مجله پژوهش آب ایران
پیاپی 21 (تابستان 1395)

Estimating correct volume of sediment in alluvial rivers play the most crucial role in water and river engineering, water resources, structures, facilities, water and environmental projects. Using the observed records of sediment load is the most reliable way in estimating it. Since userunfriendly measurement tools and its remarkable fluctuation within the river section, sediment sampling is really difficult and needs high experienced professionals. In addition it is costly and time consuming.ý Because of these limitations sediment frequency of observation around the world especially ýin developing and remote areas have decreased. So, researchers considered some modeling ýapproaches based on diverse terrain attributes and þhydrological variables. Some physically-based models such as the unit stream power (USP) theory of Yang, the SHESED model of Wicks and Bathurst are able to universally predict sediment yield of a watershed but their requirements to lots of detailed information such as geological, hydraulic, and hydrological characteristics of the river basin make them difficult and costly. The same situation there is for process-based models such as the modified universal soil loss equation (MUSLE), introduced by Williams, and its family (USLE and RUSLE). So some models based on many simplifying assumptions and empirical relationships, especially for rainfall and runoff erosive effects were employed which in areas with few data would result in high uncertain results. Using of data-driven ýmodels such as different techniques of artificial intelligence are the þalternative method to the previous models. Artificial neural network (ANN) is one of the most þfamous and strong data-driven technique and ýit has been proved to be practical in modeling non-ýlinear systems or complicated hydrologic processes such as sediment transport. Also conventional sediment rating curve (SRC) has been used widely in all over the world. Although these methods might be similar in some aspects, but each of them has its own characteristics that make them differ from the other. So, authors in this study uses combinations of above tools in a new approach and a hybrid model was employed to utilize the quality of each one in estimating the bed load sediment in Yazdakan gauging station simultaneously.
For the present study Yazdakan bridge gauging site (38.476724o, 44.798362o) located on Qatorchay river was considered. ýQatorchayý river in Aras catchment þwith an area ýof 3471.9 km2 is a river ýin West Azerbaijan province of Iran. It arises in the northwest of Zagros Mountain range in Turkey. The total length of Qatorchayý main streams in Turkey before entering to Iran reaches to 115 kilometers.ý From the border of Iran and Turkey at the height of 290m flows from west to east through lands with steep slopes and passes the length of about 70 kilometers to reach to the Khoy city of west azarbaijan. After leaving Khoy the river turns north and flows through Evaghly valley where joins to Zilber Chay river and extends until ýmeets Agh Chay river at Marakan country. The river with its first name at Farhadi border outpost connects to the Aras ýriver. ý
For current study 133 data pairs of flow discharge and related bed load sediment were considered from Yazdakan Bridge gauging site. The duration of collecting data started from January of 1999 to September of 2009 by West Azarbaijan regional water authority. Monthly data of bed load sediment and discharge related to the time of experiment were recorded. For constructing each model the data set was divided into two groups which the first 25% of date pairs as group one was utilized for testing and the second group including 75% of data pairs employed for both training and validation checks.
In this study discharge flow data was utilized as input to each of ANN sediment rating curve (SRC) techniques separately so as to estimate ýbed load sediment. An idea to optimize the results of ýSRC by ANN, navigate the author to a hybrid model made ýfrom these two called HAS in a way that the error of SRC was predicted using ANN. Finally obtained results demonstrate that the HAS model is in good agreement with the observed ý bed load sediment concentration ývalues; while that depict better results than SRC and ANN models. For example the root ýof mean square error is 213.44 ton/day for HAS model, while it is 262.028 ton/day and ýý238.305 ton/day for ANN and SRC models, respectively. In general, it is illustrated from the ýresults that HAS hybrid model presents better performance to compare whit other models.

Soil salinity is one of the main issues in arid and semi-arid areas with shallow water level that is influenced by climate, soil type, crop type, irrigation water quality, water level and groundwater salinity. One of the major salinity problems in agriculture is accumulation of soluble salts in the root zone, which reduces plant growth and vigor by altering water uptake and causing ion-specific toxicities or imbalances. Establishing a good drainage system is generally the cure for these problems, but salinity problems are often more complex. Proper management procedures are needed to control saline drain water, because saline drain water can negatively affect the environment. Currently, about 23.5 million hectares which is about 14.2 percent of the total area of Iran suffer from salinity. And about 30 percent of irrigation lands are subjected to salinization, due to the high salinity of groundwater and shallow groundwater levels; therefore, the land leaching is necessary. Discharging of low quality drainage water in areas such as khuzestan is related to shallow groundwater with high salinity. Drain depth is one of the key factors that affect drain water quality by radial flow of underground water. In this study, temporal variation of drain water salinity and ground water salinity are evaluated using different irrigation water and drain depth installation.
Experiments were performed in a flume with 1.8 m long, 1m wide and 1.2 high that placed in the water management laboratory department of water engineering, Bu-Ali Sina University, Hamedan. Drains were installed at 20, 40 and 60 cm depths. To avoid the pores of drainage pipes being blocked, a plastic nets was used as a cover around the pipes. The bottom of the model was assumed to be the impervious layer. For irrigation on top of the model, a surface irrigation system was used and for measuring input discharge to the system a volumetric method was used. Saline water prepared by dissolving NaCL was added to subsurface reservoir to simulate a ground water with 65 dS/m salinity. The salinity of irrigation water at the study was about 0.321 dS/m. The soil profile below the tile drains was divided into multi layers with identical thickness of 10 cm. The measured initial electrical conductivity of each layer was 65 dS/m. Irrigation water deliveries were 0.14, 0.11 and 0.07 lit/sec. In order to determine the salinity of each layer of soil, a network of piezometers was installed on the model at different depths and with spacing of 15 cm from each other. As soon as exiting of drainage water from the drainage, outflow measurement and sampling from drainage water starts, and when concentration of drainage water reach to twice of the irrigation water salinity, will be continued. Also throughout whole experiment, with the help of network of installed piezometers on different distances and depth, groundwater salinity was measured with time intervals of 5 to 10 minutes. After completion of each experiment, reading salinity of each samples were performed using EC meter device.
The results show that the outer flow path is affected by the drain depth and the hydraulic head. When the inflow discharge increases, the hydraulic head and the mixing depth also increase. In addition, increasing the drain depth increase salinity of drainage out flow. It can be stated that when the drainage installing depth increases, the hydraulic head increases and the quantity of the salinity of drainage outflow increases. Infiltrate the flow lines into the depths, cause to the higher contribution of groundwater with low quality will be outing the drainage water from the drainage. This finding is useful in the regions with shallow and saline ground water table. In this research, the maximum salt concentration of the drainage water was achieved with 39.65 dS/m (about 7.44 kg of salt) for 60 cm drain depth and 0.14 lit/s irrigation water. However, the minimum salt concentration of the drainage water is 29.37 dS/m (about 2.41 kg) for 20 cm drain depth which is being irrigated with 0.07 lit/s. Therefore we can see that by increasing the drain tube installing depth, water level increased; thereby water flow penetrate to further depths, this action increases the required time for reaching to equilibrium of the area of below the drain tube.

Weir is one of the most applicable instruments for flow control and measurement in open channels. Accurate measurement of discharge in irrigation channels is vital for irrigation management. Weirs are designed as control sections for providing a unique relationship between the discharge and water head. In current study, theoretical and experimental characteristics of flow through a weir located in a horizontal circular channel were investigated. Choosing of this structure is due to lack of adequate studies on governing hydraulic equations of this kind of channels and its practical characteristics. In this research, discharge through the weir located at the end of a horizontal circular channel was developed from a theoretical viewpoint, and then calibration of this theoretical discharge equation was done via the discharge coefficient. The experimental data obtained in the study were also used to develop an empirical discharge coefficient relationship.
Theoretical discharge equation:The discharge equation of the circular weir ends up incomplete elliptic integrals of the first and second kinds, which are not very suitable for practical purposes due to their complexity. The theoretical discharge over the weir, Qt, can be expressed as:in which F(a,b) is approximated using the method of undetermined coefficients as:where g is the gravitational acceleration, h is the flow depth above the weir crest, D is the channel diameter, , , , and P is the weir height.
Introducing the discharge coefficient, Cd, yields the following equation for actual discharge, Q, of the weir.
Experimental setup and discharge coefficient equation: Determination of discharge coefficient, Cd, needs measuring the actual discharge (experimental or field data). The experiments were performed at the hydraulic laboratory of the Irrigation and Reclamation Engineering Department, University of Tehran. In order to collect experimental data, the weir was installed at the end of two horizontal circular channels with nominal diameters of 200 mm and 300 mm, and numerous measurements of different parameters that may have effect on discharge coefficient were carried out. An opening was provided on top of the pipes for flow head measurements by the point gauge. Water head over the weir crest was measured at a distance of 0.45 m upstream of the weir section. The weir plate was made of 10-mm-thick PVC sheet with a crest thickness of about 1 mm, and the downstream edge bevelled to a 45° angle (sharp-crested weir). For water heads over the weir crest smaller than 1.5 cm, in some cases clinging flow did occur and thus there was no atmospheric pressure under the lower nappe. Though, for heads greater than 1.5 cm a clear lower nappe profile with atmospheric pressure underneath was formed. Effects of surface tension and viscosity forces on the discharge coefficient, Cd, became pronounced at low water heads. Viscous and surface tension effects on discharge coefficient are neglected in this research. This is owing to operating range of the weir (minimum water head of 2 cm), which forbids surface tension effects and eliminates viscous effects. The experimental coefficient of discharge is computed for each data set collected in this study for known values of D, h, P and Q. A total of 350 tests were conducted to collect the data in the discharge ranges of 0.5 and 45 l/s. Suitable empirical equations for discharge coefficient were proposed using the 70% of the experimental data, and remaining data (30%) were used for validation procedure.
Proposed empirical equation for discharge coefficient: Using the curve-fitting technique, the following equation is obtained for CdThis empirical equation is valid for 0.095≤h/P≤1.8, 0.27≤P/D≤0.73 and 0.05≤h/D≤0.56. The assumptions made in deriving the above empirical equation of discharge coefficient are that the channel slope is horizontal, the flow is free and surface and viscous tension effects on Cd are negligible. A comparison of the experimental discharge coefficient with computed ones using the proposed empirical equation for all of the experimental data, the calibration data set and the validation data set showed that the computed discharge coefficient values are well within ±5% of the observed data for all three data sets. The average relative error of computed discharge coefficient using the proposed empirical equation for discharge coefficient Cd compared with the observed values is less than 5% for 95% of all experimental data. The results of this study reveals that a weir with low flow height is more sensitive to water flow depth, and weirs with more height are less sensitive to upstream flow head variation and thus are more reliable for flow measurement.

