Mehdi Jafari talukolaee; Rassol Nouri Khajebelagh
Abstract
The present study was conducted with the aim of investigating the productivity and energy indicators of paddy, wheat, fodder corn, seed corn and citrus fruits in the Tajan plain in the crop year 1401-02. Then sampling was done based on 300 designed questionnaires. The collected information includes man-days, ...
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The present study was conducted with the aim of investigating the productivity and energy indicators of paddy, wheat, fodder corn, seed corn and citrus fruits in the Tajan plain in the crop year 1401-02. Then sampling was done based on 300 designed questionnaires. The collected information includes man-days, working hours of machinery, fuel consumption of machinery, consumption of nitrogen, phosphate, potassium fertilizers, consumption of various types of chemical pesticides, including herbicides and fungi. Pesticides and insecticides were in liters per hectare, the amount of water consumed was in cubic meters per hectare, the amount of seeds consumed was in kilograms per hectare and the amount of production. The results showed that the highest amount of energy in Tajan plain in the input energy sector for paddy crop (593256 mega joules per hectare), output energy for fodder corn product (141795 mega joules per hectare), net energy for fodder corn product (110758.53 mega joules per hectare) and energy efficiency was also for fodder corn product (1.1 kg/mega joules). Also, according to the obtained results, it was found that in all the products, the four inputs of water consumption, nitrogen fertilizer, machinery and fuel have the highest amount. The results of the investigation of the physical productivity of water showed that the highest productivity in the Tajan plain is related to fodder corn and the lowest productivity is related to rice 0.5 kg/m3. In general, to increase the productivity of lands and products in terms of productivity and energy indicators, it is necessary to use the cultivation of plants with appropriate performance, the highest level of productivity and the lowest level of input consumption. research, fodder corn had more suitable conditions.
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Norollah Jalali; Ali Shahnazari; MZ Ahamadi; Mojtaba Khoshravesh; Mojtaba Rezaie
Abstract
The purpose of this study was to investigate the effects of irrigation management on water requirement and crop coefficient of Hashemi and Kuhsar cultivars in the first crop. This experiment was carried out in Mahmoudabad District of Mazandaran Province in Iran in the form of factorial in a randomized ...
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The purpose of this study was to investigate the effects of irrigation management on water requirement and crop coefficient of Hashemi and Kuhsar cultivars in the first crop. This experiment was carried out in Mahmoudabad District of Mazandaran Province in Iran in the form of factorial in a randomized complete block design, in two growing seasons of 2016-2018. The water requirements for the fields (from transplanting to harvest) and the crop coefficient of these two cultivars were studied in two systems of traditional flooding and system of rice intensification (SRI). The results showed that, in the first crop, the two-year average water requirements of Kohsar and Hashemi in SRI were 534 and 556 mm and for the traditional flooding system 623 and 632 mm, respectively. The water required by the farm in traditional flooding decreased by 13.1% in the SRI. Based on reference evapotranspiration using pan evaporation method for the three stages of vegetative, reproductive, and maturing, crop coefficient values for the flooding system for Kuhsar were, respectively, 1.14, 1.29, and 0.92; and for Hashemi, they were 1.18, 1.32, and 0.92. According to the obtained results, SRI causes significant savings in paddy water consumption, therefore, it is suggested that, due to water shortage in the country, this method be used as one of the adaptation strategies in rice fields.
mostafa yosefian; Ali Shahnazari; mirkhalegh ziyatabar ahmadi; mahmoud raeini; Behroz arabzadeh
Abstract
Due to drought crisis in recent years, the use of alternative cropping methods that save water without any decrease in yield is increasing. Therefore, in order to evaluate the yield, yield components, and water use of rice under different non-submerged water levels and comparing it with permanently submerged ...
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Due to drought crisis in recent years, the use of alternative cropping methods that save water without any decrease in yield is increasing. Therefore, in order to evaluate the yield, yield components, and water use of rice under different non-submerged water levels and comparing it with permanently submerged condition, an experiment was conducted at fields of Rice Research Institute of Mazandaran during 2015 and 2016, using a randomized complete block design with three replications. The treatments consisted of two methods, regulated deficit irrigation (RDI) by irrigating all furrows and partial root drying (PRD) by irrigating alternate furrows, with three levels of drought stress: 10, 30, and 60 KPa (RDI10, PRD10, RDI30, PRD30, RDI60, PRD60) and a control treatment with permanently submerged basin irrigation in puddled soil (traditional method). Rice yield, yield components, and water consumption were measured in each treatment. The results showed that yield, plant height, panicle length, number of grains, 1000-grain weight, and water productivity (kg/m3) and water consumption at different levels of irrigation had a statistically significant difference in different treatments. Although the highest yield of rice was obtained in continuous submergence, yield reduction in alternate furrow irrigation treatments with minor stress (RDI10 and PRD10) was negligible and they were in the same statistical group in the two years of study. Also, partial root drying, significantly reduced water consumption, such that PRD10 treatment resulted in 32% reduction in water consumption compared to the control treatment, and deficit irrigation, especially partial root drying, increased water productivity. The highest water productivity (kg/m3) was calculated in PRD30 treatment at 0.724 kg per cubic meter of water. Based on the results, water consumption in the partial root drying was less than regulated deficit irrigation with the same tension, such that water consumption in PRD10 decreased by 15% compared to RDI10. However, average yield of PRD10v in both years was 1.1% higher. The results related to the yield components were also proportional to yield and partial root drying method compared to regulated deficit irrigation was better.
peyman mokhtari motlagh; Ali Shahnazari; mohammadreza noori
Abstract
Evaluation of soil moisture transfer between two subsurface drains and water drainage from the roots is very important. In this regard, application of conservation of mass equations by HYDRUS-2D software, in addition to reducing costs, could speed up access to the results. In this study, a subsurface ...
