Journal of Irrigation and Water Engineering
Year:2016 | Volume:6 | Issue:24|Papers Count:12

The indirect variables such as bed particles diameters could be applied to estimate roughness coefficients (RC) to decrease measurement costs. Bed particles diameters based relations were developed for non-vegetated channels. Therefore, the current study was conducted to evaluate bed particles diameters based relations (BPBR), to estimate roughness coefficients in vegetated canals for irrigation and drainage network of Moghan (in North-west of Iran) and to compare acquired RC from BPBR and RC from experiments and to model roughness coefficients in vegetated canals as a function of bed particles diameters. In irrigation and drainage network of Moghan 181 canals sections were selected to measure water flow velocity (with a flow meter) and canal cross sections. The Manning coefficients were estimated via water velocities, hydraulic radius and canal slopes. Results revealed that RC varied from 0.005 to 0.41 and averaged at 0.076 in vegetated channels. Also, Applying Strickler, Henderson, Garde and Raju and Bray (relations based on D50) and Ravdkivi, Bray, Lane and Carlson and Henderson (relations based on D65 and D75) did not produce a suitable value for RC in vegetated channels. The particle diameters (D50, D65 and D75) were applied to model roughness coefficient as a function of bed particles diameters in vegetated channels. Relative to the results from developed relations, the model results were relatively precision and recommendable. The correlation coefficient of RC with the particle diameters of D50, D65 and D75 were 0.91, 0.83 and 0.66, respectively. The advantages of developed models were accuracy, simplicity and facility in application.

Estimation of the suspended sediment load plays a very important role in water projects such as dam and surface water storage design, pollution and sediment transport in rivers and lakes, as well as design and maintenance the channels. The accuracy of conventional methods of sediment estimation, usually low and there are a big difference between their results. Therefore, in this study after preparing sediment and flow discharge data of hydrometric stations; Jow Kanak, Behbahan, Shadegan, Moshrageh and Cham Nezam, the M5 algorithm, has been used to determine the suspended sediment load. M5 tree algorithm is one of the newest data-driven models which divides the problem space into multiple branches and proposes equations for each branches. Flow discharge of each day and the day before have been used as an input variables and sediment discharge has been considered as an output variable to build and validate the tree model. Statistical analysis on tree model showed better compliance of tree model results with observed data in compare with sediment rating curve method. RMSE for training and validation phases at studied stations were 0.59 and 0.74 for M5 and rating curve methods, respectively. The results of this study showed that suspended sediment load could be accurately predicted using M5 tree algorithm. The results of this model, in addition to have an understandable and simple structure, could be used in practical issues as well.

Paddy fields development and renovation as the most important project to improve infrastructures of the rice sustainable production in North of Iran have had very slow Implementation pace due to various reasons and so that the project has been executed in less than 60000 hectares out of total paddy fields in Mazandaran province. Therefore, identification and prioritization of design, execution and operational problems is the basic requirements to change the existing situation. this research consider comparative comparison method between the design and as-built drawings, field monitoring of operating difficulties as well discussion and interview with experts. Then finalized list of problems, which used to develop a questionnaire with seven inquiries based on the Analytic Hierarchy Process (AHP). It containsfour main indicators employers’ arrangements, design, execution and finally, operation and maintenance. So, 35 experts of paddy fields Development and Renovation were selected (from Jihad-e-Agriculture Organization, consulting engineers and the contractors) to fill out the questionnaire. The results indicate the fundamental limitations in order of priority are: failure to provide the timely required credits, the lack of integrated viewpoint on irrigation and drainage studies, the lack of f operational organizations same as agricultural NGOs, deficiencies in farmers training which needs for proper operation and maintenance of the projects and legal problems especially when private property is incompatible with the public profits. Therefore, serious offers of this research are change in the financing method of the projects, for example e use of combination of native and foreign countries finance, build of all layout components of project and use of other constructing project procedures such as EPC (Engineering Procurement Construction).

Field capacity (FC) and permanent wilting point (PWP) are efficacious in determining net irrigation water depth. However, direct measurement of these properties is tedious, time consuming and costly especially on large scale. Soil pedotransfer functions (PTFs) as the indirect methods can replace by the direct methods. In this study, performance of the six available pedotransfer functions on FC and PWP moisture content predicting was evaluated on 112 soil samples that were collected from the north and northeast regions of Iran. The Root Mean Square Error (RMSE) values of menioned available PTFs were changed between 0.05 to 0.17 and 0.03 to 0.13 in moisture prediction on FC and PWP points, respectively. Therefore new PTFs were developed by Multiple Linear Regression (MLR) and Artificial Neural Network (ANN) techniques based on soil properties (90 samples) and the results were validated on different soils (22 samples). The results showed that both MLR technique with assigning the RMSE values approximately 0.035, 0.01, 0.027 and 0.024 to predict soil moisture content on FC and PWP, total available water and specific yield and ANN technique with assigning the values approximately 0.013, 0.007, 0.015 and 0.013 to the same properties, evaluated in appropriate performance. The results also showed that using variables such as geometric mean and geometric standard deviation particle diameter, fractal dimension and air-entry suction, for the first one on input variables of PTFs, improved the accuracy of the results significantly, although accepting of this theory requires more studies.

