مجله آبیاری و زهکشی ایران
سال سیزدهم شماره 1 (فروردین و اردیبهشت 1398)

The purpose of this study is to use a semi-distributed VIC model to estimate monthly runoff, actual evapotranspiration and soil moisture in the Neyshabour basin for the period of 1985 to 2014. Results of sensitivity analysis showed that in the mechanism of simulating runoff, the VIC model is more sensitive to infiltration capacity parameter and second soil layer. First, the VIC model was calibrated using a simulated runoff data comparison with the basin outlet for the years 1995-1993. The results indicate the high performance of the model in simulating the flow of the basin outlet. So that the values of R2 and NSE were 0.85 and 0.99, respectively. Also, the VIC model was verified with runoff data of Hossein Abad Jangal station and simulated evapotranspiration with SWAT and SEBAL algorithm. Values of R2 and NSE for runoff were 0.8 and 0.9. The results indicate that the simulated VIC model is more compatible with SWAT model data, and the values of R2 and NSE are 0.76 and 0.7, respectively. According to the obtained results, the VIC model can be used to simulate the variables required in water resources and meteorological studies.

The piano key weir is a developed version of nonlinear weirs with a very high discharge capacity. Due to the increase in effective length and consequently the increase in drainage efficiency of these weirs, they can be used in dam spillways or water regulation structures. This study aimed at the investigation of two-cycle piano key weir with a triangular nose. Several experiments have been conducted to determine the effect of geometric parameters of the input-to-output key widths (Wi/Wo( and the ratio of the weir’s length to the length of downstream slope (B/Bi) on the discharge coefficient. The results of this study showed that with increasing hydraulic load, the discharge coefficient was first increased and then reduced, and by increasing the input-to-output width ratios from 0.8 to 1.25, the discharge coefficient of piano key weir increased up to 26 percent. Using triangular nose has a positive effect on the discharge coefficient. In addition, the comparison with the results of other researchers showed that have the relationship developed in this study has less error than other relationships.

Fertigation is the application of fertilizers, soil amendments, or other water soluble products through an irrigation system. Fertigation can be applied for different kind of crops and horticultural plants as well as different types of irrigation systems, including surface and pressurized irrigation systems. Irrigated land in Golestan province is about 200000 hectares that most of them do not use fertigation system. So a research project has been done on the effectiveness of these systems on corn crop in two successive years 2007 and 2008. The experiment was laid out in a randomized complete design where each treatment was replicated three times. Two treatments were 200kg ha -1(N200) and 300 kg ha-1(N300) of pure nitrogen. Amount of considered urea fertilizers were applied through split application twice in two sprinkler and furrow irrigation systems separetly. Crop was SC704 sweet corn that is planted 75 to 20 cm intervals in July after wheat harvesting in the Gorgan agricultural station. During two years of testing, 8 and 7 times irrigation were applied respectively in which two of them accompanied by fertigation. Amount of irrigation water in the first year were 527 and 313 mm for furrow and sprinkler systems respectively and in the second year were 474 and 299 mm. Average grain yield that can be canned in the first year and N200 treatment were 3375 and 4072.3 kg ha-1 and in the second year, were 2637.3 and 4165.3 kg ha-1 for furrow and sprinkler systems respectively. Average grain yield that can be canned at treatment N300 in the first year were equal to 3124.3 and 2930.3 kg ha-1 and in the second year were 2647 and 3278.3 kg ha-1, for furrow and sprinkler systems respectively. The results showed that irrigation method had significant effect at 1% level on yield and yield components. The maximum values of grain yield 4165.3 kg ha-1 from N200 treatment in 2008, cob yield of 8795.6 kg ha-1 from N200 treatment in 200, biomass of 33184.6 kg ha-1 from N200 in 2007 and total dry matter of 7598.3 kg ha-1 from N200 in 2007 has been obtained from sprinkler irrigation that shows the effectiveness of sprinkler fertigation through ventory injector. Different nitrogen fertilizer rates had a significant effect on grain yield and total dry matter at 5% level and maximum grain yield and total dry matter production were obtained in N200 treatment. Different nitrogen fertilizer rates had no significant effect on cob and biomass. In general two years results indicate the effectiveness of fertilizer use efficiency in sprinkler fertigation.

