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Saeid Habibi; Mojtaba Khoshravesh; Rassol Nouri Khajebelagh
Abstract
Water, food, and energy are three essential sources for maintaining life and fostering socio-economic development, and they are inseparably interconnected. The aim of the present study was to examine the indicators of water, energy efficiency, and global warming potential of major agricultural products, ...
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Water, food, and energy are three essential sources for maintaining life and fostering socio-economic development, and they are inseparably interconnected. The aim of the present study was to examine the indicators of water, energy efficiency, and global warming potential of major agricultural products, namely wheat and rapeseed, in two different climates in Sari and Sharifabad plains. To investigate these indicators in wheat and rapeseed crops, data from the agricultural year 1400-1401 were utilized. Initially, the sample size was determined based on the Cochran formula. Subsequently, sampling was done using a questionnaire designed by the researchers themselves. The questionnaires numbered 300, and the collected information included input consumption and production quantities. The results of water physical efficiency showed that the average water physical efficiency in Sari plain for wheat and rapeseed crops was 1.13 and 0.67 kilograms per cubic meter, respectively, while in Sharifabad plain, it was 0.83 and 0.35 kilograms per cubic meter, respectively. Furthermore, the results for energy indicators indicated that the highest level of input energy in Sari and Sharifabad plains for wheat was 80618 and 71072 megajoules per hectare, respectively. The results also showed that greenhouse gas emissions were higher in Sari than in Sharifabad, attributed to excessive fertilizer and pesticide use in Sari. The highest greenhouse gas emissions in Sari for wheat were 2495 kilograms of CO2 per hectare, and in Sharifabad, it was 2299 kilograms of CO2 per hectare. Overall, the results indicated that crop performance in humid regions is higher than in dry and semi-dry regions, and this indicator depends on various parameters, including water consumption and management discussions.
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Sara bulukazari; Hossein Babazadeh; Nyazali Ebrahimipak; Seyed Habib Mousavi-Jahromi; Hadi Ramezani_etedali
Abstract
In exploitation of low-quality water in arid and semi-arid regions, irrigation management is essential to increase water use efficiency. Determination of crop-water-salinity production function is an essential tool for proper irrigation management. In this study, the AquaCrop model was first evaluated ...
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In exploitation of low-quality water in arid and semi-arid regions, irrigation management is essential to increase water use efficiency. Determination of crop-water-salinity production function is an essential tool for proper irrigation management. In this study, the AquaCrop model was first evaluated by considering 4 soil and water salinity levels and 4 deficit irrigation levels for the major cereal crops including wheat, barley, and corn in Qazvin Plain. The results showed that the coefficients of determination for wheat, barley, and corn yield were 0.97, 0.86 and 0.91, respectively. Therefore, the model can evaluate the performance in salinity and deficit irrigation conditions with a good approximation. To determine the optimal production functions of each crop, the results of the plant model were compared with three models of linear and nonlinear regression, and artificial neural network. The neural network model was able to estimate the performance compared to the AquaCrop model with lower error and higher correlation (0.99). These values in the linear function for wheat, barley, and corn were 0.98, 0.95, and 0.78 and in the nonlinear function as 0.92, 0.86 and 0.81, respectively. Also, the error calculated in the neural network method for wheat, barley, and maize was 40.16, 62.09, and 57.08 kg, respectively, which were less than the linear model by 75 %, 70 %, and 95 %; and less than the exponential model by 90 %, 85 %, and 93%, respectively. The best trained network for determining the water-salt production function for barley and wheat 5 Nero and for corn 7 Nero was introduced in the single layer structure. Sensitivity analysis on wheat and barley showed that this model had low sensitivity to irrigation and salinity parameters and only corn plant showed a moderate range sensitivity to salinity parameter.
Khadijeh Barati; Jahangir Abedikoupaee; Elham Darvishi; Arash Azari; Ali Yousefi
Abstract
To prepare the National Water Document of the country, a 25-year statistical period of 1970-1995 has been used to calculate daily potential evapotranspiration. Due to the climate changes that have taken place in recent years, updating this national valuable work is necessary. Since so far there has been ...
