Iranian Journal of Irrigation and Drainage
Year:2021 | Volume:15 | Issue:2|Papers Count:19

Effects of different irrigation levels on yield, water consumption, water use efficiency and agronomic characteristics of cotton-wheat crop rotation system products under the conservation agriculture system were examined in the temperate zone of Khorasan Razavi. The study was conducted in agricultural and natural resources research station of Gonabad using split split plot based on a randomized complete block with three replications in 2015. This research with three factors: a-tillage method at three levels (no-till, conventional tillage and reduced tillage) b-Residue management at three levels (without residue, maintain 30 percent of the debris and keep 60% residue) c-different levels of water irrigation at three levels (50, 75 and 100% of irrigation water requirement). The tillage method was treated in the main plot, the residue management treatment in the sub-plot and the different levels of irrigation water in the sub-plots. In this study, the common and suitable cultivar of the region, called Khordad, was used and drip irrigation method was used as a tool for uniform distribution and accurate measurement of water. In this study, drip irrigation was used as a suitable tool for uniform distribution and accurate water measurement. The results showed that the highest grain yield of cotton wheat was obtained from treatment of conventional tillage with 60% residue and applying 75% of the irrigation water requirement as 3576 kg/ha that there was no statistically significant difference with treatment of no tillage with 60% residue and applying 75% of the irrigation water requirement as 2568 kg/ha. The highest water use efficiency of cotton was obtained from treatment of conventional tillage with 60% residue and %50 of the irrigation water requirement as 0. 58 kg/m3. Regarding the non-significant of reduction in cotton yield under 75% of the irrigation water requirement was compared to the control, and due to the increased in water use efficiency under 75% of the irrigation water requirement was compared to the control, if needed to save water consumption (Due to lack of water resources in the country) application of 75% irrigation water requirement for cotton is recommended in agricultural conservation conditions.

Leaching modeling in the conditions of non-uniformity leaching in soil profile is desalination challenges. The final salinity in the soil profile has different values in two dimensions of soil depth and distance from the drainage pipe. Therefore, estimation the salinity values in the soil profile requires two-dimensional modeling of leaching. In this research, the data required for modeling were prepared by soil profile leaching in a physical model with dimensions (height × width × length) of 1×0. 5×2 m. In this model, soil drainage conditions were created for half the distance between the two drains. The target of this study was to compare the relationships of one-dimensional (in soil depth) and two-dimensional (in soil depth and distance from drain) in leaching modeling. Regression models included linear, exponential, logarithmic, polynomial and power functions. The results showed that in one-dimensional modeling, the coefficientR2 for linear, exponential, logarithmic, polynomial and power functions were equal to 0. 392, 0. 557, 0. 404, 0. 406 and 0. 562, respectively. But in twodimensional modeling, it was equal to 0. 796, 0. 94, 0. 55, 0. 614 and 0. 587, respectively. Therefore, increasing the coefficient R2 in two-dimensional modeling, showed an increase in validity in leaching modeling. In evaluating two-dimensional models by terms of ME, RMSE, R2, Radj 2 and EF, were selected exponential and linear models as the optimal model, respectively. For leaching modeling in the soil profile between two drains, using the twodimensional model had better performance than the one-dimensional model.

Compound channels form the cross section of many rivers, especially in adjacent areas of residential and agricultural areas Investigation of hydraulic behavior of compound channels is of great importance in floodplain control and river management plans. In this study, by modeling a concrete compound channel with Ansys Fluent software using k-ε,turbulence model and VOF method, shear stress and average flow velocity in compound channel with divergent floodplains were determined for different divergence angles. Also, the boundary conditions for flow in the studied channel are defined as input mass flow rate, output limit as pressure outlet, solid boundaries as non-slip and rough wall and upper channel boundary as non-slip and rough wall. The modeling and comparison between the laboratory data and the results of the present study showed that the maximum velocity in the channel occurs with a divergence angle of 3 degrees and with increasing the divergence angle, the flow velocity also decreases. In addition to, maximum of shear stress in the compound channel occurs with a lower divergence angle,In other words, as the divergence angle of the floodplain increases, the amount of shear stress of the fluid also decreases, and the higher the divergence angle, the lower the velocity. Also, the maximum shear stress in the channel with a divergence angle of three degrees and the minimum shear stress in the divergence angle is 15 degrees.

