Location: Soil and Water Management ResearchTitle: Evaporative losses from sprinkler and subsurface drip irrigation in a region of large evaporative demand Author
|Evett, Steven - Steve|
|Moorhead, Jerry - Jed|
|Brauer, David - Dave|
Submitted to: ASABE Annual International Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2018
Publication Date: 8/1/2018
Citation: Evett, S.R., Colaizzi, P.D., Marek, G.W., Moorhead, J.E., Brauer, D.K., Copeland, K.S., Ruthardt, B.B. 2018. Evaporative losses from sprinkler and subsurface drip irrigation in a region of large evaporative demand [abstract]. ASABE Annual International Meeting. Paper No. 1801788.
Technical Abstract: Mid elevation spray application (MESA) is the most common center pivot sprinkler irrigation application method in the Southern High Plains. Spray plates are typically at 5 ft (1.5 m) elevation above the soil surface and spaced along the sprinkler system lateral by 5 ft (1.5) or similar distance to achieve uniform coverage of the soil. The sprays wet the soil and crop completely during pre-season irrigations or irrigations before the crop reaches 5 ft in height. Water evaporated from the soil and crop is lost and does not contribute to yield formation. The Southern High Plains is a semi-arid region that experiences dry, often hot winds that exacerbate evaporative losses, and subsurface drip irrigation (SDI) has been introduced to put irrigation water in the crop root zone without wetting the soil surface and crop leaves. Scientists at the USDA ARS Conservation & Production Research Laboratory, Bushland, Texas, compared grain corn yield and water use between MESA and SDI for two years, 2013 and 2016 using two large weighing lysimeters irrigated using SDI and two irrigated using MESA. SDI reduced evaporative (E) losses by 138 to 151 mm (5.4 to 5.9 inch) per corn season. Evaporative loss reductions occurred both early and in midseason. Evaporative loss was less when the crop was taller than the elevation of the sprinklers (mid-season maize) – indicating that low elevation spray application (LESA) and low energy precision application (LEPA) methods could fare better than MESA. Using SDI reduced overall corn (maize) water use by 17 to 18% while increasing yield by 0 to 20% and water use efficiency by 18 to 46%.