Development and Evaluation of Evapotranspiration Models for Irrigation Scheduling

Wright, James L. and Jensen, Marvin E. (1978) Development and Evaluation of Evapotranspiration Models for Irrigation Scheduling. Transaction of the ASAE. 21(1):88-91,96.

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Abstract

EVAPOTRANSPIRATION (ET) data for irrigated crops
in southern Idaho were used to develop
relationships for estimating net radiation and
potential ET for the USDA-ARS Computerized Irrigation
Scheduling Program. ET estimated with the
initial relationships compared well with recent measurements
obtained with two sensitive weighing lysimeters.
The:average daily measured Et for alfalfa for 128
days when there was full cover was 7.23 mm, while the
average daily estimated ET was 7.15 mm.

Crop curve relationships were developed from the
ET results for snap beans (Phaseolus vulgaris L). The
depletion of soil water was predicted for two years of
irrigated beans with the scheduling program using
the improved crop curves and compared with the measured
as a test of its performance. The standard deviation
of the difference between predicted and measured
was about 0.95 mm/day from planting until harvest.
The results also demonstrated the importance of obtaining
representative meteorological data for irrigation
scheduling.

Item Type:	Article
NWISRL Publication Number:	0393
Subjects:	Irrigation > Irrigation scheduling Water > Evapotranspiration Research methodology Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:51
Last Modified:	02 Feb 2017 22:27
Item ID:	331
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/331