Evaporation Losses and Evapotranspiration Dynamics in Overhead Sprinkler Irrigation

A comprehensive review of evaporation losses and evapotranspiration (ET) dynamics in sprinkler irrigation revealed substantial differences in the magnitudes of the different components of evaporation. Field studies reported that droplet evaporation losses ranged from 0.5%-45%, whereas theoretical studies indicated losses of less than 1%. A recent experimental study using advanced instruments and methodologies estimated that canopy evaporation is the major evaporation loss and droplet evaporation could be assumed to be negligible. Other studies showed that evaporation increased and transpiration decreased in evapotranspiration dynamics during wet canopy conditions. Sensible and latent heat fluxes in sprinkler irrigated crops act in opposite ways, but both positively contribute to the available energy and total ET.