Water infiltration into the soil is one of the most important components of the hydrological cycle. Land use cover changes are affected by human-induced activities and growth socio-economic factors expansion of the forests, grazing, agricultural activities government policies and environmental factors such as drought. In the rural region people encroach on forest areas for conversion to other uses, mainly cropland and rangeland though the land is not suitable for these purposes. The conversion of forests to other lands uses cause increase water erosion, mass movements, and soil compaction by trampling and alteration of the hydrology cycle, among others. The aim of this study was to analyze the effect of some land uses on amount of water infiltration and parameters of some infiltration models in forests, rangeland and agricultural land uses. This research was conducted at Fandoghlou sylvan region, located in Ardabil Province, that districted by Namin, Astara and Hir county (38, 10 to 38, 30 East and 48, 30 to 48, 45 North). The acreage of the study area is 16000 hectares. Fandoghlou forest region is continuance of Gilan semi tropical forest. The elevation in the catchment ranges between 1500 and 1850 m, and average of precipitation amount was recorded 290.4 mm by Ardabil synoptic station. Water infiltration experiments were conducted in Fandoghlou region of Ardabil using double ring infiltrometer in forest, pasture and agricultural land uses in three replication. Totally 9 experiments were carried out in saturated state. Experiments were continued until at least 3 consecutive head fall data of double ring infiltrometer have been constant. Minimum time of infiltration experiments were 120 min. Initial water content were measured before water infiltration tests beginning, that amount of water content in forest land use was more than that in pasture and agricultural land use. A disturbed soil sample was collected from each different land use to measuring of soil physical and chemical properties. Organic carbon percentage was measured by organic carbon oxidation method. Bulk density and saturated hydraulic conductivity were determined by the core method (Undisturbed soil samples were taken with steel core samples of 98.125 cm3). Soil pH and Electrical conductivity were measured by a pH and a conductivity meter. In this study, water infiltration rate was estimated using the five infiltration models including Philip, Kostiakov, Kostiakov-Lewis, Green-Ampt and Horton. To determine the best model of mentioned models in each land use, three statistical parameters RE, RMSE and R² were used. Results showed that for three land uses including forest, pasture and agriculture, the Kostiakov-Lewis (RE, RMSE and R² is equal to 1.614, 0.023 and 0.9119 respectively), Green-Ampt (RE, RMSE and R² is equal to 2.824, 0.056 and 0.9196 respectively) and Philip (RE, RMSE and R² is equal to 2.901, 0.046 and 0.8408 respectively) models with less statistical error are the best models for infiltration rate simulation respectively. Minimum and maximum amount of A parameter of Philip infiltration model in pasture (0.179) and forest (0.2) land use, S parameter of Philip infiltration model in forest (0.472) and pasture (0.1.486) land use, a parameter of Kostiakov infiltration model in pasture (0.682) and forest (0.821) land use, k parameter of Kostiakov infiltration model in forest (0.547) and pasture (1.347) land use, a parameter of Kostiakov-Lewis infiltration model in pasture (0.217) and agricultural (0.379) land use, b parameter of Kostiakov-Lewis infiltration model in forest (0.011) and pasture (0.044) land use, c parameter of Kostiakov-Lewis infiltration model in pasture and forest (0.23) and agricultural (0. 21) land use, A^' parameter of Green-Ampt infiltration model in forest (8.469) and pasture (66.966) land use, B^' parameter of Green-Ampt infiltration model in pasture (13.188) and forest (14.516) land use, k parameter of Horton infiltration model in pasture (4.514) and forest (11.23) land use, was calculated.
Philip and Green-Ampt infiltration models have best closeness than that of other models in infiltration rate simulation, because both of them have physical base. Horton infiltration model at pasture and agricultural land uses had maximum statistical error and have an over-estimating on infiltration rate. In forest and agricultural land use, Kostiakov-Lewis infiltration model over estimated the infiltration rate and under estimated in pasture land use. In agricultural land use, Kostiakov infiltration model under estimated the infiltration rate and over estimated in pasture and forest land use. Minimum sorptivity coefficient of Philip infiltration model has been extracted in forest land use, because matric potential of this land use was less than that of pasture and agricultural land use. Initial water content of forest land use was more than that of pasture and agricultural land use. Maximum empirical (B) coefficient of Philip infiltration model, also has been extracted in forest land use, that indicate in this land use soil structure was better than that of other land use, because in forest land use the amount of organic matter was more than other land use.

Nowadays, the need for countries to design water distribution networks and abundant costs of water transfer projects, lead us to the use of new and effective methods for designing and optimizing water distribution networks. Practically, engineers, based on engineering judgment, traditionally use methods of trial and error in order to find a suitable solution. Many research have been conducted in the field of optimizing methods because traditional practices do not guaranty an approach to optimized, or even close to optimized, answer. Choosing the appropriate system would be done using different approaches. One of these approaches, which has been used in present study, is the Method of Linear Programming. In the practical method of this study, in compliance with the technical limitations, a water supply system will be optimized to prevent hydraulic patrimonial flows. Using this method, we can optimize all costs of structures including purchasing, Implementation and maintenance, by making them Linear. Therefore, an objective function which represent the minimizing of the costs and Linear equations that represent the technical limitations were defined. Each Linear programming equation contains three basic steps including Objective Function, Limitations (for example Suitable pressure range, Standard speed range and pipe diameter) and Decision Variables which, in this study, are defined for water supply systems. In present study, this process was configured for a real water supply project. The design, which is studied in this research, is the water supply project to the rural area of “Behbahan Qala Madrese” that covers about 720 hectares of the district. With regard to the existence of rivers, and also roads and farms in the area, the net cultivated area was estimated about 625 hectares. The distance this land from the nearest river (Kheirabad River) is about six kilometers. Then, by defining Objectives Functions, Constraints of issue and Variables in LINGO, were optimized and results were compared with various practical conditions. In order to define various practical conditions, ten scenarios were defined using traditional and trial and error based methods. These scenarios, before and after the installation of protective structures, were hydraulically implemented in WATER HAMMER and the results of costs of each scenario, separated into purchase, implementation and operation, were extracted. In the next step, similar to practical condition, optimizing results of LINGO model including pumping system, pipe diameter, type and size of the protective structures were implemented in WATER HAMMER under tow conditions, before and after implementation of protective structures. After that, the results of optimizing by LINGO were compared with the results of practical method. According to the results, Programming Method is capable of optimizing all major parts of the implementation of the branch networks. This method incorporates an approach with high potential for optimizing; in a way that best pumping system will be extracted using pressure limits (between 20 to 100 meters of water column) and water speed in pipes (maximum 1.5 meter per second), optimum diameter and with compliance with price limits of pumps, electricity and required system pressure (according to the topography of the land). In other hand, best protective structures will be chosen in order to prevent patrimonial hydraulic flows including Water Hammer and/or Negative Pressure in water supply system. Eventually, hydraulic simulation was conducted by implementing the results of LINGO into WATERHAMMER. In this research, all three parts were simultaneously defined in the Objective Function and all restrictions were taken under consideration in order to optimizing the entire system because of the effect of pumping system, piping network and also protective structures on patrimonial flows. Using Linear Designing Method will prevent wastage of national resources in addition to improving design speed and economic efficiency. Defined practical scenarios, by changing pipe diameter, pumps and protective devices, were configured as a combination; practical scenario number 10 had the lowest implementation cost compared with other scenarios. However, Linear Programming results indicated that more costs can be reduced; in a way that, comparing the costs of implementation of the transfer line in this scenario with the costs of optimizing method by Linear Programming reviles that a reduction of 3.39 in piping sector, 17.34 in buying and planting pumps, 2.74 in protective structures and finally 3.69 in total costs of the project would occur.