Due to the importance of groundwater resources in arid and semi arid regions, the qualitative assessment of these resources is so important. Pressurized irrigation as a suitable method for increasing irrigation efficiency and reducing water consumption, requires water quality analysis. Despite many activities of researchers in the preparation of groundwater quality maps by using geostatistical methods, most of these studies have focused on the use of conventional kriging techniques that are not suitable for the preparation of vulnerable zones of contamination, In this study spatial variations of aquifer quality parameters and especially suitable areas for pressurized irrigation were investigated by using indicator Kriging method. For this purpose groundwater quality data from 27 wells in Birjand aquifer were studied during 2016. Qualitative parameters were evaluated including pH (acidity), EC (electrical conductivity), SAR (sodium absorption ratio), Na, NaCl, Cl and ClCO and HCO3, respectively. The allowed thresholds for use of these parameters were considered in pressurized irrigation with the proposed FAO limitaion. On the other hand, due to the importance of LangelierSaturation Index in sedimentation of drip irrigation system, this index was also evaluated for aquifer wells and unsuitable areas for pressurized irrigation in the aquifer were determined using the geostatistical indicator kriging method and ArcGIS software.The results indicate suitable irrigation region are located in the eastern and central parts of the plain.

In this study, Neural Network Technique is used to predict advance time using inflow rate, n coefficient, slope, length of furrow, infiltration curve number, initial soil moisture and bulk density by ANN and PCA Technique. Field measurements on furrows of different length and slopes in Mashhad, Dezful, Orumia, Birjand and Karaj having various soil Textures were used in this study. In the Training phase 144 advance time measured data were initially used and then 96 other field measurements were used for cross validation (48) and evaluation (48) phase. The enter parameters determined by using the sensitivity analysis Network and Principle Component Analysis (PCA) technique The obtained results showed Neural Network Technique is well capable of estimating advance Time with high accuracy. The best results (R2= 0.995) obtained from models that used of Principle Component Analysis as enter parameters. The models that used of initial soils moisture content (R2= 0.848) have higher accuracy in comparison to models that used of infiltration curve number (R2= 0.417) and Coefficient of Manning formula (R2= 0.492).

Marand plain is one of the most important regions for agricultural production in East Azarbaijan province, Iran. In this plain groundwater resources were applied to compensate more than 80% the water requirements of agricultural productions. Continuous consumption of groundwater caused a significant decline since 1982. Therefore, optimal and sustainable utilization of groundwater resources is a management necessity in Marand plain. Consequently, modeling and predicting the exploitation process could be accomplished by the appropriate techniques. This study was conducted with the aim of analyzing the groundwater level variations in Marand plain with time series models. Because of the ability of time series techniques to model and predict the behavior of temporal variation in water engineering phenomenon. Moreover, the groundwater level decline was modeled for 45-year with 14 methods of time series analysis in this study. An Autoregressive Integrated Moving Average (ARIMA) model was recognized as the most appropriate pattern. Modeling, testing and prediction were as follows: 25- year of the data for modeling (from 1982 to 2006), 10- year of data for the test (from 2006 to 2017) and future 10 years (from 2017 to 2027) were used for predicting ground water changes. Results showed that the average decline of groundwater from 1982 up to now was 17 m. For optimal management of groundwater application, different saving scenarios including 0, 5, 10, 15, 20, 25 and 30 percent savings starting from 2018 were considered. In the tenth year, about 67 ×106 m3 of groundwater will be saved with savings of only 10% from year of 2018. The land leveling, crop with low water requirements, deficit irrigation and irrigation scheduling could be applied to save groundwater in the north of Urmia Lake.