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To prepare the National Water Document of the country, a 25-year statistical period of 1970-1995 has been used to calculate daily potential evapotranspiration. Due to the climate changes that have taken place in recent years, updating this national valuable work is necessary. Since so far there has been no study on determining the changes in irrigation requirement of plants of cropping pattern in Kermanshah plain in the current climate conditions compared to the values presented in NETWAT software, this subject was investigated. In this study, to calculate crops water requirement, the meteorological data of 2006-2007 to 2015-2016 were used. In order to estimate the net irrigation requirement for cropping pattern in Kermanshah plain, ET0 calculator software was used to calculate evapotranspiration of reference crop. Then, the evapotranspiration values of the cropping pattern, the effective rainfall and, eventually, the amount of net irrigation requirement of the crops were calculated. The comparison between the values obtained in this research with available values in NETWAT software indicate that, for most plants, the obtained values in this study are on average 1.2 times the amounts presented in the NETWAT software. This ratio is about 2 for wheat and barley and about 1 for clover, cantaloupe, pea, and almond. The results of lysimeteric researches in the study area confirms the correctness of the performed calculations in this study.
mohammad alavi; jahangir abedi; behrooz mostafazadeh
Abstract
Due to shortage of water, use of wastewater for irrigation is becoming more important. Also, using natural and non-toxic materials that increase fertilizer application efficiency and decrease nitrate leaching has gained increasing attention. The aims of this study were to investigate the effect of two ...
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Due to shortage of water, use of wastewater for irrigation is becoming more important. Also, using natural and non-toxic materials that increase fertilizer application efficiency and decrease nitrate leaching has gained increasing attention. The aims of this study were to investigate the effect of two sizes for particles, i.e. 1-1.68 mm and 53-63 μm, and two application rates (20 and 60 grams per kilogram of soil) of natural zeolite of clinoptilolite (Cp) and surfactant-modified zeolite (SMZ) on soil nitrate and ammonium leaching and wheat plant performance under irrigation by treated urban wastewater. The experiment was conducted in 2015-16 growing season. The experimental soils were placed in Polyethylene columns with 11 cm inner diameter and 65 cm height. The treatments were factorial combination of the variables in completely randomized design with three replications. The results showed that the total amount of released NO3-N from columns modified by SMZ and CP were 32% and 21% lower as compared to the control treatment. Also, these amendments improved wheat plant growth. There was no significant effect on nitrate leaching due to the particle size of the two soil amendments. CP and SMZ amendments are eco-friendly materials and results of the study showed that they were effective in controlling soil nitrate leaching and improving wheat plant growth.
Hosein Zahedpour; Vahid Rezaverdinejad; hossin dehghani sanich
Abstract
Improving water productivity and irrigation efficiency is important in Iran due to limitations in water quality and quantity. This study was conducted to investigate and analyze application efficiency and water productivity at field scale in Nazloo-Chay plain, located in Urmia province, during 2015-2016. ...
