مجله آبیاری و زهکشی ایران
سال هفدهم شماره 6 (بهمن و اسفند 1402)

Irrigation efficiency is one of the important and common indicators in water consumption management, which has been used for a long time by researchers and irrigation experts to design and evaluation of irrigation systems. This index is defined by the ratio of water consumed by crops to water diverted from a source. It is a relative quantity that has the components of conveyance, distribution and application efficiency (the ratio of water used by plant to water used in the field). This research aims to evaluate irrigation efficiencies in Iran and its trends over time. The results of researches and studies conducted in Iran during the past decades have been collected and analyzed. To do this, two databases, including the irrigation efficiency database (Abbasi et al., 2015) containing 1900 efficiency data published in 1991-2015 and the database related to the results of the irrigation applied water and water productivity project made from 2016 to 2020. Results showed that the general trend of changes in irrigation efficiency in Iran has been positive and increasing. So that the average application efficiency, conveyance and distribution and total irrigation efficiency were 74, 77 and 57%, respectively. The total irrigation efficiency in Iran is more than the total irrigation efficiency in developing countries and close to the efficiency in developed countries. The analysis and evaluation of the irrigation efficiency over time showed that part of the achievement related to the irrigation efficiency is due to the management and infrastructure measures carried out by the trustees and part is due to the deficit irrigation in fields and gardens due to the physical shortage of water resources. So, the latter case is a serious threat to soil resources and it is necessary to proper measures to control salinity and further destruction of soil resources in the future.

The use of treated wastewater is considered as a solution for supplying water to green spaces. The reuse of purified urban wastewater in the irrigation of fields and green space can reduce the need to extract water from natural sources and also reduce the discharge of wastewater into the environment. In using treated wastewater instead of water, its quality and reaction with soil is important, and its long-term effects on the irrigation system, soil salinity, product yield and its quality, water-soil characteristics, and environmental effects should be considered. In arid and semi-arid regions, due to less use of water, higher evaporation and lower purification, the concentration of chemical substances in treated wastewater is higher. In the current research study, while checking the daily quality of the effluent from the Chehelbaze treatment plant in Mashhad in a period of 23 months, the possibility of using urban wastewater for irrigation of green spaces with the activated sludge treatment method was investigated. By determining the average amount of biological oxygen demand BOD 6.08 and chemical oxygen demand COD 13.70 and average TSS 3.05, removal of coliform and parasitic nematodes, the average ratio of COD to BOD purification 2.29, the quality status is within the permissible range of Green space irrigation was standardized. According to the examination of qualitative parameters and chemical compounds in terms of average BOD, COD and TSS and microbial parameters, the effluent of this treatment plant can be used in urban green space irrigation.

Evapotranspiration (ET) as a major component of the hydrological cycle and an important variable in the calculation of the earth's surface water and energy balance has a key role in agricultural water management. Under limited meteorological data, ET estimations using empirical models are less accurate and require adjustments based on water balance approach or lysimetric measurements. Combining ground observations with remote sensing information (such as satellite images) can improve the accuracy of these estimations. In this study, SENTINEL-2 satellite products were used to estimate actual evapotranspiration values in 8 stations of the Gorganrud-Gharehsoo basin, north of Iran, during the period 2016 to 2018. Considering the number of required images and significate variations of ET during warm season, a four months period of April to June was selected for comparisons. The Penman Monteith equation estimations using observed data of study stations was chosen as an evaluation metric of satellite products.Comparisons were evaluated using statistical indices of R2, RMSE. The coefficient of determination (R2) values between Penman-Monteith equation (PM) estimations and SENTINEL-2 outputs for the study stations of Rezvan, Bandar Turkman, Aliabad-e-katol, Gonbadkavos, Kalaleh, Gorgan, Gorgan Hashem-Abad, and Minoodasht, were 0.95, 0.76, 0.86, 0.87, 0.80, 0.86 and 0.84, respectively. The highest correlation of SENTINEL-2 and PM equation was obtained in Rezvan station (RMSE: 0.21, R2 = 0.95), while the lowest correlation was observed in Ghonbad kavoos stations, (RMSE = 0.37, R2 = 0.87). According to results, the SENTINEL-2 evapotranspiration estimations can be used in regions with in adequate observed data. The finer spatial resoulution of SENTINEL-2 improves the ET estimations accuracy. This satellite products may be recommended for regions with inadequate weather stations especially in semi arid regions