Considering the drought crisis and high consumption of water in paddy fields, it is useful to present strategies in order to increase irrigation efficiencies. However, one of the methods to increase productivity in the agricultural development of cropping and ratoon culture that has an important role in the economy of rural households. Therefore, it is necessary to determine the amount of water needed for the second cultivation of rice and the cultivation of ratoon for water resources planning. This study was conducted in Mazandaran province, Sari. The local Tarom early varieties during two crop seasons in 1395 and 1396 years of regional ratoon also was conducted in 1396. To measure the input and output flows, triangular overflow was applied to the treatments and three lysimeters were used to determine the water requirement of the fields. Water use efficiency and water productivity were investigated in each treatment season. The results showed that the highest consumption efficiency was measured at 61% in ratoon cultivation. The water use efficiency in ratoon cultivation increased by 39% compared with the second cultivation of 1395 and 42% compared to the second cultivation of 1396. Water productivity in the second cultivation of 1395 and 1396 and ratoon cultivation in 1396 was 51%, 33% and 40%, respectively. Therefore, in areas with enough rainfall during the second cultivation and cultivation of ratoon, second cultivation of rice and rattan culture can be recommended.

In the stepped spillway, the steps, by providing an artificial roughening bed, dissipate the flow of energy more than other types of spillways, which reduce the time and cost of constriction the dam and have been able to attract the designer's attention to these types of spillways. But what is important in this type of spillway, increasing the effectiveness of steps in the rate of energy dissipation. For this reason, the present study intends to consider the addition of wedge-shaped elements on the steps and its impact on the variation of the Darcy roughness, the height of the downstream water flow and, as a result, energy depletion on the stepped spillway. In this regard, first, several shapes of wedge elements are simulated with different layouts and arrangement using Flow-3D software and then by comparing the results, the proper model from aspect the most energy dissipation has been studied in the laboratory. Experiments were performed on 5 physical models, with changes in wedge layout and discharge rate, and the results were compared with simple stepped spillway. Numerical and experimental results show that the addition of wedge elements on the steps increases the Darcy roughness coefficient and reduces the height of water in the downstream of the spillway and as a result, the energy depletion increases significantly. By reducing the distance between the wedge elements, energy depreciation increases more significantly. Also, there are relationships between the Darcy roughness (f) and the ratio of the critical depth to the step roughness of the stairs (yc / k), that the high accuracy of these relationships (R2 = 0.9-0.98) indicate a significant dependence of the Darcy roughness (f) to the step roughness (k).

A hydraulic model of water distribution network is successful and reliable if it can simulate real condition by high accuracy. In this paper introduces a new web-based system which called optimal management system of water distribution networks with the goal of calibration of water distribution network based on simple modified particle swarm optimization (SMPSO) in a simple and user friendly way for the experts of the water and wastewater companies. The calibration process in this web-based system is aimed to minimize Mean Absolute Percentage Error criterion (MAPE) between simulated and observed pressures with the Hazen- Williams roughness coefficients as the decision variables. To achieve this purpose, firstly the SMPSO method is investigated to calibrate a benchmark network which the results showed MAPE average has reduced to 0.425, 2.857 and 0.306 percent in the maximum, minimum and fire demand conditions respectively and has increased 0.186 percent just in the normal condition. It is verify that the SMPSO algorithm performs better than the GA. Then the system is used to calculate a real case water network in the normal, maximum, minimum and different demand conditions during the 24 hours which in these condition MAPE values have decreased 5.82,6.20,5.21 and 5.95 respectively, when compared with calibration obtained by consulting company.

Since water distribution networks have very high execution costs, it is essential to discuss the optimal design of these types of networks. In this research, Central Force Optimization (CFO) was used to optimize Ismail Abad irrigation water distribution network. This network that is pressurized network and includes 19 pipes and nodes 18. Optimization of the network has been evaluated by developing an optimization model based on CFO algorithm in MATLAB and the dynamic connection with EPANET software for network hydraulic calculation. Central force algorithm for conditions of probes 42, 15% mutation rate, the number of iteration equal to 1,000 (Nt = 1000) and initial acceleration probe is zero showed the best performance. The optimal solution for Ismael Abad irrigation water distribution network show that CFO (737,924 $) is %1.55 more than the absolute optimum (Shahinezhad, 1390) that determined by the MILP method.

