مجله مهندسی آبیاری و آب ایران
پیاپی 47 (بهار 1401)

In this paper, the effects of bed vegetation density, inflow rate and slope on some hydraulic properties of flow was studied in a laboratory environment. For this purpose, a trapezoidal flume with 3m long was established and some hydraulic characteristics of flow such as water level, manning roughness coefficient, longitudinal velocity, deep velocity and bed shear stress were recorded in different flexible artificial bed cover densities (VD= 0,20%,30%,50%) inflow rate (Q= 5,10,15,20,25 lit/se) and slope (S=0, 0.5%,1%). Final results analysis showed that behavior of hydraulic parameters depends on the interaction between inflow rate and slope and vegetation density. Water level and manning roughness coefficient increased nonlinearly with increasing bed vegetation density at a constant inflow rate. Maximum water level and roughness coefficient were observed in S=0, VD=50%, Q=25, 5 lit/se respectively. Also, with increasing bed vegetation density at a constant inflow rate, deep velocity and shear stress decreased nonlinearly and longitudinal velocity decreased linearly. Minimum longitudinal velocity and shear stress were observed in S=0, VD=50%, Q=5, 25 lit/se respectively. Froude number decreased with increasing vegetation density at a constant inflow rate. Maximum Froude number was seen in VD=0, Q=25 lit/se.

Culvert is one of the main structures in drainage systems at crossing with railways and roads. Flood flows, along with the transport of sediments and floating debris, can cause blockages and backwater, thereby reducing flood flow capacity. The main purpose of this study was to physically model and numerically simulate the effects of different percentages of blockages on culvert hydraulic characteristics. Blockage effects investigated in 21 laboratory experiments. Complementary tests were carried out with the use of OpenFOAM numerical tool box. Three blockage scenarios have been numerically simulated with 20, 40 and 60 percent coverage of inlet area. The numerical model was calibrated using the experimental data. The simulation results of OpenFOAM in different culvert inlet blockages indicated that the LES turbulent model is more adaptive than RAS models. The main flow characteristics were compared with the corresponding simulation results from the trademark FLOW-3D model, and showed good agreement for verification purpose. Results for different flows (i.e. 40, 60 and 100 percent of the design discharge) showed that the increasing rate of upstream water level is not identical, and is higher for the lower discharges. Blockage also intensifies turbulence and shear stress levels in the outlet section. For design discharge, the 40 percent blockage resulted in the increase of shear stresses up to 10 times, which cause severe scour in downstream channel.

Scouring is a natural phenomenon that occurs as a result of the erosive factor of water flow. Due to the impact of water on the base of the pier, vortices called horseshoe vortices are formed. Horseshoe vortices are more active in front of the base, which is the main cause of scouring. In this study, the effect of using triangular structures on reducing scour around the pier bases was investigated in a laboratory. This research was used in a laboratory flume with a 90-degree arc. Triangular protective structures with angles of the 15, 30, 45 and 60 degrees and a curved triangular structure were considered. Experiments were performed at the 6, 7.5, 8.5 and 10 liters per second. The results showed that the installation of triangular protective structures at a maximum flow rate of the 10 liters per second, can reduce the scour depth flow up to 84 and 78 percent, respectively, upstream and downstream. The best performance is for the 15° upstream protection structure as well as the 60° downstream protection structure. The results show that the scour depth increases with increasing landing number. Also, the curved protective structure had a benign performance current upstream and a lower performance current downstream than other protective structures.

Embayment or Side-cavities are built as a natural or artificial complication, which generally has shallow flow conditions, as affecting the hydraulic conditions of the flow. These complications affect important hydrodynamic processes that play an important role in the general behavior of the flow by creating secondary structures and shear layers. Therefore, the experiments were performed in an Embayment with a size of 0.3 * 0.3 m, adjacent to a canal 0.5 m wide. Speed measurements in the defined network were performed using the Vectrino 3D Velocimeter. Observational results confirmed the existence of a large-scale gyre in the interior of the embayment. Further analysis of the data showed that the velocity in different directions is affected by flow of the main canal and with increasing current in the main canal flow, the velocity in the embayment also increases. Also, the results showed that at a constant flow through the main channel, with increasing flow depth, the speed in the outer half of the embayment decreases as the main channel but in the inner half, the speed increases with increasing depth. This indicates as increasing depth, a greater advancing of the stream into the embayment would be observed.

