This research was conducted by a subsoiler (double tines ) plow of mounted type to study its effect on the mechanical and physical soil properties (soil bulk density, soil penetration resistance and soil cohesion ) . The experiments using four depth (25,35,45and 55 cm ) in eultiuoted and uneultiuoted silty clay soils . The results showed that the subsoiler plow reduced the soil bulk density ,soil penetration resistance and soil cohesion by 25% ,78% and 82% respectively . The subsoiler had greater effection the three soil properties as the plowing depth increased especially at plowing depth of 50 cm .

تضمن البحث استخدام محراث تحت التربة ثنائي الأسلحة المعلق على جرار ماسي فركسن لمعرفة تأثير المحراث على بعض الخواص الفيزيائية و الميكانيكية والتي شملت الكثافة الظاهرية ومقاومة التربة للاختراق و قوة التماسك في التربة .

Subsoiler hardpan bulk density penetration resistance cohesion

Afield experiment was conducted in silty clay soil classified as fine loamy active calcareous hyperthermic Typic Torrifluvents. The soil was planted by Alfalfa crop viriety (Medicago sativa) in the season of 2008-2009.Two irrigation water types were used, namely ; treated water by care – free water conditioners equipment and untreated water ( shatt –Al arab river water) it Ec was 7.94 ds.m-1. care – free equipment was connected in the irrigation pass line of the shatt – Alarab river water ; The diameter of the equipment was 1.5 in ( 3.81 cm).The soil properties changes due to using care- free equipment was studied after one and two months. The studied soil physical properties are saturated hydraulic conductivity , bulk density , total porosity and moisture content and its relation with sodium adsorption ratio ( SAR) for depths of 0-25 , 25-50 and 50-75 cm.The results showed that the treated water increased the saturated hydraulic conductivity and soil total porosity and decreased SAR significantly by 50.72 , 1.22 and 20.64%,respectively, compared with saline soil ( untreated water). But the treated water did not effect significantly on the soil bulk density and moisture content values.The Saturated hydraulic conductivity value is 0.994 m. day-1 after one month but became to 0.396 m. day-1 at the end of the experiment.The bulk density decreased while the total soil porosity increased significanthy by 4.9 and 5.33% , but they increased to 8.71 and 9.75% after two months compared with original values respectively. At the end of the experiment , SAR inereased significantly by 123.98% compared with its value of after one month of installing the equipment. The time period had no effect significant on the soil moisture content.The results also showed that the soil bulk density and the moisture content increased by 4.09 and 20.00% respectively while SAR decreased by 13% for depth of 50-75 cm compared with depth 0-25 cm.The saturated hydraulic conductivity and total soil porosity was not affected significantly with soil depth

نفذت تجربة حقلية في تربة ذات نسجة طينية غرينية (silty clay) مصنفة الى Fine loamy active calcareous hyperthermic Typic Torrifluvents زرعت بمحصول الجت صنف(Medicago sativa) للموسم الزراعي 2008-2009 تضمنت التجربة نوعين من مياه الري : مياه معالجة ومكيفة الخواص باستخدام جهاز water conditioners care- free ومياه شط العرب المالحة ذات الايصالية الكهربائية 7.94 ديسيسيمنز.م-1 تم نصب مكيف خواص المياه (care – free ) ذو القطر ( 1.5) انج على خط الري لمياه شط العرب المالحة وبشكل جانبي . حددت فترتين زمنية وهي شهر وشهرين من نصب الجهاز لدراسة التغيرات في خصائص التربة الفيزيائية والمتمثلة بالايصالية المائية المشبعة ، الكثافة الظاهرية ، المسامية الكلية والمحتوى الرطوبي وعلاقتها بنسبة امتزاز الصوديوم ( SAR) وللأعماق ( 0-25) ، ( 25-50) و( 50-75) سم.أظهرت النتائج ان المياه المعالجة والمكيفة الخواص أثرت معنويا في زيادة قيم الايصالية المائية المشبعة والمسامية الكلية للتربة مع انخفاض في نسبة امتزاز الصوديوم وبنسبة 50.72 ، 1.22 و 20.67% على التوالي مقارنة بالمياه المالحة غير المعالجة . ومن ناحية اخرى لم تؤثر المياه المعالجة معنوياً في قيم الكثافة الظاهرية والمحتوى الرطوبي للتربة.أوضحت النتائج ارتفاع قيمة الايصالية المائية المشبعة للتربة الى 0.994 م. يوم -1بعد مرور شهر من نصب الجهاز في حين انخفضت في نهاية التجربة الى 0.396 م. يوم-1 . ومن جهة اخرى انخفضت قيم الكثافة الظاهرية وارتفعت قيم المسامية الكلية معنوياً بعد مرور شهر وبنسب 4.9 و 5.33% وازدادت النسبة بعد مرور شهرين الى 8.71 و 9.75% مقارنة بقيمتها الاولية لكلا الصفتين وعلى التوالي . وفي نهاية التجربة ازدادت قيمة الـ SAR معنوياً وبنسبة 123.98% مقارنة بقيمتها بعد مرور شهر من نصب الجهاز . ولم يكن للفترة الزمنية أي تأثير معنوي في قيم المحتوى الرطوبي للتربة . بينت النتائج زيادة الكثافة الظاهرية والمحتوى الرطوبي مع انخفاض قيمة SAR للعمق( 50-75) سم وبنسب 4.09 ، 20.00 و 3.13% مقارنة بالعمق ( 0-25)سم وعلى التوالي ، بينما لم تتأثر قيم الايصالية المائية المشبعة والمسامية الكلية معنوياً مع زيادة عمق التربة .كلمات دالة : تكييف خواص الماء ، الايصالية المائية المشبعة ، الكثافة الظاهرية ، الرطوبة ، SAR .

