Evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and FAO method

Precise estimation of daily crop reference evapotranspiration and crop coefficients (K c) is required for determining crop water use in order to practice proper irrigation management. Crop coefficients, which have been presented for most crops by FAO based on four crop stages (initial, development,...

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Main Authors: Mirzaei, Majid, Sohrabi, Teymour, Jahanbania, Heerbod, Faghih, Mina, Lee, Teang Shui
Format: Article
Language:English
Published: American-Eurasian Network for Scientific Information 2011
Online Access:http://psasir.upm.edu.my/id/eprint/23150/
http://psasir.upm.edu.my/id/eprint/23150/1/Evaluation%20of%20evapotranspiration%20coefficient%20and%20daily%20crop%20reference%20evapotranspiration%20in%20a%20semi-arid%20region%20based%20on%20field%20water%20balance%20and%20FAO%20method.pdf
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author Mirzaei, Majid
Sohrabi, Teymour
Jahanbania, Heerbod
Faghih, Mina
Lee, Teang Shui
author_facet Mirzaei, Majid
Sohrabi, Teymour
Jahanbania, Heerbod
Faghih, Mina
Lee, Teang Shui
author_sort Mirzaei, Majid
building UPM Institutional Repository
collection Online Access
description Precise estimation of daily crop reference evapotranspiration and crop coefficients (K c) is required for determining crop water use in order to practice proper irrigation management. Crop coefficients, which have been presented for most crops by FAO based on four crop stages (initial, development, middle, and late) are affected by many factors including soil moisture, growing degree days (GDD) and leaf area index (LAI). Therefore, the above-mentioned factors have to be considered in estimating these values. The purpose of this study was evolution of crop coefficients for sugar beet crop based on field water balance and FAO method through measuring soil moisture variation, and evaluating reference ET by FAO-penman-monteith equation in a semi-arid region. Crop coefficient curves and various mathematical relationships were developed for growth period to estimate the crop coefficient for this crop. The K c values during the growing season was 0.59, 1.19 and 0.85 for initial, mid and end stage respectively. The K c ini that was estimated with field water balance method was greater than FAO method but K c mid, K c end were lesser than FAO method over the growth season.
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language English
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spelling upm-231502015-12-09T06:27:49Z http://psasir.upm.edu.my/id/eprint/23150/ Evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and FAO method Mirzaei, Majid Sohrabi, Teymour Jahanbania, Heerbod Faghih, Mina Lee, Teang Shui Precise estimation of daily crop reference evapotranspiration and crop coefficients (K c) is required for determining crop water use in order to practice proper irrigation management. Crop coefficients, which have been presented for most crops by FAO based on four crop stages (initial, development, middle, and late) are affected by many factors including soil moisture, growing degree days (GDD) and leaf area index (LAI). Therefore, the above-mentioned factors have to be considered in estimating these values. The purpose of this study was evolution of crop coefficients for sugar beet crop based on field water balance and FAO method through measuring soil moisture variation, and evaluating reference ET by FAO-penman-monteith equation in a semi-arid region. Crop coefficient curves and various mathematical relationships were developed for growth period to estimate the crop coefficient for this crop. The K c values during the growing season was 0.59, 1.19 and 0.85 for initial, mid and end stage respectively. The K c ini that was estimated with field water balance method was greater than FAO method but K c mid, K c end were lesser than FAO method over the growth season. American-Eurasian Network for Scientific Information 2011-12 Article PeerReviewed application/pdf en http://psasir.upm.edu.my/id/eprint/23150/1/Evaluation%20of%20evapotranspiration%20coefficient%20and%20daily%20crop%20reference%20evapotranspiration%20in%20a%20semi-arid%20region%20based%20on%20field%20water%20balance%20and%20FAO%20method.pdf Mirzaei, Majid and Sohrabi, Teymour and Jahanbania, Heerbod and Faghih, Mina and Lee, Teang Shui (2011) Evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and FAO method. Australian Journal of Basic and Applied Sciences, 5 (12). pp. 1850-1856. ISSN 1991-8178 http://ajbasweb.com/old/ajbas_December_2011.html
spellingShingle Mirzaei, Majid
Sohrabi, Teymour
Jahanbania, Heerbod
Faghih, Mina
Lee, Teang Shui
Evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and FAO method
title Evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and FAO method
title_full Evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and FAO method
title_fullStr Evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and FAO method
title_full_unstemmed Evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and FAO method
title_short Evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and FAO method
title_sort evaluation of evapotranspiration coefficient and daily crop reference evapotranspiration in a semi-arid region based on field water balance and fao method
url http://psasir.upm.edu.my/id/eprint/23150/
http://psasir.upm.edu.my/id/eprint/23150/
http://psasir.upm.edu.my/id/eprint/23150/1/Evaluation%20of%20evapotranspiration%20coefficient%20and%20daily%20crop%20reference%20evapotranspiration%20in%20a%20semi-arid%20region%20based%20on%20field%20water%20balance%20and%20FAO%20method.pdf