In this study, soil water and salinity distribution in surface drip irrigation (DI) and subsurface drip irrigation (SDI) systems with saline water were investigated. Plant measurements were used to obtain water stress response function parameters that are needed for HYDRUS-2D modeling. The hm50 and EC50 parameters that are the 50% reduction of water extraction due to pressure head and salinity, were calculated 8925 cm and 29.7 dS/m, respectively. HYDRUS successfully simulates soil water and salinity distribution in pistachio trees root zone. The results showed that in the immediate vicinity of the emitter, the soil salinity varies in a relatively low range and salt accumulation was observed far from the emitters. Also HYDRUS calculates daily transpiration and root water uptake that they were significantly correlated with stomatal conductance and sap flow. Plant measurements and HYDRUS results show that roots water uptake in SDI significantly was more than DI. Therefore, using SDI, by decreasing surface evaporation and conducting appropriate water and salt distribution in root zone reduce water and salinity stress. Furthermore, results revealed that soil moisture reduction after five days from irrigation, lead to limitation in root water uptake. so, it is necessary to decrease irrigation period from that applied in the field.

Climate change and global warming are one of the most important issues in the world in the current era and are spreading all over the globe and its harmful effects on water resources are not overlooked; Therefore, forecasting the climate change of an area will play an important role in the planning and management of water resources. The purpose of this study is to evaluate the effects of this phenomenon on the discharge of Tajan watershed in the upcoming period. For this purpose, in the first step, the simulation of temperature and precipitation parameters was performed using the CANESM2 atmospheric model under the new RCP2.6 and RCP8.5 release scenarios and microscopic atmospheric model outputs with SDSM model. Then simulation of daily discharge of the basin was carried out in the future period with the IHACRES rainfall–runoff model. Non-parametric Mann-Whitney test was used to check the performance and error of SDSM downscaling model, which illustrates the model's performance in the downscaling of temperature and precipitation at the studied stations. In general, the results of the model showed that the average annual temperature of the basin in the upcoming period (2020-2049) compared to the base period of this research (1976-2005) will increase under two scenarios RCP 2.6 and RCP 8.5, 1.14 and 1.57 and amount of precipitation will decrease under the same two scenarios, 59.72 and 70.98 mm, respectively. In the final step, the results of IHACRES calibration and validation were examined. In the final step, the results of the IHACRES calibration and validation were checked. During these two stages, the Nash-Sutcliff efficiency coefficient (0.45 and 0.40) was obtained, which indicates the acceptable accuracy of the model in the simulation of the discharge. According to the results of this research, it was predicted that discharge under two scenarios RCP 2.6 and RCP 8.5 will decrease 19.8 and 21.7% respectively in the upcoming period compared to the base period.

Water resources limitation and population growth that requires increased food production, indicates the necessity of promoting water productivity in irrigation networks. Productivity improvement methods in irrigation networks consists of supply and demand oriented methods. In this research considering limitation of supply oriented practices, the emphasis is on demand oriented methods especially under water shortage condition. For this purpose, water distribution management in irrigation networks (including 4 scenarios) are considered. This research has been done on a secondary eastern canal of Gotvand irrigation network in Khuzestan province. Hydraulic flow in this network is simulated with the ICSS hydrodynamic model. The crop production has been simulated with the AquaCrop model. Depending on the management goal i.e. saving water, food production and improving water productivity, the scenarios can have different priorities. If the main goal is to improve water productivity, the first and fourth scenarios are the most suitable strategy with 13.8% and 12.96% improvement in productivity compared to the current situation.

This paper investigates the effectiveness of Kriging and Inverse Desistance Weighting (IDW) methods and Hotspot analysis in evaluation of groundwater quality in Kerman Plain, Iran. In order to conduct this study the information regarding the concentration level of electrical conductivity (EC), total dissolved salts (TDS) and sodium adsorption ratio (SAR) of 60 exploiting wells in the study area were obtained. The positional accuracy and correctness of this information were confirmed. Then, interpolation maps were produced for EC, TDS and SAR parameters using the raw data and the output of hotspot analysis (Z-Score) with the application of IDW and Kriging methods. This result demonstrates preferability of Kriging in regard to IDW using the output of Hotspot analysis (Z-Score), as the experts don’t interfere with the range and number and produced maps are based on geostatistical analysis. Furthermore, the resulted maps indicated sharp boundaries of very high and very low concentration of each parameter and the calculated area for EC (1411, 1063 km2), TDS (1874, 1470 km2) and SAR (321, 396 km2) are very close to reality. Accordingly, applying the output of hotspot analysis in combination with other interpolation methods can assist researchers in determining the extent of very high and very low concentration of a parameter and in calculating the area of the affected region.