Stochastic drainage of rainfed lands (due to its dependence on rainfall) led to the application of random variables and time series modeling in predicting the performance of drainage systems. The aim of this study was to investigate the potential of time-series models in predicting drainage water and soil salinity in rainfed farms of subsurface drainage in Ran Behshahr, Iran. First, Drainmod-S model was calibrated using measured data. Then, drainage water and soil salinity were simulated via the calibrated Drainmod-S model. The simulated outputs were used for evaluation of the results of the time-series models including AR, ARX, ARMA and ARMAX. The results showed that the ARMAX model with exogenous variables including daily value, precipitation during the previous days and average desired variables in the last two days was efficient in predicting soil and drainage water salinity, so that the absolute mean modeling error for soil surface salinity (0-50cm), soil subsurface salinity (50-100cm) and drainage water salinity was 4%, 0. 4% and 5%, respectively. Comparison between the selected times-series models and the calibrated Drainmod –, S model results indicated that the application of time-series models in predicting the performance of the subsurface drainage system was satisfactory. The coefficients of determination were 0. 75, 0. 63 and 0. 57 for for salinity of soil surface and subsurface layers and drainage water, respectively. The root mean squared errors for these variables were 2412. 6, 331. 8 and 1724. 6 mg/ L, respectively. According to the evaluation indicies, time series models were efficient in predicting soil and drainage water salinity.

In this study, optimization of location of sampling stations for water quality of river system using information entropy theory in Lavasanat and Tehran-Karaj catchments with 11 sampling stations for 12 water quality and quantity variables for a statistical period of 21 years has been considered. First, using the discrete transinformation entropy theory, a T-D diagram was drawn for each variable, which indicates the distance between stations and transinformation. Then, using analytical hierarchical process (AHP) method and according to water consumption for agriculture and drinking, the weight of all variables was determined using Expert Choice software. The optimal distance between monitoring stations was obtained based on the total weight of each qualitative variable at its optimal distance of 14. 1 km. Also, the optimal distance was calculated by fuzzy AHP method, which was 13. 83 km. Then different scenarios were performed to eliminate or increase the number of sampling stations. The results show the efficiency of discrete entropy theory in combination with multicriteria decision-making method in optimizing the number and distribution of water quality monitoring stations in river systems.

One of the most important factors in calculation of greenhouse crop water requirement is the accurate estimation of reference crop evapotranspiration. Numerous parameters affect the evapotranspiration rate of the reference crop,with the knowledge of the most important factor the simulation error will be reduced. Because of the differences among mathematical structure and underlying assumption of indirect reference crop evapotranspiration estimation methods, behavior of the response variable to changes in climatic parameters may become inconsistent. Therefore, it is mandatory to analyze the sensitivity as well as determining the influence of meteorological factors on reference crop evapotranspiration. In this study, the sensitivity of Penman-Monteith, Irmak, Copais and Valiantzas methods to changes in meteorological factors including maximum and minimum daily temperature, maximum and minimum relative humidity and short-wave radiation was analyzed in the research greenhouse of the College of Agriculture and Natural Resources of the University of Tehran, located in Karaj, Iran. Sensitivity coefficients were calculated by changing meteorological factors in the range of [20,-20] percent with 5% intervals. Results showed that in all methods, the internal radiation was the most influential variable in determining the reference crop evapotranspiration under greenhouse conditions. The obtained sensitivity coefficient for this variable in Penman-Monteith, Irmak, Copais and Valiantzas methods was equal to 0. 78, 0. 71, 0. 68 and 0. 63, respectively. In contrast, the least important climatic variable was the minimum humidity in Penman-Monteith, Copais and Valiantzas methods and the minimum temperature in Irmak method. The results also showed that Penman-Monteith is the most sensitive method to changes in meteorological factors. As a result, in case of using of Penman-Monteith method for reference crop evapotranspiration estimation in greenhouse conditions, ensuring the correct operation of measuring instruments and their accuracy is essential.

