|Thompson, A - UNIV. OF MISSOURI|
|Martin, D - UNIV. OF NEBRASKA|
|Norman, J - UNIV. OF WISCONSIN|
Submitted to: American Society of Agricultural Engineers Meetings Papers
Publication Type: Other
Publication Acceptance Date: June 18, 1995
Publication Date: N/A
Technical Abstract: Application losses from sprinkler systems are affected by many factors including the environment, application method, and time of day of the application. The Cupid-DPE water droplet evaporation and plant/energy balance model was used to evaluate the effect of irrigation timing on water application efficiency of sprinkler irrigation of a plant canopy. Comparisons were based on irrigation of corn under identical conditions of leaf area index (LAI), plant height, and initial soil water content using the same irrigation system characteristics and application "gross" depth, but applied at different times of the day. Model estimates of soil evaporation and total evapotranspiration (ET) were made. Results indicate that benefits of irrigating at night versus daytime were dependent on the initial soil water content, LAI, wind speed, and solar radiation. Depending on the duration of leaf wetness and soil water content, the reduction in water loss from irrigating at night can be shifted to greater ET on the following day resulting in similar total ET values over a 24-h period. Direct evaporation of water droplets was reduced by nighttime irrigation, but this was not an important savings since it represented less than 1% of the total loss even when irrigating during the day.