جستجوی مقالات مرتبط با کلیدواژه « water productivity » در نشریات گروه « آب و خاک »

Accurate 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.

In 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.

Measurement 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.

This 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.

Crop modeling is a widely used method for simulating the crop yield under different irrigation managements. Due that, in the study, a water-driven crop model, AquaCrop, was used to simulate and determine the optimal irrigation quantity and interval in Dehkhoda Sugarcane Cultivation and Industry Group (DH) farms. The data were collected from DH farms during 2019-2021. The total area under study was 230 hectares. The evaluation results showed that the AquaCrop model had an acceptable error for simulating yield (RMSE<5.6 ton ha-1) and water productivity (RMSE<2.2 kg m-3). In addition, the results of favorable efficiency (d>0.99), excellent accuracy (NRMSE<0.1) and high determination of coefficient (R2>0.94) showed that the simulation results of AquaCrop can be trusted. For this reason, 21 irrigation scenarios were simulated using the AquaCrop model in order to obtain the most appropriate irrigation amount and interval. Based on the results, close-end furrow irrigation with interval of seven days and the amount of 33000 m3 ha-1 was determined as a suitable option in terms of yield (132 ton ha-1) and water productivity (4 kg m-3). However, this scenario is for normal water conditions and if water stress conditions are created; a maximum of nine days for irrigation interval and at least 21000 m3 ha-1 is a better option for implementation in DH farms.

The main purpose of this project was to measure the amount of saffron consumed water in farms managed by farmers in Razavi and South Khorasan provinces. 126 farms in two provinces were selected in two years (2017 & 2019). The amount of water consumed by saffron in the selected farms was measured by visiting the farms, completing the questionnaire, recording the irrigation program and measuring the water source discharge. Water requirement of saffron in different regions was calculated and compared with the amount of water consumed by farmers. Analysis of variance was used to investigate possible differences in yield, irrigation water and water productivity in saffron production. Analysis of the results showed that yield, volume of applied water and water productivity of saffron in two provinces was not significantly different. The average saffron yield, water productivity and water productivity plus effective rainfall were 8.3 kg/ha, 1.9 and 1.37 g/m3, respectively. The average irrigation water consumption was 4628 and 4594 m3/ha in the Razavi and South Khorasan provinces, respectively and the average of water consumed in two provinces was 4603 m3/ha. The range of water use changes in selected farms was high and between 1543 and 8914 m3/ha. In order to improve water productivity in saffron production in Iran, it is possible to increase yield per unit area or reduce water consumption per unit area with appropriate solutions. The average irrigation efficiency in the saffron farms of the two provinces was 55 percent.

Determining and analyzing the indicators of water management for the crops of the country plays an important role in the planning of the agricultural sector.This study was accomplished to investigate water management indicators of irrigation systems in Wheat production in the upstream region of Karkheh basin and specifically Honam plain in Lorestan province. 14 wheat farms were selected in the mentioned area and were subjected to agronomic and water monitoring during the cropping season. Wheat applied irrigation water was determined by recording the irrigation schedule and measuring the flow rates. The water requirement of wheat was estimated by Penman-Monteith method and by applying plant coefficients. The yield and water productivity for wheat farms were obtained at the maturity stage. The results of agronomic and water monitoring of selected wheat fields showed that the type of agricultural, irrigation and fertilizer management of farmers played an important role in the amount of grain produced. Irrigation applied water, yield and WP was statistically different during the growth season for the farms. The average yield, the volume of irrigation water, the productivity of the irrigation water and the productivity of the applied water of wheat in the sprinkler irrigation system were equal to 6845 kg/ ha, 2325 m3/ha, 3 and 1.52 kg/ m3, respectively, and in the surface system equal to 5000 kg/ ha, 3237 m3/ha, 1.3 and 0.94 kg/ m3, respectively. The monitoring of the irrigation program in the selected fields showed that the farmers irrigated the mentioned fields on average 41% less than the full irrigation requirement of the plant. One of the important reasons for this is the special attention of farmers in the region to plant crops with high profitability, such as alfalfa and clover, despite the need for more water than wheat.

