Irrigation
Seyed Abolghasem Haghayeghi Moghaddam; Fariborz Abbasi; Abolfazl Nasseri; Peyman Varjavand; Sayed Ebrahim Dehghanian; Mohammad Mehdi Ghasemi; Saloome Sepehri; Hassan Khosravi; Mohammad Karimi; Farzin Parchami-Araghi; Mustafa Goodarzi; Mokhtar Miranzadeh; Masoud Farzamnia; Afshin Uossef Gomrokchi; Moinedin Rezvani; Ramin Nikanfar; Seyed Hassan Mousavi fazl; Ali Ghadami Firouzabadi
Abstract
Introduction
The basic strategy to mitigate water crisis is to save agricultural water consumption by increasing productivity, which will result in more income for farmers and sustainable production. Due to the economic importance of barley production in the country, it is necessary to study the volume ...
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Introduction
The basic strategy to mitigate water crisis is to save agricultural water consumption by increasing productivity, which will result in more income for farmers and sustainable production. Due to the economic importance of barley production in the country, it is necessary to study the volume of irrigation water and water productivity to produce this strategic product. Based on extensive field research on irrigation water management and application of different irrigation methods in barley farms, the innovations of this research were: a) measuring water consumed and determining water use efficiency in barley production, b) the up-to-date of the measurements and research findings, c) findings applicability for application in agricultural planning at the national and regional levels, d) the ability to development the findings in barley farms at the national level to improve water use efficiency. The hypotheses of this research are: a) barley irrigation water is various in different regions, b) water applied in barley farms is more than the required one, c) the water use efficiency of barley is different in the main production areas, and d) The applied water of barley is not the same in different irrigation methods. Therefore, the main objective of this study is to determine the water consumed and water use efficiency in barley production; to measure the water applied to barley farms in the main production areas; to compare the water measured in the production areas with the net irrigation requirement; and finally to determine water use efficiency of the barley in the main production areas in the Iran.
Materials and Methods
For this purpose, the volume of irrigation water and barley yield in 296 selected farms in 12 provinces (about 75% of the area under cultivation and production of barley in Iran) including Khuzestan, East Azerbaijan, Ardabil, North Khorasan, Fars, Khorasan Razavi, Tehran, Semnan, Markazi, Isfahan, Hamedan and Qazvin were measured directly. Farms in the mentioned provinces were selected to cover various factors such as irrigation method, level of ownership, proper distribution and quality of irrigation water. By carefully monitoring the irrigation program of selected farms during the growing season, the amount of irrigation water for barley during one year was measured. At the end of the season and after determining the average yield of barley during the 2020-2021 year, the values of irrigation water productivity and total water productivity (irrigation+effective rainfall) were determined in selected barley farms in each region. The volume of water supplied was compared with the gross irrigation requirements estimated by the Penman-Monteith method using meteorological data from the last ten years, and compared with the values of the National Water Document. Analysis of variance was used to investigate the possible differences in yield, irrigation water and water productivity in barley production.
Results and Discussion
To assess the reliability of statistical analysis, we evaluated the sufficiency of the number of measurements needed for both the quantity of irrigation water and the ley yield on the farms. Subsequently, we computed statistical indices, such as the mean and standard deviation. The results showed that the number of measurements of irrigation water and barley yield was to be 296 and 283, respectively, which was more than the number of measurements required for irrigation water (41 dataset) and yield (50 dataset). Therefore, the sufficiency of the data for the statistical analysis was reliable. The results showed that the difference in yield, volume of irrigation water and water productivity indices were significant in the mentioned provinces. The volume of barley irrigation water in the studied areas varied from 1900 to 9300 cubic meters per hectare and its average weight was 4875 cubic meters per hectare. The average barley yield in selected farms varied from 1630 to 7050 kg ha-1 and the average was 3985 kg ha-1. Irrigation water productivity in selected provinces ranged from 0.22 to 1.53 and its weight average was 0.90 kg m-3. Average gross irrigation water requirement in the study areas by the Penman-Monteith method using meteorological data of the last ten years and the national water document were 4710 and 4950 cubic meters per hectare, respectively. Irrigation efficiency of barley fields in the country is estimated at 62-65% without deficit irrigation.
Conclusion
In order to reduce water consumption and improve water productivity, it is suggested to manage water delivery to farms during the season and deliver water rights to them according to crops water requirements. To reduce water losses and enhance productivity in the barley farms, it is suggested the application of modern irrigation systems according to the farms conditions with the suitable operation; and modification and improvement of surface and traditional irrigation methods. Note that, water is only one of several necessary and effective inputs in the optimal and economic production of barley. On the other hand, attention should be paid to the optimal application of other inputs including: seeds, fertilizers, equipment and tools etc.
Irrigation
S. JafarNodeh; A. Soltani; E. Soltani; A. Dadrasi; S. Rahban
Abstract
IntroductionAccurate knowledge of water balance components is necessary to optimize water consumption in agriculture. On the other hand, measuring water balance components is expensive and difficult. Therefore, the use of models that can simulate water balance values is important for water management ...