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Improving water productivity and irrigation efficiency is important in Iran due to limitations in water quality and quantity. This study was conducted to investigate and analyze application efficiency and water productivity at field scale in Nazloo-Chay plain, located in Urmia province, during 2015-2016. For this purpose, five wheat fields, as fall planting, and five fields for spring crops i.e. maize and pumpkin (two fields of each) and sunflower (one farm), were studied. Irrigation system in wheat fields was border, while spring crops were furrow irrigated with closed end condition. To evaluate and measure the water productivity and irrigation efficiency in each irrigation event, some parameters were measured including irrigation depth, system geometry, soil water depletion in the root zone before irrigation (SMD) and the plant parameters. In the five wheat fields, a total of 21 irrigation events were performed and all of which were monitored and evaluated. The average of irrigation efficiency and standard deviation in the 21 irrigation events at these five wheat fields was about 30.9% and 19.5 percent, respectively. For the three spring crops, 27 irrigation events were evaluated and the overall average irrigating efficiencies for sunflower, pumpkin (cucurbita) and maize were about 69.3%, 51.5% and 52.5%, respectively. The average of standard deviation in spring plantings was calculated at about 13.9 percent, which indicates that the scattering of application efficiency was less in spring plantings than fall planting. Based on the results, the average of physical water productivity in wheat fields was 1.1 kg/m3. This index for sunflower, pumpkin (Cucurbita) seed and maize was calculated at about 0.27, 0.17 and 7.02 kg/m3, respectively. Average economic water productivity in wheat was 14512.4 Rial/ m3 and for sunflower, maize and cucurbita seed were 20252.6, 13463.9, and 23305.3 Rial/ m3, respectively, which indicated high economic water productivity for sunflower and Cucurbita seed. Generally, the crop management practices in all fall and spring plantings including fertilizer and pesticides applications were based on scientific recommendations, but irrigation management was poor in all farms. One of the main reasons for low application efficiency in these farms (in particular the fall plantings) was the poor field leveling that required high water depths for irrigation of the fields.
m y; Mohsen Ahmadee; s b; a h
Abstract
Climate change has important impacts on most of the natural processes, including hydrological cycle. Evapotranspiration, as a part of hydrological cycle, will also undergo these changes. Due to the importance of evapotranspiration in water resources and agricultural management, this research was ...
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Climate change has important impacts on most of the natural processes, including hydrological cycle. Evapotranspiration, as a part of hydrological cycle, will also undergo these changes. Due to the importance of evapotranspiration in water resources and agricultural management, this research was conducted to study climate change effect on evapotranspiration in Neyshabour plain. Evapotranspiration was calculated for five farms in Neyshabour plain using SWAP software and meteorological and agronomic data. In irrigated farms, the HADCM3, ECHAM5OM and CGCM3T47models were used to calculate crop actual evapotranspiration for 2020-2039 and 2080-2099 periods based on A2, B1 and A1B scenarios and the climate model used in rainfed farms was the HADCM3 based on A2 and B1 scenarios. The greatest calculated difference in evapotranspiration was found between the period 2080-2099 and base period (1992-2011) in the A2 scenario. Also, evapotranspiration values for the period 2080-2099 will increase compared to the period 2020-2039 in all three scenarios. Among the crops of investigate, wheat will have the greatest changes (12%) in evapotranspiration in the future periods compared to the base period, while changes of maize will be only 3%. However, the average daily evapotranspiration of maize during the growing season (about 12 mm/day) will be more than the other crops.
Farhad Rejali
Abstract
One of the beneficial effects of mycorrhizal symbiosis is declining the deleterious effects of environmental stresses in plants. Drought stress is one of the most important environmental stresses which is the results of our country climate. In this situation decline of mineral uptake especially phosphorus ...
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One of the beneficial effects of mycorrhizal symbiosis is declining the deleterious effects of environmental stresses in plants. Drought stress is one of the most important environmental stresses which is the results of our country climate. In this situation decline of mineral uptake especially phosphorus and zinc have more negative effects than lack of water in plant growth. Mycorrhizal fungi by increasing the mineral uptake can alleviate the part of plant growth and yield decline in drought stress. In order to evaluate the mycorrhizal fungi potential to decline the deleterious effects of drought stress , one greenhouse research with 10 fungal treatments in 3 levels of moisture including 8 , 16 and 32 %(w/w) and 4 replication for each treatments in completely randomized factorial was designed .Parameters such as shoot dry matter, root dry matter, colonization percentage and uptake of P, K Zn, Fe, Mn and Cu were determined. Results showed that moisture treatments had meaningful effect (P<0.01) on all parameters and fungal treatments also had meaningful effects (P<0.01) in colonization percentage and (P<0.05) on shoot dry matter and uptake of P, Zn and Fe .Three fungal species including Glomus mossea, Glomua intraradices and Glomus etunicatum were more effective than other species.