Due to widely used sprinkle irrigation systems, it is necessary to prepare a develop model to estimate evaporation and wind Drift losses. Parameters and many factors are effective the amount of losses due to evaporation and wind in the sprinkle irrigation systems. These factors can generally be divided into two categories of climatic parameters and the system. The purpose of this study is the assessment of proposed equations by some former researchers (Montero et al., Trimmer, Frost and Schwalon, Keller and Bliesner) to estimate of evaporation and wind drift losses of sprinkle irrigation systems in the Sanandaj city. The standards ISO 7749-1 and ISIRI 8995-3 and single sprinkler method have been taken to determine evaporation and wind drift losses for 3 sprinklers (AMBO, ZM22 &.ZK30). The nozzle diameter of sprinklers were ZM22 (10, 3.5), AMBO (10, 7) and a sprinkler ZK30 (8, 3.5) mm. To supply sprinkler operating pressure was used of a device dry horizontal electro pump. The main pipe was of polyethylene with an outside diameter of 160 mm. The butterfly valve in the bypass pipe was used to adjust of the pressure of model. A Sub main polyethylene pipe was used with a diameter of 50 mm and a length of approximately 120 m to conveyance water to the sprinkler. In this study was considered riser height 165 cm. Sprinkler pressure was measured at the point of the riser. This point was lower than the point of changing of riser diameter. This distance must be at least 10 times the diameter of the riser. For measure discharge of sprinkler was used volumetric.Then the test zone was an area of 60 × 60 square meters networking. The test zone was networked by using plastic meter and wooden sticks (3m×3m), and water collecting buckets each with 90 mm height and 80 mm of internal diameter were installed. The minimum of test time was 1 hour. This investigation is performed to assess effect of different intensities of wind and pressure amount at 4 pressure of system (3, 3.5, 4 and 4.5 Bar), at 2 types of wind velocities (0-1.8 calm wind, 1.8-4.4 average wind) were applied.On-site testing wind speed with a handheld anemometer at a height of about 2 meters were measured and temperature and relative humidity by TESTO 615 device.
The results of linear regression showed that the results of methods of Montero et al.(2000) and Keller and Bliesner (1990) per 3 sprinklers ZM22, AMBO and ZK30 had significantly different from the actual amounts of losses due to evaporation and wind.Also computational results of Frost and Schwalon had significantly different in both sprinklers of Ambo and ZK30 at probability 5 and 1 percent respectively and has not significantly different in ZM 22.In both ZM22 and ZK30 sprinklers computational result of Trimmer(1990) method are not significantly different with actual result of losses due evaporation and wind but in Ambo sprinkler was significantly difference at probability level 1 percent. In three studied sprinkler Montero et al.(2000) equation showed amount of losses more than actual losses but Keller and Bliesner (1990) method was less than actual losses. Also result of Frost and schwalon (1955) in both of Ambo and ZK30 sprinkler and Trimmer method in the Ambo sprinkler are less than actual amounts. Also, based on NRMSE, the accuracy of all models is weak to estimate losses due to evaporation and wind in all three studied sprinkler. Accuracy of the results obtained from a trimmer (1987) for ZK30 sprinkler was at the border of moderate to weak.
The results of both methods to evaluate of the accuracy models have shown that the used models for estimation of losses due to evaporation and wind for studied sprinklers in the fixed head sprinkle irrigation systems failed and could not be verified in the city of Sanandaj. The lack of models comprehensive of climate variables, system and hydraulic is reason for their failure for estimation of losses due evaporation and wind for studied zone. Also to evaluate the accuracy of the equations of provided in this study was used NRMSE index. Amount of this index was in the range of 14 to 19 percent for these equations. The accuracy of these models will be assessed good according to the classification of this index.

Sedimentation in dam reservoirs is an important issue which requires to be considered within the operation life of the dam. In order to maintain long time storage in dam reservoirs, sediment removal from reservoirs is an essential issue. There are numerous methods to perform this goal. One of the known Sediment removal methods is hydraulic flushing. This method is classified in two free and pressure classes. Pressure flushing is considered as an effective method in removing local accumulated sediments behind the dam and around the location of valves and turbines. During the flushing operation, water level in the reservoir creates pressure on the sediment, causing the removal of the sediment and after a while of flushing a funnel shaped crater is created in the vicinity of the bottom outlet opening. In this study, the effect of expansion of bottom outlet channel within the reservoir on the dimensions of the flushing cone, also its hydraulics were investigated.
The experiments were conducted with a physical model of a rectangular box with 7m length, 1.4m width, and 1.5m height, consisting of three parts namely the inlet of the model, the main reservoir, and settling basin. In the inlet of the model, the turbulence of the inflow is disappeared and a uniform flow enters the main reservoir. Since in pressure flushing the water surface level inside the reservoir is constant during the operation, the water level is adjusted by using a spillway positioned in the inlet of the model during the whole procedure. The main reservoir of the model was 5m long and the sediments were placed within this part of the model. The sediment particles used were non-cohesive silica sediments with uniform size and with median diameter(d50) 1.15mm and geometrical standard deviation(σg) 1.37. In order to perform flushing, an outlet made of Plexiglas with the diameter of 5cm aligned with the central line of flow was used. To investigate the effect of the bottom outlet channel expansion within the reservoir on the dimensions of flushing cone, the experiments carried out with different discharges and water depths above the bottom outlet in different expansion size of outlet channel in constant sediment level of 20cm above the center of the channel. Also experiments in the same hydraulic conditions without channel expansion within the reservoir were conducted as control tests. To perform the experiments, first the Plexiglas tube was positioned in its place as the outlet channel. The model was slowly filled with water until the water surface elevation reached to a desired level. The bottom outlet was manually opened until the outflow discharge, become equal to the inflow discharge. After a while the sediments were discharged with the water flow in very high concentrations through the outlet channel (sudden discharge) and a funnel shaped crater was formed in front of it. At the end of each experiment, the flushing outlet was closed in which the incoming discharge was set to zero then water was carefully and slowly drained from the main reservoir. After the run of each experiment, the bed level of scouring was measured using laser distance meters with the accuracy of 1mm, and the volume of flushing cone was calculated by Surfer 10.0 software. In order to investigate the hydraulics of the flow, the measurement of flow velocity in the flow rate of 3 liters per second and reservoir water level of 47.5cm for three expansion sizes of outlet channel (10, 20, and 30cm) was performed. The flow velocity measurement was done using an Acoustic Doppler Velocimeter with a sampling rate of 200 Hz. This device is capable of measuring moment velocities in three directions (velocity in directions x, y and z are u, v and w respectively).
Results showed that, the expansion of bottom outlet channel within the reservoir has positive effects on the dimensions of the flushing cone. Therefore, the relative amount of bottom outlet channel expansion for 0.5, 1 and 1.5 times height of the sediments in the reservoir, leads to increase in flushing cone length for average of 48, 83 and 113% and flushing cone volume for average amount of 50, 74 and 96% compared to the case when the outlet channel is not developed. Using experimental results, two equations with good estimation are presented for calculating the flushing cone volume and length. Also the results indicate that, with increasing in the Froude number, sediment discharged from reservoirs is increasing, as in the higher expansion size of the bottom outlet, effect of the Froude number on the amount of the sediment discharged is high. The analysis of the flow hydraulics indicates that, the flow velocity vectors while getting closer to the outlet opening, lose their expanded status and velocity gradient in the adjacent areas increases significantly. The analysis of results for flow velocity measurements are presented in detail in this paper.

Stability of soil and water resources in agriculture, above all depends on the type of resource utilization and cropping pattern. Nowadays, Maximization of factors such as income, job opportunities and minimization costs as the economic and social aspects along with the limitations of arable land and water is considered. One of the most important questions is the issue of sustainability, how to evaluate, measure and analyze sustainability. One of the methods and models to assess the stability is mathematical programming approaches. Application of these models for agricultural planning has a long history and a wide range. But using a particular type of this models to assess the sustainability, means fractional models is a new topic. Lara and Stancu-Minasian (1999) examined the theoretical aspects of this model in a research titled as “Fractional programming: A tool for the assessment of sustainability”. As mentioned above, there are three main objectives for sustainable crop pattern, maximization income and job opportunities and minimization costs (In this case water consumption). Using fractional programming provides the possibility to make three goals in two goals which include maximization of “the net profit/water consumption” and “making job opportunity/water consumption”. In this way, the number of solutions is lower and therefore the decision-making process is easier. Fractional programming for planning and optimization cropping pattern has not been done yet. This paper is being studied to evaluate the stability in the agricultural systems of Bajestan plain in the Razavi Khorasan province; and also determine the best cropping pattern according to that. There are about 10,000 hectares of agricultural lands in the plains Bajestan. These lands are cultivated in seven major crops which include barley, saffron, wheat, pistachios, cotton, pomegranate and melon. Now the area under cultivation of these crops is 2250, 1630, 1500, 1400, 1200, 1350 and 670 hectares, respectively. In this region, about 70% of the working population are employed in agriculture.To verify the effectiveness of the fractional models first of all, three mono goal linear models were prepared. The goal of each of these three models was maximization income and maximization job opportunities and minimization water consumption. By solving those models, three cropping patterns A1, B1 and C1 was obtained. For combination the triple dimensions of social, economic, and environmental, two relative criteria have been explained as the indications to evaluate system stability. Thus, In the next step, by dividing each of the two functions (maximization income and maximization job opportunities) to water consumption, two new objective function were obtained in the form of fractional model. In fact, this two models represent two sustainability index. By solving those models, two cropping patterns A2 and B2 was obtained. Finally, an ideal fractional/mathematical programing model was prepared in which the last two functions were optimized. Optimization in relationships “the net profit/water consumption” and “making job opportunity/water consumption” leads to new copping pattern (C2).In optimized cropping pattern the area of barley, saffron, wheat, pistachios, cotton, pomegranate and melon obtained 111.4, 1608, 110.8, 7202.3, 103.1, 404.8 and 159.5 hectares, respectively. With the aim of maximizing the net profit, two relative criteria (“the net profit/water consumption” and “making job opportunity/water consumption”) in fractional model to the linear increase 17.3% and 19.0%, respectively. With the aim of maximizing “making job opportunity”, two relative criteria in fractional model to the linear increase 25.2% and 22.1%, respectively. In multi-goals programing approach, two relative criteria in fractional model to the linear increase 32.4% and 42.5%, respectively. Overall, the ratio of income to water consumption in three cropping pattern of linear programming (A1, B1 and C1) is lower than three cropping pattern of fractional programming (A2, B2 and C2). The values are respectively 17.8%, 26.7% and 33.3%. Also, the ratio of making job opportunity to water consumption in three cropping pattern of linear programming (A1, B1 and C1) is lower than three cropping pattern of fractional programming (A2, B2 and C2). The values are respectively 18.9%, 22.1% and 42.5%. It can be concluded that fractional models in terms of both sustainability index are superior to the linear models. These results are consistent with previous results and confirm it, such as Castrodeza et al. (2005), Maros et al. (2009), Hu et al. (2010) and Sabaghi et al.