Growing population of the cities along with the desire for better welfare and health has increased the water demand. On the other hand, many cities are located in the arid and semi-arid regions with the low rainfall and renewable water resources. Therefore it causes the water crisis. Shiraz is one of the metropolises that is facing this problem and in the warm seasons of the year experiences the drop in water pressure and water outages. Increasing the water supply, regardless of demand management, will exacerbate the crisis. Water pricing has been also one of the most important concerns of policymakers in demand management. Given the importance of this issue and also the role of social interactions among the consumers and the neighboring community network on the water consumption behavior, the present study concentrates on providing an agent-based framework for examining the water demand and changes in consumption behavior (diffusion process). The model has been calibrated for domestic water consumption in Shiraz for the years 2005-2019. Price increase scenarios (for all or only part of the consumers) as well as granting free branches have been simulated for the years 2020-2032. The results show that small increases in water prices do not have significant effect on consumption and cooperative behavior trend. Also, giving free branching to some consumers will intensify non-cooperative behavior among other consumers and increase the consumption sharply.

The imbalance between water supply and demand in the country has challenged water resource management, especially in the agricultural sector. In this regard, international trade in agricultural products and the displacement of water in them, which is called virtual water, can be one of the ways of water management. In this research, the study of water ecology and virtual water indexes in rice and wheat production in Khuzestan province have been investigated. To estimate the net blue product requirement (CWR), the amount of vegetation factor (Kc) and root depth of products are used by the FAO standard software (CROPWAT. 8). An interview method and a questionnaire were used to obtain information from farmers in the area. For this purpose, 152 people were sampled by Cochran formula. The "top-down" method was used to calculate the ecological footprint of the region. In this method, the water ecological footprints of each area, including two components of internal water ecological footprint (WFi) and external water ecological footprint (WFe) were investigated. The results of the study and comparison of wheat and rice plants in different plains of Khuzestan province indicate the high potential of the province in producing wheat needed by the province and its excess export to the province. Also, the results showed that rice cultivation in Khuzestan province, except in very limited areas in Haftgel and Baghmalek parts, is not economical due to the high consumption of water. Therefore, in agricultural development plans, it is necessary to prevent the cultivation of rice.

In order to detect pollutants in water distribution systems, sensors are used which, in addition to detecting pollution, also provide useful information to identify the source of pollutants. This information is useful for finding a suitable solution for quality management of the distribution network. The purpose of this study is to determine four characteristics of the pollution source to the system by a simulator-optimizer approach with optimally allocating two sensors in EPANET Example 2. These characteristics are: the contaminant injection node, injection mass rate, injection starting time and injection duration time. EPANET and genetic algorithm were linked as the simulator and optimizer tools to achieve these goals, simultaneously. For this purpose, first ten different pollution events were generated randomly, then the best place to install sensors in the network for identifying the source of pollution was found. Moreover, the shortest time of detection was selected among fourteen different combinations with a contamination source identification likelihood equal to 90%. The results showed that by placing sensors in two nodes 15 and 27 of the benchmark problem, the highest contamination source identification likelihood equal to 90% and the minimum detection time equal to 58 minutes were achieved.

The aim of this study was to investigate the effect of jet and reverse slope on the characteristics of hydraulic jump. This study was performed inside a flume in the form of a rectangular channel 10 meters long and 30 cm wide. Free jet with flows of 2, 2. 5 and 3. 2 liters per second with the maximum displacement angle of the beginning of the jump and the angle without changing the beginning of the jump to the end of the hydraulic jump. The results showed that changes in the angle and flow rate of the jet reduce or increase the secondary depth, jump length, relative energy loss and shear stress force of the bed. Using a jet with a maximum angle and flow rate of 3. 2 liters per second with the lowest landing number Reverse flow and slope reduced the secondary depth ratio by about 56. 2% compared to the no-jet mode and smooth bed. Using a jet with a minimum angle and flow rate of 3. 2 liters per second and the maximum flow rate increased the secondary depth ratio relative to Jetless mode was smoothed. The results of this study show that at a certain angle from the jet to the hydraulic jump, there is no displacement in the jump, which was named as the inert angle, and by increasing the angle of the jet jump upwards, the hand jumps to It moves upstream and from one angle onwards the jump does not move upwards. This angle was named as the maximum displacement angle. Changes in the angle and flow rate of the jet reduce or increase the secondary depth, jump length, relative energy drop and stress force. The use of a jet with a maximum angle (138 degrees) and a flow rate of 3. 2 liters per second, the minimum number of landings (6. 64) and reverse slope reduces the ratio of the secondary depth to about 56. 2% relative to the state without jet and bed was smoothed. Using the jet with the minimum angle (78 degrees) and the flow rate of 3. 2 liters per second and the maximum number of landings (9. 62) flow increased the ratio of secondary depth by 15. 3 percent compared to the state without jet and smooth bed.

