Iranian Journal of Irrigation and Drainage
Year:2022 | Volume:16 | Issue:4|Papers Count:15

Irrigation Researchers have recommended changing water delivery methods from rotational to on-request methods to enhance flexibility. The diversity of requests in the on-request method makes it difficult to plan and implement the water distribution. The intensified unsteady flow is a challenge concerning the hydraulic performance and flexibility of canals. Flow instability may be associated with excess or deficiency of water delivery, leading to poor performance contrary to the initial intention. Thus, the hydraulic performance of various on-request methods needs to be assessed before recommending them. In this research, based on the classification of on-request methods three options are defined. To facilitate the evaluation of different options identical volume of water is delivered to the turnouts during the irrigation cycle in all delivery rotations. To this end, out of the three delivery factors of flow rate, duration, and frequency, two factors are considered to be variable. An overall of 14 scenarios was defined by separating the conditions for increasing and decreasing demands. The scenarios were simulated and evaluated in the East Aghili canal using ICSS model. The results show that, even though with increasing the flexibility, unsteady flow behavior is increased, however, if the structures are adjusted accurately, the hydraulic performance of the canal would not be much different. The maximum deviation of water delivery to turnouts among scenarios is about 3% by volume. The lowest values of Adequacy and Efficiency indexes of water delivery are equal to: 0. 970 and 0. 968, respectively, and the highest values of Equity and Dependability indexes are 0. 082 and 0. 056, respectively, which shows that all of them are very close to their ideal values. Hence, regardless of the hydraulic behavior of the flow, different levels of flexibility can be achieved for a variety of on-request methods by correctly determining and performing the operation instructions.

Water scarcity has become one of the important global challenges. The importance of water supply and demand management solutions is increasing every day. The present study was done using the SWOT analysis method for strategic analyzing water productivity and for providing water supply and demand management solutions in the Qazvin irrigation network. Data were collected through documentary-based research, metaanalysis, and field visits. The statistical population included water experts in Qazvin province and the sampling method was purposive sampling. In data analysis, the mean index, standard deviation index, Kolmogorov and Smirnov tests, one-sample t-test, and one-sample sign-test were used. 13 strengths, 21 weaknesses, 17 opportunities, and 9 threats were identified. The overall average strengths, weaknesses, opportunities, and threats were 3. 44±, 0. 86, 3. 80±, 0. 80, 3. 00±, 0. 83, and 4. 08±, 0. 86, respectively (out of a total score of 5). Overall feasibility for the strategies in terms of financial, institutional and organizational, social, environmental, and technical dimensions was 5. 29, 4. 64, 5. 47, 8. 77, and 7. 60, respectively (out of a total score of 10). The main bottlenecks of water productivity improvement are institutional, financial, and social fields. In this research, 31 initiation, mediation, and termination strategies were presented in the form of a strategic route map for improving water productivity.

For a long time, the Sistan Plain has been one of the important areas for men’, s settlement due to abundant water resources. Following the preparation of the archaeological map of Iran and in methodical surveys of the Sistan plain, settlements of the era were identified and their geographical location was recorded. So far no comprehensive study on relation between water resources and settlements has been conducted. The present survey aims for studying reciprocal relation between Sassanid settlements and natural environment in areas based on water component. This research has been carried out through the descriptive-analytical and historical method using GIS software. To reach the research goals after environmental conditions had been studied, six variables including water resources types, distance from water resources, land slope, soil type, Geology and settlements area were studied and results indicate surface water resources effective role in settlements placement and settlements area. Locating on delta fans would lead to change of direction branching canals of rivers, which causes numerous relocations of settlements. The Water resources existence, gentle land slope and consequently ease of water flow down to different areas of plain, branching canals creation capacity to keep the suitable distance to river and also, placement on the alluvial terrace to avoid flood hazards are among the factors turned the area to population absorbing one despite shortage of aquifers and people’, s heavy reliance on surface water resources.