One of the ways to control floods in the rivers is to build rock-fill dams without clay core in the flow path. These dams reduce the peak flow of the passing flood and increase the flood evacuation time. In the current research in the laboratory flume, models of rock-fill dam with aggregates with an average diameter of 2 cm with lengths of 155, 165 and 175 cm in the flow direction were built with different slopes and 3 different flow rates were considered for each model. In each discharge, the depth of the footing of wall was changed using the control valve, for 5 different modes, and a total of 405 tests were performed. After performing the dimensional analysis, dimensionless quantities were extracted and then by applying multivariable nonlinear regression, which shows the objective function related to the discharge coefficient and dimensionless quantities. By performing a sensitivity analysis on the removal of dimensionless quantities, it was found that by removing the quantity the height of the dam to the depth of the water upstream, the absolute average of the relative error increased by 2.5%. While by removing the quantity (slope of the abutment of the dam), the absolute average of the relative error increased by 8.6%.the quantity the height of the dam to the depth of the water upstream, the absolute average of the relative error increased by 2.5%. While by removing the quantity (slope of the abutment of the dam), the absolute average of the relative error increased by 8.6%

The erosion and transfer of sediment caused by it affects the quality of surface water, and the estimation of sediment and flow quality plays an important role in the management of Water Resources. In the present study, modeling of quality and load indicators of flow sedimentation and providing relationships to predict the amount of flow sedimentation of Khorasan Razavi rivers in 6 stations and statistical period 1986 to 2016 with non-parametric and nonlinear methods of the gated recursive unit Network (GRU) and random forest algorithm (RF) were carried out. By using the bagging method, modeling of flow, sedimentation and total anion and Cation flow in both networks was modeled. MAE, MAPE and RMSE statistical indicators were used to evaluate the performance of the model and the R2 coefficient were used to evaluate the accuracy of data segmentation. Results of the average value of MAE, MAPE and RMSE indicators the water quality data of the stations examined in the GRU network is equal to 286.16, 0.06 and 1685.34 respectively and in the RF network is equal to 317.4, 0.08 and 1954.11 respectively and the sediment load data in the GRU network is equal to 200.95, 0.55 and 1434.44 respectively and in the RF network respectively equal to 52921.84, 0.90 and 1544.29 showed the superiority of the GRU model over the RF model in the modeling of sediment and water quality indicators of the Khorasan Razavi rivers.

Drought is a natural phenomenon that affects different climatic, hydrological and environmental systems. Drought modeling is an important issue because it is considered important and necessary in order to contain or reduce its effects and to preserve water resources and social management. In this research, by using multiple indicators based on MODIS and CHIRPS precipitation data set, to investigate the spatial and temporal characteristics, intensity and frequency of drought in Qazvin plain in a 20-year period in order to identify and describe drought based on different indicators. The results of the surveys based on the TCI index showed that in 2004 and 2020, about 63% and 76% of the plain is under the influence of moderate to severe drought, with the difference that the result of the VCI index survey in the same year The analyzed data show that only 54.1% and 67.3% of the affected area show similar drought intensity levels. Therefore, the TCI index has estimated relatively more drought stress than the VCI index. From 2014 onwards, the eastern and southeastern areas of the plain are gradually facing an increasing trend of drought, and in the years 2018 to 2020, drought has been faced with much greater intensity. In examining the correlation between different indices, the PDSI index has the highest correlation with the SPI-1 index with a numerical value of 0.74. Qazvin plain is currently exposed to drought due to climate changes and lack of proper productivity in the use and distribution of water resources. Therefore, it is recommended that continuous monitoring of drought and the use of early warning systems are effective in preventing the possible occurrence of severe drought events in the future and the possibility of implicit risks for Qazvin Plain.