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IntroductionAccurate knowledge of water balance components is necessary to optimize water consumption in agriculture. On the other hand, measuring water balance components is expensive and difficult. Therefore, the use of models that can simulate water balance values is important for water management in agriculture and water used by plants. Crop simulation models have been turned into essential tools for studying plant production systems. In the SSM-iCrop2 models, it is presumed that diseases and weeds are optimally managed and will not affect growth and yield. Additionally, except in cases where the model accounts for specific nutrients such as nitrogen, it is generally assumed that nutrient deficiencies are eliminated through fertilization. Therefore, parameterized and evaluated models are designed to fit these conditions. These factors are present in the field and affect crop growth and yield as well as water use. However, in several cases it is required to estimate yield and water balance components and irrigation water volume under grower conditions. Naturally, models parameterized using experiments are unable to simulate these conditions. Therefore, a model must be prepared so that it can simulate the real conditions of farmers. In this study, the SSM-iCrop2 model has been calibrated for the real conditions of farmers, and the purpose of this study is to use the SSM-iCrop2 model in simulating water performance and water balance for farmers. Materials and MethodsIn this study, the SSM-iCrop2 model was calibrated for farmers conditions using variables such as yield and harvest index, which are available for farmers’fields or are cheap to measure. The effect of factors such as pests and diseases, weeds and unsuitable nutrients, density and sowing date entered the model along with the calibration of three parameters of radiation use efficiency, maximum leaf area and maximum harvest index for farmers’ fields. Calibration was done by comparing the performance of farmers against the performance simulated by the model and by changing the parameters of radiation use efficiency (IRUE), maximum leaf area (LAIMX) and maximum harvest index (HIMAX). This calibration was done at Hashem Abad station in Gorgan for irrigated rice (paddy) and wheat. The simulated actual yield was calibrated with the actual yield. Due to the acceptable simulation of actual yields after calibration, it was presumed that other estimates made by the model are also reliable. Results and DiscussionMeasurement of water balance and other estimates of the model from growth and yield formation in the grower fields is expensive, but a calibrated model can estimate them at a low cost. In this study, it was shown that with the model calibrated for farmers' conditions, not other easily measured information (such as the irrigation water volume) can be obtained, with the assumption that the model accurately captures this information as well as performance. To evaluate the simulated real performance model, it was compared with the actual performance of farmers (Agricultural Jihad Report) after calibration. In addition to phenology, the SSM model simulates traits related to growth and yield, evapotranspiration values, irrigation water volume, runoff, available soil water during planting and harvesting, cumulative drainage, etc. The output of the model shows the amount of irrigation water is needed for a certain amount of performance in a given place (with specified rainfall and transpiration). The irrigation water volume calculated by the model was compared with the results of field tests from previous studies conducted by researchers at agricultural research centers. It was found that the model's output and the observed values were in good agreement. The root mean square error for rice and wheat was 216.6 and 157.6 kg per hectare, respectively, and the coefficient of variation and correlation coefficient were 4 and 85% for rice and 3 and 94% for wheat, respectively. Then, the irrigation water volume estimated by the model was evaluated and validated with the measured irrigation water volume in different crops (in Golestan province for different years). Based on the results of the evaluation, the coefficient of variation and the correlation coefficient for the simulated irrigation water volume were 8.9 and 98%, respectively, compared with the observed value. This calibration was done for rice (paddy) and irrigated wheat in the fields of Gorgan town, and the simulation and running were done using the meteorological statistics recorded in Hashem Abad weather station, Gorgan. Noting the fact that the actual yield has been simulated with good accuracy after the calibration, it was assumed that the other estimates of the model are also reliable. Thus, the calibrated model estimates them with low cost and appropriate accuracy and can complement field experiments. ConclusionThis study discovered that the SSM_iCrop2 model, when calibrated for the conditions of farmers' fields, can accurately simulate both growth and yield traits as well as water balance characteristics. Notably, the model provides reliable estimates of irrigation water volume in farming scenarios, a crucial factor for agricultural planning and drought adaptation.
Irrigation
M. Behdarnejad; H. Piri; M. Delbari
Abstract
Introduction
In sustainable farming systems, the use of organic fertilizers is of particular importance in increasing crop production and maintaining sustainable soil fertility. Nowadays, the consumption of organic foods is introduced to consumers as an alternative. The result of the application of ...
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Introduction
In sustainable farming systems, the use of organic fertilizers is of particular importance in increasing crop production and maintaining sustainable soil fertility. Nowadays, the consumption of organic foods is introduced to consumers as an alternative. The result of the application of chemical products is the crisis of environmental pollution, soil and water resources, and the health risk to human society. Nowadays, in order to reduce the effects of misuse of chemical inputs, chemical fertilizers can be replaced with organic biological fertilizers, including animal manure, compost, and green manure. In this regard, chicken manure has a positive effect on the physical, chemical, and biological characteristics of the soil, and due to its richness in uric acid, the nitrogen contained in it is used by the plant much faster than the nitrogen of other organic fertilizers. Vermicompost is considered a good source of soil fertility due to its organic materials. Organic matter in the soil improves the permeability and drainage of the soil and also prevents excessive dryness of the soil by maintaining sufficient moisture. Despite the fact that vermicompost can be used as a fertilizer in organic farming, high levels of this fertilizer may cause salinity effects in the plant, which affects the growth and development of the plant and even it can cause the death of cucumber as one of the crops sensitive to soil and water salinity. The cucumber (Cucumis sativus L.) is one of the important vegetables that can be produced in a greenhouse all year round. Fresh consumption of cucumber throughout the year has increased its production. The development of technology and the short growth period of this product has made it possible to grow it in most climate zones. Therefore, in this research, the effects of different levels of water deficit with the simultaneous application of vermicompost and chicken manure on cucumber plants in the Behbahan region have been investigated.
Materials and Methods
In this study, different levels of irrigation water, vermicompost, and poultry manure on ground cucumber were investigated. The experiment was performed in the form of split plots based on completely randomized design and the form of stacks. Treatments included three levels of poultry manure (2, 4 and 8 ton ha-1), three levels of vermicompost (3, 6 and 9 ton ha-1) and three levels of water stress (100, 75 and 50% of plant water requirement). Both vermicompost and poultry manure were applied to the soil before planting. Harvest was done every three days. Fruit weight, diameter and length, plant length, the protein of the dry matter of the fruit percentage, and leaf chlorophyll in each plot were carefully measured. Also, the yield and water productivity at the end of the season were calculated.