In recent decades, several models have been developed to simulate farm water management. The main focus of most researchers is obtaining more products per unit of water consumed. Water productivity defined as crop yield per unit of water consumption. Due to limitation of water resources and its optimal consumption in order to save water and increase its productivity, this study was conducted to simulate water productivity indices of rice (Hashemi caltiver) using SWAP model in paddy soils at field scale. For this purpose, two closed-ended lysimeters were used to measure the actual evapotranspiration. The quantity of evapotranspiration was measured daily and water productivity based on irrigation water (WPir) and evapotranspiration (WPET) was calculated and compared with the simulated values afterward. The obtained results indicated that the SWAP model had a high accuracy for estimating amount of yield (R2=0.90 and RMSE=648.73) and the amount of water consumed in the evapotranspiration process (R2=0.89 and RMSE=164.07). Using the calibrated SWAP model, the water productivity indices from division of yield on evapotranspiration (WPET) and yield on irrigation water (WPir) in the studied farm was estimated amount of 0.553 and 0.876 kg/m3, respectively. Also, results showed that with increasing irrigation efficiency, elimination of deep percolation and reduction of evaporation, water use efficiency increases by 30%. In general, for optimal management of paddy soils in field scale and considering the optimal yield at harvest time, serious attention must be paid to water efficiency to come up with most effective ways to deal with water crisis and to increase the quantity and quality of rice production.

Analysis of the unsteady flow on the weir end sill is fundamental to determining the passing flow's exact flow discharge and height. Due to the difference between the steady and unsteady flows and the effect of different terms of the Saint-Venant equation, the weirs' stage-discharge curves under the two types of flows are different. In the present study, 3D free-surface flow on the Ogee and the Piano-key weirs under steady and unsteady flows was modeled using the FLOW-3D numerical model, and the effect of different input hydrographs for multiple time bases was investigated. Based on the obtained results, the steady flow condition's unit stage-discharge curve turned into a circular curve in the case of the unsteady flow condition. In both types of the weirs, by increasing the hydrograph time base, the stage-discharge curve changed from a circular curve into a unit curve and finally conformed to the steady-state's stage-discharge curve. In both types of studied weirs, for a constant flow discharge, the water head difference was more considerable for the hydrograph with smaller base-time, i.e. the hydrograph with steeper ascending and descending branches. The amount of head difference in the ogee weir due to your hydrographs with time steps of 4, 10, and 40 seconds is 0.023, 0.013, and 0.008, respectively, and for the piano key weir is 0.024, 0.019, and 0.009. In other words, for steeper input hydrographs on the end-sill of the weirs located on the channels or the weirs used as a diversion, an unsteady flow analysis should be performed. For a fixed weir height and a fixed input hydrograph, water head changes of the Piano key weir were greater than the Ogee weir.

Irrigation water and nitrogen fertilizer management have an effective effect on tomato yield and water use efficiency. So, it is important to know the best amount of irrigation and nitrogen fertilizer for tomato cultivation. Since doing farm researches need time and funds, it is necessary to use crop growth models like AquaCrop. Regarding that, data collected from Ismaeel Abad research station was used. The study was conducted there, irrigation was considered as four levels (E1: 50, E2: 75, E3: 100, and E4: 125 mm evaporation from pan class A) and fertility uses was considered as three levels (F1: 70, F2:100, and F3: 40 percent as fertility needed). At first, AquaCrop was calibrated without considering any fertility stresses using first year data. Then, F3 treatment in the first and second year was used to calibrate AquaCrop for fertility stress (40 percent as fertility needed). Results showed high correlation between observation and simulation values for yield (R2=0.915) and water use efficiency (R2=0.893). MBE, RMSE and NRMSE values showed a good precision for the model. The mentioned values were -0.02 (ton.ha-1), 0.42 (ton.ha-1) and 0.07 for yield, respectively, and -0.01 (ton.ha-1), 0.02 (ton.ha-1) and 0.03 for water use efficiency, respectively. Due to AquaCrop efficiency for simulating tomato yield (EF=0.41) and water use efficiency (EF=0.19), it is recommended to use AquaCop for simulating tomato yield and water use efficiency.