Camelina is an oilseed plant that could produce proper yield in arid and semi-arid areas with low water consumption. To investigate camelina response (Sohail cv.) to application of different amounts of irrigation water, this study was conducted in 2022-23 in Khatam District, Yazd Province. Treatments included drip tape irrigating based on 100% (full irrigation as control), 75% and 50% of full irrigation. Results showed that the effect of irrigation treatments on biological yield, grain yield, harvest index, plant height and protein percentage of camelina was significant (p<0.05). However, by reducing the volume of irrigation water, biological yield decreased significantly, such that biological yield of 75% and 50% treatments decreased by, respectively, 18.3% and 46% compared to the control treatment. The highest grain yield (2373.3 kg ha-1) was obtained with the application of 2384 m3 ha-1 irrigation water (control). By reducing the amount of irrigation water by 75% and 50%, grain yield decreased by 31.4% and 40.0%, respectively. The harvest indices were 22.6%, 19.0% and 25.1% for 100%, 75%, and 50% treatments, respectively. The highest plant height was 90 cm for the control treatment. The water productivity ranged from 0.88 kg m-3 for 75% treatment to 1.04 kg m-3 for the full irrigation. The highest proline content was observed for the treatments of reducing the volume of irrigation water, in which the amount of proline increased by 1.4 times compared to the control treatment. The results showed that the amount of irrigation water required for camelina was lower compared to the common winter crops, especially in tape irrigation method. Therefore, this plant could be used as a low water-demanding for delayed planting in winter season.

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

The implementation of the Khuzestan Land reclamation Plan, has been provided a suitable platform to promoting research findings on the proper use of soil and water resources, agricultural inputs and increasing crop production. Therefore, this study was carried out in the agricultural year 2017-2018 with the aim of evaluating the water productivity resulting from improved management of canola production inputs and comparing it with conventional management in the northern lands of Khuzestan province. For this purpose, 11 farms (advanced management treatment) were selected to apply technical packages including irrigation scheduling, using the minimum tillage, applying balanced plant nutrition, raised bed planting, proper seed rate, according to farm conditions and farmer facilities. In each of these farms, the amount of applied water during the growing season, grain yield and water productivity were determined and compared with the surrounding farms data with traditional management (control treatment). The results showed that the average canola grain yield and water productivity increased from 2413 kg ha-1 and 0.51 kg m-3 in the control treatment to 2994 kg ha-1 and 0.69 kg m-3 in the superior treatment, respectively. This increase was statistically significant at the level of 1%.

The water productivity index (WP), which is defined as the crop produced per unit of consumed water, has been considered as a key indicator for the optimal use of water in the agricultural sector. It has been heavily relied upon in the Iran's agricultural water policies and plans. However despite several years have passed since the introduction of this concept and index, unfortunately, water crisis still exists and is expanding in the country and measures to increase WP in agricultural products have not yet been able to effectively solve the country's water issues. In this review-analytical paper, the issues and challenges of using this index in practice have been discussed and the shortcomings, challenges, measures, and infrastructure necessary for the proper use of this index have been discussed and analyzed. According to the results, there are hidden issues and challenges (in 8 groups) in its application. The most important of which are the need to deeply understand the concept and definition of WP in the country's expert and management community, and the problems and issues of using the index from the aspect of lack of the required infrastructure for the proper impacts of improving WP in mitigating water scarcity. According to the identified issues and challenges, it was concluded that improving WP could not be a sole measure to solve the country's water crisis, because it fulfills just initial conditions. In order to fulfill conditions sufficiently and to implement related comprehensive measures and interventions, the necessary hardware, software, legal, and policy infrastructures must be provided.