Water productivity
Referring to the yield to irrigation water ratio, is obtained by the following relation (Payero et al., 2009):
WP=Y/IR (1)
In this equation, WP represents water productivity (kg/m3), Y denotes the yield (kg/ha), and IR shows the amount of irrigation water (m3/ha).
Statistical analysis
The analysis of variance for the results obtained from different treatments was conducted using SAS software (SAS 9.1, SAS Institute, Cary, NC, USA). The mean values of the main factors and interactive effects were compared using the Duncan method at the 1% and 5% levels of significance.
Results and Discussion
The results showed that irrigation, poultry manure and vermicompost had a significant effect on the measured parameters at the level of one and five percent probability. Reduction of water consumption reduced yield and yield components, but in this regard, no significant difference was observed between 100% and 75% of water requirement. The highest yield was obtained in the treatment of 100% of plant water requirement and consumption of 4 ton ha-1 of poultry manure and 6 ton ha-1 of vermicompost, in this regard, no significant difference was observed with the treatment of 75% of water requirement. According to the results obtained from this study, it can be said that there is no significant difference in terms of yield between treatments of 75 and 100% of plant water requirement. Therefore, the amount of water given to the plant can be reduced to 75% of the plant water requirement, and with proper management, less water can be consumed without a significant reduction in crop yield. Examining the effects of irrigation water on the amount of the protein of the dry matter of the fruit showed that the highest amount of the protein of the dry matter of the fruit (56.31%) was obtained in the treatment of 75% of the water requirement and the protein of the dry matter of the fruit was less in other treatments. The interaction effect of vermicompost and poultry manure resulted in the highest percentage of cucumber protein at a treatment of 4 tons ha-1 of poultry manure and 6 tons ha-1 of vermicompost (58.42%). However, when the simultaneous use of 8 tons ha-1 of poultry manure and different levels of vermicompost was employed, the percentage of protein in the fruit's dry matter decreased. The combination of drought stress, poultry manure, and vermicompost, along with their interaction effects, significantly influenced the chlorophyll a and b values at both the 1% and 5% probability levels. As the depth of irrigation water decreased, the amounts of chlorophyll a and b also decreased. The treatment with 100% water requirement of the plant showed the highest amounts of chlorophyll a (0.63 mg/g fresh weight) and chlorophyll b (0.36 mg/g fresh weight). However, no significant difference was observed compared to the 75% treatment. Regarding the interactions between vermicompost and poultry manure, it was found that when using 6 tons ha-1 of vermicompost to reduce yield and its components, the use of poultry manure should be reduced to 4 tons ha-1. On the other hand, when higher levels of vermicompost (9 tons ha-1) are used, the application of poultry manure should be reduced to 2 tons ha-1.
Result
According to the results obtained from this research, it can be said that there is no significant difference in performance between the treatments of providing 75% and 100% of the water requirement of the plant, therefore, the amount of water given to the plant can be reduced to the amount of 75% of the water requirement of the plant. With proper management, less water can be consumed without significantly reducing the yield of the product.
Irrigation
E. Farrokhi; M. Nassiri Mahallati; A. Koocheki; alireza beheshti
Abstract
Introduction: Predicting yield is increasingly important to optimize irrigation under limited available water to enhance sustainable production. Calibrated crop simulation models therefore increasingly are being used an alternative means for rapid assessment of water-limited crop yield over a wide range ...
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Introduction: Predicting yield is increasingly important to optimize irrigation under limited available water to enhance sustainable production. Calibrated crop simulation models therefore increasingly are being used an alternative means for rapid assessment of water-limited crop yield over a wide range of environmental and management conditions. AquaCrop is a multi-crop model that simulates the water-limited yield of herbaceous crop types under different biophysical and management conditions. It requires a relatively small number of explicit and mostly-intuitive parameters to be defined compared to other crop models, and has been validated and applied successfully for multiple crop types across a wide range of environmental and agronomic setting. This study was conducted as a two-year field experiment with the aim of the simulation of water productivity, above ground biomass and fresh and dry yield of tomato using AquaCrop model under different irrigation regimes applied at two growth stages in Mashhad climate conditions.Materials and Methods: A two-year field experiment was conducted during 2016-2017 growing seasons in the experimental field of Ferdowsi University of Mashhad located in Khorasan Razavi province, North East of Iran. The water-driven AquaCrop model developed by FAO was calibrated and validated to simulate water productivity, above-ground biomass and yield of tomato crop under varying irrigation regimes. AquaCrop was calibrated and validated for tomato under full (100% of water requirements) and deficit (75 and 50% of water requirements) irrigation regimes at vegetative (100V, 75V, and 50V) and reproductive stages (100R, 75R, and 50R). Model performance was evaluated in terms of the normalized root mean squared error (NRSME), the Nash–Sutcliffe model efficiency coefficient (EF), Willmott’s index of agreement (d) and coefficient of determination (R2). The drip irrigation method was used for irrigation. The tomato water requirement was calculated using CROPWAT 8.0 software. The irrigation water was supplied based on total gross irrigation and obtained irrigation schedule of CROPWAT. The 2016 and 2017 measured data sets were used for calibration and validation of AquaCrop model, respectively.Results and Discussion: Calibration results showed good agreement between simulated and observed data for water productivity in all treatments with high R2 value (0.93), good ME (0.23), low estimation errors (RMSE=0.09 kgm3) and high d value (0.85). The goodness of fit results showed that measured WP values were closer to simulated WP values for the validation season (2017) than for the calibration season (2016). During calibration, (2016), the model simulated the biomass with good accuracy. The simulated above ground biomass values were close to the observed values during calibration (2016) for all treatments with R2 ranging from 0.92 to 0.99, NRMSE in range of 7.4 to 23%, d varying from 0.94 to 1, and ME ranging from 0.71 to 0.98. Validation results indicated good performance of model in simulating above ground biomass for most of the treatments (0.92 < R2 < 0.98, 6.5% < NRMSE < 21.3%, 0.76 < ME < 0.99). During validation (2017 growing season), overall, the trend of biomass growth (or accumulation) was captured well by model. However, the range of biomass of simulation errors was high, especially in treatments with higher stress. Accurate simulation of the response of yield to water is important for agricultural production, especially in an arid region where agriculture depends closely heavily on irrigation. During validation, the model predicted dry and fresh yield satisfactorily (NRMSE = 15.64% and 11.80% for dry and fresh yield, respectively).Conclusion: In general, the AquaCrop model was able to simulate the observed water productivity, above ground biomass and yield of tomato satisfactorily in both calibration and validation stage. However, the model performance was more accurate in non- and/or moderate stress conditions than in sever water-stress environments. In conclusion, the AquaCrop model could be calibrated to simulate growth and yield of tomato under temperate condition, reasonably well, and become a very useful tool to support decision on when and how much irrigate. This study provides the first estimate of the soil and plant parameter values of AquaCrop for simulation of tomato growth in Iran. Model parameterization is site specific, and thus the applicability of key calibrated parameters must be tested under different climate, soil, variety, irrigation methods, and field management.