The objective of this study was the evaluation of the Ceres-Rice and ORYZA2000 models under different water-managements and planting densities of Rice, in order to determine difference between potential and actual yield and invest its reasons. An experiment was conducted in a randomized complete block design (RCBD) with three replications in Kooshal-Lahijan located in north of Iran during cropping seasons of 2014 and 2015. There were irrigation treatments in this research including: I1 = Full irrigation, I2 = Saturation, I3 = Irrigation with 8 days alternative before anthesis, I4 = Irrigation with 8 days alternative after anthesis, I5= Irrigation with 8 days alternative whole growth season) and there were density including, D1=15×15, D2=20×20, D3=25×25cm. Evaluation simulated and measured yield and biomass by adjusted coefficient of correlation and by absolute and normalized root mean square errors (RMSE). ORYZA2000 model was more accurate in simulation of grain yield (RMSE= 533 and RMSEn= 14%). Observed and predicted of I3D2 showed good agreement in both calibration and evaluation steps. The average amount of water-based components of irrigation, evapotranspiration, transpiration and total evapotranspiration and deep penetration (WPI, WPI + R, WPET, WPT and WPETQ) simulated by the ORYZA2000 and Ceres-Rice models, were 1.09, 0.90, 1.00, 1.59 and 0.79 kg/m3 respectively.

The phenomenon of evapotranspiration causes water and moisture losses from water, soil and vegetation levels. Due to the small amount of atmospheric precipitation and water resource constraints in Iran, it is important to calculate it through a suitable method. The present research attempts to evaluate the Reference crop evapotranspiration (ETo) and investigate its relationship with land use. Also long-term land use changes was considered its effects on evapotranspiration changes in the Saqqez catchment. In this study, the long-term mean values of temperature, humidity, sunshine and wind speed data at seven meteorological stations and evaporation pan data of Saqez station were used to determine the appropriate ETo estimation method. TM, ETM and Landsat 8 satellite data and ENVI and GIS techniques were used to extract land use classes during the years 1992-2013. The results of the research indicate that the best method for this region as the cold and moderate climate was FAO radiation and Blaney-Criddle with R2 = 0.89 and Nash –Sutcliffe = 0.86 and R2 = 0.94 and Nash –Sutcliffe = 0.92 in Bijar and Sanandaj station respectively. The results of land use changes indicate that the main changes in land use related to the reduction of area in the rangelands and the increase of area in urban areas, water coverage, agricultural land and garden lands. Also, the results of correlation between evapotranspiration and land use indicate that the highest correlation (0.96) was obtained on agricultural lands and the least correlation (0.38) was observed in the surface area of the rivers.

In the midst of extreme events, the drought is occurring gradually and taking its effects during the longer time. Among the drought monitoring methods, Nalbanti proposed SDI method based on the analysis of drought characteristics based upon the volume of the cumulative river. Being easy is of this method’s advantages. This method has been used to analyze the drought characteristics of many countries such as the United States, India, Iran, Iraq, and Greece. The mean of average annual precipitation is 437 mm in Kermanshah province which has been increased in recent years during the humid season and has been decreased during the dry season, for climate changes and temperature increase. The difference in river volume between the humid and dry seasons has led to the drought. This research aims to investigate the continuity and severity of hydrological drought via using Streamflow Drought Index (SDI) based on the 3, 6, 12, 18 and 24-month periods in this province. Daily Dubai data was used from 10 hydrometric stations for a 31-year period (1981-2011) in order to achieve this goal. The result of the river flow index showed that wet years began in 1363 and continued until 1998 at the stations of Totshami, Shah Gozar, Arangharb, Doab, Polchehr, Khers Abad, DuabMerk, and Ghorbaghestan. And the drought began since 1998 at the stations of Totashi, Arangharb, Plochehr, Khers Abad, DuabMerk and Ghorbaghistan and continued till the recent years (2011).

