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New Evapotranspiration Crop Coefficients

Wright, James L. (1982) New Evapotranspiration Crop Coefficients. Proceedings of the American Society of Civil Engineers, Journal of the Irrigation and Drainage Division. 108(IR2):57-74.

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Abstract

Improved crop coefficients for various Pacific Northwest irrigated
crops were developed for estimating crop evapotranspiration (ET) from estimates
or measurements of reference ET. Reference ET was based on that
for well watered, actively growing alfalfa with sufficient growth for near
maximum ET in arid, irrigated regions. ET for the alfalfa reference crop and
other crops was measured with sensitive weighing lysimeters at a ?eld site
near Kimberly, Idaho. The new crop coefficients are basal or minimal coefficients
for conditions when soil evaporation is minimal but root-zone soil moisture
is adequate. When combined with improved estimates of evaporation from
wet soils, they should permit more accurate estimates of daily crop ET, more
accurate irrigation scheduling, and more reliable estimates of crop water
requirements. Curves were developed for alfalfa, potatoes, snap beans, sugarbeets,
peas, sweet and field corn and winter and spring cereals.

Item Type: Article
NWISRL Publication Number: 0478
Subjects: Water > Evapotranspiration
Mass Import - autoclassified (may be erroneous)
Depositing User: Dan Stieneke
Date Deposited: 20 Nov 2010 21:52
Last Modified: 25 Jan 2017 18:46
Item ID: 382
URI: https://eprints.nwisrl.ars.usda.gov/id/eprint/382