Urmia Lake in Iran is the second largest saline lake in the world. Due to various socio-economical and ecological criteria, Urmia Lake has important role in the Northwestern part of the country but it has faced many problems in recent years. Because of droughts, overuse of surface water resources and dam constructions water level is reduced. One of the important factors that has influence in correct management, is having a suitable point of view for future events in that field. So simulation and forecasting of hydrological variables has many importance. In this research, time series, Artificial Neural Network and Neural Network-Wavelet methods for presentation the best method in monthly scale for simulation and forecasting Urmia Lake water level is compared. Comparing these three methods indicates that forecasting with Neural Network-Wavelet due to considering monthly, seasonal and annual changes in the time series analysis, has the best Performance.

Soil salinity is one of the most important factor which causing a considerable decrease in crop productivity of pistachio orchards in Kerman. In this research, the effects of applying different amendments on reclamation of a saline calcareous soil was investigated by using experimental soil columns. Treatments included: a) irrigation water, b) irrigation water+gypsum mixed with soil surface, and c) dissolved gypsum as well as d) sulfuric acid application. Leaching was done intermittently and 2 pore volumes (PVs) were allowed to pass through the soil columns. Based on the results, no significant difference was observed in the concentration of cations as well as EC among different treatments. Application of 1.5 PVs of irrigation water, removed 60% of the total sodium, 70% of magnesium and 70% of soluble salts from the soil column. The cumulative leached Ca2+ caused by 2 PVs was very small, accounted for about 4 percentage of total content of Ca2+. Application of chemical amendments was not significant on infiltration rate as compared to irrigation water. In terms of water requirement for salt removal from 1 to 1.5 pore volumes, it is recommended that 1 pore volume of irrigation water which efficiently reduced soil sodium and magnesium concentration, soil EC and costs, is the suitable strategy for practical reclamation of the studied soil.

The present study aimed at investigating four different models to estimate pan evaporation coefficient (Kp) to measure alfalfa-reference evapotranspiration. To this end the values of pan coefficient obtained from Cuenca, Allen and Priutt, Snyder and Orang equations in Kerman with arid climate were calculated. Then, the values of alfalfa-reference evapotranspiration (ET0) were measured using pan evaporation daily data in a period of five months (from 23/07/2013 to 21/12/2013) on experimental farm of Shahid Bahonar University of Kerman. Based on the daily weather data provided by the automatic weather station in this farm (during the study), ET0 was calculated using ASCE standard Penman-Monteith model and was used as an index to measure alfalfa-reference evapotranspiration obtained from the four stated models. The results indicated that d-index in Allen and Priutt model was closer to 1 (0.823) with fewer errors compared to those of the other models (RMSE=1.607 and MAE=1.412). Accordingly, among the four models under investigation, Allen and Priutt is suggested to estimate evapotranspiration using pan evaporation in such a climate.

In this research, changes trend of quantity and quality of underground water and also trend of changes in drought in Fasa plain- Fars that is one of the most important population centers in Fars province evaluated. In order to this, data of 52 wells from plain in period 2006 to 2013 and precipitation data of Fasa station from 1967 to 2013 was used. To evaluate of data and assessment of time trend of them Aquachem and R softwares were used. Results of evaluation of changes trend in groundwater level showed that groundwater level has had decreasing trend in the recent two decades. So that average annual decline of water table level is about 0.95 meters per year. Results of evaluation of water quality changes in study period showed that the all quality parameters have had an increasing trend. Increasing trend of changes in Cl, Ca and TH in 90% level and in EC in 95% level are significant. This reflects that the quality of underground water has a decreasing trend. Evaluation of changes trend of drought showed that repetition of meteorological drought occurrence in recent decade (2003-2013) compared to the past four decades (1967- 2003) has been 2.5 times.