Background & objectives & Today, climate change has effect not only on the management levels of water resources but also has some implications in everyday life. Study of changing in key variables of temperature and precipitation with regard to the effects of climate change in coming years can be helpful for solving some problems such as drought, sudden floods. Since others researchers, have performed their analysis more than one stationary and just had to show changes in quantity, in this study it was trying to analyzes by location (region) is also to be considered. As well as increasing the number of models and downscaling techniques and the future simulation of periods due to increased uncertainty in the results of climate change, in this study, only a regional model and a downscaling methods were used. The purpose of this study is to investigate the effect of climate change on precipitation changes and extreme rainfall events in the next period (2040-2011) in two selected stations in Golestan province. In this study, it is used data from the database of Climate Research Unit (CRU), under four emission scenarios A1, A2, B1 and B2. HADCM3 regional model was used as boundary conditions. This model in the fourth assessment report (2007) was published and new models is for applied modeling. Rainfall data of two weather stations Ali abad Katoul and Mazrae nemooneh artesh, as the both Humid and semi -arid stations in Golestan Province, were downscaled by proportional method. And then precipitation data were interpolated using IDW (8) as statistical method, and finally the time series scenario of future climate change were calculated by the change factor method. To investigate number of occurrences of heavy rainfall with precipitation index greater than 50 mm was considered and high-risk months in each station, the incidence of extreme rainfall was predicted.
The results show that precipitation changes for both stations in autumn and early spring and winter and late and mid-summer increases. The maximum rainfall in November and January is expected that the increased intensity of floods warns at the beginning of winter. In Aliabad Katoul station with humid climate, precipitation changes for A1 scenario will occur with more intensity and more increase precipitation during autumn and early winter and late summer would be expected. In the more scenarios and in all seasons, changes in seasonal rainfall, increase in seasonal rainfall in the regions studied show. The largest increase precipitation in both stations, is occurred under the B2 scenario. The number of extent occurrences is expected to increase in future period, the increase in Ali abad Katoul station more will happen in late summer and early fall, but in Mazrae nemooneh artesh station in late autumn and early winter will increase, as well as the most of increase in extreme events Looking at the chart in more Ali abad katoul station of Mazrae nemooneh artesh. Also it is expected in the future, the extent precipitation will increase and the highest increase in Aliabad and Mazrae nemooneh artesh stations would happen in November and January, respectively. The number of high rainfall events (greater than 50 mm) and high precipitation levels increased in both stations; if the rate average precipitation not show significant changes. As a result, it can be concluded that the probability of occurrence of more heavy rainfall this has been an increased amount of annual rainfall. The results indicate that climate change could increase extreme events in Golestan province was rainingso that by increasing levels of carbon dioxide, the daily limit will increase the number of days with precipitation; in fact, it would be an increased frequency of flooding in the Golestan province.
Results from the base period 2010 -1981 and the future period 2040 -2011 have been analyzed and evaluated.
Results showed increasing in mean of annual precipitation Ali abad Katoul and Mazrae nemooneh artesh stations around 6/7 and 73/8 percent, respectively. Also expected in future period, the number of extent precipitation events will increase. Climate change could increase the number of extreme events precipitation in Golestan province, so that with increasing levels of carbon dioxide, the number of days with some precipitation will increaseIn fact, it would be an increased frequency of flooding in the Golestan province.

By development of urbanization in metropolitan and reducing permeable surfaces, problems occur during precipitation including the increase of runoff volume and high level of pollution in canals and streams. One of the modern and effective ways for management of urban runoff quantity and quality is the application of Best Management Practices (BMPs) which are widely used for reduction of non-point source pollution and runoff peak flow. BMPs for runoff consists of structural and non-structural types. Structural practices include physical measures and executive projects such as ponds, vegetated swales, bioretention cells systems, permeable pavements and infiltration trenches which are developed with the aim of runoff impacts reduction. Non-structural practices are the measures done through law enforcement and educational programs. The main challenge for designers and decision makers is the selection of optimum combination of practices among various available alternatives. The best choice should be cost effective, accessible and executable in the specified region. The aim of this research is to determine the best choice scenario for urban runoff pollution reduction which is cost-effective. In this regard, Strom Water Management Model (SWMM) is used to assess the defined scenarios and BMPs which are applied in a subbasin of Tehran metropolitan. Strom Water Management Model (SWMM) is a dynamic model used for simulation of precipitation- runoff i.e. water quantity and quality of runoff from a precipitation event and long term simulation of runoff in developed urban areas. The practices used in this study include four systems of vegetated swales, bioretention cells systems, permeable pavements and infiltration trenches. Vegetated swales are wide shallow channels that are covered by plants and are designed to slow down the runoff and increase the infiltration and pollutant removal while directing the runoff. Permeable pavement consists of a permeable surface that provides infiltration and storage of runoff and a pavement for traffic. Infiltration trench is a drilling groove that is filled with crumbs and forms a subsurface pond. Bioretention cells systems consist of a biological surface layer, a soil sand layer and retention layer which applies the chemical, physical and biological features of plants, microbes and soil for pollutants removal from runoff.
Using SWMM model critical subbasins are identified and the effectiveness of BMPs are assessed. Afterward, scenarios are defined based on the acquaintance gained about the performance of subbasins and BMPs through modeling and sensitivity analysis. For water quality simulation in the model, total suspended solids (TSS) and chemical oxygen demand (COD) are selected. For the case study region, four types of landuse including residential with low and high density, street and highway are defined. Return period for the flood is considered 2, 10 and 100 years. Dynamic wave method was used in hydraulic routing and Horton method was used for modeling the infiltration. The soil type of the case study area was sandy loam and its parameters such as hydraulic conductivity and permeability were necessary for Horton method. To model the pollutant washing event mean concentration method (EMC) was used. The basic value and the range of EMC for TSS and COD were chosen from EPA report and literatures.To determine the best combination of BMPs in subbasins various scenarios are defined. In this regard, firstly six basic scenarios including five structural and one non-structural BMPs were applied in sensitive subbasin to assess their effectiveness in runoff peak flow reduction and pollutant removal. Afterward, 15 scenarios were defined based on the previous six scenarios and their combinations. The scenarios were simulated in SWMM and the results were assessed and compared based on an index defined as the ratio of percent removal to the cost of scenario. This index was called optimality index which shows the cost effectiveness of each scenario.
The results showed that applying these BMPs can cause a considerable reduction in runoff flow and pollution load. The subbasins characteristics which have the greatest impacts on runoff water quantity and quality are three factor including surface permeability and percent of runoff routing to the pervious surface and land use. The first two factors are used in designing and defining the non-structural BMP. Thus, increasing these two quantities are suggested as applying non- structural practices. The third factor (landuse) is used for determination of critical subbasins. Comparing the results of BMPs performance using the optimality index showed that infiltration trenches have a better performance due to higher optimality index. Also in the scenario that the combination of all four structural BMPs was used, 70% TSS removal with the cost of 16.4 billion Rials was obtained. In general, the BMPs that have a higher optimality index, like infiltration trenches, have a better performance, but the executive factors and the existence of suitable space are involved as limiting factors.

Random-like behaviors in various natural phenomena led researchers to apply more accurate forecasting methods. While Statistical models are more traditional to use for such complex behaviors, Chaos theory has been paved a new way to hydrologists and water engineers. In Chaos theory viewpoint, random-like behavior can be related to a simple determinism which is hidden in the background of system dynamics and can be shown in an optimized phase space. If conditions of a chaotic system which Chaos Theory has been stated dominate the system behavior, dynamics in the phase space follows a fracatal pattern which is aforementioned hidden determinism and called the attractor. The case study is the Kashkan River which is located in southwestern of Iran, Lorestan province where semi arid climate is predominant. While number of dry days reaches to 185 in year, average precipitation is 375.3 mm during a water year. The daily runoff time series of the Kashkan River have been analyzed using Chaos theory, following its observed random-like behavior. To perform chaotic analysis, a phase space should be reconstructed by determining optimize time delay and embedding dimension.Various methods has been suggested to calculate the time delay including the Average Mutual Information method which have been gained more popularity among the others. In this paper, a new method has been presented to estimate optimize time delay in the base of the AMI method. Therefore, instead of using first local minimum of Mutual Information Function, its overall minimum has been considered to estimate optimize time delay. This method has been applied to daily runoff time series of the Kashkan River and its efficiency has been studied in fractal dimension estimation methods. While False Nearest Neighbors and Correlation Dimension methods have been employed to evaluate fractal dimension of system attractor, Sensitivity to initial conditions have been studied using Lyapunov Exponent and Kolmogorov Entropy methods as the other majar feature of chaotic behavior.
At first part of this study, AMI method and Mutual Information Function have been examined theoretically by evaluating its performance in a chaotic map called Rossler Map. It has been shown that first minimum of MIF can be an optimize option to form best illustration of system chaotic attractor.While the first local minimum is more effective to mathematical functions such as RM, some other issues should be considere when the case study is a natural system where MIF can have many minimums in different local sections. As mentioned earlier, overall minimum of MIF have been used to determine time delay as a new method phase space reconstruction which is obtained τ =107 days. False Nearest Neighbors and Correlation Dimension method have been used to evaluate fractal dimension, which showed the existence of a fractal attractor in phase space, and also the superiority of new method for phase space reconstruction. Positive Lyapunov Exponent is a sign of sinstivity to initial conditions and therefore, chaotic behavior in system, which is more emphasized by calculating Kolmogorov Entropy in 3 different radius. Regardless of the radius is selected, KE reaches to a finite number which is an evidence of chaotic behavior. While a certain number can not be calculated for Kolmogorov Entropy, it can be observed that by selecting a
1 - MSc Student of River Engineering, Jundi-Shapur University of Technology, Dezful, Iran.
2 - Assistant Professor of Civil Engineering, Jundi-Shapur University of Technology, Dezful, Iran.
*- Corresponding author: moshfegh@jsu.ac.ir, P. O. Box: 64615-334
Received: 2009/08/08 Accepted: 2010/11/11
smaller radius, KE reaches to a fininite positive number. Hence, system entropy is consistent and follows a chaotic pattern.
Results indicated Chaos existence in this time series and suitability of Chaos theory-based models for governing system of flow in the Kashkan River. Sensitivity to initial conditions and fractal attracor as two major characteristics of chaotic system has been observed. In addition, a new AMI-based method to determine optimize time delay has been showed better indication of system chaotic behavior in phase space. Compared with traditional approach, the attractor which has been formed in reconstructed phase space behaves more constantly by increasing embedding dimension in both FNN and CD methods. In comparison to similar studies with times series with different lengths, it can be concluded that length of a time series can not effectively adjust overall conclusion in chaotic analysis of the Kashkan river flow governing system. Generally, evidences of chatic behavior in the Kashkan riverflow time series has been confirmed. Hence, employing chaotic models can be very helpful to forecast.