Sensitivity analysis is an essential step before calibrating crop models. It helps researchers to have enough information about the effectiveness of each parameter and changes them during the calibration stage. This issue is more critical due to the increasing use of the AquaCrop model for crop simulation. Therefore, in the study, the sensitivity of AquaCrop to change some crop growth parameters,normalized water productivity (WP*), maximum transpiration coefficient (KCTrx), initial canopy cover (CC0), canopy growth coefficient (CGC), canopy decline coefficient (CDC) and harvest index (HI) were assessed using Beven (1979) method. For this purpose, the data collected in a research farm in Ahvaz were used. The studied treatments include irrigation methods (D: sprinkler irrigation using saline water, F: Sprinkler irrigation using saline water with post-irrigation with nonsaline water to wash the leaves, and S: furrow irrigation using saline water) with five irrigation water qualities (S1: 2. 5, S2: 2. 3, S3: 3. 9, S4: 4. 6 and S5: 1. 5 dS m-1). The results showed that the highest sensitivity was to changes in normalized water productivity (0. 95≤, Spi≤, 1. 04) and maximum transpiration coefficient (0. 95≤, Spi≤, 0. 67). After that, the sensitivity of the harvest index (0. 51≤, Spi≤, 0. 56) was in the middle category. The range of yield changes in different values of normalized water productivity, maximum transpiration coefficient, harvest index, and canopy decline coefficient was 1. 3-3. 3, 0. 8-1. 6, 0. 6-1. 16, and 0. 32-0. 64 ton ha-1, respectively. Sensitivity coefficients were positive for all parameters except CDC. Therefore, by increasing the CDC, AquaCrop suffers from underestimation error (between 17-33%), and by increasing the value of other parameters,the model suffers from overestimation error (between 5-70%). Therefore, in situations where the difference between observed and simulated yield is significant, it is better to consider the parameters of normalized water productivity and maximum transpiration coefficient. Otherwise, the parameters of the harvest index and canopy decline coefficient should be considered.

Sliding valves are among the hydraulic structures that have many applications in irrigation and drainage and dam networks. Their most important application is to increase the water level in order to drain the upstream canals and increase the height of the dam weir in order to store more water and also to measure the flow discharge. Many researches have been done to determine the flow coefficient (Cd) of these valves, all of which have been for valves perpendicular to the channel axis. In this research, the data of the hydraulic model of the side sliding gate of the sharp edge of the hydraulic laboratory of the Faculty of Civil Engineering, Rourke University of India have been used, which includes 121 laboratory data related to the free flow regime with three valve width to flume width ratios of 0. 60, 0. 83, 1. 00 and the flow discharge is 25 to 120 liters per second and 80 laboratory data are related to the submerged flow regime with a ratio of valve width to flume width of 1 meter and flow range of 25 to 85 liters per second. Laboratory data include flow rates Q, water depth before valve y1, flow depth at the bottom yt and opening of valve a. Using the analytical method and dimensionless number a / y1, the critical depth value under the sliding valve ycs For free flow regime and immersion coefficient ,For submerged flow regime, the amount of flow discharge was calculated directly. The results of validation of the extracted relationships show that the use of the critical depth parameter in determining the amount of flow discharge has a high accuracy.

In order to investigate the effect of changes in irrigation cycle on yield and its components, water use efficiency, economic index of water use efficiency and net income of Zataria multiflora, experimental in 2016-2017 crop year, in randomized complete blocks with four levels of irrigation cycle (4, 8, 12 and 16 days), in three replications, using T-TAPE irrigation system in Aliabad region of Fars. The results showed that the effect of 8-day irrigation period was significant at 1% level on fresh and dry weight yield of the plant, number of lateral branches, amount of active ingredient and harvest index and had no significant effect on plant height. The value of the final production index in relation to the depth of irrigation water for minimum irrigation (17. 46 cm) is equal to 180. 33 kg per cm of water and for maximum irrigation (75. 66 cm) is equal to 41. 61 kg per cm Water came in handy. The results showed that the 8-day treatment had the maximum amount of water consumption efficiency and in the 8-day treatment the values of economic index of water consumption and net income were 3 and 1. 5 times higher than the executive treatment in the region (4-day cycle), respectively. During 12 and 16-day irrigation periods, plant yield was significantly reduced due to severe water stress. According to Stewart model, the sensitivity coefficient of the plant was calculated to be 0. 69. Therefore, considering the resistance and yield and capacity of thyme plant to increase the irrigation cycle in the region, the use of 8-day irrigation cycle is recommended in terms of quantity, quality and economy.