Water scarcity and the recent droughts have multiplied the necessity of proper and optimal use of limited water resources. Drip irrigation is one of the new methods of irrigation that is used with the aim of optimal use of water and increasing water productivity in many agricultural products including wheat. This research was conducted in order to investigate the drip irrigation systems (Tape) implemented in the wheat fields of Hamedan province and compare it with other common systems during 2016-2018. In this research, first, farms were selected and evaluated by random sampling method. The measured parameters included the amount of irrigation water, yield, water productivity, water salinity and soil salinity changes. The volume of irrigation water in fields with drip irrigation varied from 2716 to 5760 m3/ha and was determined as 4153 m3/ha on average. The average volume of irrigation water in sprinkler and surface irrigation systems was determined as 4090 and 5918 m3/ha, respectively. The highest amount of yield was determined as 5581 kg/ha in the drip irrigation. The average yield in sprinkler and surface irrigation systems was estimated to be 4381 and 3000 kg/ha, respectively. The highest average water productivity (irrigation+ effective rainfall + leaching) related to the drip irrigation system and is 0.88 kg/m3 , and it was determined as 0.8 and 0.39 kg/m3 in sprinkler and surface irrigation system, respectively. Therefore, drip irrigation has increased water productivity by 10% and 125.6% compared to sprinkler and surface irrigation systems. Also, the results of this research showed that the salinity of the soil in the drip irrigation system increased at the end of the growing season compared to the beginning of the spring season. Therefore, leaching water requirement should be added to the amount of applied water (irrigation water + effective rainfall) in the drip irrigation system.

Water and nitrogen are the most important factors affecting the quantitative and qualitative performance of medicinal plants. Since the performance of the fertilizer level depends on the appropriate amount of irrigation water, it is important to examine the water and nutritional requirements of medicinal plants in order to achieve the desired quantitative and qualitative performance and the physical and economic water productivity indexes of these plants. Celandin (Chelidonium majus L.) plant is one of the very old medicinal plants, and all its parts, especially its sap and root, were used in the treatment of skin disorders, especially leprosy, toothache, and also as a choleretic, and in recent years most of its aerial parts, which are collected during the flowering stage, are used to treat some diseases, especially cancers of the digestive system. Also, all the parts of this plant contain orange sap rich in alkaloids Chelerythrine, Chelidonine, Sangunarin, Berberine, etc., which increases the importance of the production of this plant. There are many reports about the effect of irrigation interval and nitrogen fertilizers level in relation to various agricultural, garden and medicinal plants, but there is still no comprehensive and complete information about the effect of these factors and their optimal levels for the cultivation of Celandin medicinal plants. Therefore, it is necessary to evaluate the yield and indexes of physical and economic productivity of water in Celandin medicinal plant at different levels of irrigation and nitrogen fertilizer.

In order to investigate the effect of the irrigation interval and ammonium nitrate on the yield and indexes of physical and economic water productivity of Celandin (Chelidonium majus L.) medicinal plant, an experiment was conducted as a factorial in the form of a completely randomized design in three replications in the research greenhouse of the Faculty of Agricultural Sciences of University of Guilan in 2017. The factors include irrigation interval in three levels (4, 8 and 12 days) respectively as I1, I2 and I3 and nitrogen fertilizer based on ammonium nitrate in five levels (0, 45, 60, 75 and 95 kg per hectare) as respectively was N0, N45, N60, N75 and N95. To prepare the planting bed, the top soil of the garden, dune sand, and animal manure were mixed in the ratio (1:1:1) and filled in pots with an average diameter of 20 cm and a height of 18 cm. After preparing the soil sample, some physical properties (soil moisture coefficients of FC and PWP using a pressure plate device, soil texture using the hydrometric method and dry bulk density using the core sampler method) and chemical properties of the soil (calcium, potassium, phosphorus, nitrogen, organic carbon, pH and ECe) were determined. At the end of the experiment, when the plants flowered (about 225 days after transplanting), to calculate the weight of the roots and aerial parts, the plants were removed from the pot and their roots were separated from the aerial part. After washing the roots, each one was weighed separately with a sensitive digital scale (Sartorius model) with an accuracy of 0.001 grams. Then, with regarding the amount of water consumed in each irrigation treatment, the physical and economic water productivity indexes were determined based on the wet weight of the whole plant, which includes the root and aerial parts of the plant.