Water is becoming a scarce and precious resource all over the world. Nowadays, irrigation has allocated 69 percent of the 3240 cubic kilometers of human consumed water and 87 percent of the total consumed water and transformation of dry lands into irrigated areas with correct operation, reasonable utilization and good maintenance could be greatly effective on increasing of human needed products. Accomplished fact all over the world is that most of operating irrigation and drainage projects don’t redound to objective points and not only they couldn’t successfully increase efficiency, but also they cause reduction in production levels by harmful effect on aforesaid resources. Reasons have almost been incorrect design and operation, unsuitable and insufficient utilization and maintenance and generally poor management in different Sketches. Ghoorichay reservoir dam is located in Ardabil province. This earth dam has clay core and storage capacity of this structure and usage volumes are respectively 18.07 and 17.71 cubic million meter. Ghoorichay irrigation and drainage network is situated downstream of the dam, which amount to 2200 ha area. Water is drawn from the reservoir and distributed through the main canal and many secondary channels to farms. Main canal is established along the kilometers, 13� to 20�, to convey and distribute water into 4 secondary channel named LC1, LC2, LC3 and LC4. This canal has 6.97-kilometer length, after LC1 turnout from kilometer 13� to 15폝 it is generated with trapezoidal cross section and 0.001 slope and 2.25 cubic meter per second discharge. This section of main canal has 1.2 meter width, 1 meter height and bank slope 1:1.5 (V:H). In this section of main canal, normal depth is considered 0.75 meter, free height 0.25 meter and normal flow velocity is 1.3 meter per hour.
In this study, first step to calibrate the gates is to choose the suitable place for flow measuring. So LC2 channel with 6- kilometer length and 20 turnouts considered the most important secondary channel in Ghoorichay irrigation and drainage network, is chosen and one of its slide gates with 1.15 meter width is assessed. It is necessary to notice that chosen point for measurement should be in a location with minimum swing and wave ruffling to decrease measurement errors in hydraulic characteristics such as water surface width and water depth. In addition, it shouldn’t be any other turnout close by measuring location in order to ignore water losses through the distance. Then, needed condition for operation should be created. So, water depth behind regulation structures should rise up to FSL or Full Supply Level and keep constant by proper regulation while measuring duration. Under this situation flow measurement in LC2 channel had done. Present structure in entry point of channel for measuring discharge is 3-foot Parshal flume. Having measured depth and discharge parameters in specialized points of channel and considering channel dimensions, turnout and regulator structures, flow condition simulates by hydrodynamic models Root canal and ICSS and results have gotten with 10 different turnout opening.
Considering amount of off-taking in upstream of LC2 channel and downstream demand of this turnout which is 600 liter per second, also with considering network efficiency equal to 80 percent and evaporation and head losses equal to 50 liter per second. After inputting data in models, simulation is done for one hour duration and discharge and depth amount is determined. In order to assess introduced hydrodynamic models, and after calibration of two models, this part is allocated to comparison of output results with measured results along studied reach. This comparison is included water depth in turnout and regulator location and simulated water depth along the studied reach. Comparison is accomplished by drawing figures and statistics survey of errors in different points. Finally comparing the best coincidence of results obtained from each model, with observed condition, the proper model is chosen. Result shows that in both simulation dates, 1391/3/20 with entry discharge equal to 0.95 cubic meters per second and 1391/3/21 with entry discharge equal to 0.79 cubic meter per second, calculated error in hydrodynamic model Rootcanal is fewer and better coincidence with observed data is seen. Although results shows that for Icss hydrodynamic model the parameters are equal 5.14 and 4.71 centimeter respectively and for Rootcanal hydrodynamic model they are equal 2.12 and 1.61 centimeter respectively. These results show better performance of Rootcanal model than Icss model for simulation and estimation of flow parameters in irrigation canals.

Iran was faced by droughts and water shortages recently, therefore determination of crop water requirement is important than ever. Lorestan province and Khorramabad region are the one of the largest producer of chickpea (Cicerarietinum L) in Iran, however no comprehensive research has been conducted to estimate the water requirement of chickpeas. The purpose of this research was to determine the crop coefficients of chickpea. A field lysimetric investigation was designed during one year 2013 in Faculty of Agriculture, Lorestan University to find (Cicerarietinum L) water requirement and different crop coefficients. Therefore, 4 drainable lysimeter was selected with diameter of 0.45 m and height of 0.8 m. The crop density was 50 plant per m^2, than by using of water balance model, the actual evapotranspiration was estimated. The 〖ET〗_cof Chickpea in the year of study was 438.04 mm. The potential evapotranspiration also was estimated by lysimeter. The value was obtained equal 550.20 mm. Finally, the crop coefficient for initial, development, middle and late season of Chickpea were estimated as 0.488, 0.955, 1.083 and 0.371.Iran was faced by droughts and water shortages recently, therefore determination of crop water requirement is important than ever. Lorestan province and Khorramabad region are the one of the largest producer of chickpea (Cicerarietinum L) in Iran, however no comprehensive research has been conducted to estimate the water requirement of chickpeas. The purpose of this research was to determine the crop coefficients of chickpea. A field lysimetric investigation was designed during one year 2013 in Faculty of Agriculture, Lorestan University to find (Cicerarietinum L) water requirement and different crop coefficients. Therefore, 4 drainable lysimeter was selected with diameter of 0.45 m and height of 0.8 m. The crop density was 50 plant per m^2, than by using of water balance model, the actual evapotranspiration was estimated. The 〖ET〗_cof Chickpea in the year of study was 438.04 mm. The potential evapotranspiration also was estimated by lysimeter. The value was obtained equal 550.20 mm. Finally, the crop coefficient for initial, development, middle and late season of Chickpea were estimated as 0.488, 0.955, 1.083 and 0.371.Iran was faced by droughts and water shortages recently, therefore determination of crop water requirement is important than ever. Lorestan province and Khorramabad region are the one of the largest producer of chickpea (Cicerarietinum L) in Iran, however no comprehensive research has been conducted to estimate the water requirement of chickpeas. The purpose of this research was to determine the crop coefficients of chickpea. A field lysimetric investigation was designed during one year 2013 in Faculty of Agriculture, Lorestan University to find (Cicerarietinum L) water requirement and different crop coefficients. Therefore, 4 drainable lysimeter was selected with diameter of 0.45 m and height of 0.8 m. The crop density was 50 plant per m^2, than by using of water balance model, the actual evapotranspiration was estimated. The 〖ET〗_cof Chickpea in the year of study was 438.04 mm. The potential evapotranspiration also was estimated by lysimeter. The value was obtained equal 550.20 mm. Finally, the crop coefficient for initial, development, middle and late season of Chickpea were estimated as 0.488, 0.955, 1.083 and 0.371.Iran was faced by droughts and water shortages recently, therefore determination of crop water requirement is important than ever. Lorestan province and Khorramabad region are the one of the largest producer of chickpea (Cicerarietinum L) in Iran, however no comprehensive research has been conducted to estimate the water requirement of chickpeas. The purpose of this research was to determine the crop coefficients of chickpea. A field lysimetric investigation was designed during one year 2013 in Faculty of Agriculture, Lorestan University to find (Cicerarietinum L) water requirement and different crop coefficients. Therefore, 4 drainable lysimeter was selected with diameter of 0.45 m and height of 0.8 m. The crop density was 50 plant per m^2, than by using of water balance model, the actual evapotranspiration was estimated. The 〖ET〗_cof Chickpea in the year of study was 438.04 mm. The potential evapotranspiration also was estimated by lysimeter. The value was obtained equal 550.20 mm. Finally, the crop coefficient for initial, development, middle and late season of Chickpea were estimated as 0.488, 0.955, 1.083 and 0.371.Iran was faced by droughts and water shortages recently, therefore determination of crop water requirement is important than ever. Lorestan province and Khorramabad region are the one of the largest producer of chickpea (Cicerarietinum L) in Iran, however no comprehensive research has been conducted to estimate the water requirement of chickpeas. The purpose of this research was to determine the crop coefficients of chickpea. A field lysimetric investigation was designed during one year 2013 in Faculty of Agriculture, Lorestan University to find (Cicerarietinum L) water requirement and different crop coefficients. Therefore, 4 drainable lysimeter was selected with diameter of 0.45 m and height of 0.8 m. The crop density was 50 plant per m^2, than by using of water balance model, the actual evapotranspiration was estimated. The 〖ET〗_cof Chickpea in the year of study was 438.04 mm. The potential evapotranspiration also was estimated by lysimeter. The value was obtained equal 550.20 mm. Finally, the crop coefficient for initial, development, middle and late season of Chickpea were estimated as 0.488, 0.955, 1.083 and 0.371.