In this study, a special type of sharp-crested weir is called sharp-crested morning glory weir (SCMGW) is introduced. Due to the special shape of this weir, high measurement accuracy in low discharge, and in flood and sudden discharges, less back water profile is expected upstream. On the other hand, there is no discontinuity in their stage-discharge relationship. Assuming the occurrence of a critical flow in the weir crest, the general stagedischarge relationship was extracted for this type of weir. The next step was to correct this assumption, considering that the assumption of the occurrence of a critical flow in the weir crest is accompanied by an error, and consequently the stage-discharge relationship obtained based on this assumption is not accurate. For this purpose, by measuring 57 experiments on 5 types of this weir, the stage-discharge relationship was extracted and it was shown that for a specific stage, the measured flow is greater than the calculated analytical flow. A correction coefficient was applied to the analytical relation with the aim of matching the stage-discharge analytic relationship with the measurement. This correction factor was optimized and extracted using the gene expression programming method as a function of the weir height-to-head ratio (p / H) and the / n ratio (a and n parameters of the weir geometric shape). The results showed that the modified discharge-stage relationship estimated the measured discharge values as R2 = 0. 98, mean absolute error MAE = 0. 442 liters and root mean square error of RMSE = 0. 08 liters.

Groundwater management requires accurate quantitative and qualitative monitoring of groundwater with proper spatial and temporal distribution. Minimizing the number of monitoring wells with maximum spatial distribution for making it economical to monitor groundwater systems is required by managers. Therefore, the structure of groundwater monitoring networks and the number of required wells becomes an engineering optimization problem. The purpose of this study is to find candidates for optimal monitoring network with the least number of wells that provide sufficient coverage to identify groundwater quality in an area. Hence, the excess wells in the network are identified. The meta-heuristic Tabu search algorithm has been used in this research. The objective function in this study consists of two conflicting goals. The first goal is the maximization of the match between the interpolated groundwater quality index distributions obtained using data from all wells and the wells from newly-generated network. The Nash-Sutcliffe model was utilized as a criterion to evaluate this compliance. In this study, groundwater quality is expressed using a water quality index, including nine quality parameters. The second goal is to minimize the number of monitoring wells selected to save on monitoring costs. The two mentioned goals are summed up in a function using a weight coefficient that determines the importance of the goals compared to each other. The mentioned model was used for a number of different active wells. Also, using the Tabu search algorithm, the best combination of different active wells that achieves the maximum objective function was identified. Optimal networks suggest managers and decision makers to choose the optimal network to monitor water quality according to the accepted budget and error. Consequently, this optimizing model could reduce the number of monitoring wells by 34-75%.

Rainfall forecasting is important in many different aspects of watershed management, such as flood and drought warning systems. Spatiotemporal variations of rainfall cause its prediction to be difficult. In this study, the monthly rainfall of Urmia and Mako stations were assessed using the intelligent kernel-based methods using Ensemble Empirical Mode Decomposition (EEMD) and Wavelet Transform (DWT). For this aim, different models were developed based on teleconnection patterns and climatic elements including rainfall, humidity, and temperature of previous months, and the impact of these parameters on accuracy of the modeling process was investigated. The obtained results showed the high efficiency of the integrated methods used in modeling process. It was observed that in the monthly precipitation modeling, the simultaneous use of teleconnection patterns and climatic elements related to previous months improves the accuracy of the models by up to 35%. Comparison of the wavelet transform and ensemble empirical mode decomposition showed that time series decomposition based on wavelet transform led to more accurate outcomes. The results of sensitivity analysis showed that the precipitation parameter with three months lag was the most effective parameter in monthly precipitation modeling.