The results of variance analysis of data showed that the interaction effect of irrigation interval and amount of ammonium nitrate on yield and indexes of physical and economic water productivity was significant at the 5% probability level. Thus, the highest plant fresh weight was obtained with 92.92 g/plant in an 8-day irrigation interval with a fertilizer level of 95 kg/ha, and the lowest with 45.36 g/plant in a 12-day irrigation interval with a fertilizer level of 60 kg/ha. Also, the highest indexes of physical and economic water productivity based on benefit per drop and net benefit per drop based on the fresh weight of the total plant with 8.65 kg/m3 and 3463932999 and 17319665 rials/m3 respectively in the 8-day irrigation interval treatment with fertilizer level 95 kg/ha, and the lowest of them was obtained with 2.44 kg/m3, 9774464 and 4887232 rials/m3 respectively in the 4-day irrigation interval treatment with zero fertilizer level. In addition, 50% water consumption was saved in the 8-day irrigation interval treatment compared to the 4-day irrigation interval treatment. Therefore, I2 irrigation interval treatment with N95 ammonium nitrate fertilizer level is the most suitable option in terms of yield and physical and economic water productivity indexes for the production of the medicinal plant Celandin in greenhouse conditions.

Biochar as a porous material is rich in biological carbon in a stable form. Its structure is capable to store water and nutrients. Therefore, it is used for retention of such materials, especially in sandy soils. Biochar can improve water productivity in the agricultural sector in drought stress condition to achieve food security in the world. In order to study the effect of deficit irrigation and biochar on yield of coriander in a coarse-grained soil under water stress, this research was conducted using a factorial manner and a completely randomized design in the research greenhouse of Urmia University. The experimental treatments included three levels of irrigation: 100%, 75%, and 50% of the plant water requirement, and three levels of biochar application: 0, 2.5%, and 5% of the weight of each pot, which totally included 27 treatments. Irrigation was applied on the basis of plant requirement and soil water content below field capacity and the applied water was measured during the growing season. For each pot, quantitative parameters including weights of dry and wet plant, stem, leaf, and root were accurately measured. The results showed that the effects of irrigation levels and biochar on some measured parameters were significant at the probability level of 1% and 5%. The results demonstrate that by applying deficit irrigation, the measured quantitative parameters and plant yield decreased. The highest value of the parameters was obtained from the treatment of 100% water requirement and use of biochar up to the level of 2.5% of the soil. Therefore, applying suitable amount of the biochar as soil amendment improves coriander plant's growth and yield.

In most arid and semi-arid areas, water limitations are one of the main reasons for the reduced plant growth and yield under irrigation and dry land (rainfed) conditions. The aim of this study was to compare the morphophysiological responses of rapeseed cultivars to supplementary irrigation and dryland conditions. For this purpose, an experiment was carried out as a split plot in the form of a randomized complete block design with three replications during 2017-2018 in the Gachsaran Agricultural Research Station. Irrigation treatments were at four levels (no irrigation=I0, supplementary irrigation at flowering stage=I1, supplementary irrigation at grain filling stage=I2, and supplementary irrigation at flowering stage+ grain filling=I3) in the main plot, and cultivars Hayola 401, R. J. S, and Shirali as factorial in the sub-plots. The results showed that supplementary irrigation increased plant height, number of sub-branches per plant, 1000- grain weight, grain yield, and oil percentage compared to rainfed conditions. With supplementary irrigation, the weight of 1000 grains increased by 32% compared to rainfed. Grain yield increased from 755 in rainfed conditions to 2350 kg.ha-1 with two supplementary irrigations. With two supplementary irrigations, the oil content increased by 11.8% compared to the rainfed conditions. In all irrigation treatments, grain yield and oil content of Hayola 401 were higher than R. J. S and Shirali cultivars. In general, supplementary irrigation improved morphophysiological traits, yield, and percentage of grain oil. In rainfed rapeseed cultivation, with supplemental irrigations at flowering and grain filling, water productivity increased from 0.21 to 0.53 kg m-3 grain yield from 755 to 2350 kg ha-1 and oil percentage from 35.4 to 36.9.