The Rainfall and runoff models are one of the methods for estimating runoff and are suitable tools for studying hydrological processes and assessing water resources. This study amid toevaluate the accuracy of precipitation and run-off estimation from the TRMM Satellite and it’s modified in Shapour river basin in Fars province. For this purpose, the hourly, daily and monthly rainfall data of stations which located in the Shapour basin during 2011-2016 were used. In continue, the calibrated HEC-HMS model was used to assess using precipitation gauge data and satellite TRMM imagery as input in this model to estimate run-off. According to the results of the modified TRMM and corrected TRMM models have less accurate precision in the hourly and daily scales as compared to monthly scale. The results of rainfall estimation from the modified TRMM model in the monthly time scales have the explanation coefficient (R2) more than 0.86 at the studied stations. The results of rainfall-runoff simulation of the calibrated model also showed that the best result of the estimated runoff from the station's rainfall data was obtained, with an RMSE equal to 11.94 m3/s.

Studying climatic processes provides plan makers with a suitable tool in different sectors to plan future policies for optimizing cost and maximizing productivity while bearing these studies in mind. Precipitation is associated with complex atmospheric processes including the El Niño–Southern Oscillation (ENSO) that is inextricably linked to the oscillations in the surface water temperature of the Pacific Ocean. The objective of this study was to investigate the relationship between rainfall in wet seasons of the year (cold season for six months) and the El Niño Southern Oscillation (ENSO) in the Persian Gulf and Oman Sea. After conducting adequate investigations, 12 synoptic stations with appropriate statistical period were selected and the homogeneity and adequacy tests of the data collected were carried out on rainfall amounts. The Southern Oscillation Index (SOI) was used to investigate the effect of the El Niño Southern Oscillation. The warm and cold phase was determined using the SOI index. Also, the longest droughts and wet years were identified and the wet and dry years associated with the warm phase (El Niño) and the cold phase (La Niña) was specified as well. The results showed that the wet years occurred in warm phase and droughts occurred during the cold phase so that at the same time as the dry years, rainfall in the stations under investigation was lower than normal, and the numerical value of the SOI index was lower than normal. The numerical value of the SOI index obtained in dry years was negative. While, at the same time as wet years, the amount of rainfall at the stations is more than the average annual precipitation of the investigation period and the numerical value of the SOI index is also positive and indicates higher values than normal.Pearson correlation test was used to investigate the correlation between rainfall and SOI index. The correlation was carried out on a monthly, seasonal, annual, and moving window basis. The results showed that on the monthly basis, the highest correlation was registered at Konarak station, on the seasonal basis, at Bandar Abbas, Bandar-e-Lengeh, Jask, Kish, Konarak, Bushehr and coastal Bushehr stations, and on the annual basis, at Abadan and coastal Bushehr stations at a significant level of 99%. It is also possible to conclude from the correlation of the moving window that the signal has the most effect on Bushehr, coastal Bushehr, Bandar Abbas, Kish, and Konarak stations in autumn and winter.

Groundwater resources are important production factors in agricultural production. The excessive extraction of groundwater resources and the unfair weather conditions have made the important challenges in water resources management. According to this, reconsideration in management of water resources seems necessary. Shabestar plain is one of the most important areas of agriculture in East-Azerbaijan province that confront with excessive extraction of groundwater and water resources crisis. Given that rainfall is the main factor in nutrition of groundwater resources so, in this study was tried to investigate the effect of rainfall indices on volume and consumption of groundwater and cropping patterns using the dynamic programming model in Shabestar plain in ten-year (from 2001 to 2016) horizon. The results showed that there is strong correlation between 48-Monthly Standardized Precipitation Index (SPI48) and Groundwater Resource Index (GRI) and height of aquifer. Seting water pumping height on SPI48 caused the balance of aquifer gets better. In the current state of extraction, the aquifer's negative balance is about 10.44 million cubic meters per year. With the optimal extraction, the aquifer's negative balance of 8.26 million cubic meters in normal conditions decreases. If optimal water extraction is done according to the weather conditions, In the drought and normal conditions, the negative balance would be about 9 and 6 million cubic meters, respectively. In wet year conditions, the aquifer's balance will be positive and about 10 million cubic meters will be added to the aquifer volume. According to the results, in drought conditions crops cultivation of wheat, barley and grape increased and crops cultivation of tomato and alfalfa decreased. Reduce water extraction and consumption by using water saving irrigation technologies and also applying appropriate prices for low-water crops are the basic strategies for restoration of groundwater table in the Shabestar region.