </span>
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<span style=" mso-bidi-font-family: '';">The studied humic acids were similar in their acid-base properties: i) the data of direct and back titration curves which limited the position and composition of dissociation or ionization of functional groups of the studied humic acids were more similar, ii) total functional groups of HA determined from back and direct potentiometric titration was ranged between 5.40-6.54 and 4.20-5.00 mmolc/g HA, respectively, iii) total functional groups of humic acids determined using potentiometric titration were varied from those determined using normal titration methods, where total functional groups at normal titration methods ranged between 11.32 and 19.58 mmolc/g HA and iv) humic acid extracted from poudrette has the highest value of total acidity followed by compost, farmyard manure, while the soil came late.</span>The National Information and Documentation Centre (NIDOC) affiliated to Academy of Scientific Research and Technology(ASRT)Egyptian Journal of Soil Science0302-670154420141230Adsorption Behavior of Lead, Cadmium and Nickel on some Calcareous Soils38740018510.21608/ejss.2014.185ENJournal Article20140409<span style=" mso-bidi-font-family: ''; mso-bidi-font-weight: bold;"> THERE are many environmental factors that influence the mobility <span style="color: white;">….</span> and bioavailability behavior of some heavy metals in soils. One of these factors is the content and form of calcium carbonate in soils.</span>
<span style=" mso-bidi-font-family: ''; mso-bidi-font-weight: bold;">Experimental work has been carried out applying 1 and 3 mmole (mM) of Pb, Cd and Ni (in chloride forms) on 5 different calcareous soils from the north coast area, Egypt. The adsorption of these elements at interval times from 1 to 168 hours was measured. Four kinetic models were applied: Elovich, Modified Frendlich, Horels and Diffusion equation.</span>
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<span style=" mso-bidi-font-family: ''; mso-bidi-font-weight: bold;">The obtained results indicate that the adsorption process takes three stages, a rapid rate from the starting time to about 2 hr, intermediate stage until about 100 hours and slow or steady rate until the end of the reaction (168 hr). Comparing the adsorption process through the five soil samples can be arranged as follows; S<sub>5</sub>>S<sub>3</sub>>S<sub>4</sub>>S<sub>2</sub>>S<sub>1</sub>. The retention of heavy metals depends on the amount of active calcium carbonate, clay content and surface area of the soil. The values of adsorbed three heavy metals on the five soil samples can be arranged as; Cd > Pb >Ni.</span>
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<span style=" mso-bidi-font-family: ''; mso-bidi-font-weight: bold;">The constants of the four kinetic equations (a, b and r<sup>2</sup>) were compared for the two concentrations of each metal (Elovich, Modified Frendlich Equation "MFE", Horels and Diffusion). The correlation coefficient between soil criteria and the constants of the applied kinetic models reveals that highly positive correlation between active calcium carbonate, surface area and clay content with a and b constants in Elovich and Diffusion equations.</span>