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Evaluation of soil moisture transfer between two subsurface drains and water drainage from the roots is very important. In this regard, application of conservation of mass equations by HYDRUS-2D software, in addition to reducing costs, could speed up access to the results. In this study, a subsurface drainage systems with drain depth of 0.9 m, drain spacing of 30 m, and groundwater depth of 50 cm was studied during one growing season of canola in paddy fields located in Sari region. Soil profile was considered from the surface to a depth of two meters and six layers of soil were defined. Soil saturated hydraulic conductivity (K) for each of the 6 layers of the soil was calculated by Piezometric method and using Kirkham equation. The K values for the surface layer down to the layer at the depth of 2 m were, respectively, 0.8, 0.11, 0.29, 0.16, 0.38 and 0.083 m/day. Other input parameters of HYDRUS-2D model were measured every day including precipitation, water table depth, and soil moisture. Observed data and simulated water tables between the two drain pipes were compared and the model was calibrated in saturated period. The performance of the model was evaluated by statistical approaches considering root mean square error (RMSE), the coefficient of determination (R2), the average deviation (AD) percent error (PE) and the modeling efficiency (EF), which were 0.0214 cm3/cm3, 0.932, 0.0407 cm3/cm3, 0.079, and 0.525, respectively. The results showed that simulation was considerably satisfactory.
moazam khaleghi; Ali Shahnazari; farzad hasanpour; F K
Abstract
The scarcity of freshwater and increasing water demand for irrigation has led to the application of new irrigation methods and also use of saline water resources. For this purpose, a field study was conducted in two crop seasons (2014 and 2015) for evaluating the effect of quantity and quality ...
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The scarcity of freshwater and increasing water demand for irrigation has led to the application of new irrigation methods and also use of saline water resources. For this purpose, a field study was conducted in two crop seasons (2014 and 2015) for evaluating the effect of quantity and quality of irrigation water on morphological attributes and quality of sunflower in the experimental farm of Sari Agricultural Sciences and Natural Resources University. Treatments were arranged as factorial based on randomized complete block design with three replications. treatments included full irrigation with fresh water (FI), full irrigation with saline water (SI), full irrigation with alternative use of saline water and fresh water (FSI), partial root zone drying irrigation with fresh water (PRD1), partial root zone drying irrigation with saline water (PRD2) and partial root zone drying irrigation with alternative use of saline and fresh water (PRD3). Saline water with an electrical conductivity of 5.4 dS/m was obtained from 20 percent mixing of Caspian seawater with fresh water. The results showed that, in most morphological characteristics, significant difference was not found between the treatments of PRD1, PRD3 and FSI compared with FI. The highest oil content (56%) was obtained from PRD2 and PRD3. SI treatment had the lowest oil content. The maximum oil yield was found in treatments FI and PRD1 with amounts of 1831 and 1783.5 kg per ha, respectively. The lowest level of oil and protein yield was found in PRD2 and SI treatments in both years. It could be concluded that in the water crisis condition and the need to use less water or saline water instead of fresh water, PRD3 and FSI methods are recommendable as the optimal management.
s d; Ali Shahnazari; Mehdi Jafari talukolaee
Abstract
Subsurface drainage is a prerequisite to growing winter crops and improving water management in rice season in the consolidated paddy fields in Northern Iran. Based on different cultivation condition, to decrease nutrient loss from subsurface drainage in these fields, adopting suitable strategies will ...
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Subsurface drainage is a prerequisite to growing winter crops and improving water management in rice season in the consolidated paddy fields in Northern Iran. Based on different cultivation condition, to decrease nutrient loss from subsurface drainage in these fields, adopting suitable strategies will decrease the pollution of water resources. A research was conducted in pilot farm of Sari Agricultural Sciences and Natural Resources University from May 2015 to April 2016 (during two successive rice-canola growing seasons) to evaluate the effect of subsurface drainage systems on nitrate loss and nitrate concentration in different soil depths. The subsurface drainage treatments were three existing subsurface drainage systems with mineral envelopes, including systems with 30-m spacing and 0.9 m depth, a drainage system with 30-m spacing and 0.65 m depth, a drainage system with 15-m spacing and 0.65 m depth, and a bi-level subsurface drainage system with drain spacing of 15 m and drain depths of 0.65 and 0.9 m as alternate depths (bi-level). The nitrate concentration was monitored in drainage water and at depths of 0.4, 0.9, 2 and 5 m during the study period. The results showed that the nitrate concentration and the total nitrate loss during rice growing season was 33-80% and 91-99 %, respectively, less than that in canola growing season. Also, the nitrate concentration in drainage water for drains with 0.9 m depth was more than that in drains with 0.65 m depth. On the other hand, nitrate concentration in surface depth was higher than lower depths in all treatments. Overall, in both seasons, drainage system with wider spacing and shallower depth drained out less nitrate than the other systems.