Groundwater is one of the main sources of drinking water supply, agriculture, and... in Birjand region, So the management of underground water table is very important. GMS software is one of the most prestigious models based on groundwater modeling that considered with steady and unsteady flow. This model is able to simulate and predict the future status of an aquifer with defined scenarios. The purpose of building a conceptual model is to simplify the field problem and organize the associated field data so that the system can be analyzed more readily. For Steady state September. month was selected that have less oscillation in water table, and for un-steady state October 80 to August 91 during 20 time steps were selected. After running the model, calibration and sensitivity analysis according to the underground water balance perform, and show that model is sensitive toward hydraulic conductivity and in unsteady state is sensitive toward specific yield. Based on balance equation the aquifer will have 10 meters shortage in water table in aquifer in 5 years prediction. In this model for predict quality in birjand plain used MT3D modules. In the model due to lack of quality parameters, in MT3D only Nitrate (No3) was investigated and the results indicate the correlation between water table and increasing in nitrate. During 5 years increase nitrate in lowering of birjand city and agriculture land.

Water quality determining in water resources evaluation is significantly important and its monitoring and zoning are key factors which should be considered in town planning. The aim of this study is identifying the most appropriate interpolation method for water quality determining by using Schuler and Will Cox diagrams in drink and agriculture sectors. Over this study, 22 piezometric wells are used in an unconfined aquifer located in Malayer plain. To determine the quality of drink and agriculture water, Schuler and Will Cox diagrams that are the most common classification methods are used respectively. Geostatistical methods that namely Kriging, Co-kriging and Inverse Distance Weighing (IDW) are used in GIS for water quality zoning in the study area and their results are compared to each other as well. The results showed that the simple Co-kriging technique (spherical) is the most appropriate interpolator for interpolating and zoning the drink and agriculture water quality. Investigation of drink water quality based on Schuler diagrams with considering TDS and TH parameters showed that the drink water quality is divided into three groups; good, acceptable and inappropriate. In the agriculture sector based on Will Cox diagrams using EC and SAR parameters, agriculture water quality is measured into two groups; good and average.

Determination of propitiate pollution indices is important for the design of wastewater refinery systems in small communities and rural area. This study aimed to determine the best indices of pollution for the design of wastewater refinery systems in small communities based on short-term data. For this purpose, wastewater samples were taken from Dehmilan, Hotkan, Sarbagh and Sekukan refineries in 10 replicates, each at one week interval. Different parameters including BOD, COD, TOC, EC, TSS, TDS, DO, TKN, TP, pH, Temp, Turb and Alk and also the concentrations of Cd, Zn, Pb, Ni and Mo were measured using the standard methods. Results showed that the amounts of BOD, COD, TOC, TSS, DO, pH, Temp, Turb, Cd and Pb differed significantly among the refining systems, whereas, significant differences (p<0.05) were found for the other measured parameters. Based on the statistical analysis, BOD, COD, TOC, TSS and Turb were selected as the most important indices for the planning of small communities refining systems. The values (±standard deviation) for the above mentioned indicators were 223.4±19.6, 466.8±42.4, 81.13±5.7, 158.6±19.3 and 123.4±14.2, respectively. Based on the findings of this study, the obtained values can be suggested for the planning of any other designing wastewater refining systems in rural societies which are similar in climate and culture.

Water shortages has always been a great concern as a limiting factor for agricultural production in Kerman province. Rainfed sowing may be recommended to bypass the problem. Because of high rates of potential evapotranspiration and limited water resources in arid and semiarid areas, it is expected more attention will be paid to study of the effects of rain fed culture on quality of medicinal plants. In order to investigate the establishment, growth and yield of some of perennial medicinal plants (Thymus caramanicus, Elaeagnus angustifolia, Olea europaeain, Thymus vulgaris, Rosa damascena, Thymus daenensis, Artemisia persica, Ferula assa feotida, Glycyrrhiza glabra, Rosmarinus officinalis, Lavandula officinalis, Salvia officinalis, Achillea millefolium), the study was conducted using a randomized complete block design (RCBD) with 3 replications during 3 years from 2012 to 2014 in the Kohpanj mountains in the west of Bardsir city. During the growing seasons, the phonological and morphological events were recorded and finally analyzed by SAS software and the means were compared using Duncan's Multiple Range Test at 0.05 level. The results showed Thymus caramanicus, Elaeagnus angustifolia and Olea europaeain destroyed in the first summer because of environmental drought. Thymus vulgaris, Rosmarinus officinalis, lavandula officinalis, Achillea millefolium and Salvia officinalis Survived in the first year, but destroyed in the second year. Rosa damascena (85%), Thymus daenensis (60%), Artemisia persica (77%), Ferula assa feotida (100%) and Glycyrrhiza glabra (100%) had the most survival rate among the species. With aging, dry weight of the plants were increased. The greatest dry weights were in Thymus daenensis, Artemisia persica and Ferula assa feotida respectively equal 188, 135.6 and 16 g/m2. The greatest dry weight of root in Glycyrrhiza glabra (173.3 g/m2) obtaind in the third year. The most number of flowers in Rosa damascena (31 flowers per plant) obtained in the third year.