Lack of water resources due to droughts and mismanagement of water consumption, has been paid more attention to provide effective solutions to increase water productivity, especially in the agricultural sector. One of the most important solutions in this regard is the use of soil moisture monitoring systems. In such systems, the performance efficiency of moisture sensors used in the soil possesses particular importance. In this study, moisture sensors based on fiberglass structures were designed and manufactured in 2021 and their performance was characterized. For this purpose, the sensors were designed in the form of porous blocks containing four types of fiberglass woven structures as membranes (P200 ،T281 ،P296 و P186). The results of statistical studies showed that P200, P296, T281 and P186 sensors had acceptable accuracy for estimating soil moisture, respectively. Based on RMSE the sensor equipped with P200 and P186 membrane had 0.05 and 0.065 error that were the lower and highest accuracy in measuring soil moisture. Also, the performance of the designed sensors in ten soil textures showed that the highest measurement accuracy was in medium to light soil texture. So that in P200 sensor the Sandy loam soil texture (with nRMSE=0.004), P186 sensor the Loam and Sandy Loam soil texture (with nRMSE=0.097-0.099), P296 sensor the Loam soil texture (with nRMSE=0.071) and T281 sensor the Silty Loam soil texture (with nRMSE=0.07) had the highest accuracy. The results showed that the type of membrane is effective on the efficiency of the sensor and the choice of membrane is suggested depending on the soil texture. Except P186 membrane, other membranes have acceptable accuracy and their low cost, ability to store and send soil moisture data to processing systems, recommend their use in smart irrigation system.

The development of the underground dams is essential in the water supply and storage for different climates especially desert areas, and can be great help. Geoelectric samples were carried out in Kahnouj Shah Strait in two stages and a total of 6 electric sondages with different distances in the area of the project. Then, the obtained data were processed using IPI2WIN software. After preparing geological, slope and land use maps in each region and combining them using Boolean logic, areas that are suitable for underground dam construction in terms of geology, slope and land use were identified in a combined map. According to the results of the geoelectric sondages and field evidences, the bed stone at the proposed option have dense clay and many salts, the impact depth on the bed stone has been measured at least 3 to 12.6 meters. The highest depth of alluvial was related to the sondage 185, and in spite of the alluvial terrace located on the northern bank of the river, the measurements depth in this section was only 4.7 meters that indicating the high bet stone in this section. Sondage 149 indicates the presence of wet alluvial layer near the earth's surface. The results of the samples show that the electrical resistance of different layers is mainly less than 30 ohm/m and the values above 60 ohm/m are seen rarely and only there are in the surface layers, which is due to fine grain texture and high density of sediments as well as water salinity. Due to the limitation of river bed width, high bed stone and also the presented materials regarding the limited permeability of alluvial sediments, it seems that there is no minimum condition for establishing a suitable reservoir for underground dam in this option.

Stepped spillways have received special attention today for their simultaneous operation in energy transfer and dissipation. In designing these spillways, the best way is to achieve a design with the highest amount of energy dissipation in the downstream and the lowest design cost. In this study, a multi-objective optimization model based on weed algorithms (IWO) and water cycle (WCA) is used to design stepped spillways with the aim of minimizing implementation costs and maximizing energy dissipation. The efficiency of the developed model was tested on the spillway of the down Siah Bisheh Dam. The results showed that the IWO algorithm has better accuracy and convergence speed than the WCA algorithm in solving the problem of multi-objective stepped spillway optimization. It was also found that using a multi-objective optimization approach can provide a set of answers to designers who can choose a suitable design for implementation in any situation depending on the amount of cost and energy consumption. Comparison between the responses with the lowest concreting volume provided by the IWO compared to the Spillway plan implemented, reduced the concreting volume by 20% and increased the energy dissipation by 12%. For the WCA, it also reduced the volume of concreting by 10 percent and increased energy dissipation by 4.89 percent.

Due to the reduction of quality and non-saline water resources, it is important to cultivate plants with high tolerance to environmental stresses such as salinity. The medicinal plant of hyssop grows easily in any soil without the need for food. This study with aimed at the response of different methods of hyssop plant planting to different levels of salinity was conducted as factorial experiment based on a completely randomized design with 3 replications, during 2020-2021 growing season in Salinity Research Center, Yazd. The experimental factors included three levels of salinity (0.44 [control], 3 and 6 dS/m), as the first factor and two cultivation methods (seedlings and seeds) as the second factor. The results showed that the highest plant height (44 cm) in control (with 167% more salinity than 6 dS/m) and seedling method (43% more than seed method), leaf area (764.51 cm2 with different 55.5% than 6dS/m) was obtained in control method. maximum total dry weight (0.86 g/plant) in control (115% more than 6 dS/m) and seedling method (60% more than seed method), maximum carotenoids content (3.25 mg/g FW with different 62% more than 6 dS/m) were observed in control when seedling method was used, also, at control and seedling cultivation treatment maximum total chlorophyll content (26.87 mg/g FW and 106% more than 6 dS/m) and highest amount of sodium (9486.83 mg/kg DW with increasing 216% than control treatment) in 6 dS/m, and also highest amount of potassium (21090.09 mg/kg DW with different 30% than 6dS/m) in control, were observed. In general, in the seedling planting method, compared to seed planting, the plant had more tolerance and adaptation as well as growth.