Rice is one of the most important agricultural products in the world. Rice cultivation in Iran has great economic and social importance. Mazandaran province is one of the most important rice production centers in Iran, accounting for 44% of the Iran's rice production. Due to the high consumption of water in the agricultural sector, the optimal use of water resources in agriculture is necessary.The water required by rice is directly related to evapotranspiration. The most reliable method of calculating evapotranspiration is using a lysimeter. The purpose of this experiment is to calculate the evapotranspiration of different varieties of rice using mini-lysimeters and to introduce the best variety for cultivation.

The experiment was conducted as randomized complete block design with three replications and eleven treatments, at Rice Research Institute of Iran (Amol) during the 2020. The treatments included different rice varieties in 11 levels T1: AR2, T2: AR6, T3: AHS, T4: DAH, T5: 1117, T6: 952, T7: 956, T8: E104, T9: S715, T10: Tarom, and T11: Shiroodi. Mini lysimeters with open bottom and closed bottom had a diameter of 60 cm and a height of 50 cm. Field soil was sampled from 0 to 30 cm depth and studied in the laboratory. The date of transplanting was similar in all rice cultivars The planting density of seedlings was 20×20 cm and 7 seedlings were placed in lysimeter. The lysimeters were placed 6 cm above the ground in the soil. The seeds were planted in a treasury and the seedlings were placed in the lysimeter after 30-35 days (after 3-4 leaves and height 25-20 cm). Water management in lysimeters was in the form of flooding (5 cm). Finally, variance analysis of the obtained data was done using SAS software and the mean of the treatments were compared through the least significant difference (LSD) test at 5% probability level.

The results showed that different varieties and lines of rice was effective on infiltration, evapotranspiration, yield, water consumption and were statistically significant at 1% level of probablity. The highest and lowest evapotranspiration with averages of 4938.7 and 3747 m3/ha belonged to T9 and T5 treatments, respectively. The highest and lowest yields with averages of 7773.7 and 2938.1 kg/ha belonged to T8 and T6 treatments, respectively. The highest and lowest values of deep percolation were observed with averages of 303.3 and 185.3 mm in T9 and T5 treatments, respectively. The highest and lowest amount of applied water with averages of 9972 and 7600.3 m3/ha belonged to T9 and T5 treatments, respectively. The highest and lowest water productivity with averages of 0.98 and 0.3 kg/m3 were related to T8 and T9 treatments, respectively. The results showed that the length of the plant growth period was different in the tested cultivars and lines and it was effective on the amount of water consumption..

Finally, in the normal conditions of the region, line E104 is introduced as the best treatment due to the production of maximum grain yield, while in water shortage conditions, the line 1117 is recommended for planting due to less water consumption.

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.

 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.

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.

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.

In this research, the effect of irrigation water salinity and salicylic acid spraying were investigated on the yield of shallot (Qazvin local variety). Water salinity treatments at four levels of 2(S1), 4(S2), 6(S3), and 8(S4) dS.m-1 and salicylic acid at four concentrations of 0(A1), 0.5(A2), 1(A3) and 2(A4) mM were applied in the greenhouse. The experiment was performed as factorial and in a completely randomized design, with three replications. Soil moisture was measured daily, and irrigation scheduling was done based on it. Results showed that salinity stress reduced crop water uptake and shallot tuber weight. Salicylic acid application improved crop water status and increased tubers weight under salinity stress. A4 treatment was the ideal concentration for maximum yield. Application of 2 mM salicylic acid at salinity levels of S1, S2, S3, and S4 increased tubers yield by 11.6%, 32%, 40% and 91%, respectively, compared to the control (A1). The response of dry yield to evapotranspiration showed that by increasing salinity stress, percentage of yield decreased more than the percentage of evapotranspiration. Use of salicylic acid decreased dry yield sensitivity to salinity stress, such that from treatment S1 to S4 yield response coefficients (Ky) were between 1.01- 1.62 (in A1 treatment), 0.93- 1.3 (A2), 0.48- 1.09 (A3) and 0.31- 0.97 (A4). The effect of salicylic acid on water productivity were calculated between 2.13- 1.14 (in A1), 2.15- 1.68 (A2), 2.26- 2 (A3), and 2.38- 2.19 kg.m-3 (A4). In conditions of using saline water for crop irrigation, application of salicylic acid will increase water productivity. Based on the experiment results and in conditions of lack of high-quality water for irrigation, salicylic acid spraying on crops will be a suitable method to reduce the harmful effects of salinity stress.

