Before contact with leachate, GCL must be sufficiently hydrated, or in other words absorb moisture, so that it has sealing properties and prevents the penetration of leachate into the subsoil. GCL absorbs moisture from the subsoil and swells and gets sealing properties, therefore, investigating the moisture absorption behavior of GCL from the subsoil has become important and has become the subject of research by some researchers. The purpose of this research is to investigate the moisture absorption behavior of GCL from the subsoil contaminated with leachate and what effect the presence of leachate has on the hydration of GCL and its sealing properties. In this research, the moisture absorption behavior of GCL from three types of sandy soil, mixed and fine-grained, for each of these soils in three different initial moisture percentages, for sandy soil including 8%, 13%, and 23%, for mixed soil and Fine-grained soil including 2.4%, 12.4% and 17.4% was investigated and its results were presented, then the moisture absorption behavior of GCL in the presence of leachate was investigated for all three types of soil in the condition that the soils were in three types of leachate percentage. Various were contaminated. The results of investigating the moisture absorption behavior of GCL show that in the presence of leachate, the amount of moisture absorbed by GCL in the tested time period is less than the expected value and the presence of leachate has a significant negative effect on GCL hydration by more than 2 to 6 times.

The problem of steady state seepage from a lined canal towards asymmetrical drainages has been solved using finite element method, analyzing the effect of stratification of subsoil and canal lining on canal seepage discharge and groundwater free surface between canal and drainages. The computations of this model are performed by a computer code in Fortran 77, developed by the author. In case of stratification with two layers, the canal seepage increases with increasing k2/k1. The effect of increasing k2/k1 on canal seepage is more for k2/k1>1, L1/h1=L2/h1>100, large drainage bed widths and smaller thickness of upper layer. In case of stratification with three layers, the effect of the permeability of the third layer on canal seepage and the free surface profile is maximum when k2/k1=1 and reduces when k2/k1 gets away from 1. Effectiveness of lining in reducing seepage is less when drainage distance is large. The model shows that the decrease in canal seepage due to decrease in lining permeability is relatively more significant when the ratio of lining permeability and subsoil permeability ranges in the region from 2×10-2 to 10-3 The decrease in canal seepage is very steep with initial increase in the lining thickness. However, with farther increase in the lining thickness the decrease in canal seepage is not very significant. Therefore, an effective lining permeability can range between1/50 and 1/1000 of the subsoil permeability and its thickness can be kept less than 0.2 differences between elevation of canal water level and drainage water level.

This study was conducted to evaluate the soil physical quality (SPQ) indices of topsoil and subsoil of wheat and sunflower fields in Urmia plain. Principal component analysis (PCA) was used to distinguish the effect of soil layer and cultivation type on SPQ. Soil samplings and measurements were done in two layers (topsoil and subsoil) of 30 agricultural fields (15 wheat fields and 15 sunflower fields). Soil water retention and penetration resistance curves of undisturbed samples were determined using sand box and pressure plate, and micro-penetrometer, respectively. Then, least limiting water range (LLWR), integral water capacity (IWC), and Dexter’ s index of soil physical quality (Svalue) were calculated. There were significant differences (P<0. 05) in the mean values of physical quality indices between the topsoil and subsoil. The relative bulk density (RBD) values of subsoil were bigger than topsoil. Also, the IWC, LLWR, and S values of subsoil were much smaller than those of topsoil, indicating poor physical quality of subsoil layer in the studied fields. This might be related to conventional tillage with heavy machinery, especially under high soil moisture conditions in last decades, which induced some compaction effects in the subsoil. These findings recommend improving of tillage systems and continuous monitoring of cultivation effects on SPQ in the studied area. Evaluating the SPQ indices of wheat and sunflower fields, using the means comparison and PCA, showed that wheat fields had better soil physical quality compared to sunflower fields. The difference of root systems and more human trafficking in the sunflower fields could be the main reasons of lower soil physical quality in sunflower cultivation compared to wheat cultivation.

Background and Objective: Due to the shortage of freshwater for irrigation, wastewater has been used in agricultural irrigation as an important supplement and alternative water resources in recent decades. Irrigation of fields with wastewater can cause potential contamination with heavy metals to soil crops and groundwater, therefore pose a threat to human health and food safety. The aim of this research was to evaluate the effect of irrigation with untreated municipal wastewater on the accumulation of cadmium lead (Pb), (Cd), copper (Cu) and Zinc (Zn) in topsoil and subsoil and top soil properties. Method: In the present study in order to collection of topsoil (0-20 cm) and subsoil (0-40 cm) samples from south of the Borujerd city, 13 fields irrigated with untreated wastewater and 7 fields irrigated with well water were selected with same soil texture. Soil samples were analyzed by the standard methods for Pb, Cd, Cu, Zn, pH, electrical conductivity (EC), organic matter (OM). Findings: Findings indicated that untreated wastewater irrigated soil contained higher concentrations of all heavy metals in topsoil (with the exception of Cu) and in subsoil, compared to well water irrigated soil. Trend of depth variations of metals in irrigated soil followed this form: 1-With wastewater: Pb and Cu in subsoil>topsoil; Cd and Zn in topsoil > subsoil and 2-With well water: Pb and Cu in topsoil > subsoil; Cd and Zn in subsoil > topsoil. Discussion and Conclusion: It seems that light soil texture has been resulted to transport of the metals to deeper soil layers. Overall, the concentrations of Pb, Cu, and Zn were lower than the FAO/WHO standards in soil, while Cd higher than this. Thus, in order to ensure food safety and use of wastewater for irrigation, continuous monitoring and pollution control is required. Besides, if treatment of wastewater is done appropriately, accumulation of heavy metals in soils and crops will occur less.

