Command Area Water Demands. II: Water‐Demand Function
Publication: Journal of Irrigation and Drainage Engineering
Volume 120, Issue 6
Abstract
The cumulative water demand (CWD) curve was used for validating and calibrating the unit command area (UCA) model, which predicts the aggregate water demands of individual command areas for the entire crop season. During the model calibration process, as presented in the companion paper, three important variables in the operation stage on the prediction of demand were found to be dominant in determining the CWD curve profile. The logistic function with three parameters, which is a particular form of the exponential‐type function, was adopted for fitting the CWD curve. High correlations were observed between the individual curve parameters and the field variables. Three parameters are management‐allowable depletion (MAD), irrigation application uniformity (IAU), and initial soil moisture (ISM). Effectiveness of the equation developed for a particular UCA using the regression analysis was successfully demonstrated, and applicability for some other UCAs in the same water system was also recognized.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Brooke, A., Kendrick, D., and Meeraus, A. (1988). GAMS; a user's guide. The Scientific Press, Redwood City, Calif.
2.
Cheney, E. W., and Kincaid, D. R. (1985). Numerical mathematics and computing. Cole Publishing Co., Pacific Grove, Calif.
3.
Giordano, F. R., and Weir, M. D. (1991). Differential equations. Addison‐Wesley Publishing Co., Inc., Reading, Mass.
4.
Keller, A. A. (1987). “The USU unit command area model.” Water Mgmt. Synthesis II Rep #71, Utah State University, Logan, Utah.
5.
McCann, R. C. (1982). Introduction to ordinary differential equations. Harcourt Brace Jovanvich, Inc., New York, N.Y.
6.
Norusis, M. J. (1988). SPSS/PC+ advanced statistics V2.0. SPSS Inc. Chicago, Ill.
7.
Thompson, W. J. (1992). Computing for scientists and engineers. John Wiley & Sons, Inc., New York, N.Y.
8.
U.S. Dept. of Agriculture (USDA), Soil Conservation Service, and U.S. Dept. of the Interior Bureau of Land Management. (1977). Rep., Soil Survey of Delta Area. Utah Agricultural Experimental Station, Utah.
9.
Yamashita, S. (1990). “Validation and calibration of the USU unit command area model,” PhD thesis, Utah State University, Logan, Utah.
10.
Yamashita, S., and Walker, W. R. (1994). “Command area water demands. I: validation and calibration of UCA model.” J. Irrig. and Drain. Engrg., ASCE, 120(6), 1025–1042.
Information & Authors
Information
Published In
Journal of Irrigation and Drainage Engineering
Volume 120 • Issue 6 • November 1994
Pages: 1043 - 1055
Copyright
Copyright © 1994 American Society of Civil Engineers.
History
Received: Sep 22, 1992
Published online: Nov 1, 1994
Published in print: Nov 1994
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.