Limited resources, including water, especially in our country is one of the challenges facing the agricultural sector. Due to the limitations of this vital resource, Iran's agricultural sector can control this crisis to some extent by properly managing the use of water resources, including increasing water use efficiency. In this research, water consumption efficiency and its effective factors in grape production in Bijar County have been estimated using data envelopment analysis method with input-oriented approach. The data of this study were obtained by collecting a questionnaire from 170 gardeners in this city during the 95-96 crop year. Also, the average results of estimating water use efficiency in CRS and VRS conditions were 51.94 and 83.59%, respectively. This difference is due to the inefficiency of the scale in grape production in this county. Therefore, with the increase of production scale in this region, the amount of water consumption efficiency will also increase significantly. The results of the study of factors affecting water use efficiency showed that the variables of education and history of grape production are significant and as education and history of grape production increase, water use inefficiency decreases. According to the research results, by educating and consulting with the help of sample producers, it is possible to increase water use efficiency in grapes production in Bijar County.

Regarding the scarcity of water resources in arid regions of the world, using more efficient irrigation systems is essential in agriculture. Possible option for improving agricultural water productivity is the irrigation method using steam- pottery system. This study introduces a new method of pottery irrigation system that is capable of transferring moisture and nutrients into the soil. The experimental system consisted of two clear plexiglasses with the dimension of 130 × 40 × 40 cm. The clay pipes were used in each of the boxes had the same dimensions (length 90 and diameter 5 cm). Perlite-coco peat is used as a soil. The volumetric moisture content of the soil was measured by using an analog moisture meter. The data recorded by the sensors were analyzed in both the steam-pottery system, and the water-pottery system. The results show that the distribution of moisture is uniform for both of them, in terms of time and space. However, the amount of moisture in the steam-pottery system is less than water-pottery system. The result is that in the steam-pottery system, the water demands of the plant are met, with total water use less than it was in the water-pottery system.  Other advantages of the steam-pottery system over the water-pottery system are that the pipes are not clogged and their service life is greatly extended

Arching in core dam can reduce tension and create scour and clay scrub damage, so it is always a major issue in the earth's dams. In this research, Geostudio software, which is a powerful software for limited components, is used to study the total stress and aridity coefficient of Marvak earth dam. In modeling the dam, a Mohr-Coulomb behavioral model has been used and the effect of the construction has been considered. By analyzing the stress-strain during the construction of the dam and the effect of the construction, the results of total stress and arching coefficient were evaluated and compared with the results of the instrumentation. Multivariate regression and coefficient of determination were used to fit the observed and predicted data and the value of R2= 0.9834 was obtained, which is a very good agreement between the observed and predicted arching data. The results indicate that as the embankment increases, the total stresses also increase, and the highest arching percentage from the beginning to the end of the construction phase is 58 percent and at the third of the core of the foundation. Due to the great effect of consolidation on the arching severity, the speed of construction should be chosen in such a way as to be part of the consolidation of the underlying layers before the upper layers are applied. It is also possible to reduce arching by choosing the appropriate filter between the core and the shell and using materials with a Poisson's ratio.

The catchment area of ​​the Minab river basin and its main branches, as a part of Makren coast, southern Iran, are one of the important areas for water resources planning and management. The aim of this study was to set-up a comprehensive water resource planning and management model, involving WEAP software, for the area. The area includes the Minab, Jeghine Toukahoor, Manoojan, Roodan, Nodej, Dehkohan, Mosaferabad and Faryab Galashgerd. Two scenarios including: (RS) as the reference scenario, and a conservative agricultural development (CAS) were implemented for the future horizon of year 1410, using WEAP model. Then the outputs were evaluated using the performance criteria including; volumetric reliability, reversibility, vulnerability and stability indices. A 15-water year data (2000-2014) was used, 10 years of that for calibration purposes and the rest of 5 years data for verification. The values of evaluation indices, coefficient of determination and Nash-Sutcliff coefficient, for calibration period were equal to 0.98, 0.97 for the Esteghlal dam volume and 0.98 and 0.98 for the hydrometric stations, and 0.90 and 0.86 for the groundwater aquifers, respectively. On the other hand, for the verification period, the values of the above-mentioned indices were equal to 0.98 and 0.98 for Esteghlal dam volume, 0.78 and 0.70 for hydrometric stations, and 0.97 and 0.88 for the groundwater aquifers, respectively. The above-mentioned index values indicate that the modelling results are acceptable. Moreover, between the two considered scenarios, the scenario of conservative agricultural development, with a sustainability index of 55.47%, has a higher priority.