Irrigation
M. Emadi; M. Noshadi; A.A. Ghaemi
Abstract
Introduction: According to expantion of urbanization, it is necessary to create green space as the most important environmental factor in moderate cities. However in recent decades, shortage of water resources is one of the problems facing the expansion of green space especially grass type. Therefore, ...
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Introduction: According to expantion of urbanization, it is necessary to create green space as the most important environmental factor in moderate cities. However in recent decades, shortage of water resources is one of the problems facing the expansion of green space especially grass type. Therefore, the application of management methods such as deficit irrigation is very important. Development of green space requires sufficient water supply and according to the climatic conditions of our country, finding alternative methods and resources for effective irrigation and utilizing all available capacities is one of the main goals of municipalities and water organizations.
Materials and Methods: This research was performed in a greenhouse with an area of 120 square meters located in the college of Agriculture of Shiraz university with longitude 52032’, latitude 29036’,1810 height above sea level, and in flower pots with dimensions of 30 * 30*30 in order to investigate the effect of water stress in the traditional irrigation method on morpho-physiological factors and water productivity in two variety long grass. The research was in the form of split plots based on a random full canton with three replication and three levels (%100 per) (w1), (%75 per) (w2), (%50 per)(w3) of water requirement. The grass used in this design is Festuca, arundinacea Schreb with two variety named Asterix and Talladega which are considered as cold grasses and has a root depth of 15-20 cm. The first 3 cm of sand (to create drain conditions) was placed in the bottom of the flower pot, and then 24 cm of soil was poured on it and compacted until it reached the required density. On April 10, two variety of grass seeds were poured manually on the pots (10 grams of seeds per pot). Then, 100 gr of rotten and screened animal dung was poured on the seeds in each flower pot and irrigated with a hose by a traditional (manual) system. Early cultivation was done manually due to the application of more water and the establishment of grass. In this way, every day for a week, two to three times irrigation and after the seeds germinate (10 days after cultivation), once-daily irrigation and until the seeds germinate completely (20 days after cultivation), the irrigation period was once between 7 until 15 days, and then water stress was imposed. The first grass mowing was done after the grass was completely established (30 days after cultivation). Also, in order to compensate for the shortage of nutrients in the soil after two months (July) 6 gr /m2 of urea fertilizer (0.54 gr/ m2 to each flower pot) was applied. The onset of stress was two months after cultivation (July 10), and the duration of stress was 45 days. To determine the water requirement a separate flowerpot among the other flowerpots was located, and provide the moisture to FC level. Every other day, the water lost by this flower pot compared to the initial weight (FC), the same amount of water was given to the flowerpots with 20% more as for the leaching requirement.
Results and Discussion: Analysis of experimental data was performed by SAS 9.4 statistical software, and Duncan’s multiple range experiments at 5% level were used to compare the means, at the level of 5% probability. Results and data analysis was investigated under water stress in two varieties.
Dryness stress and water use efficiency: Water productivity in both varieties of grass and in different irrigation treatments did not change significantly at 95%. So decline in the amount of irrigation water has not affected water productivity.
Interaction of dryness and grass quality: The results showed that water stress and the interaction of water stress and grass variety on the appearance quality of grass were not significantly different at 95% and in the second ten days of August, the appearance quality was more desirable than in the first half.
Interaction of dryness and relative leaf water content of leaf: The relative water content of the leaf was weekly measured during the stress period. The results of comparing the mean relative water content (RWC) of leaf under water stress in two types of Festuca grass showed that the effect of water stress interaction was significant in Asterix grass variety on the relative water content of leaf at 95% level. The relative water content of the leaves is a good index of the water situation of the leaves, and its reduction in the leaves causes wilting and reduces the freshness and appearance quality of the grass and reducing the relative water content of the leaf has not affected the appearance quality of the grass.
Interaction of dryness and leaf growth rate: The leaf growth rate was measured during the stress period (monthly) in three ten-day periods (August). The results of comparing the means showed that the effect of water stress interaction and two variety of grasses on leaf growth rate was not significant during the first ten days. In the second ten days, the effect of water stress was significant in both Asterix and Talladega grass and growth rate in irrigation treatments of 75 and 50% (percentage) of full irrigation was significantly different from full irrigation.