The objective of this study was to evaluate how the design and the management of solid set sprinkle irrigation systems in Koohdasht plain of Loreistan province. For this purpose, 10 solid-set sprinkle irrigation systems were evaluated .For evaluating of the selected systems, some performance indicators were used such as Christiansen’s coefficient of uniformity(CU), distribution uniformity(DU), potential application efficiency of low-quarter (PELQ), application efficiency of low-quarter(AELQ), wind drift and evaporation losses(WDEL), deep percolation losses(DP) and adequacy of irrigation(ADirr). The mean values of these parameters were obtained 70.84, 43.64, 46.85, 38.01, 8.77, 31.02 and 64.66%, respectively. All of systems have low PELQ values and also water distribution uniformity of them were lower than recommended values by Merriam and Keller. In 4 systems out of 10 systems, irrigation is complete and deficit irrigation occurred in the other systems so AELQ values were equal to PELQ. Unsuitable design and implementation of the systems were recognized as the most important reason of low PELQ. Synchronic utilization of many sprinklers and using rather than one sprinkler on lateral also were the most important reasons for low water distribution uniformity. In general, the results of this study showed that however in many of cases the design and executive problems were exist; but, a big share of the reason of low performance of sprinkle irrigation systems in koohdasht plain are the weak managing and operation of the systemsThe objective of this study was to evaluate how the design and the management of solid set sprinkle irrigation systems in Koohdasht plain of Loreistan province. For this purpose, 10 solid-set sprinkle irrigation systems were evaluated .For evaluating of the selected systems, some performance indicators were used such as Christiansen’s coefficient of uniformity(CU), distribution uniformity(DU), potential application efficiency of low-quarter (PELQ), application efficiency of low-quarter(AELQ), wind drift and evaporation losses(WDEL), deep percolation losses(DP) and adequacy of irrigation(ADirr). The mean values of these parameters were obtained 70.84, 43.64, 46.85, 38.01, 8.77, 31.02 and 64.66%, respectively. All of systems have low PELQ values and also water distribution uniformity of them were lower than recommended values by Merriam and Keller. In 4 systems out of 10 systems, irrigation is complete and deficit irrigation occurred in the other systems so AELQ values were equal to PELQ. Unsuitable design and implementation of the systems were recognized as the most important reason of low PELQ. Synchronic utilization of many sprinklers and using rather than one sprinkler on lateral also were the most important reasons for low water distribution uniformity. In general, the results of this study showed that however in many of cases the design and executive problems were exist; but, a big share of the reason of low performance of sprinkle irrigation systems in koohdasht plain are the weak managing and operation of the systemsThe objective of this study was to evaluate how the design and the management of solid set sprinkle irrigation systems in Koohdasht plain of Loreistan province. For this purpose, 10 solid-set sprinkle irrigation systems were evaluated .For evaluating of the selected systems, some performance indicators were used such as Christiansen’s coefficient of uniformity(CU), distribution uniformity(DU), potential application efficiency of low-quarter (PELQ), application efficiency of low-quarter(AELQ), wind drift and evaporation losses(WDEL), deep percolation losses(DP) and adequacy of irrigation(ADirr). The mean values of these parameters were obtained 70.84, 43.64, 46.85, 38.01, 8.77, 31.02 and 64.66%, respectively. All of systems have low PELQ values and also water distribution uniformity of them were lower than recommended values by Merriam and Keller. In 4 systems out of 10 systems, irrigation is complete and deficit irrigation occurred in the other systems so AELQ values were equal to PELQ. Unsuitable design and implementation of the systems were recognized as the most important reason of low PELQ. Synchronic utilization of many sprinklers and using rather than one sprinkler on lateral also were the most important reasons for low water distribution uniformity. In general, the results of this study showed that however in many of cases the design and executive problems were exist; but, a big share of the reason of low performance of sprinkle irrigation systems in koohdasht plain are the weak managing and operation of the systems of the systemsof the systemsof the systemsof the systemsof the systemsof the systems.

Mountainous area has a considerable share in supplying water demand in the arid regions. Because, snow consists a large part of the rainfall in such regions which could be saved in the area located in the high elevations for a long time. Therefore, snowmelt runoff consists a large part of the total runoff in the mountain watersheds. The snow hydrology is much complicated than rainfall hydrology since there is always a lag time in occurring snowmelt runoff in the basin's outlet. Thus, finding out simple methods for calculating such runoff is so much important. In this research, after calibrating and validating the critical temperature and degree-days coefficient, the HEC-HMS model was applied to simulate the snowmelt runoff in Karoun basin, which is one of the most important mountain watersheds in Iran.
In this research, a large part of Karoun watershed upto PolShaloo outlet was selected. This region is located in the southern-west of Iran which lies between 50o23'37" to 51o54'29" E longitude and between 30o16'50.4" to 31o32'18.3" N latitude. About 50 percentage of total precipitation rains as snow and usually occurs during November-May. HEC-HMS model was applied for runoff simulation. In this regard, first the whole basin was divided to eight sub-basins enttled Marghak, Barez, Pataveh, Kata, Solegkan, Armand, DazakAbad and PolShalou. Then, based on the Digital Elevation Mode, the sub-basin's physiographic characteristics were extracted in Arc-View environment and using HEC-GeoHMS extension. The values of curve number, lag time and initial loss was calibrated and validated for each of the sub-basins using the observed sonw-free runoff events. Thereafter, the hypsometric maps with 100-meter elevation intervals was prepared by which the area, the required thermal data, and snowmelt pattern was determined for each of the elevation bands. Moreover, the snow water equivalent was calculated in the first day of the selected snowy events based on the daily calculations of snowmelt. After providing the required input data, the HEC-HMS mode was run for the snowy events and the critical temperature and degree-day coefficient was calibrated and validated for the study area.
The hypsometric maps with 100-meter elevation intervals revealed that 22, 70 and 8 percentage of the study area is, respectively, located in area with the elevations ranges of 693-2000, 2000-3000 and >3000 meter. Based on the observed data in the snow survey stations in the study area, the correlation coefficient between snow water equivalent and elevations was higher than 90 percentage. Therefore, this equation was applied for determining the snow water equivalent in the beginning of the selected snowy events. The daily calculations of snowmelt based on this equation showed that in Mach 17, 1998, which is the first day of the first selected snowy event, all the regions with elevations higher than 1943 meter is covered by snow and the non-snow regions covers less than 20 percentage of the study area. The results of the sensitivity analysis of the HEC-HMS model for calibrating the basin's physiographic parameters in the non-snow events revealed that the curve number, initial loss and lag time parameters had the most effect on the outlet discharge. The calibrated values for these parameters ranges among 76.6-91, 5.02-13.96 millimeter and 155-571.12 minutes, respectively. After calibrating and validating the basin's physiographic parameters, the snowmelt parameters were calibrated and validated base on the observed runoff during March 17-19, 1998, which is one of the largest snowy event in the study area. In this stage, the results of the sensitivity analysis demonstrated that critical temperature and degree-day coefficient had the most effect on three characteristics of flood hydrograph including the peak discharge, the average flood depth and the time of peak discharge occurrence. The increase in the critical temperature usually led to the peak runoff delaying. Except was for Armand sub-basin due to its high area in which, the increase in the critical temperature, the peak discharge of the flood hydrograph was increased mainly due to increasing the snow melt rate and the flow rate. The best values for critical temperature and degree-day coefficient was obtained, respectively, 2.5 oC and 3.2 millimeter per oC-day through the calibration process. Based on the calculated criteria indices in the validation process, applying these values led to the acceptable erors in estimating snowmelt runoff for the flood event occurred through March 25, 1998 to April 8, 1998.
Conclusions and Recommendations: Results of this research showed that among different physiographic characteristics, the curve number, initial loss and lag time parameters had the most effect on the average flood depth, the peak discharge and the time to the peak discharge for the non-snow events. Moreover, the snowmelt runoff is highly influenced by critical temperature and degree-day coefficient and therefore, the HEC-HMs results for simulating runoff in the mountain watersheds will be reliable if the suitable values are selected for these parameters. Based on the results of this study, 2.5oC and 3.2 millimeter per degree-days will be, respectively, the best values for critical temperature and degree-day coefficient in the study area and these values could be used in the further researches in Karoun Basin.

The streams can be divided into 3 groups; 1) Perennial Streams, 2) Seasonal Streams and 3) Ephemeral Streams. Seasonal streams are the kinds of stream that have flowed in certain seasons and they often occur in the watershed due to snow melt or sudden rain. The flow in this type of streams, acts as a flash flood, consequently its flow hydrograph has a sharp peak and a relatively short base time and it can cause erosion and sediment transport in the watershed, which altogether create some problems and constraints to human. The purpose of this research is measuring the temporal changes of sediment transported (bed-load) by flash flood (unsteady flow condition) in laboratory flume. The experiment canal that use in this research has 10 m length, 30 cm width, and 50 cm height. Using an electrical device which is connected to the channel pump, input flow turns into an unsteady flow and then enters the channel. Some of the characteristics of this flow are imperceptible increase and decrease while passing through laboratory flume. In this research, a new method is also presented for sampling and measuring the bed load sediment which is transported by the flow in laboratory. In this method form of canal is changed. We created five section. 1) Fixed roughness, 2) mobile bed load, 3) section of sampling, 4) Fixed roughness and 5) glass. The sampler of sediment include 20 net box with length, width and height 25 cm, 5 cm and 3 cm Respectively. For inscription date, use two camera system. One of them for record of bed change that set in front of mobile bed and another one for record boxes of sampler movement under the section of sampling. Time duration of sampling for each box of sampler is between 3 to 6 second. A grading of sediment with D50=2.5 mm is used. This research includes a series of stream symmetric triangular hydrographs in different shapes and contains different base time (60 sec , 90 sec , and 120 sec) and peak flow (between 20 and 55 liter per second), which were crossed from the bed of sediment then the transported bed load, affected by them, was removed by using the produced sampler. Also as bases flow, two steady stream 0.95 and 1.5 liter per second is determined. The effect of some factors such as existence or lack of the base flow on amount of transported bed load were also checked and experimented by input stream hydrograph. The results show that maximum transmission sediment bed load decrease with stream of base flow and it is minimum at experiment without base flow. Also total of sediment transport is higher in experiment with base flow. Therefor exist of the base flow can increase sediment transport and upstream erosion. In this experiment the result show that occur the hydrograph with elder base flow, increase upstream erosion to 76.5 % and for another base flow they increase 26.5 %. For hydrograph with the same pick flow, when its base time, increase 1.5 and 2 times, total sediment transport increase 45 and 92 percent. Also peak of sedigraph increase with base time and therefor base time is an important parameter for upstream erosion and sediment transport. Another part of this research also checked the effects of fixed bed roughness on characteristics of flow hydrographic in a channel. In this series of experiments, the fixed bed was made using three different roughness’s including one roughness of glass and two roughness’s of different granulations. The results of movable bed show that bed slope has a great effect on upstream erosion and transportation of sediment to downstream. Since increases the bed slope from 0.005 to 0.01 increased 50% bed load transported and with two times the slope it show increase 400% in bed load transported also the results show that a temporal lag was found between the flow hydrographs peak and the sediment hydrograph peak. The temporal lag was found to be about equal to 5 - 11% of flow hydrograph duration. For hydrograph with the same pick flow, sediment transport average decrease with increase base time. Also elevation of bed load shown that maximum erosion occurs at the start of bed load.