Optimal physical conditions are important for proper germination and improve growth and more crop yeild. In order to investigate the effect of conservation tillage methods on soil moisture retention capacity and yield of white dry bean (Dorsa variety), in rotation with barley, an experiment was carried out at the Markazi Agricultural and Natural Resources Research and education Center during 2017-2018, 2018-2019 and 2019-2020. The experiment was carried out in randomized block design with 3 replications. Treatments were included: 1-the conventional tillage method (the use of moldboard plow –,Disc), 2-Reduced tillage with chisel-packer, 3-No-tillage. The percentage of crop residues in the conventional tillage, reduced tillage and no tillage methods were 20, 50 and 90%, respectively. The results showed that the highest and the lowest yield was obtained in the reduced and no-tillage with 2869 and 2076 Kg/ha, respectively. The highest soil moisture conservation was observed in the no-tillage and reduced tillage. So that the amount of soil moisture moisture in the reduced tillage and no tillage on the fourth day after irrigation, were 1 and 1. 8 percent higher than the conventional method, respectively. The results showed that the use of the reduced tillage method compared to the conventional method in drip irrigation method without reducing crop yield leads to more soil moisture retention and thus helps to improve water efficiency in bean production. In general, based on the results, due to the low soil organic matter in the region, using reduced tillage method is a suitable option to conserve soil and water resources and increase water productivity in the bean production.

Population growth and increasing environmental problems have greatly increased the demand for irrigation water from parts of the world. Nanotechnology enables the products of sustainable agricultural products to be able to reduce the environment and provide the conditions for the production of new products. The aim of this study was to investigate the performance and utilization of water consumption under low irrigation regimes and silica nanoparticles. The present study was performed on lettuce plant (Vivian lettuce baby dance) in three water levels (75, 85 and 100 required for water plant) and three applied nanoparticle levels including 0, 50 and 100 mg/l as root feeding. Performed in three replications. This design was completed in the form of shredded strip cards with a basic block design. According to the results, the highest total yield parameter was recorded in I100F100 treatment equal to 87. 88 g / plant and the lowest amount was recorded in I85F50 treatment with 47 g / plant, respectively. Also, the highest biomass yield was recorded in I100F50 treatment which was equal to 61. 33 g / plant and the lowest biomass yield was reported in I75F100 treatment which was equal to 26 g / plant. I100F50 treatment with 20. 53 kg / m3 had the highest water consumption efficiency. The highest and lowest harvest indices in this study were 74. 68 and 52. 61%, respectively.

Iran's water situation has reached a critical level due to frequent droughts and over-abstraction of water resources. Therefore, dealing with the optimal allocation of water resources in these conditions is an important and vital issue. In the present study, the model of water resources allocation in critical conditions has been developed and the proposed model has been implemented in Mashhad. The innovation of the proposed model of the present study is to consider the sustainability of water resources and simultaneously pay attention to the quantity and quality of water resources. In this study, considering the stochastic value of available water parameter, two-stage stochastic allocation model is presented and solved by the method of Goal Attainment, and implemented in MATLAB software. This model has been developed with the aim of maximizing the profits of different users, minimizing the allocation of saline water from the underground source and minimizing the shortage of water. The results of the study indicate that even in the wet scenario, available water resources cannot meet the demand of different sectors. If the stability index is maintained at 75%, the amount of water shortage in the drought scenario is equivalent to 501. 75 MCM, in the normal scenario is equal to 358. 75 MCM, and the in the wet scenario is equal to 78. 75 MCM. In addition, the sensitivity analysis of the model with different data indicates that if in the drought scenario, the amount of available water from both surface and treated water sources is equivalent to 300 and 200 MCM, respectively, then the optimal allocation pattern has changed and the amount of water shortage that can lead to overdraft is 103. 75 MCM. In this study, considering the amount of water available parameter random, random allocation model proposed two-stage.

