ESTIMATION OF EVAPOTRANSPIRATION AND IRRIGATION UNIFORMITY FROM SUBSOIL SALINITY (ARIZONA).

Persistent Link:
http://hdl.handle.net/10150/188001
Title:
ESTIMATION OF EVAPOTRANSPIRATION AND IRRIGATION UNIFORMITY FROM SUBSOIL SALINITY (ARIZONA).
Author:
HASSAN, HESHAM MAHMOUD.
Issue Date:
1985
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Irrigation uniformity, efficiency, leaching fraction, salt and water ages, and evapotranspiration rate were estimated from subsoil salinity data for three cotton fields in Arizona. The estimation of these parameters was based on the assumption of steady-state water and salt flow through the crop root zone. The levels of salt concentration in the irrigation water were 21.3, 11.5, and 11.6 meq/L for Fields 1, 2, and 3, respectively. Two of these fields were furrow irrigated, and the third was subsurface drip irrigated. Each field was sampled for salt concentrations to a depth of 1.5 m at 10-15 sites. A total of 514 soil samples were collected. Significantly lower salt concentrations were observed in the soil profiles in Fields 1 and 2 compared to Field 3, but lower variations in the salt concentrations were observed in Field 3 compared with Fields 1 and 2. These variations in salt concentration could be due to restricted water movement within the soil profile caused by stratified soil. Since a soil-water extract model indicated little or no chemical precipitation of salt within the soil profile, there was no need to correct the data for chemical effects. The calculated irrigation uniformity was highest in Field 3 and lowest in Field 1. This may be related to more accurate land leveling in field 2 than Field 1. The irrigation efficiencies were 83.0%, 89.0%, and 80.0% for Fields 1, 2, and 3, respectively. The correlation coefficient between the ages of salt and water was 0.98, 0.99, and 0.97 for Fields 1, 2, and 3, respectively. Leaching fraction was highest in Field 3 and lowest in Field 2. Mean actual ET calculated from the Blaney-Criddle method were 372, 314, and 308 mm for Fields 1, 2, and 3, respectively. Mean ET calculated from the salinity data were 1,250, 1,590, and 1,140 mm for Fields 1, 2, and 3, respectively. Statistically significant correlation coefficients were, however, found between both methods of estimating ET. These values were 0.97, 0.86, and 0.93 for Fields 1, 2, and 3, respectively.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Soils, Salts in -- Measurement.; Evapotranspiration.; University of Arizona. Safford Agricultural Center.; Maricopa Agricultural Center.; Howard Wuertz Farm (Pinal Co., Ariz.)
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Soils, Water and Engineering; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Matthias, A. D.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleESTIMATION OF EVAPOTRANSPIRATION AND IRRIGATION UNIFORMITY FROM SUBSOIL SALINITY (ARIZONA).en_US
dc.creatorHASSAN, HESHAM MAHMOUD.en_US
dc.contributor.authorHASSAN, HESHAM MAHMOUD.en_US
dc.date.issued1985en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractIrrigation uniformity, efficiency, leaching fraction, salt and water ages, and evapotranspiration rate were estimated from subsoil salinity data for three cotton fields in Arizona. The estimation of these parameters was based on the assumption of steady-state water and salt flow through the crop root zone. The levels of salt concentration in the irrigation water were 21.3, 11.5, and 11.6 meq/L for Fields 1, 2, and 3, respectively. Two of these fields were furrow irrigated, and the third was subsurface drip irrigated. Each field was sampled for salt concentrations to a depth of 1.5 m at 10-15 sites. A total of 514 soil samples were collected. Significantly lower salt concentrations were observed in the soil profiles in Fields 1 and 2 compared to Field 3, but lower variations in the salt concentrations were observed in Field 3 compared with Fields 1 and 2. These variations in salt concentration could be due to restricted water movement within the soil profile caused by stratified soil. Since a soil-water extract model indicated little or no chemical precipitation of salt within the soil profile, there was no need to correct the data for chemical effects. The calculated irrigation uniformity was highest in Field 3 and lowest in Field 1. This may be related to more accurate land leveling in field 2 than Field 1. The irrigation efficiencies were 83.0%, 89.0%, and 80.0% for Fields 1, 2, and 3, respectively. The correlation coefficient between the ages of salt and water was 0.98, 0.99, and 0.97 for Fields 1, 2, and 3, respectively. Leaching fraction was highest in Field 3 and lowest in Field 2. Mean actual ET calculated from the Blaney-Criddle method were 372, 314, and 308 mm for Fields 1, 2, and 3, respectively. Mean ET calculated from the salinity data were 1,250, 1,590, and 1,140 mm for Fields 1, 2, and 3, respectively. Statistically significant correlation coefficients were, however, found between both methods of estimating ET. These values were 0.97, 0.86, and 0.93 for Fields 1, 2, and 3, respectively.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectSoils, Salts in -- Measurement.en_US
dc.subjectEvapotranspiration.en_US
dc.subjectUniversity of Arizona. Safford Agricultural Center.en_US
dc.subjectMaricopa Agricultural Center.en_US
dc.subjectHoward Wuertz Farm (Pinal Co., Ariz.)en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineSoils, Water and Engineeringen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorMatthias, A. D.en_US
dc.contributor.committeememberDutt, G. R.en_US
dc.contributor.committeememberThames, J. L.en_US
dc.contributor.committeememberFfolliott, P.en_US
dc.identifier.proquest8522812en_US
dc.identifier.oclc696424884en_US
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