This study aimed to derive the daily air temperature disaggregation parameters for some regions of Iran and to compare the performance of some daily-to-subdaily air temperature disaggregation Models. For this purpose, air temperature disaggregation models, including WAVE I, WAVE II, WCALC, ERBS, ESRA, and TM models were calibrated and their performance were compared, using long-term daily and three-hourly weather data obtained from 12 different synoptic weather stations in Iran. The results indicated that compared to the WAVE I, WAVE II, WCALC, ERBS, and ESRA models, the calibrated TM model had the best performance to disaggregate daily air temperature with a model efficiency (EF) of 0.9770 to 0.9877. Compared to air temperature disaggregation models with an arbitrary value for the time of maximum and minimum air temperature, the models in which the above mentioned times are described as a function of sunrise and/or sunset had better performance in describing the diurnal variations in air temperature. The use of the WAVE II model can be recommended for the regions with no subdaily weather data needed for calibration of the disaggregation models.This study aimed to derive the daily air temperature disaggregation parameters for some regions of Iran and to compare the performance of some daily-to-subdaily air temperature disaggregation Models. For this purpose, air temperature disaggregation models, including WAVE I, WAVE II, WCALC, ERBS, ESRA, and TM models were calibrated and their performance were compared, using long-term daily and three-hourly weather data obtained from 12 different synoptic weather stations in Iran. The results indicated that compared to the WAVE I, WAVE II, WCALC, ERBS, and ESRA models, the calibrated TM model had the best performance to disaggregate daily air temperature with a model efficiency (EF) of 0.9770 to 0.9877. Compared to air temperature disaggregation models with an arbitrary value for the time of maximum and minimum air temperature, the models in which the above mentioned times are described as a function of sunrise and/or sunset had better performance in describing the diurnal variations in air temperature. The use of the WAVE II model can be recommended for the regions with no subdaily weather data needed for calibration of the disaggregation models.This study aimed to derive the daily air temperature disaggregation parameters for some regions of Iran and to compare the performance of some daily-to-subdaily air temperature disaggregation Models. For this purpose, air temperature disaggregation models, including WAVE I, WAVE II, WCALC, ERBS, ESRA, and TM models were calibrated and their performance were compared, using long-term daily and three-hourly weather data obtained from 12 different synoptic weather stations in Iran. The results indicated that compared to the WAVE I, WAVE II, WCALC, ERBS, and ESRA models, the calibrated TM model had the best performance to disaggregate daily air temperature with a model efficiency (EF) of 0.9770 to 0.9877. Compared to air temperature disaggregation models with an arbitrary value for the time of maximum and minimum air temperature, the models in which the above mentioned times are described as a function of sunrise and/or sunset had better performance in describing the diurnal variations in air temperature. The use of the WAVE II model can be recommended for the regions with no subdaily weather data needed for calibration of the disaggregation models.This study aimed to derive the daily air temperature disaggregation parameters for some regions of Iran and to compare the performance of some daily-to-subdaily air temperature disaggregation Models. For this purpose, air temperature disaggregation models, including WAVE I, WAVE II, WCALC, ERBS, ESRA, and TM models were calibrated and their performance were compared, using long-term daily and three-hourly weather data obtained from 12 different synoptic weather stations in Iran. The results indicated that compared to the WAVE I, WAVE II, WCALC, ERBS, and ESRA models, the calibrated TM model had the best performance to disaggregate daily air temperature with a model efficiency (EF) of 0.9770 to 0.9877. Compared to air temperature disaggregation models with an arbitrary value for the time of maximum and minimum air temperature, the models in which the above mentioned times are described as a function of sunrise and/or sunset had better performance in describing the diurnal variations in air temperature. The use of the WAVE II model can be recommended for the regions with no subdaily weather data needed for calibration of the disaggregation models.This study aimed to derive the daily air temperature disaggregation parameters for some regions of Iran and to compare the performance of some daily-to-subdaily air temperature disaggregation Models. For this purpose, air temperature disaggregation models, including WAVE I, WAVE II, WCALC, ERBS, ESRA, and TM models were calibrated and their performance were compared, using long-term daily and three-hourly weather data obtained from 12 different synoptic weather stations in Iran. The results indicated that compared to the WAVE I, WAVE II, WCALC, ERBS, and ESRA models, the calibrated TM model had the best performance to disaggregate daily air temperature with a model efficiency (EF) of 0.9770 to 0.9877. Compared to air temperature disaggregation models with an arbitrary value for the time of maximum and minimum air temperature, the models in which the above mentioned times are described as a function of sunrise and/or sunset had better performance in describing the diurnal variations in air temperature. The use of the WAVE II model can be recommended for the regions with no subdaily weather data needed for calibration of the disaggregation models.

Drought phenomenon has significant effects on various aspects, especially in the arid and semiarid regions of Iran like as Yazd province. Drought condition in an area has been evaluated using conventional indices. This research attempts to select an efficient index with regional applicability. According to related literature, appropriate index has been selected based on the objects and type of study. In this research, SPI has been identified as an appropriate index for study of groundwater condition during drought. Hence, different time scales of SPI were applied to check correlation between SPI and fluctuation of the water table in the study area. The results show high correlation between fluctuations of the water table in piezometers with SPI 12-month period. As a result, SPI 12-month is proposed as appropriate drought index in the study area.Drought phenomenon has significant effects on various aspects, especially in the arid and semiarid regions of Iran like as Yazd province. Drought condition in an area has been evaluated using conventional indices. This research attempts to select an efficient index with regional applicability. According to related literature, appropriate index has been selected based on the objects and type of study. In this research, SPI has been identified as an appropriate index for study of groundwater condition during drought. Hence, different time scales of SPI were applied to check correlation between SPI and fluctuation of the water table in the study area. The results show high correlation between fluctuations of the water table in piezometers with SPI 12-month period. As a result, SPI 12-month is proposed as appropriate drought index in the study area.Drought phenomenon has significant effects on various aspects, especially in the arid and semiarid regions of Iran like as Yazd province. Drought condition in an area has been evaluated using conventional indices. This research attempts to select an efficient index with regional applicability. According to related literature, appropriate index has been selected based on the objects and type of study. In this research, SPI has been identified as an appropriate index for study of groundwater condition during drought. Hence, different time scales of SPI were applied to check correlation between SPI and fluctuation of the water table in the study area. The results show high correlation between fluctuations of the water table in piezometers with SPI 12-month period. As a result, SPI 12-month is proposed as appropriate drought index in the study area.Drought phenomenon has significant effects on various aspects, especially in the arid and semiarid regions of Iran like as Yazd province. Drought condition in an area has been evaluated using conventional indices. This research attempts to select an efficient index with regional applicability. According to related literature, appropriate index has been selected based on the objects and type of study. In this research, SPI has been identified as an appropriate index for study of groundwater condition during drought. Hence, different time scales of SPI were applied to check correlation between SPI and fluctuation of the water table in the study area. The results show high correlation between fluctuations of the water table in piezometers with SPI 12-month period. As a result, SPI 12-month is proposed as appropriate drought index in the study area.Drought phenomenon has significant effects on various aspects, especially in the arid and semiarid regions of Iran like as Yazd province. Drought condition in an area has been evaluated using conventional indices. This research attempts to select an efficient index with regional applicability. According to related literature, appropriate index has been selected based on the objects and type of study. In this research, SPI has been identified as an appropriate index for study of groundwater condition during drought. Hence, different time scales of SPI were applied to check correlation between SPI and fluctuation of the water table in the study area. The results show high correlation between fluctuations of the water table in piezometers with SPI 12-month period. As a result, SPI 12-month is proposed as appropriate drought index in the study area.Drought phenomenon has significant effects on various aspects, especially in the arid and semiarid regions of Iran like as Yazd province. Drought condition in an area has been evaluated using conventional indices. This research attempts to select an efficient index with regional applicability. According to related literature, appropriate index has been selected based on the objects and type of study. In this research, SPI has been identified as an appropriate index for study of groundwater condition during drought. Hence, different time scales of SPI were applied to check correlation between SPI and fluctuation of the water table in the study area. The results show high correlation between fluctuations of the water table in piezometers with SPI 12-month period. As a result, SPI 12-month is proposed as appropriate drought index in the study area.