Maintaining food security in light of excessive depletion of limited unrenewable water resources, requires the authorities to make efficient use of water and energy as well as enhancing the productivity of these factors in every sector, particularly in agriculture. In this study, the volume of irrigation water supplied from tube wells with the same water level, seed yield, productivity of water as well as energy consumption for sunflower irrigated with drip tape and furrow methods under farmer’s management were recorded and analyzed. The measurements were made over 2020-2021 on 14 fields across Esfahan province where sunflower was a primary crop. Data from the irrigation systems were analyzed using t-test and Pearson correlation coefficients. Based on the results, the average volume of irrigation water for drip tape and furrow methods were 6272 and 7987 cubic meters per hectar, respectively; showing significant difference. Comparison between the water requirement and the volumes of irrigation water applied by the farmers indicated deficit irrigation in 13 out of the 14 fields. Average sunflower seed yield for drip tape and furrow irrigation methods were 1894 and 1781 kg ha-1, respectively. In addition, average water productivity for the said irrigation methods were 0.3 and 0.23 kg ha-1, respectively; where no significant difference was found for any of the two foregoing parameters. There were inverse correlations between the volume of irrigation water and both seed yield and water productivity of sunflower, which were insignificant and significant, respectively. There were direct and significant relations between the volume of irrigation water and both energy consumption and energy productivity. For drip tape and furrow irrigation methods, the average values for energy consumption were 44871 and 44345 MJh-1, respectively which were not different significantly; and the amounts of energy productivity were 0.042 and 0.045 kg MJ-1, respectively which were not different significantly.

Surface runoff is the main factor eroding soil which causes sheet and interrill erosion in gentle slopes. It started when water infiltration would be lower than rainfall intensity during rainfall event. Soil properties can vary amount and rate of surface runoff during rainfall. This study was carried out to investigate the role of soil properties in amount of surface runoff generation and its temporal variations in different soil textures. Eight soil textures placed in 1 m × 1.2 m plots were exposed under seven simulated rainfalls with 60 mm h-1 in intensity for 60 min. Runoff samples were collected for 5-min intervals during each event. Results indicated that various soil physicochemical properties are different among the soils. Surface runoff varied among the soils and the highest runoff (55.51 mm) was in clay, while sand didn’t produce any runoff during rainfall. Surface runoff production rate temporally increased during rainfall and reached to a pick after about 30-50 min. Time to pick was very short (30 min) in fine textured soils. The correlation analysis showed that surface runoff is significantly affected by sand, silt clay, bulk density, gravel, hydraulic conductivity, calcium carbonate, gypsum and ESP. With an increase in soil hydraulic conductivity, surface runoff was inversely differed. Linear regression analysis showed that sand percentage is the most important factor controlling surface runoff in semi-arid soils. Controlling surface runoff in the soils with lower percentage of sand as well as hydraulic conductivity is essential to prevent sheet and interrill erosion in semi-arid soils.

Considering the crisis of water resources and spatial distribution of fertile lands, in order to reduce water consumption and increase food security, it is necessary to use a suitable cultivation model. The purpose of this research is to achieve a suitable cultivation pattern using the method of determining virtual water exchanges in Kurdistan province. The data of this research during the 10-year statistical period (1389 to 1398) in Kurdistan province includes information on the cultivated area and yield of 22 garden crops, irrigation information, meteorological data, population, per capita consumption of food products and their prices, which are calculated in Microsoft Excel ( 2021) has been accepted. The indices related to water requirement values, total virtual water, green virtual water, blue virtual water and virtual water balance were calculated for all selected products. In addition, the lack of attention to the spatial distribution of horticultural crops increased the average virtual water by 26.75 cubic meters per kilogram in Kurdistan province. Virtual water includes 97.4% of the total virtual water for all products investigated in the province, which shows the dependence of the agricultural sector on irrigation in the region. In general, by adopting three indicators of total virtual water, unit value of water and the ratio of required water to available virtual water among the horticultural crops examined, the most suitable cultivation pattern for Kurdistan province in order of priorities is horticultural crops such as seed crops, cold-season crops It is dry, nucleated and grainy. Based on the results of this research, it is suggested to the provincial managers related to the issue that in order to reduce the pressure on the water resources of Kurdistan province and virtual water exchanges, instead of paying attention to the seeded and seeded