In the face of increasing urban wastewater and the fact that the country's water resources are not only limited but also declining, increasing water use efficiency and reuse of municipal wastewater is inevitable. This study was conducted to investigate the use of municipal wastewater on yield, yield components and water use efficiency in forage maize with two factors: a) Use of wastewater in three levels (1-well water (W), 2-One to one mixture of well water and wastewater (50 50) and 3-Wastewater (WW) b) Management of traditional low irrigation at four levels (normal irrigation (100% irrigation requirement)) and low irrigation at 40, 60 and 80% levels of water requirement) in the form of a randomized complete block design with 12 treatments and three replications in the field of Marvdasht municipal wastewater refinery plant in 2018. Statistical indicators such as maximum error, coefficient of determination, mean square root of the error, modeling efficiency and residual coefficient were used to quantitatively evaluate the functions. Plant susceptibility coefficient (Ky) for total dry matter in three stages of vegetation, flowering and grain ripening were 0. 38, 0. 52 and 0. 63, respectively, and it was found that the most sensitive stage of corn growth to water deficiency is the stage of grain ripening. Analysis of interactive effects showed that the highest total dry matter yield in vegetative and flowering stages and grain yield in grain growth stage were 7260, 9857 and 3158 kg/ha in WW-FI treatment (complete irrigation with wastewater) and the lowest yield with the values of 5052, 6069 and 1508 kg/ha were obtained in W-DI60 treatment (60% low irrigation with well water). The results showed that the use of wastewater in low traditional irrigation conditions is useful for forage maize and can be recommended.

Quinoa (Chenopodium quinoa Wild) is a nutritious herb with favorable nutrition and potential for suitable production in adverse environmental conditions that can withstand drought. This study aimed was to evaluate the effects of alternate furrow irrigation at its different growth stages on Quinoa yield and water use efficiency in the Ferdowsi University of Mashhad (FUM) experimental farm research during 2018-19. This research was conducted to completely block randomized design with seven treatments and three replications. In this study, 7 treatments consisted of traditional furrow irrigation (TFI), fixed alternate furrow irrigation (FAFI), variable alternate furrow irrigation (VAFI), fixed alternate furrow irrigation at the vegetative stage and traditional furrow irrigation at other stages (FTT), fixed alternate furrow irrigation at the vegetative and flowering stages and traditional furrow irrigation at other stages (FFT), variable alternate furrow irrigation at the vegetative stage and traditional furrow irrigation at other stages (VTT), variable alternate furrow irrigation at the vegetative and flowering stages and traditional furrow irrigation at other stages (VVT) treatment with supplemental irrigation in time of planting. The results showed that the effect of treatments on panicle length, stem diameter, plant height, panicle weights, grain yield, yield per m2, and water productivity were highly significant (P>0. 01) and panicle width was significant at the 5 % levels. Results showed that the highest yield (2. 17 ton/ha), grain yield (18. 1 g per plant), average plant height (113. 3 cm), and physical water productivity (0. 41 Kg/m3) were in TFI treatments. Used FAFI, FTT, FFT, VAFI, VTT, and VVT treatments compared to TFI, grain yield decreased by 35. 4, 24. 3, 32. 0, 23. 2, 13. 8, and 17. 7 percent, respectively. Used FAFI, FTT, and FFT treatments compared to TFI, physical water productivity decreased by 19. 5, 14. 6, and 2. 4 percent, respectively. Used VAFI, VTT, and VVT treatments compared to TFI, physical water productivity increased by 2. 4, 14. 6, and 24. 4 percent, respectively. Therefore, the best irrigation treatment for the Quinoa in the field conditions is VTT methods.

Determining groundwater changes in Iran, which is located in arid and semi-arid regions, is of particular importance. In this regard, Kermanshah province with 950, 000 hectares of agricultural land and gardens is one of the agricultural hubs of the country and the water level in the aquifers of the province, especially in the eastern part of the province is more severe. In this study, by examining the water level of the observational wells of Mianrahan aquifer in Jamishan basin and spatial zoning of these changes using Kriging method in GIS software, the current situation of the region has been investigated. In order to evaluate GRACE satellite data with JPL, GFS, CSR, CRI data centers, coding in Google Earth Engine cloud computing environment has been used. Monthly and annual changes of liquid water equivalent (LWE) were calculated. Comparing the results of different data centers show that JPL data center with coefficient of R = 0. 66 has the highest correlation with observational data. The amount of soil moisture, snow water equivalent and plant canopy water was extracted from the GLDAS model and subtracted from the amount of TWS extracted from the GRACE satellite and was compared with the observed values, which shows that the trend of decreasing groundwater level is equal to-2. 26 cm. Calculations are made on the scale of one square degree and units are expressed in centimeters.