Surface temperature maps are the most important components of the water requirements in basin scale and also are the most difficult to measure. Conventional methods are very local, ranging from region to field scale. Estimates of the Surface temperature and crop density over the entire area, especially for irrigated areas, are essential. Today, surface temperature can be estimated by using satellites and remote sensing (RS) techniques. In order to obtain the surface temperature, a set of satellite images was used. From a set of 12 Landsat 7 images during the 1998-2002, NDVI and SAVI indicators were established. Based on these indicators the surface temperature was estimated using the SEBAL (surface energy balance algorithm for land) algorithm and compared by measured data that reported by meteorological stations in Hamedan province. Results indicated that, no significant difference between surface temperature using remote sensing data and that reported by meteorological stations. Primary results showed that there was a significant relationship between measured and estimated surface temperature. The results of correlation coefficient were 0.75 and Root Mean Square Error (RMSE) was 5.4 c○, respectively.Surface temperature maps are the most important components of the water requirements in basin scale and also are the most difficult to measure. Conventional methods are very local, ranging from region to field scale. Estimates of the Surface temperature and crop density over the entire area, especially for irrigated areas, are essential. Today, surface temperature can be estimated by using satellites and remote sensing (RS) techniques. In order to obtain the surface temperature, a set of satellite images was used. From a set of 12 Landsat 7 images during the 1998-2002, NDVI and SAVI indicators were established. Based on these indicators the surface temperature was estimated using the SEBAL (surface energy balance algorithm for land) algorithm and compared by measured data that reported by meteorological stations in Hamedan province. Results indicated that, no significant difference between surface temperature using remote sensing data and that reported by meteorological stations. Primary results showed that there was a significant relationship between measured and estimated surface temperature. The results of correlation coefficient were 0.75 and Root Mean Square Error (RMSE) was 5.4 c○, respectively.Surface temperature maps are the most important components of the water requirements in basin scale and also are the most difficult to measure. Conventional methods are very local, ranging from region to field scale. Estimates of the Surface temperature and crop density over the entire area, especially for irrigated areas, are essential. Today, surface temperature can be estimated by using satellites and remote sensing (RS) techniques. In order to obtain the surface temperature, a set of satellite images was used. From a set of 12 Landsat 7 images during the 1998-2002, NDVI and SAVI indicators were established. Based on these indicators the surface temperature was estimated using the SEBAL (surface energy balance algorithm for land) algorithm and compared by measured data that reported by meteorological stations in Hamedan province. Results indicated that, no significant difference between surface temperature using remote sensing data and that reported by meteorological stations. Primary results showed that there was a significant relationship between measured and estimated surface temperature. The results of correlation coefficient were 0.75 and Root Mean Square Error (RMSE) was 5.4 c○, respectively.Surface temperature maps are the most important components of the water requirements in basin scale and also are the most difficult to measure. Conventional methods are very local, ranging from region to field scale. Estimates of the Surface temperature and crop density over the entire area, especially for irrigated areas, are essential. Today, surface temperature can be estimated by using satellites and remote sensing (RS) techniques. In order to obtain the surface temperature, a set of satellite images was used. From a set of 12 Landsat 7 images during the 1998-2002, NDVI and SAVI indicators were established. Based on these indicators the surface temperature was estimated using the SEBAL (surface energy balance algorithm for land) algorithm and compared by measured data that reported by meteorological stations in Hamedan province. Results indicated that, no significant difference between surface temperature using remote sensing data and that reported by meteorological stations. Primary results showed that there was a significant relationship between measured and estimated surface temperature. The results of correlation coefficient were 0.75 and Root Mean Square Error (RMSE) was 5.4 c○, respectively.

Agricultural development in Iran depends on the amount of water and knowledge of the seepage from canals is required. Although there are many empirical equations for estimating canal seepage, the coefficients of these equations are different from Iranian conditions and these equations vary in different areas. In this research, the ability of the Seep/w model was studied to estimate the seepage from an assumed canal. Variable parameters are normal depth in canal and hydraulic conductivity of soil. In addition, hydraulic gradient, uplift pressure and seepage velocity are investigated in canal. Results show that with decreasing in canal slope, seepage discharge linearly increased. Minimum hydraulic gradient and seepage velocity is in center line of canal. Increasing of hydraulic conductivity, causes to increase seepage discharge linearly. Agricultural development in Iran depends on the amount of water and knowledge of the seepage from canals is required. Although there are many empirical equations for estimating canal seepage, the coefficients of these equations are different from Iranian conditions and these equations vary in different areas. In this research, the ability of the Seep/w model was studied to estimate the seepage from an assumed canal. Variable parameters are normal depth in canal and hydraulic conductivity of soil. In addition, hydraulic gradient, uplift pressure and seepage velocity are investigated in canal. Results show that with decreasing in canal slope, seepage discharge linearly increased. Minimum hydraulic gradient and seepage velocity is in center line of canal. Increasing of hydraulic conductivity, causes to increase seepage discharge linearly. Agricultural development in Iran depends on the amount of water and knowledge of the seepage from canals is required. Although there are many empirical equations for estimating canal seepage, the coefficients of these equations are different from Iranian conditions and these equations vary in different areas. In this research, the ability of the Seep/w model was studied to estimate the seepage from an assumed canal. Variable parameters are normal depth in canal and hydraulic conductivity of soil. In addition, hydraulic gradient, uplift pressure and seepage velocity are investigated in canal. Results show that with decreasing in canal slope, seepage discharge linearly increased. Minimum hydraulic gradient and seepage velocity is in center line of canal. Increasing of hydraulic conductivity, causes to increase seepage discharge linearly. Agricultural development in Iran depends on the amount of water and knowledge of the seepage from canals is required. Although there are many empirical equations for estimating canal seepage, the coefficients of these equations are different from Iranian conditions and these equations vary in different areas. In this research, the ability of the Seep/w model was studied to estimate the seepage from an assumed canal. Variable parameters are normal depth in canal and hydraulic conductivity of soil. In addition, hydraulic gradient, uplift pressure and seepage velocity are investigated in canal. Results show that with decreasing in canal slope, seepage discharge linearly increased. Minimum hydraulic gradient and seepage velocity is in center line of canal. Increasing of hydraulic conductivity, causes to increase seepage discharge linearly. Agricultural development in Iran depends on the amount of water and knowledge of the seepage from canals is required. Although there are many empirical equations for estimating canal seepage, the coefficients of these equations are different from Iranian conditions and these equations vary in different areas. In this research, the ability of the Seep/w model was studied to estimate the seepage from an assumed canal. Variable parameters are normal depth in canal and hydraulic conductivity of soil. In addition, hydraulic gradient, uplift pressure and seepage velocity are investigated in canal. Results show that with decreasing in canal slope, seepage discharge linearly increased. Minimum hydraulic gradient and seepage velocity is in center line of canal. Increasing of hydraulic conductivity, causes to increase seepage discharge linearly. Agricultural development in Iran depends on the amount of water and knowledge of the seepage from canals is required. Although there are many empirical equations for estimating canal seepage, the coefficients of these equations are different from Iranian conditions and these equations vary in different areas. In this research, the ability of the Seep/w model was studied to estimate the seepage from an assumed canal. Variable parameters are normal depth in canal and hydraulic conductivity of soil. In addition, hydraulic gradient, uplift pressure and seepage velocity are investigated in canal. Results show that with decreasing in canal slope, seepage discharge linearly increased. Minimum hydraulic gradient and seepage velocity is in center line of canal. Increasing of hydraulic conductivity, causes to increase seepage discharge linearly.

In This study using CCHE2D, to simulate flow and sediment transport pattern meandering river reachlocated in the downstream of the Minab dam (Hormozgan province, Iran). First, the geometry model and after that a numerical mesh systemwere calculated using the topographic surveysof the study area. Second, the required parameters for running CCHE2D were collected through field works. Finally, the model outputs including flow depth and velocity and changes in suspended load and bed sediment were obtained for the considered riverreach. In the end, the two statistical criteria RMSE and MAPE, the data obtained from numerical simulation model against observational data were compared. Model error parameters, RMSE of velocity, depth and energy slope, respectively, 0.075, 0.116 and 0.0008 and the index of MAPE respectively, 2.7, 6.2 and 4.4 percent. The results comparison indicated that the simulated values matched well with the field measurements.
In This study using CCHE2D, to simulate flow and sediment transport pattern meandering river reachlocated in the downstream of the Minab dam (Hormozgan province, Iran). First, the geometry model and after that a numerical mesh systemwere calculated using the topographic surveysof the study area. Second, the required parameters for running CCHE2D were collected through field works. Finally, the model outputs including flow depth and velocity and changes in suspended load and bed sediment were obtained for the considered riverreach. In the end, the two statistical criteria RMSE and MAPE, the data obtained from numerical simulation model against observational data were compared. Model error parameters, RMSE of velocity, depth and energy slope, respectively, 0.075, 0.116 and 0.0008 and the index of MAPE respectively, 2.7, 6.2 and 4.4 percent. The results comparison indicated that the simulated values matched well with the field measurements.
In This study using CCHE2D, to simulate flow and sediment transport pattern meandering river reachlocated in the downstream of the Minab dam (Hormozgan province, Iran). First, the geometry model and after that a numerical mesh systemwere calculated using the topographic surveysof the study area. Second, the required parameters for running CCHE2D were collected through field works. Finally, the model outputs including flow depth and velocity and changes in suspended load and bed sediment were obtained for the considered riverreach. In the end, the two statistical criteria RMSE and MAPE, the data obtained from numerical simulation model against observational data were compared. Model error parameters, RMSE of velocity, depth and energy slope, respectively, 0.075, 0.116 and 0.0008 and the index of MAPE respectively, 2.7, 6.2 and 4.4 percent. The results comparison indicated that the simulated values matched well with the field measurements.
In This study using CCHE2D, to simulate flow and sediment transport pattern meandering river reachlocated in the downstream of the Minab dam (Hormozgan province, Iran). First, the geometry model and after that a numerical mesh systemwere calculated using the topographic surveysof the study area. Second, the required parameters for running CCHE2D were collected through field works. Finally, the model outputs including flow depth and velocity and changes in suspended load and bed sediment were obtained for the considered riverreach. In the end, the two statistical criteria RMSE and MAPE, the data obtained from numerical simulation model against observational data were compared. Model error parameters, RMSE of velocity, depth and energy slope, respectively, 0.075, 0.116 and 0.0008 and the index of MAPE respectively, 2.7, 6.2 and 4.4 percent. The results comparison indicated that the simulated values matched well with the field measurements.
In This study using CCHE2D, to simulate flow and sediment transport pattern meandering river reachlocated in the downstream of the Minab dam (Hormozgan province, Iran). First, the geometry model and after that a numerical mesh systemwere calculated using the topographic surveysof the study area. Second, the required parameters for running CCHE2D were collected through field works. Finally, the model outputs including flow depth and velocity and changes in suspended load and bed sediment were obtained for the considered riverreach. In the end, the two statistical criteria RMSE and MAPE, the data obtained from numerical simulation model against observational data were compared. Model error parameters, RMSE of velocity, depth and energy slope, respectively, 0.075, 0.116 and 0.0008 and the index of MAPE respectively, 2.7, 6.2 and 4.4 percent. The results comparison indicated that the simulated values matched well with the field measurements.