Evapotranspiration and irrigation water requirements

Wright, James L. (1985) Evapotranspiration and irrigation water requirements. pp. 105-113. In: Proc. Natl. ASAE Conf. Advances in Evapotranspiration. USA-IL-Chicago, 1985/12/16-17.

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Abstract

Basic factors controlling the evapotranspiration process for irrigated crops
are similar to those for other plant communities, except that the water
requirement is largely satisfied by irrigation rather than by precipitation.
A natural consequence of crop growth is the withdrawal of soil water from the
crop root zone, accompanying the evaporative loss of water from exposed plant
and soil surfaces, with the water vapor subsequently being carried away in
the atmospheric air flow. We have traditionally come to speak of this
evaporative water loss as evapotranspiration, or ET for short, though the
process is strictly evaporation, whether from plant or soil surfaces
(McIlroy, 1984). The aim of efficient and effective irrigation management is
to provide sufficient water to a growing crop to replenish depleted soil
water in time to avoid physiological water stress in the growing plants.
Meeting this objective requires knowing when to irrigate and for how long or
how much water to apply. The determination of irrigation requirements is
thus of major importance in providing desirable irrigation management in arid
and semiarid climates, or humid or subhumid climates where irrigation
supplements precipitation.

Item Type:	Conference or Workshop Item (Paper)
NWISRL Publication Number:	0632
Subjects:	Water > Evapotranspiration Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:55
Last Modified:	22 Dec 2016 15:59
Item ID:	877
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/877