In order to investigate the effect of different intervals and irrigation methods on the growth characteristics of canola, an experiment was conducted in the form of split strip plots based on a randomized complete block design with three replications during 2009-2010 at Hajiabad Agricultural Research Center. In this regard, three irrigation intervals including irrigation after 20, 40 and 60 mm of evaporation from the surface of the evaporation pan (I1, I2 and I3, respectively) and two drip irrigation methods (surface and subsurface) were considered as the main and secondary factors, respectively. The results indicated the lowest and highest yield (1. 97-3. 15 t ha-1), 1000-seed weight (3. 38-4. 82 g) and number of seeds per pod (14. 5-24. 5) at the I1 and I3 irrigation intervals, respectively. However, the I2 irrigation interval treatment resulted in a 9. 6% increase in water use efficiency compared to the I1 irrigation interval. Also, the use of subsurface drip irrigation compared to surface drip irrigation method increased crop yield, water use efficiency and number of pods per plant by 29. 8%, 32. 2% and 33. 1%, respectively. The findings of this study showed that in general, in case of water insufficiency in the study area, the irrigation cycle after 40 mm of evaporation from the pan applied in the subsurface drip irrigation method can be suggested as a superior treatment. With this approach, we can take steps to deal with the water crisis based on sustainable agriculture in canola cultivation in Hajiabad region.

Side weirs are important structures in irrigation and drainage networks that are used as a protective structure upstream of reverse siphons and road underpasses. In this research, using laboratory data, for two positions of lateral overflow placement diagonally in the width change wall and directly and in the wall without change width, a new relationship based on the critical depth of flow on the weir to determine the discharge discharge weir (QW) are provided in rectangular channels with narrowing downstream of the weir. The results showed that the discharge capacity of oblique weir decreasing width downstream is more than normal overflows and also diagonal weirs located in the width reduction wall are more than the case where the weir is in the direct wall without width reduction. Finally, by comparing the relationships obtained from dimensional analysis in two types of overflows, it can be concluded that the flow rate of side weirs located in the diagonal wall of the transition section is about 7. 50 percent higher than the case where the side is located in the direct wall of the weir. The reason is less interference of flow lines. Also, the narrowed part of the downstream acts as a barrier, increasing the depth of flow and less curvature of the flow lines, and the flow passes through this weir with less drop.

Providing efficient irrigation method and selecting the appropriate cultivar in order to increase yield and water use productivity can greatly contribute to the quantitative and qualitative production of peanut products. The present study was conducted to investigate the yield, production function and water use productivity of two peanut cultivars under deficit irrigation conditions in different irrigation methods in the form of conducted as split split plots in the form of a randomized complete block design with three replications in 2018 and 2019 in Guilan province. The main treatment consisted of two methods of drip and furrow irrigation, and the subtreatment included supplying 125, 100, 75, 50 and 25 percent of water requirement, and the sub-sub-treatment included two peanut cultivars Guil and Jonobi. The results showed that simple effects, Interaction between irrigation and water supply and the interaction of water supply and cultivar at the level of one percent on biologic yield, pods and seeds were significant. The pod and seed yield in the drip method was higher than the furrow method. Due to the interaction of water requirements supply and cultivar, the highest yield of biomass, pods and seeds with 100% water requirement supply was in Guil cultivar. In drip irrigation method and providing 100% of water requirement, the highest water use efficiency based on pod yield in the first and second year was 0. 91 and 0. 94 kg/m3, respectively, and in seed yield during two years was 0. 60 kg/m3 was obtained. Water supply was significant for seed oil, phosphorus and nitrogen content at 1% level and for seed protein content at 5% level. The highest content of oil, phosphorus and nitrogen was obtained with 100% water requirement, and in seed protein with 25% water requirement. Based on the results and considering the water use productivity, cultivation of peanut Guil cultivar using drip irrigation method and providing 100% of water requirement is suggested for the study area.