Bearing capacity prediction of shallow strip foundations is one of the most important issues in geotechnical engineering. There are some bearing capacity equations and design charts proposed by researchers for this purpose. Most of the methods are for homogeneous and up to two layered subsoil. Recently, predicting bearing capacity of shallow foundations on multi layered soils have been interested. In this study, an artificial neural network is developed for bearing capacity prediction of shallow strip foundation based on cohesive multi layered subsoil. Training process of ANN needs a wide range of input data. In this study, a FEM is used for generating data for ANN. ANN has been trained for both kind of layered subsoil. Finally a multiple regression analysis which can generate a relationship between input parameters and target data is defined. Validation of neural network shows that an AAN can predict the ultimate bearing capacity of shallow strip foundation on cohesive layered subsoil with an acceptable accuracy. Effect of each parameter on ultimate bearing capacity of foundation using ANN is investigated. The results are compared with FEM and indicate that an ANN can evaluate the effect of input parameters with an acceptable accuracy. Validation of equations proposed for predicting bearing capacity of shallow foundations using multiple regression analysis indicates that this method can fit our purposes.

Soil pollution by heavy metals is a serious environmental problem that threatens the human health. The present study was carried out to investigate and detect the contamination of heavy metals of arsenic, copper, lead, zinc and iron due to human and natural activities in the sediment of lake bed and the surface soils of the eastern part of Urmia Province, West Azarbaijan Province. A total of 20 soil samples and surface deposition from the depths of 0 to 30 cm were collected randomly from the studied areas. After preparing the samples, extraction was carried out to determine the concentration of the heavy metals in the soil by using hydrochloric acid and nitric acid, and the total concentration of metals was measured using ICP-OES. The results of the calculation of the contamination factor showed that copper, iron, zinc and lead in the class of low and medium pollution and arsenic in 65. 5% of the samples were very high in the class. The high concentrations of copper, lead and zinc contamination in the margin of the city and the contamination of arsenic in the lake bed were observed. The analysis of the contamination factor maps and contamination index with land use and geological map showed that copper, lead and zinc were mostly affected by human activities and arsenic influenced by the maternal materials in the region.

One of the most alive and, to be sure, complicated political and legal events in the Caspian Sea region is the unresolved issue of its legal regime. The Caspian Sea, as a closed sea, has had a volatile history in terms of its legal regime and for the time being one cannot see a clear vision for solving its legal regime problem. The Caspian states have reached a consensus on the issues of environment and territorial as well as the special fishing zone, but the complex Caspian marathon in the exclusive economic zone and also continental shelf of the sea, remains unsolved. In this regard, if we look at the Islamic Republic of Iran’ s position on the legal status of the Caspian Sea, we will see that Iran refers to the "principle of equity" as a basis for the division or delimitation of the Caspian Sea in order to restore its lost rights. This article tries to examine the meaning of the principle of equity as an element of natural justice and to elaborate the practice of the International Court of Justice regarding the delimitation of the continental shelf. We try to reach an accurate understanding of this term and its scope so as to reach a definite idea on the delimitation of the seabed and subsoil of the Caspian Sea.

Soil compaction has become a widespread problem in the world and is one of the factors involved in land degradation and declining crop yields, especially in the arid and semi-arid agriculture. The purpose of this study was to investigate the effects of subsoil compaction on morphological, physiological and agronomic aspects of wheat. The research was carried out in the experimental farms of Anbar Ulum city. The treatments were applied in the form of the completely randomized block design with four independent variables and three replicates. The study treatments included: control treatment (no artificial compression), treatment 2 (two passes of a heavy tractor), treatment 3 (4 times passes of a heavy tractor) and treatment 4 (6 times passes of a heavy tractor. In this study data was analyzed by means of the SAS software package. The type of mean comparison method applied is the LSD test. Results showed that different levels of soil compaction had a significant reducing effect on plant morphological characteristics such as plant height and tiller number. Likewise, soil compaction significantly reduced the agronomic characteristics of wheat like grain weight, biological yield and grain yield, but not so much effect was observed for the harvest index (HI). As for plant physiological characteristics, soil compaction imposed a significant effect such that the concentration of chloride, sodium and potassium concentration in the leaves significantly decreased and so did the leaf area index.

Machine foundations induce a wide range of dynamic shear strains in foundation bed. Dynamic properties of soils including the damping ratio and the dynamic stiffness intensely depend on the level of generated dynamic shear strain. Therefore, considering the appropriate dynamic properties of a foundation bed corresponding to the generated dynamic shear strain is crucial to having a better evaluation of the dynamic response of a machine foundation. This paper presents the design and construction of an apparatus namely “ Foundation Model Response Test (FMRT)” . This apparatus provides the tests to investigate the dynamic properties of machine foundation and underlying bed in a wide range of dynamic shear strains employing a various range of dynamic excitation forces and static weight (dead weight). The FMRT apparatus could be used in the field to evaluate the dynamic response of the undisturbed bed and on the prepared bed in the laboratory test pit. Two types of steady-state and free vibration tests could be conducted by employing the FMRT apparatus. Steady-state vibration tests induce larger shear strain in bed, whereas free vibration tests induce smaller shear strain. Correlation of the results of these two types of tests, dynamic responses, and dynamic properties of foundation bed in a wide range of dynamic shear strain would be achieved. The accuracy and validity of all FMRT tests are possible to monitor precisely and any unwanted noises and modes of vibration are possible to be controlled by evaluating the Fast Fourier Transform (FFT) of all sensors data when conducting tests. Several steady-state and free vibration tests were conducted to illustrate the performance of the designed apparatus. Moreover, the method of calculation, controlling unwanted vibration, and correlation of free and steady-state example tests were submitted. FMRT tests are inexpensive, repeatable, non-destructive and reliable tests that ensure the dynamic response of machine foundation possible accurately.