The study of behavior of water level fluctuations is important for water balance due to the unbalanced distribution in the hydrological cycle. In present study, the groundwater level fluctuations of Urmia and Miandoab plains in two models SVM and Wavelet from the group of soft calculations have been investigated. For this purpose, information about the period years of 1381-1386 for both plains of Urmia and Miandoab by considering four scenarios of groundwater level -groundwater level with a delay of one month, groundwater level -groundwater level with a delay of two months, Groundwater level -precipitation and groundwater level -temperature. The simulation results were compared and the best model was introduced. The results of regression analysis showed that R2=0.9 and MSE=0.4 belong to the second piezometer well of Urmia plain and the third piezometer well of Miandoab plain in both SVM and Wavelet models for 3 scenarios of groundwater level -groundwater level with a delay of one month, Groundwater level was precipitation and groundwater level was temperature. Data on climatic variables of temperature, precipitation and groundwater level with a delay of one month as an independent variable and groundwater level data as a dependent variable formed the mentioned scenarios with 80% of educational data and 20% of test data. The results showed that the climatic variable of precipitation has a significant effect on groundwater level fluctuations. In general, the prediction results of Wavelet model were better than SVM model in investigating groundwater level fluctuations in Urmia and Miandoab plains. In the present study, an independent study of the mentioned models in order to simulate groundwater level fluctuations and compare each of the two models in their application.

Due to the complexity of the nature of groundwater systems as well as the limitations of borehole drilling, temporal and spatial modeling of groundwater levels are not readily possible. Artificial intelligence methods such as RBF, ANN, SVR, ANFIS and ARIMA modeling and their combination with geostatistical methods have been used to find useful solutions for spatial prediction of groundwater level. The case study of this study is Semnan plain. The first step is the temporal modeling of groundwater level using different methods. The results showed that the ANFIS model provides more accurate prediction of the monthly groundwater level in the experimental stage than other methods (R2 = 0.994 and RMSE = 0.041). Next step, the ANFIS output data is used as input data for the geostatistical model and the linear kriging model is selected as the best model for spatial development of groundwater level. (R2 = 0.8889 and RMSE = 2.376). The results of this study showed that the combination of ANFIS model and linear kriging model is an appropriate method for temporal and spatial prediction of groundwater level.

The main purpose of this study is to evaluate the effect of type of water resource in simulating water quality parameters in Savel plain by the intelligent models. In this investigation, the performance of ANN and CANFIS models in simulation of TDS, SAR, EC, and TH were compared with each other. For this aim, considering the correlation of the parameters, the Ph, Ca, Mg, Cl, and SO4 from 1966 to 2016 were selected as the input variables. The results indicated that the minimum error by the ANN in groundwater and surface water resources were related to the TH and the EC with 1.29 and 5.3 % respectively. The maximum error in both resources corresponded to the SAR. The same results were obtained by the CANFIS. The consequences of the T-Test showed that there was a significant difference between the ANN and the CANFIS in estimation of the SAR in the groundwater. So that the value of NRMSE decreased from 32.9% in the ANN to 22.82% in the CANFIS.  Concerning the other parameters, there was not any significant distinction. In case of the surface water, the CANFIS led to increase of proficiency of simulation of the SAR and the TDS. So thar, the value of the NRMSE declined from 60.35 and 29.27% in the ANN to 28.72 and 16.85 % in the CANFIS. In general, the impact of the type of the water resource in the accuracy of intelligent models in simulation of water quality parameters was approved.

In this study, to predict the effect of climate change on hydro-climate variables in the study area, based on downscaled outputs from atmosphere general circulation models, the most appropriate scenarios were used. For this purpose at first, by valid trend tests, climate change in the case study was valued during the base period (1976-2005). Then the CanESM2 model under RCP2.6, RCP4.5, and RCP8.5 scenarios in three future periods (2039-2010) (2040-2069) and (2070-2099) was used, and the SDSM model was used to downscale the climatic data. The results of the simulation for future periods and comparison the results with the base period indicated that average temperature increase between 1.3 to 5.7 (ºC), the mean annual precipitation under the RCP4.5 scenario for all three future periods decrease and for RCP8.5 scenario for all three periods increase and also for RCP2.6 it has a reduction of precipitation for 2010-2039 and precipitation increase for other two future periods. The IHACRES model was used to simulate runoff. The results showed that for all periods and RCPs scenarios, the runoff decreases between 10 to 38% in comparison with the basic period. Based on the results of this study, increasing temperature and decreasing precipitation over the next years will reduce the runoff and water resources of the region due to increased evaporation and transpiration, which in the future will increase the probability of increasing drought and flood in the region. Therefore, to adapt to climate change, appropriate managerial approaches at the watershed should be considered.