Water scarcity is the most important factor limiting the production of agricultural products, especially in arid and semi-arid regions. Application of some materials such as superabsorbent polymers in soil increases water retention in soil and thus reduces water consumption and fertilizer leaching. These materials can reduce the effects of dehydration on the plant and lead to increased yield in arid and semi-arid regions. In order to investigate the effect of superabsorbent under water stress conditions on yield, yield components and some physiological characteristics of corn, experimental plots were conducted in the form of split plots in a randomized complete block design in Gotvand region in Khuzestan province. Three treatments of Aquasorb 3005 (600,300,0 kg / ha) A1, A2 and A3 and four irrigation strategies (50,75,100,125) percent of water requirement I1, I2, I3 and I4 in three replications for two growing seasons, respectively Summer 2019 and spring planting 2020) were considered. Irrigation planning, biological yield, harvest index and canopy cover were measured at different stages of growth seasons, based on which a growth simulation model was presented using AquaCrop software. The results of this test showed that the use of Aquasorb 3005 increased product performance by one percent. In addition, the results show the effect of superabsorbent application and irrigation planning on improving water efficiency. The highest grain yield in spring and summer cultivation was related to I2A3 treatment equal to 9055 and 9255 kg / ha, respectively, and the lowest yield in both crops was related to I4A0 treatment equal to 5977 kg / ha in spring cultivation and 6344 kg / ha in summer cultivation.

Water management in the agricultural sector is very important as the largest consumer of water resources in the country. Estimation or determination of water use management indicators, including the amount of water consumed, irrigation efficiency and water productivity of various agricultural and horticultural crops in the country, is one of the most important key indicators in macro-planning related to supply of water, allocation and consumption in different sectors including agriculture. The volume of water used by agricultural crops as one of the indicators for evaluating the optimal use of water resources and plays a very important role in the management and macro-planning in the field of water management and engineering. Barley plant is cultivated and produced in almost all the countries of the world and it is considered as the fourth grain in the world in terms of production after wheat, corn and rice. In Iran, barley with a cultivated area (irrigated and rainfed) of more than 1,684,000 hectares and with a production of more than 3,176,000 tons, after wheat, it is the most important crop and is cultivated in most parts of the country due to its wide ecological compatibility. 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.

In Khorasan Razavi province, 2 cities with the highest area under barley cultivation were selected for evaluation, Sabzevar and Neyshabur. To conduct this research, 12 fields in Sabzevar region and 12 other fields in Neyshabur region have been selected. The volume of irrigation water was measured in these 24 fields during the irrigation season. The measurements were carried out in different irrigation and planting methods, various soils, different salinity of irrigation water and soil and different barley varieties during the growing season of 2021-2022 without interfering with the farmer's irrigation management. The measured values were compared with the gross irrigation water requirement estimated by the Penman-Monteith method using the last 10 years meteorological data and also with the national water document values. Crop yield was recorded at the end of the growing season and water productivity was calucated as the ratio of yield to total water (irrigation applied water and effective rainfall).

The results showed that the amount of applied water, the amount of barley yield and the water productivity in Sabzevar region were 4710 m3/ha, 2.86 ton/ha and 0.77 kg/m3, respectively. The amount of applied water, the amount of barley yield and the water productivity in Neyshabur region were determined as 4408 m3/ha, 2.54 ton/ha and 0.61 kg/m3, respectively. The volume of barley irrigation water in the studied areas varied from 2393 to 7911 and its weighted average (based on the cultivation area) was 4593 m3/ha. While the average gross requirement of irrigation water in the studied areas using the Penman-Mantis method using meteorological data of the last ten years and the national water document was 9111 and 8489 m3/ha, respectively. The average yield of barley in the selected fields varied from 1600 to 5600 and its weighted average was 2310 kg/ha. Irrigation water productivity in the selected farms varied from 0.24 to 2.34 and its weighted average was determined to be 0.58 kg/m3. The applied water productivity in the selected farms varied from 0.21 to 1.57 and its weighted average was determined as 0.45 kg/m3.