Conclusion: The results of this study showed that deficit irrigation could increase water use efficiency without reducing the quality of green cover. With less water consumption (half full irrigation), the appearance quality of the grass will be well maintained. The relative water content of the leaf decreased as dryness stress progresses and causing changes in the cell membrane and thus increasing electrolyte permeation from the cell. Considering that dryness stress has not reduced the appearance quality of the grass, reducing the relative water content of the leaf has not affected the appearance quality of the grass. Generally, the growth rate in all three decades was maximum in dryness stress 75% (percentage), which indicates the high photosynthesis of the plant in this stress.
rasoul asadi; farzad hasanpour; mitra mehrabani; Amin Baghizadeh; Fateme karandish
Abstract
Introduction: In arid and semi-arid areas, water can be a limiting factor for plant growth and agricultural yields. Considering limited water resources in arid and semi-arid climate of Iran, deficit irrigation is one of the strategies for efficient use of water and increasing water use efficiency ...
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Introduction: In arid and semi-arid areas, water can be a limiting factor for plant growth and agricultural yields. Considering limited water resources in arid and semi-arid climate of Iran, deficit irrigation is one of the strategies for efficient use of water and increasing water use efficiency in agricultural lands. Deficit irrigation (DI) is a suitable solution to gain acceptable and economic performance by using minimum amount of water. The Partial Root- zone Drying (PRD) irrigation is a new improvement in deficit irrigation in which the half of the root zone is irrigated alternatively in scheduled irrigation events. The plants with PRD irrigation method can, therefore, have different root system in comparison with other irrigation methods. At this method the plant’s condition would be OK by withdrawing water from wet side, and the roots at the dry side can release abscisic acid hormone which decrease the stomatal conductance and consequently the water use efficiency would increase. Also, by using proper irrigation management in farm, we are able to utilize water, soil and fertilizer to produce high yield and quality products. Drip irrigation is considered one of the most efficient irrigation methods. One of the major advantages is its ability to apply water to the soil as often as desired and in smaller quantity than the other irrigation methods. Drip irrigation has been practiced for many years for its effectiveness in reducing soil surface evaporation and it has been widely used in horticultural crops in both greenhouse and open field.
Materials and Methods: In order to compare two deficit irrigation methods on plant growth characteristics of Rosmarinus officinalis L., a field experiment was carried out during 2016 growing season at an experimental farm in Kerman Municipality seedling production station. The experimental treatments were arranged as randomized complete block design with three replications. The irrigation regimes consisted of full irrigation (FI-100), regulated deficit (RDI75 and RDI55) and partial root zone drying irrigation (PRD75 and PRD55). In this study, drip lines were placed on the soil surface at a distance of 15 cm from the plant and plant rows were placed between drip lines. The irrigation interval was 4 days for all treatments. In the full irrigation and regulated deficit irrigation treatments, the plants were irrigated from two sides for every irrigation. In the PRD, one of two neighboring drip line was alternatively used for irrigation. The irrigation interval was 4 days for all treatments. Dry weight, leaf area index (LAI), number of shoots, plant height, water productivity, root fresh weight, root depth and root volume were measured. Since the highest essential oil of rosemary is at 50 percent of flowering time, the above-mentioned indices were measured at the middle of flowering (190 days after planting) by removing the side rows in each replicate and half a meter from the beginning and end of each row. As a marginal effect, 10 plants were randomly selected and sampled from two middle rows, each replicate of each treatment. The harvested bushes were dried at 25 °C for three weeks and then the dried weight of the vegetative organs was measured. Moreover, the number of 10 plants selected from each treatment was accurately counted to determine the number of shoots. Data were analyzed statistically using SAS Statistical software. Treatment means were compared using LSD test.
Results and Discussion: The results showed that highest herbage dry weight (145.3 g) and leaf area index in different stages of growth were under full irrigation treatment in which no significant difference between this treatment and 75 percent water replacement in partial root zone drying was observed. The highest number of shoots (128.7) and plant height (68.4 cm) were also obtained by full irrigation treatment and there was significant difference between this treatment and other treatments. However, the highest water productivity (2.06 kg/m3), root fresh weight (3.8 g), root depth (16.4 cm) and root volume (2.4 cm3) were found in 75 percent water replacement in partial root zone drying.
Conclusion: According to the results, 75 percent water replacement in partial root zone drying irrigation treatments, in addition to saving water consumption, provides better use of soil moisture and sunlight. Thus, this treatment can be considered as a suitable approach to cope with the water crisis and achieve a sustainable agriculture.
Keywords: Drip irrigation, Drought stress, Leaf area index, Medicinal plant, Rosmarinus officinalis, Water productivity
A. Sheini-Dashtgol; Saeid Boroomand Nasab; AbdAli Naseri
Abstract
Introduction: Sugarcane fields of the southwest of Iran have heavy soil texture, high temperatures, hot and dry wind flow at spring and summer seasons. The electrical conductivity of irrigation water was considered about 1.1 dS.m-1, in basic designs of this irrigation method. In addition to sugarcane ...