The effect of precipitation changes on water resources, agricultural production reveals the need for accurate methods for precipitation forecasting. In this research, one of the soft computing methods was developed in order to forecast precipitation with the data reduction approach. Input data of model was mean air temperature, dew point temperature, mean sea level pressure, mean station pressure, mean relative humidity and mean wind speed at Tabriz, Ahar and Jolfa stations. The method used in this study includes Epsilon and Nu support vector regression. In all studied stations, the use of Nu support vector regression compared to Epsilon reduced the error so that UII values ​​with Nu support vector regression in Tabriz, Ahar and Jolfa stations were decreased 19.19, 5.88 and 15.78%, respectively. The results indicate the limitation of using the data reduction approach for data with KMO factor lower than 0.5, which included Tabriz and Ahar stations. Principal component analysis in both types of support vector regression increased the performance of the model so that in Jolfa station by using principal component analysis d values ​​of Epsilon and Nu support vector regression increased by 16.6 and 17.5%. Execution of Verimax rotation in preprocessing of input data to regression was stronger than principal component analysis. In this regard, RRMSE and RMSE values ​​in Jolfa station using Epsilon support vector regression were decreased 6.66 and 6.45%. Therefore, principal component analysis is a suitable tool to improve the performance of soft computing methods by regarding the relevant constraints.

Water is the most valuable asset to human beings, especially in Iran, where large areas are covered by arid and desert regions, while Iran has the highest freshwater extraction (90-94 percent) for agricultural use. . Virtual water integrates agricultural and economic concepts with emphasis on water as a key factor in production. On the other hand, one of the most important economic policies of governments on agricultural products is a guaranteed purchase policy to protect the producer. Therefore, the purpose of the present study is to investigate the effects of guaranteed purchase policy on virtual water in Yazd province for the period 1368-1977. The results of estimating self-verification and error correction models showed that the variable of virtual water index, production amount, average cost and virtual variable had a significant positive effect on the guaranteed price of wheat. and between the guaranteed price, vitual water and the average cost there is a causality and positive long-term relationship Also, the change in price from the guaranteed price variable has a negative and decreasing effect on the virtual water over a period of ten years, but at the end of the shock and long-term it is moderately positive in the positive region with little downward effect. Consequently, it should be considered as an important factor in the adoption of supportive policies, especially the guaranteed purchase policy, as well as to support the manufacturer of the guaranteed purchase policy with respect to the virtual water variable.

In order to investigate the effect of magnetic intensity and salinity on germination characteristics of Cuminum ciminum, an experiment was conducted in medicinal plants laboratory of University of Torbat Heydariyeh. Four levels of magnetic field intensity (0, 40, 80, and 120 milli Tesla) as the first factor and four levels of salinity stress (0, -3, -6, and -9 bar) as the second factor was applied. The results showed that salinity was significant on all studied factors including germination percentage, germination rate and mean germination time, seedling weight and length and seed vigor indices I and II at 1% level. Increasing the salinity level reduced the seed germination percentage from 97% in the control treatment to 25% in the -6 bar salinity treatment. Magnetic field also had a significant effect on shoot, root, and seedling length and seed vigor index I factors at the level 1%. In addition it had significant effect on the germination rate and mean germination time at the level of 5%. Application of magnetic field with an intensity of 120 mT increased the weight of shoot, root and seedling by 44.2%, 59.2%, and 52.5% compared to the control, respectively. The interaction of salinity and magnetic field showed a significant effect on shoot, root, and seedling length and seed vigor index I at the level 1%. The general conclusion of this study showed that with increasing salinity, germination percentage decreased and with increasing magnetic field, seedling weight increased. Increasing the length of shoot, root, and seedling also was one of the positive effects of increasing the intensity of the magnetic field

