Document Type : Research Paper
Authors
1
Assistant Prof., Soil and Water Research Institute, Agricultural Education and Extension Research Organization, Karaj, Iran.
2
Associate Professor of Irrigation and Soil Physics Department, Soil and Water Research Institute, Agricultural Research, Education and Extension Organization, Karaj, Iran
3
Assistant Professor of Irrigation and Drainage, Soil and Water Research Institute, Department of Irrigation and Soil Physics
Abstract
In this research, the effect of climate (rainfall), soil (texture) and irrigation management (irrigation system and efficiency) on the amount and frequency of wheat irrigation in Alborz Province was investigated. For this purpose, wheat irrigation planning at two times and amount of rainfall, in three soil textures (loam, sandy loam and clay loam), for gravity, sprinkler, and drip irrigation systems and different irrigation efficiencies were estimated. Results showed that 7537, 4951 and 4959 m3/ha of water should be available for wheat in 8, 14, and 17 times in gravity, sprinkler, and drip irrigation systems, respectively. Also, the results showed that the differences in soil texture did not change the volume of irrigation water, but the number of irrigations in light soils was more than in heavy soils. Based on this, the amounts of water needed in the three soils of sandy loam, loam, and clay loam were 7987, 7537 and 7988 m3/ha, and the number of irrigations were 10, 8, and 7, respectively. Unlike the soil texture, the efficiency of irrigation water application changed both the volume and the number of irrigations, so that in those three soils with an efficiency of 30%, 46% and 45%, the amount of water required was 12247, 7537 and 8188 m3/ha, respectively. Effective rainfall, like irrigation efficiency, affected irrigation planning depending on the time and amount of rainfall, so that in loam soil with the same rainfall but in two different dates, different amounts of irrigation water were obtained. Therefore, in wheat irrigation planning, attention should be paid to the soil texture, irrigation efficiency, irrigation management, and effective rainfall.
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