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Introduction: Sugarcane fields of the southwest of Iran have heavy soil texture, high temperatures, hot and dry wind flow at spring and summer seasons. The electrical conductivity of irrigation water was considered about 1.1 dS.m-1, in basic designs of this irrigation method. In addition to sugarcane production, sugar is a fundamental good in the economic section of Iran. It has multiple use in food, medical and chemical industry, production of by-products such as feedstuffs, yeast and alcohol, wood and paper. Sugarcane requires lots of water during the growing period and sensitive to water stress and is not compatible with long duration of flooding. If groundwater rises and covers the root zone, crop yield decreases due to root rot. Significant benefits are identified in terms of increased yield, improved crop quality, reduction in applied water, and reduced agronomic costs for weed control, fertilization, and tillage. Improved water management is crucial for a sustainable future, and SDI will be one tool that is available to improve water productivity. The main advantages of SDI are related to water savings because water is applied directly to the crop’s root zone, which prevents losses due to direct evaporation from the soil and deep drainage, and, if properly managed, SDI allows for the maintenance of appropriate levels of soil moisture. Due to the water crisis in Iran, this study aimed to reduce the volume of consumed water and water productivity for sugarcane and sugar yield by managing water consumption using drip irrigation for the first time in the cultivation of sugarcane. Material and Methods: According to recent droughts and severe water crises in Iran, subsurface drip irrigation was implemented in sugarcane for the first time. It seems that water consumed in subsurface drip irrigation is less than other methods. Therefore, its effect was investigated by 15, 20, and 30 cm depths and 75 cm space of subsurface emitters and comparison with control, on water productivity and sugarcane yield. An experiment based on randomized complete block design was carried out at the Sugarcane Research and Training Institute of Khuzestan in the South-West of Iran. After harvesting the plant field (start Ratoon), soil samples were collected at 0-30, 30-60, and 60-90 cm depths. In order to measure the bulk density of soil, samples were collected from the undistributed samples with sampler cylinders, and the texture was determined by the hydrometer method. To assess soil moisture percentage, pressure plate was used for determining content in field capacity (FC) and permanent wilting point (PWP) (the results were 25.1% and 12.9%, respectively). Emitters were pressure controlled emitter type, anti-siphon and the pressure at the pump station was 4.3 bar, and emitters with a flow 2.2 liter-1 and the depth of emitters pipes were 15, 20, and 30 cm from the surface soil. Depending on irrigation frequencies and irrigation water acidity, acid was injected into the irrigation water to prevent clogging of the emitters. After a specified time, it was discharged from the network. Regarding the presence of algae in irrigation water, chlorine gas was used in acid filtration before irrigation in field capacity. Finally, the average quantity and quality functions and Water Productivity in subsurface drip irrigation were compared with compression irrigation. For data fitting and curves, EXCEL software was used, and SAS statistical software was used for statistical analysis. Also, to investigate the salinity distribution in drip irrigation, the mean soil samples were used during the sampling period. The figures were drawn using 8 Surfer software in two dimensions. In drawing the shapes, Craig’s introspection was used. Results and Discussion: High evaporation, air temperature, and relatively low quality of irrigation water are the most important limiting factors for sugarcane irrigation in Khuzestan. It seems that according to the research records, the irrigation of subsurface drops with proper management is successful. Therefore, for this purpose, the effect of planting depth of 15, 20, and 30 and a distance of 75 cm drops and to compare with the regular irrigation of sugarcane lands as control (control), on water productivity and sugarcane yield complete random blocks was applied. The results of the analysis of variance of quantitative traits showed significant effects of the planting depth of droplets, in terms of yield at the level of one percent and in terms of stem height traits, number of stems per hectare, and water efficiency per sugarcane and produced sugar, at the level of five percent. According to the results of qualitative traits, the effect of treatment of droplet implant depth in all traits was non-significant. At a depth of 20 cm, the highest efficiency of water production for sugarcane and sugar production were 1.6 and 0.73 kg / m3, respectively. The lowest water productivity for sugarcane and sugar produced in the control treatment was 4.2 and 0.51 kg / m3, respectively. As a result, water productivity in the treatment of selected index (planting depth of 20 cm) per sugarcane and produced sugar has resulted in an increase of more than 30% in water productivity compared to the usual irrigation of fields (control). The results of salinity distribution around the droplets also showed that under the conditions of irrigation of subsurface droplets with salt water, the lowest salinity values were always seen as a range around the droplets. With increasing distance from the droplets, the salinity increased. More salts The drops are concentrated in the streams on both sides of the drops, The highest salinity occurred at the bottom of the furrow, and the lowest salinity was found on the ridge, where the drip pipe was planted and on either side of which there were two rows of reeds. Conclusion: Subsurface drip irrigation is one of the most optimal irrigation methods that are almost unknown to sugarcane in the executive, research, and academic sectors, and has been implemented for the first time in sugarcane cultivation in Iran. Given the recent droughts and the crisis and water scarcity, and the importance of environmental issues, it will be invaluable to investigate further and apply them. In general, in this study, using a flow rate of 2.2 lit/hr and a space of 75 cm and an installation depth of 20 cm droplets, the highest quantitative and qualitative functions and the highest water productivity per sugar cane. And the sugar produced. Also, regardless of any deepening treatment, the drip irrigation system, compared to the conventional irrigation system, reduced water consumption by about 20% and water yield by 26% per sugarcane and sugar produced. According to the results and considering the uniformity of moisture distribution, soil surface salinity, lack of runoff, protection of the discharge pipe, removal of surface evaporation and sugarcane root development, depth of 20 cm, application of the discharge pipe with a distance of 75 cm drops on the hose with a flow rate of 2.2 lit/hr are recommended. Also, although the distribution of moisture onions is provided up to a distance of 80 cm, a shorter distance between the droplets, such as 60 cm with the above flow, needs further investigation.
bijan haghighati; saeed Broomand Nasab; AbdAli Naseri
Abstract
Introduction: Potato is one of the main products of agriculture in feeding the world's population and agricultural economy. The production of potato in the world occupies the forth place after wheat, rice and corn. In Iran, annual production of more than 5.5 million tons potato, has made this crop the ...
