A laboratory experiment was carried out in the Clay Minerals and Colloids Laboratory in the Department of Soil Sciences and Land Reclamation at the Faculty of Agricultural Engineering - University of Aleppo. The research aims to know the effect of tw
o types of salts (NaCl - Na2SO4) with five concentrations of each of the salts studied in the laboratory experiment on the stability of artificial soil aggregates and to know the salt concentrations that cause the greatest damage in the destruction of artificial soil aggregates. The results indicated the effect of the increased concentration of salts in increasing the percentage of aggregates that were subjected to collapse. The study also indicated that soil aggregates were damaged more by sodium chloride salt compared to sodium sulfate salt. The results indicated that sodium chloride salt contributes to the destruction of soil aggregates, especially at a concentration of 10 g.𝓁-1, where the percentage of destroyed aggregates reached about 35%. Sodium sulfate salt also contributed to the destruction of soil aggregates, and the highest value for the percentage of destroyed aggregates was (25.1%) at a concentration of 8 g.𝓁-1.
التحليل الحبيبي للتربة:
تتراوح احجام دقائق التربة من احجام كبيرة يتجاوز قطرها 300 مم تدعى جلمود بموجب النظام الموحد لتصنيف التربة او لغاية حجم صغير جدا لا يتجاوز قطره 2 للأس -10 مم او 2 انكستروم.
ان الطريقتين الشائعتين لقياس حجم التربة هما:
1- الت
حليل الخشن بالمناخل للترب خشنة الحبات
2- طريقة المقياس المائي للترب ناعمة الحبات (اختبار هيدروميتر)
تحتوي هذه المحاضرة تفاصيل عن طريقة اجراء التحليلين وقواعد اختبار هيدروميتر
This study was conducted in Lattakia Governorate (Burj Islam Village) to study the level of contamination of the greenhouses soil with the two organic phosphorous pesticides Dimethoate and Dichlorovos. The optimal wavelength was determined for the an
alysis of both pesticides using High Performance Liquid Chromatography (HPLC) technology with UV/DAD detector. According to the results, the optimal wavelength for the analysis of Dimethoate is 200 nm, while it was 195 nm for the analysis of Dichlorovos. The recovery of Dimethoate was estimated at wavelength 200 nm which was 101.33 ± 3.868 and for dichlorvos at wavelength 195 nm when it was 98.995 ± 2.078. The results also showed that the greenhouses soil were contaminated with the residues of both pesticides, Dimethoate was detected in concentrations between (0.839 - 2.668) ppm, while Dichlorovos concentrations were between (10.046 - 44.359) ppm, indicating extensive use of both especially Dichlorovos, whose concentrations were higher than Dimethoate's in the studied sites.
The aim of this research is to predict the quantities of soil lost by the water erosion in the
Al-Hawiz Dam basin area using GIS and RUSL. R factor was calculated through
matimatical equation after collecting rain data during 2008-2017 from weather
station at
Basel-Al-Assad airport .k value of each soil sampl was calculated after determination of
txture,structure,saturated hydrolic conductivity, and organic matter).a map were prepared
showed local distribution of k values .slop factor was determined as well as using DEM for
studied region, and slop map was introduced in mathematical equation through a GIS to
obtain LS map .NDV used for studied region to calculate C map.To obtain predictive map
of soil lost quantitis ,maps of LS,C,K was multiplicated with R value.
The results showed that R value in studied region 342.78 ,while k factor value was
0.7-0.28.soil with low value concentrated at medium part of studied region,whil slop
factor value was between 0 and 38.87.C factor value was 0.29 at west part and 0.98 at east
part .prediction map of lost quantites was classified in to 4 degrees according erosion risk (
very low risk ,low,medium,high .The results of soil lost quantities were classified in to 4
classes in studied region : very low( 0-5) t/h/year,low( 5-12 ) t/h/year and medium ( 12-24
t/h/year and severe in which soil loss exceeded 24 t/h/year
The research was performed by isolating some species of soil- fungi from agricultural soils
handling with different pesticides and fungicides. Where the following fungi were isolated:
Aspergillus niger (The isolates A1 and A2), Fusarium oxysporum (
The isolate F),
Trichoderma harzianum (The isolate T). Also F. solani (The isolate F7) and T. viride (The
isolate T.v) were used, whereas they were taken from high studies laboratory- Science
Faculty- Tishreen University at a previous search.
The research was conducted to assay the ability of the previous fungi to degradation a
number of pesticides, the insecticide "Dolan", the insecticide "Plantocide", the nematicide
"Vydate" and the fungicide "Bayfidan", through the effect of double dose of each
pesticides in the biomass of the studied fungi on PDB medium. In addition to analysis the
results residues of pesticides using Spectrophotometer, and evaluation the pH values.
In present investigation attempt has been made to study the bearing capacity and settlement
characteristics of footings subjected to central vertical load and resting on layered soil with
the help of model tests and with the application of finite e
lement method (FEM) to
calculate bearing capacity of a strip footing on one-layer and two-layer soil (Sand and
Clay). To investigate the effect of various parameters on soil bearing Capacity a
commercial finite element software, PLAXIS, has been used. Soil profile contains two soil
types including sand and clay. Soil behavior is represented by the elasto-plastic Mohrcoulomb
(MC) -model. For a one-layer case, the bearing capacity also is calculated which
has a good agreement with theoretical equations. For a layered soil, soft-over strong soil,
parametric study was carried out. It is concluded that the bearing capacity of footing
decreases as the height of clayey soil increases whilst the displacement under footing
increases. There is a critical depth where the stronger bottom layer does not affect ultimate
bearing capacity and failure mechanism of footing.
This research study aims at investigating the potential benefits of using the reinforcement
to improve the bearing capacity and reduce the settlement of strip footing on clay. To
implement this objective, many numerical 2D-analyses by finite elemen
t method / Plaxis
program were performed to study the behavior of reinforced soil foundation. And then we
carry out a parametric study of the most effective parameter on bearing capacity. The
results showed that the inclusion of reinforcement can significantly improve the bearing
capacity and reduce the footing settlement. The strain developed along the reinforcement is
directly related to the settlement. The results also showed that the inclusion of
reinforcement can redistribute the applied load to a wider area, thus minimizing stress
concentration and achieving a more uniform stress distribution. The redistribution of
stresses below the reinforced zone can result in reducing the settlement of the underlying
weak clayey soil.
يعود ظهور شجرة الزيتون إلى ماض سحيق ( ستة آلاف سنة ) وقد ارتبط نشؤوها بتاريخ بلدان البحر الأبيض المتوسط حيث لعبت منذ الأزمان الأولى دوراً هاماً في اقتصاد شعوب البحر الأبيض المتوسط
He studied the effect of conservative and traditional agriculture on some different soil properties by digging soil sections in five fields belonging to the Agricultural Scientific Research Center in Salamiyah, the General Authority for Scientific Agricultural Research during the 2015 and 2016 seasons.
The experiment carried out to improve the efficiency of drip
irrigation system , based on soil moisture. The indirect measure of
humidity Was used in the experiment, connected with the pointing
device (separator continued), and a control device pr
ogrammed on a
low humidity degree, which is degree the field capacity of the soil and
which value is 25%, and on a high moisture degree which is saturation degree
at 75%..