It is necessary to study the spatial-temporal trend of drought, which affects agriculture and food supply with its slow process and Multiple generating factors,Therefore, the present study was conducted to assess agricultural drought in Kermanshah using satellite indicators (Average images of Sentinel2 and Landsat8 satellites during the growing season) and terrestrial (using rainfall and temperature data from 1990 to 2020). The results of terrestrial indicators the absence of drought in 2002, 2007, 2018 and 2019. The 12-month and 24-month SPEI of 2001 and the 24-month SPI estimated 1999 in the category of very severe drought. Satellite indicators in 2015 and 2017 increased the Land Surface Temperature and in 2019 (increasing soil surface moisture and Temperature Vegetation Dryness) and 2020 estimated vegetation density. The decrease in sugar beet yield in the years 1999 to 2003 and the increase in the years 2006 to 2009, 2012/2011 and 2021/2020 confirm the high results. In the north, northeastern and eastern regions,High temperature, low rainfall and low humidity have dried the soil and negatively affected the growth, health and density of plants, but the southern region has always been humid. The presence of drought during the study period and Sentinel II images were more sensitive to vegetation indicators.

Water quality indicators are a standard for classifying surface water based on the use of standard parameters and are a mathematical tool that converts a large amount of data used to describe water properties into a number and obtains a water quality level. This study aimed to assess and compare the sensitivity of NSFWQI and IRWQISC water quality indicators to quality parameters using variance-based methods on Haraz River with monthly sampling in 2022 in 7 selected stations in the range of Panjab to Haraz Reservoir Dam in the province Mazandaran. The results of the present study have shown that the water quality in S1 (upstream) and S2-1 stations are relatively good at best, and bad at worst. Water quality in stations of S2, S3, S4, S5-1, and S5 (downstream), in the best case, is moderate and in the worst case in September has poor quality. SRC method was used to analyze the uncertainty and sensitivity of the NSFWQI index and FAST and SOBOL methodologies were used for the IRWQISC index. The results of sensitivity analysis based on the Factor Prioritization approach showed that in NSFWQI index, DO, BOD, CF, T, and P parameters respectively and in IRWQISC index after DO parameter, BOD, P, and N parameters had the most impact on output. In the uncertainty analysis, the results of applying the SOBOL methodology for different stations of Haraz River were consistent with the FAST method, but the results of sensitivity analysis obtained from these two methods were different from each other. Considering the obtained results and despite the similarity of the results of the two methods, it can be said that the SOBOL methodology has been more successful than the FAST methodology in this study due to unconditional convergence.

This study was conducted with the aim of field measurement of water productivity and applied water in barley farms in Markazi province. For this purpose, 26 farms in the major barley production zones in the 1399-1400 crop year, in Markazi province were. The farms were selected in coordination with the service centers and management of Jihad Keshavarzi, and the volume of applied water was measured without interfering with the farmers' irrigation program. In this regard, first the amount of water source discharge (canal, well, aqueduct or spring) was measured with a suitable device (flume and meter) in each of the selected farms. After that, by carefully monitoring the farm irrigation program, including the time of each irrigation, the number of irrigations per year and also measuring the cultivated area, the applied volume water used for each of the selected farms during the growing season was determined. The results showed that the volume of irrigation water for barley fields in the Markazi province varied depending on the irrigation method, irrigation period and field management and its volume varied from 3783 to 7232 cubic meters per hectare. The efficiency of irrigation water application in the studied farms varied from 51 to 100% and its average was 73%. Water use productivity for this crop in Markazi province fluctuated between 0. 43 to 1. 19 with an average of 0. 75 kg/m3. In general, the results of measurements performed in Markazi province show that regardless of the irrigation method used, irrigation management by the farmer has an important role in the amount of water used in the study fields. The results show the superiority of drip irrigation method over surface and sprinkler irrigation in the barley production in Markazi province. Also, the results of this study showed that there is the ability to implement deficit irrigation in the province's barley fields, so promoting and training deficit irrigation in a correct and practical way to farmers can significantly increase water productivity in the barley production.