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Introduction: Potato is one of the main products of agriculture in feeding the world's population and agricultural economy. The production of potato in the world occupies the forth place after wheat, rice and corn. In Iran, annual production of more than 5.5 million tons potato, has made this crop the most important food after wheat. On the other hand, in arid and semi-arid regions, water is the most important limiting factor for production of agricultural crops such as potato. Considering the water use efficiency is one of the most effective ways to deal with the water crisis and increasing the quality and quantity of agricultural productions. Production increasing per unit of water consumed (increasing water productivity) by improving the selection of plant varieties, irrigation management and use of new irrigation methods may be feasible.
Material and Methods: The research was performed in the Chahartakhteh research station (32° 18' N. and 50° 55' E.) with 2090 m height above sea level and semi-humid climate with moderate summers and cold winters. Average annual rainfall is about 320 mm mostly during winter. The soil moisture and temperature regimes are Typic Xeric and Mesic, respectively. Soil texture is silty clay.
In order to determine the best method of deficit irrigation for optimizing water use efficiency and yield of two potato cultivars, an experiment was performed in Agricultural and Natural Resources Research Center of Chaharmahal va Bakhtiari farm in 2013. The experiment was based on randomized completely blocks with split - split plot design in three replications. The furrow and tape drip irrigation methods were as the main plots, two potato cultivars as sub plot units and four deficit irrigation managements as the secondary sub plot units including CI(100%), RDI80(80%), RDI65(65%) of available water depletion (AWD) and partial root-zone drying (PRD) during full growth period.
Almera and Burren cultivars are two new cultivars of high yield and quality of early growth period of approximately 90-80 days, high compatibility with Chaharmahal va Bakhtiari climate and more regions of Iran.
Results and Discussion: Analysis of variance (ANOVA) of studied factors showed that the deficit irrigation management on tuber yield (ton/ha), tuber yield per plant, the amount of starch, soluble sugar, proline, chlorophyll, water use efficiency, and water productivity were significant (P≤0.01). Effects of cultivar on tuber total yield, tuber yield per plant, soluble sugar, water use efficiency, and water productivity were significant (P≤0.01). The interaction between cultivar and deficit irrigation management was only significant (P≤0.05) on tuber yield (ton/ha), proline, water use efficiency and water productivity.
The results showed that Burren cultivar in comparison with Almera was better in tuber yield (19%), water productivity (20%), water use efficiency (19%), and resistance of draught in all deficit irrigation treatments. Maximum tuber yield (59.02 ton/ha) was obtained in Burren cultivar under complete irrigation. Minimum tuber yield (23.1 ton/ha) was obtained in Almera cultivar under deficit irrigation management RDI65 (65% of available water depletion). The maximum water use efficiency (16.79 Kg/m3) and water productivity (14.78 Kg/m3) were obtained under tape irrigation and partial root-zone drying (PRD) treatment. The minimum water use efficiency (7.46 Kg/m3) and water productivity (4.81 Kg/m3) were obtained under furrow irrigation and deficit irrigation management RDI65.
Effect of cultivar was not significant on amount of irrigation water during the growing season. The amount of irrigation water for two cultivars was the same and 4711 m3.ha-1. The amount of irrigation water in the different deficit irrigation managements showed that the highest water use was in CI (5615 m3 ha-1) and lowest water use was in deficit irrigation management RDI65 (4065 m3 ha-1) treatments.
Deficit irrigation management RDI80 ،PRD and RDI65 in comparison with CI led to reduction of irrigation water amount 16, 21 and 28% of irrigation water amount.
Conclusion: Due to the results of this study, the high consumption of water in agriculture, for optimal use of available water resources, the methods with high water use efficiency and productivity, such as tape irrigation, the PRD irrigation management and the use of drought resistant cultivars is recommended. According to the limitation of water resources, for optimizing water use, the best suggestion for reducing water use on potato, is using Burren cultivar with suitable quality and high yield potential, and deficit irrigation management (PRD).
Ali Reza Tavakoli; H. Asadi
Abstract
Introduction: Two of the main challenges in developing countries are food production and trying to get a high income for good nutrition and reduction of poverty. Cereals and legumes are the most important crops in the rainfed areas of the country occupying the majority of dry land areas. Irrigated production ...
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Introduction: Two of the main challenges in developing countries are food production and trying to get a high income for good nutrition and reduction of poverty. Cereals and legumes are the most important crops in the rainfed areas of the country occupying the majority of dry land areas. Irrigated production systems had a main role in food production in the past years; but unfortunately, in recent years, with high population and competition of industry and environment with agricultural sectors, getting adequate irrigation water is difficult. The main purpose of this study is to determine the best option of crop agronomic management. Rainfed agriculture is important in the world; because this production system establishes %80 of the agriculture area and prepares %70 of the food in the world. In the Lorestan province, production area for rainfed barley is 120,000 ha and the amount produced is 120000 ton (approximately 1009 kg per ha). The purposes of this study were to evaluate cost, benefit and profit of rainfed barley production, economical and non-economical substitution of treatments in different agronomic management, study of sale return, cost ratio, determining break-even of price and comparing it with the guaranteed price of barley and estimating the value of water irrigation.
Materials and Methods: This research was carried out by sample farmers (12 farmers) on rainfed barley at the Honam selected site in the Lorestan province during 2005-07. At on-farm areas of the upper Karkheh River Basin (KRB) three irrigation levels were analyzed (rainfed, single irrigation at planting time and single irrigation at spring time) under two agronomic managements (advanced management (AM) and traditional management (TM). Data was analyzed by Partial Budgeting (PB) technique, Marginal Benefit-Cost Ratio (MBCR), and economical and non-economical test. For estimation of net benefit the following formula was used:
(1)
Where:
N.B: Net income (Rials/ ha) , B(w) : Gross income, C (w) : Cost of production,
YG: Crop yield (kg/ ha), PG : Price of crop(Rials/kg), YS: straw yield (kg/ ha PS : Price of straw (Rials/kg), C1: Total fixed cost without cost of water and irrigation (Rials/ ha), Pw: Price of water and irrigation (Rials/ m3) and W: Amount of water and irrigation (m3/ ha).