Identifying land potentials based on environmental resources in each region such as climate, soil and topography is the first step in developing a sustainable agricultural system. To this end, in this study, the land suitability of Jiroft city for rainfed and irrigated Rapeseed cultivation was studied using Fuzzy-AHP model in GIS. Therefore, the weight and importance of information layers such as climate (temperature, precipitation and Growth Degree Days), topography (slope & altitude), soil (EC, pH and soil type) along with access to water resources were separately obtained for irrigated and rainfed Rapeseed cultivation based on analytical hierarchy process (AHP) method. Then the information layers were classified and fuzzified according to the environmental requirements of the Rapeseed crop in the GIS environment. Finally, the overlap of the layers was done by multiplying the weight obtained using the AHP method by the fuzzy layers. Finally, the land suitability map was separately prepared and classified for irrigated and rainfed Rapeseed cultivation. The results of land suitability assessment for irrigated Rapeseed cultivation showed that 14.7, 24.75, 21.61, 26.02 and 12.91% of the total area of the study area have located in very suitable, suitable, moderate suitability, low suitability and unsuitable classes, respectively. Also, the results of land suitability assessment for rainfed Rapeseed cultivation showed that 12.65, 18.46, 24.4, 22.82 and 21.76% of the total area of the study area have located in very suitable, suitable, moderate suitability, low suitability and unsuitable classes, respectively. In this classification, the factors of access to water resources for irrigated cultivation and rainfall for rainfed cultivation were the main factors limiting canola growth. These results can be useful for policy makers and farmers to design a suitable cultivation pattern.

Since the sustainable agriculture field is the main water consumer, using techniques in order to increasing water use efficiency is necessary. An investigation was done to evaluate effects of different regimes of urban wastewater on chemicals properties of soil, yield and water productivity of Quinoa plant (cv. Titicaca), at Research Greenhouse of Ferdowsi University of Mashhad, during 2017-2018. The research was based on completely randomized design with three replications in greenhouse conditions and in pots. Five applied treatments were urban fresh water, urban wastewater, alternate wastewater and fresh water, mixture of 50-50 percent wastewater and freshwater, and subterranean irrigation with urban wastewater. The results show that the treatments were significant on K, P, N, and water productivity; grain yield was significant at 1 percent level (P<0.01), but on pH and 1000 kernel weights at 5 percent level (P<0.05). The research shows effects of using urban refined wastewater on an increase in all traits. The treatments of urban wastewater, alternate, mixture of 50-50 and subterranean irrigation resulted in an increase of 30.7%, 8.8%, 20.6% and 36.1% of grain yield, 31.1%, 8.6%, 20.5% and 36.4% of water productivity, 8.8%, 6.7%, 7.5% and 9.6% of 1000 kernel weights, respectively. Furthermore, the results of the experiment show that the use of refined sewage water for irrigation of Quinoa crop can increase the yield of Quinoa, positive effects on the chemical properties of the soils of the studied, and decrease the cost of supplying and using fertilizers, and then save the environment.

Agricultural development depends on the optimal use of resources and the optimal use of resources depends on the optimal allocation of agricultural land to different crops. Every farmer cultivates different crops during a growing season, but there is no certainty that this cropping pattern used by the farmer is the optimal cropping pattern. Considering the importance and role of optimal cultivation pattern in the sustainable production of agricultural products, the purpose of this study is to present the optimal cultivation pattern of crops in Gorgan under three scenarios: optimization of economic efficiency, production maximization and simultaneous maximization of economic efficiency and production with emphasis on Water consumption management. In this regard, in order to achieve the optimal cultivation pattern with the desired goals, the genetic algorithm was used and to obtain the need for irrigation, CROPWAT software was used. The studied crops include wheat, barley, and rice, soybeans, sunflower, beans, and cotton and fodder corn. The results showed that the current cultivation pattern of the region was not optimal. Based on the results of optimization with a genetic algorithm, forage corn crop has been removed from the crop pattern and the area under rice cultivation has decreased compared to the current crop pattern in the region, in all optimization scenarios. The area under sunflower and soybean crops increased in all three scenarios and replaced rice and fodder corn crops. Wheat and soybean crops have the highest area under cultivation in optimization scenarios and the lowest area under cultivation in all three scenarios is related to cotton. In the current situation, the total water consumption is 213.626 × 106 m3, which decreases to 234.277 × 106 m3 after optimization.