Evaporation and Transpiration (including soil water evaporation and transpiration in plants) account for about 60% of the annual atmospheric precipitation on the earth. This process is the backbone of the hydrological cycle and a key element in Water Resources Management and the agricultural sector. The Soil and Water Assessment Tool (SWAT) and the Surface Energy Balance Algorithm for Land (SEBAL) are specialized models that address this problem. A SEBAL model is a tool for estimating the spatial distribution of actual evaporation and transpiration using satellite images such as MODIS, and Landsat 8. Although Landsat 8 images have a higher Spatioal resolution than MODIS images (30 m vs. 1000 m), their Tempoural resolution is lower than that of MODIS images (every 16 days vs. every day). On the other hand, daily MODIS images may not always be usable because of problems such as cloudiness. In addition, the interpretation of numerous satellite images is very time-consuming. In the current study, the evaporation and transpiration values in the catchment area of Karun River were obtained in three dry, normal and wet years (2019, 2020, 2021) using the recalibrated SWAT model based on runoff and crop yield and the SEBAL algorithm. Then the results of the SEBAL algorithm and SWAT model were compared with each other based on the water year conditions. In the second stage of the research, the results of the SEBAL algorithm and the range of changes of the main parameters of this algorithm in the plains of Ahvaz-Mlathani and Al-Baji basins were presented according to the ground data and using the MODIS images from the Terra satellite with a suitable time resolution and OLI sensor from Landsat8 satellite, which has a good spatial resolution.

The irrigation system, as one of the main factors in the production of agricultural products, plays a significant role in improving crop yield and agricultural water productivity. It is natural that choosing the right type of irrigation system for each region and product is important. In the present study, we selected the best irrigation system in the agricultural lands of Hakkamabad, Tabriz City, from the Hierarchical Analysis Process (AHP) among all types of rain irrigation systems, including fixed classic, manual displacement, wheeled, pulley, central rotary, linear, and other systems. Local irrigation, including tip, drip, fogger, and low-pressure bubbler, and surface irrigation systems, including flood irrigation, spot irrigation, strip irrigation, mechanized leakage, and leakage, were used. In this study, technical, social, economic, operational, environmental, and agricultural tourism criteria were used to select the most appropriate irrigation system for the study area. The results of the hierarchical analysis process showed that among the selected criteria and sub-criteria, the agricultural tourism criterion and tourism attractiveness sub-criterion had the most influence, while the technical criterion and automation possibility sub-criterion had the least influence on choosing the type of irrigation system. In this study, the Kirti irrigation system, with a score of 6.53, was chosen as the best option for the study area. Among the rain irrigation methods, a fixed classical system with a score of 4.34 and, among local methods, a tip system with a score of 3.82 were considered as another option for agricultural lands in Hakkamabad, Tabriz City.

In this study, the environmental flow of the Sojasrood River (Yengikand station) at Zanjan province was calculated using the water quality )the so-called Q relationship) and M5 tree decision methods and then the results were compared with the four hydrological methods (Smakhtin, desktop reserve model, FDC shifting and single low flow indices (7Q10 and 7Q2). Evaluation of the hydrological methods showed that the FDC shifting method has the proper accuracy than other methods in determining the environmental flow of the Sojasrood River. Based on the FDC shifting method, the environmental flow (Environmental Management Class C) at Yengikand station was equal to 0.99 (m3/s), respectively, which is equal to 29/4% of MAR. The maximum value of environmental flow was obtained by the water quality method (1.48 m3/s, equal to 43.9% of MAR) and the minimum value of environmental flow was obtained by 7Q10 and 7Q2 method (0.26 m3/s, equal to 7.7% of MAR) while, the environmental flow was determined 1.11 m3/s (equal to 32.8% of MAR) based on the tree decision method. In sum, the tree decision method (M5) extracted the equations of flow duration curve and could properly determine the environmental flow and is able to provide the values of characteristic discharges of a river.