Changes of incomes and changes of costs for every treatment in different crop managements were used as follows:
(2)
(3)
Where j and j+1 show existence and substitution crop managements.
In order to determine the price of irrigation water, total cost including pump and electromotor, semi deep well, power instrument, maps, pipe transport and implementation network, other primary cost and operation cost were used. The analysis period for the instruments (pump and electromotor, maps, implementation network) was 20 years and for the semi deep well was 30 years. In this study, total cost was referred to the present value with %15 discount rate by uniform series formulas. Then, the water was used in the farm. The price of water was determined. Capital recovery formula is as follows:
(4)
Where:
A: Annual value of primary investment costs, P: Primary investment costs for irrigation system, i: Discount rate and n: analysis period.
Results and Discussion: According to the results, the price of water and irrigation at the research region based on its components and under 15% and 25% interest rates were obtained to be 213 and 338.1 Rials per cubic meters, respectively. The barley grain yield and its net benefit under advanced management were more than that obtained under traditional management.
In traditional management, the mean barley grain yield for treatments including rainfed, Single irrigation (SI) - planting and SI spring were estimated to be 1572, 2487 and 2670 kgha-1, respectively. The mean profit for rainfed barley production for treatments including rainfed, SI-planting and SI spring were estimated to be 1270.2, 2314.2 and 2607 (Thousand Rial.ha-1), respectively. In advanced management, the mean barley grain yield for treatments including rainfed, Single irrigation (SI) -planting and SI spring were estimated to be 2270, 3444 and 2853 kgha-1, respectively. The mean profit for rainfed barley production for treatments including rainfed, SI-planting and SI spring were estimated to be 1987, 3465.4 and 2519.8 (Thousand Rial.ha-1), respectively. In the research site, the mean net benefit of rainfed barley under sowing and spring single irrigation and AM, increased by about 173% and 98.4%, respectively.
Conclusion: The results showed that the substitution of AM-SI planting treatment instead of other treatments was non-economical. On the other hand, in this substitution, decreasing of profit is more than decreasing of cost. Finally, at Honam site, recommended management include: AM + planting SI, AM + spring SI, and rainfed AM, respectively.
M. Moayeri; E. Pazira; H. Siadat; F. Abbasi; hossein dehghani
Abstract
This study was conducted to assess yield, water consumption, and water productivity of maize and the factors affecting it under farmers’ management conditions at the Karkheh River Basin, Iran, during 2006 and 2007 growing seasons. The studied farms were in Evan Plain that is located in the northern ...
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This study was conducted to assess yield, water consumption, and water productivity of maize and the factors affecting it under farmers’ management conditions at the Karkheh River Basin, Iran, during 2006 and 2007 growing seasons. The studied farms were in Evan Plain that is located in the northern part of the lands downstream of the Karkheh River Dam, where summer maize is planted in 75 cm spaced rows and irrigated by furrows. During the two years of the research and considering the prevailing diversity of the sources of irrigation water (Based on the ratio), seven irrigated field units were selected as follows: two units using groundwater (wells), three units receiving surface water from irrigation network, one unit taking water directly from the river, and one unit using network and well water. In each irrigation unit, three farms were chosen with regard to irrigation and farming management. In the field trials, some physical and chemical properties of the soil, soil test for nutrition (NPK) availability, the volume of inflow applied to the field by the farmer and runoff water in each irrigation, and total crop yield was measured and maize evapotranspiration was calculated. Then, the irrigation and rain water productivity (WPI+R), water application efficiency (WAE), and maize crop water productivity (CWP) was determined for each field. Based on the two years results, the average yield of maize kernel, WPI+R , WAE, and CWP values were, 4844 kg/ha, 0.38 kg/m3, 38.6,%, and 1.01 kg/m3, respectively. The results and observations made during this study indicated that the most important reasons for low water productivity were inadequate knowledge of farmers in irrigation, plant nutrient deficiencies, and improper crop management practices.
A. Shahnazari; Mirkhaleg Ziatabar Ahmadi; ghassem aghajani mazandarani
Abstract
Rice is the most important agricultural product in the world after wheat, and Iran has a special place in producing almost two million tones of rice per year. Considering the drought crisis and high consumption of water in paddy fields, it is useful to present strategies in order to increase irrigation ...
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Rice is the most important agricultural product in the world after wheat, and Iran has a special place in producing almost two million tones of rice per year. Considering the drought crisis and high consumption of water in paddy fields, it is useful to present strategies in order to increase irrigation efficiencies. In this respect, many paddy fields in Northern Province of Iran are Land Leveled. The effect of these fields on the Water Balance Parameters, water use efficiency and water productivity has been used in this study. This research has been carried out in Qaemshahr City, Mazandaran Province, comparing two traditional and leveled paddy fields measuring 1.9 and 5.67 hectares, respectively for early-ripening local Tarom species. The water discharge rates of input and output, with 3-inch Parshall Flumes were measured. Three lysimeters were tried in order to determine evapotranspiration and deep percolation. The results demonstrate that in traditional and leveled paddy fields, water use efficiencies turned to be 62.9 and 73%, water productivity of 0.476 and 0.575 kilogram per square meter, evapotranspiration of 468.2 and 477.5 mm, and deep percolation of 196.3 and 147.8 mm, respectively. Also, 25% reduction of deep percolation parameter was observed in land leveled condition which was due to hard pan creation and can be known as the most important factor of 10% increase in irrigation efficiency.