In order to estimate the amount of soil moisture by the Crop Water Stress Index (CWSI), research was performed on the maize (SC 704). The experiment was a factorial and in format of randomized complete block design. In the control, treatment was done full irrigation and in other treatments, was applied water stress in the stages of 6-leaf, 12-leaf, flowering and seeds milking. The meteorological parameters, stomata resistance and leaf surface temperature were measured daily. At different growth stages, the stress low line had a slope of 0.09 to 0.14. The amount of the stress up line was estimated between 3.3 and 4.2 . In the period of stress, the CWSI index was calculated and the amount of soil moisture was measured. According to the results, between soil moisture and CWSI index values, the inverse relationship was established with good correlation. Therefore, regression models with linear, exponential, logarithmic, polynomial and power forms were fitted between the above (two) parameters. The best and worst models for estimating soil moisture were the polynomial ( :0.987) and the power ( :0.65) models, respectively. The results showed that the critical values of CWSI index (at the time of increasing leaf surface temperature compared to air temperature), determined the irrigation time. Also, by indirectly estimating the amount of soil moisture, was calculated the soil moisture deficiency and water requirements for irrigation.

Due to the urban expansion, preparing of comprehensive and detailed information, is an unavoidable necessity for urban watershed systems and also its dominant conditions in hydrological cycle to gain an integrated urban watershed management. The urban runoff pollution caused by heavy metals is the major types of pollutions in surface runoff which may cause serious health risks for biosphere and also urban watersheds. This article examines the changes in runoff quality and the amount of heavy metals such as lead, zinc and copper in Bojnoord urban watershed in two reaches of autumn and spring seasons. For this reason 52 samples were collected for the mentioned period. After preparing the samples, using atomic absorption, the amount of heavy metals were measured in terms of Pbb. The results showed that the reducing trend of these metals is as Zn>Cu>Pb and the maximum concentration of lead, zinc and copper is related to the autumn season. The location of high concentrations is in residential and commercial areas and for the samples taken from the runoff pathways and drainage network (FB2). The Pearson correlation test results showed that there is a high positive correlation between lead and copper in the autumn (R=0.954) and also between lead and zinc in the spring (R=0.641). This correlation is certified by using factor analysis and Varimax rotation.

Groundwater is one of the important sources of drinking water and agriculture in the northern regions of the country. Population increases and demand for agricultural products, especially rice, in the northern parts of the country have increased the utilization of water resources in the past decade. The aim of this study is investigation of Sari plain aquifer vulnerability using SI model and the qualitative changes of water resources using Mann-Kendall test and age slope diagram for the total cations and anions, TDS, EC, pH and SAR of 38 operation wells registered in Mazandaran province. Firstly, the changes of qualitative parameters were investigated from 2006 to 2018. Then, the maps of SI model parameters (groundwater depth, net recharge, aquifer media, topography and land use) rated and the weight map of each parameter was obtained. The results of Mann-Kendall test and age slope diagram showed that the P-value of SAR variable is significant but total cations and pH is less than 0.05. The coefficient of determination (R2) showed that the total cations, SAR and pH with values of 0.272, 0.249 and 0.235 have most related to the qualitative changes of groundwater resources in Sari plain. The age slope diagram also showed an ascending trend of the parameters. Finally, with the overlap of SI model parameters, most of the areas with moderate vulnerability risk (50.92) included the highest percentage of area. Validation results showed that, 57.19 percent and 0.67 percent of area has moderate and lowest overlap respectively.

Population growth and urbanization are the main reasons for increased pollution nowadays. Pollution entrance into urban drinking water distribution networks, can cause irreparable damage to human health as a result of the suction phenomenon. Awareness and understanding of pollutant sources and the process of contamination transport in the water network leads to advancements in the development of suitable modeling of this phenomenon, as well as, enabling proper crisis management, when the contaminants enter the network. In order to simulate the movement of nitrate in the soil, the nitrate advection-dispersion equation was programmed in MATLAB. The second zone of water distribution network of Zahedan has been considered as the study area and potential points with high concentration of pollutants in the network have been identified. Network simulation, after two hours of contamination, was tested for water contamination by using EPANET software. To manage the network pollution crisis, two water quality management tools were used in the distribution network, including polluted water discharging and dilution flow, then their results were compared in the crisis management. The results of simulating the movement of pollutants in the soil demonstrated that nitrate concentration near the pipe is unallowable and greater than 50 mg/l. The results of discharging of the polluted water showed that by closing pipes from 1.1 to 1.3 of the pollution injection time and also discharging water from 5 to 8% of the base pipe flow can prevent the pollution from entering   other parts of the network. Moreover, For the first time, efficiency and positive performance of dilution flow as another tool for quality management of water distribution network was proved. The Required dilution flow to treat the quality of water was determined to be approximately 16% of the base pipe flow. In order to manage the pollution crisis in the water distribution network, it is vital to use these valuable tools in different situations.