care – free --- saturated hydraulic conductivity --- Bulk density --- moisture --- SAR

this research was conducted through three stations affected by different degrees of desertification. for the period Nov., 2007 to Sep.,2008, The aim of this research was to develop simple and accurate method for assessment the status of desertification in arid zone of lower Mesopotamian plain , to develop simple and accurate method for assessment the status of desertification in arid zone of lower Mesopotamian plain , including monthly measurements of dry aggregate stability (AS) expressing by geometric mean diameter (GMD) and weight mean diameter (MWD), The results showed the light desertified was significantly superior with values of geometric mean diameter (GMD) equal to (0.779)mm. The highest value of geometric mean diameter (0.802) mm was found in February, while the lowest values of geometric mean diameter was found in July (0.500) mm . Similarly, the weight mean diameter was significant difference among these sites . The geometric mean diameter was positively correlated with Organic matter content (0.84), weight mean diameter (0.95), total porosity (0.97), Dry Aggregate of Soil greater than 1mm (0.79) and soil moisture (0.89) ,whereas the geometric mean diameter was negatively correlated with dry bulk density (─ 0.89) and rate of soil loss (─ 0.78). In generally, The results showed the effect of soil structure on different degrees of desertification is more related of (GMD) than (MWD),

أجريت الدراسة في ثلاثة مواقع متأثرة بالتصحر بدرجات مختلفة (تربة زراعية ، تربة متأثرة بالتعرية الريحية ، وتربة تنتشر فوقها الكثبان الرملية ) تقع ضمن منطقة البطحاء في محافظة ذي قار، خلال المدة من شهر تشرين الثاني 2007 ولغاية شهر أيلول 2008. لغرض تطوير طريقة مبسطة ودقيقة لتقييم حالة التصحر في منطقة السهل الرسوبي الأسفل في جنوب العراق من خلال القياسات الشهرية لثباتية تجمعات التربة الجافة Aggregate Stability (AS) المعبر عنها بدلالة كل من معدل القطر الهندسي Geometric Mean Diameter (GMD) ومعدل القطر الموزون ((MWD Mean Weight Diameter . بينت النتائج تفوق للتربة خفيفة التصحر بتسجيلها أعلى متوسط سنوي بلغ 0.799 ملم مع تسجيلها لأقصى متوسط شهري خلال شهر شباط بلغ 0.802 ملم بالقابل سجل شهر تموز أدنى متوسط شهري بلغ 0.500 ملم .كما بينت النتائج وجود اختلافات معنوية في ثباتية التجمعات الجافة المحسوبة على أساس معدل القطر الموزون بين المواقع الثلاثة وبطريقة مماثلة لمعدل القطر الهندسي .وأظهرت دراسة عامل الارتباط وجود علاقة معنوية ايجابية لمعدل القطر الهندسي مع كل من محتوى المادة العضوية(0.84) ومعدل القطر الموزون (0.95) وتجمعات التربة الجافة الأكبر من واحد مليمتر(0.79) ورطوبة التربة (0.89) ، في حين كان هنالك ارتباط معنوي سالب مع كل من الكثافة الظاهرية (─ 0.89)ومعدل التربة المفقودة بالتعرية(─ 0.78) .وبينت النتائج بشكل عام إن هنالك أفضلية في استعمال معدل القطر الهندسي بالمقارنة مع معدل القطر الموزون لبيان تأثير بناء التربة على درجات التصحر المختلفة .