The current study was conducted to investigate the yield, yield gross income and water and nitrogen efficiency of sesame cultivars grown under full and deficit irrigation conditions. The experiment was carried out at Seed and Plant Iprovement Research Institute, Karaj, Iran in 2017 and 2018. A randomized complete block design arranged in split-factorial plots with three replications was used to run the experiment. Irrigation treatments at two levels including deficit irrigation and full irrigation were assigned to the main plots and a combination of nitrogen fertilizer (0, 60 and 120 kg N ha-1) and sesame cultivars were allocated to sub-plots. To measure the efficiency of the inputs, the yield gross income and physical and economic efficiency indicators were used. According to the results, the average gross income of sesame production in the experimental years was 63. 3 million Rials per hectare and under full and deficit irrigation regimes the average gross income values were 94. 1 and 33 million Rials per hectare, respectively. The average water physical efficiency under full and deficit irrigation treatment was 0. 27 and 0. 18 kg of product per cubic meter of water, respectively, and the average nitrogen fertilizer physical efficiency under full and deficit irrigation treatment was 18. 8 and 6. 56 kg per kg of fertilizer. In addition, the average water economic efficiency under full and deficit irrigation treatment was 21336 and 14224 Rials per cubic meter of water, respectively. The results showed that with a 50% reduction in water consumption, the gross income of sesame production decreases to one-third. In contrast, choosing the right cultivar due to the availability of water increased sesame production by 66%. According to the results, it is suggested to select cultivars that have high yield and economic efficiency.

The current limitations in water resources necessitate the adoption of strategies to increase water use efficiency (WUE) and improve the active ingredients of medicinal plants, which requires increasing WUE to produce more crops per unit of consumed water. A method to increase WUE is to apply deficit irrigation (DI) management based on the identification of stress consequences. The effect of different DI methods on the growth and physiological properties of peppermint was investigated in a completely randomized experimental design based on potted planting with three replications in the research greenhouse of Ferdowsi University in 2017-2018. DI treatments were Full Irrigation (FI), DI 50%, Fixed Partial Rootzone Drying (FPRD), and Alternate Partial Rootzone Drying (APRD). The results indicated that the highest (173) and the lowest (140) numbers of leaves belonged to FI and (DI 50%) treatments, respectively. DI 50% and FI treatments presented the highest (39. 3 mmol/m2/s) and the lowest (31. 3 mmol/m2/s) values of stomatal conductance. The highest values of greenness index (GI, 53. 7), electrolyte leakage (48. 27%), relative water content (RWC, 55. 3%), essential oil (1. 58%), and proline content (2. 50 mg/l) were obtained in the FPRD treatment. The lowest corresponding values of GI (41. 5), electrolyte leakage (35. 72%), essential oil (1. 14%), and proline content (1. 23 mg/l) were recorded in the FI treatment. Essential oil yield was uppermost in the FI treatment and no significant difference was detected in the other treatments. Altogether, given the water crisis in Iran and the reduced yield of the active ingredients of the plant, the APRD treatment is recommended for the irrigation of this plant in greenhouse conditions.

In groundwater modeling, to input the hydraulic conductivity parameter, the aquifer is usually divided into some zones and for each zone a value is considered for this parameter. However, the field measurements of this parameter are performed only in some places, and therefore its generalization to other areas is associated with uncertainty. The aim of this study was to investigate the uncertainty of the hydraulic conductivity parameter in modeling the aquifer of Qom plain. For this purpose, using the MODFLOW groundwater model, the model of this aquifer was constructed and calibrated in a steady state simulation with a value of RMSE = 2. 95 m for computed groundwater levels. Then the model was run using Null Space Monte Carlo to identify areas of hydraulic conductivity that calibrate the model with the same error rate as the original model. The results showed that there are eight other different zones of hydraulic conductivity that if used, the model will still be calibrated with the same error rate. The highest standard deviation of the hydraulic conductivity parameter for these eight zones was about 28 meters per day in the central and northern areas of the aquifer and the lowest standard deviation was less than 1 meter per day that occurred in the southern and eastern areas of the aquifer. This means high uncertainty of the hydraulic conductivity parameter in the central and northern areas and less uncertainty in the southern and eastern areas. Given that no significant relationship was found between the amount of uncertainties of hydraulic conductivity and the location of piezometers, so it can be concluded that increasing the number of piezometers in the model does not help to reduce the uncertainties of the hydraulic conductivity parameter and therefore more measurements of this parameter in different parts of the aquifer is needed.