According to the results of this research, in the two regions of Sabzevar and Neyshabur, the weighted average (based on the area under barley cultivation in the two regions) of the volume of irrigation water and the irrigation water productivity in barley fields are 4593 m3/ha and 0.58 kg/m3, respectively. It was obtained. The amount of irrigation water in the production of barley in these two regions is about 5.8% less than the national average and the applied water productivity is about 35.6% less than the national average. The calculated gross irrigation requirement was obtained by using the national water document and the book "Estimation of water requirement of agricultural and horticultural plants of the country", respectively 9111.3, 8489 and 8566 m3/ha. In terms of the share of effective rainfall in irrigation water, the results showed that 37 and 27% of the amount of irrigation water was supplied through effective rainfall in Neyshabur and Sabzevar, respectively. By comparing the amount of irrigation water used by farmers in the barley fields with the gross irrigation requirement, the result was that the farmers did not have enough water for irrigation and Unintentionally, they have done deficit irrigation in the barley fields, and in fact, the farmers have done irrigation as much as they had water.

This research was conducted with the aim of investigating the effects of salinity and biochar on quinoa plant in deficit irrigation conditions. The experiment was carried out in a factorial and completely randomized design with three replications in greenhouse conditions. The treatments include three irrigation water treatments (60, 80 and 100% of the water requirement, ), three biochar treatments (0, 2 and 4% by weight of potting soil, ) and three the water quality treatment was (1, 4, and 7 dS/m, ). From the time of planting until the establishment of seedlings, all the pots were fully irrigated with fresh water and up to the agricultural capacity. Then the pots were weighed every other day and at each level of biochar and salinity, the deficit irrigation to the level of humidity was calculated based on the changes in the pot's weight. At the end of the growing season, the seeds were harvested from the spike. The index parameters of leaf area, spike weight, seed yield, water consumption efficiency and seed protein percentage were measured carefully in each pot. . With the reduction of irrigation water, the amount of quantitative parameters and plant yield decreased. The use of biochar up to the level of 2 percent by weight of the soil increased the parameters. The use of biochar at the level of 2 and 4% by weight increased the seed protein by 23.5 and % 12.08 respectively, compared to the control treatment. there was no significant difference in yield between 2 and 4 dS/m salinity treatment and the percentage of seed protein in 4 dS/m salinity was higher than 2 dS/m, it is possible to use water with 4 dS/m salinity for quinoa irrigation.

In order to investigate the effects of deficit irrigation and organic mulch on wet matter, dry matter, plant height, wet yield productivity, dry yield productivity and leaf area of corn forage (SC. 704) in Khorramabad region, an experiment based on the factorial experiment with a basic design of randomized complete blocks with three replications was conducted. The first factor of the experiment consisted of four levels of irrigation (100, 80, 60 and 40% of water requirements) and the second factor included three levels of organic mulch (no mulch (control), using 7.5 ton/hectare and 15 ton/hectare mulch). In this research, drip irrigation system (Tape) was applied and class A evaporation pan was used to determine the water requirement of the plant. The results showed that the mutual effects of deficit irrigation and organic mulch were significant at the 5% probability level. The maximum amount of wet matter (99.05 ton/ha), dry matter (31.15 ton/ha), plant height (2.38 m) and leaf area (7511cm2) were observed in the treatment of 100% water requirement and using mulch (15 ton/ha) which increased by 24.7%, 18.03%, 5.8% and 48.38% respectively compared to the control treatment. The maximum amount of water productivity for wet and dry matters were 14.56 and 4.57 kg/m3 which were obtained in the treatment of 80% water requirement and using mulch (15 ton/ha). The minimum amount of water productivity for wet and dry matters were 10.09 and 3.35 kg/m3 which were obtained in the treatment of 100% water requirement without using mulch.  Thus, in this region, irrigation based on 80% water requirement and using mulch (15 ton/ha) may cause improvement in corn forage yield.