desertification --- Dry Aggregate of Soil --- dry bulk density --- التصحر --- التعرية الريحية --- ثباتية التجمعات الجافة

A field experiment was carried out in silty loam soil at Agricultural research station, College of Agriculture during the corn growing season of 2015. The aim of study was to determine the effect of manure (cattle residues) levels (0, 20 and 40 ton ha-1), the depth of manure application (10, 20 and 30 cm), and the method of manure application (mixing with soil and subsoil laying) on soil bulk density and soil water content. The manure was added at certain treatments by using a ditch opener and manure laying machine which was designed and manufactured in the Agriculture Machines and Equipment Department, College of Agriculture, University of Basrah in 2015. The field was plowed perpendicularly, and the treatments were arranged in RCBD with split-split plot design with three replicated using drip irrigation system. Corn (Zea mays L.) seeds were planted on the manure rows. All plots received NPK fertilization with the same levels. At the end of growing season, soil samples (0-30 cm) were collected to examine soil bulk density and soil water content. The results showed that, lower bulk density and higher water content were obtained at level of 40 ton ha-1 compared with the levels of 0 and 20 ton ha-1. The soil bulk density decreased from 1.23 to 1.20 Mg m-3 and the soil water content increased from 26.33 to 30.23 % when the depth of application increased from 10 to 30 cm. Mixing manure with soil resulted in lower value of bulk density and higher value of water content compared with subsoil laying method. Mixing manure with soil down to the depth of 30 cm amount of 40 ton ha-1 improved the soil bulk density which reached lower value of 1.14 Mg m-3 and soil water content increased to 36.19% among all other treatments.

organic fertilizer machine --- organic residues --- soil bulk density --- soil water content.

In this study, different percentages (2, 4, 6, 8, and 10% by weight of the soil) of chopped polymeric (plastic bottles with maximum particle size 2.36 mm and 1.18 mm in addition to rubber tires of 0.6 mm max particle size) wastes are incorporated with soil to produce lightweight clay bricks, to find the optimum percentage satisfying the requirements of bricks grade C using for non-structural walls (partitions).The effects of different types and percentages of the polymeric wastes on firing shrinkage, density, water absorption, compressive strength and thermal conductivity of the fired bricks were studied. Results indicate that it is possible to incorporate not more than 8% of chopped rubber tires or not more than 6% of chopped bottles to the clay soil to produce lightweight fired clay bricks satisfying the compressive strength and water absorption requirements for grade C of bricks (used for partitions) according to the Iraqi specification IQS 25/1988, in addition to reducing the thermal conductivity by 13-17% which is desirable as it will reduce the energy required for heating and cooling. Also, found that the size of the incorporated particles of plastic wastes in clay, used for bricks manufacturing, did not have a significant effect on the different studied properties of bricks. In addition to, the incorporation of chopped rubber tires, having smaller particles size and more sphere particles shape, produce fired clay bricks with more homogeneous pores distribution and smaller size compared with clay brick incorporating chopped plastic wastes having flaky shape and larger particles size, leading to produce clay brick with higher density and strength, with lower water absorption. As a total results, the incorporation different types of polymeric wastes (chopped plastic bottles with 2.36 and 1.18 max size and chopped rubber tires) with percentages (2, 4, 6, 8, and 10% by weight of soil) , cause the firing shrinkage and water absorption to increase by (0.6-20.2%) and (3-43.5%) respectively, while the density, compressive strength, and thermal conductivity decrease by (3.5-25.1%), (0.4-2.3%), and (2.1-31.9%) respectively with respect to the reference fired clay bricks, depending on the percentage, particles size, and type of the polymeric wastes addition.

brick --- bulk density --- compressive strength --- firing shrinkage --- plastic wastes --- rubber tires wastes --- thermal conductivity.