Wind effects on solid set sprinkler irrigation depth and corn yield

Abstract

A field experiment was performed to study the effect of the space and time variability of water application on solid set sprinkler irrigated corn yield. A solid set sprinkler irrigation setup – typical of the new irrigation developments in the Ebro basin of Spain – was considered. Analyses were performed to (1) study the variability of the water application depth in each irrigation event and in the seasonal irrigation, and (2) relate the spatial variability in crop yield with the variability of the applied irrigation and with the soil physical properties. The results of this research showed that a significant portion of the Christiansen coefficient of uniformity (CU) variability, wind drift and evaporation losses were explained by the wind speed alone. The seasonal irrigation uniformity (CU of 88 %) was higher than the average uniformity of the individual irrigation events (CU of 80 %). No evidence has been found proving that the soil diminishes the heterogeneity induced by the irrigation water distribution. The uniformity of soil water recharge was lower than the irrigation uniformity and the relationship between both variables was statistically significant. Results indicated that grain yield (GY) variability was partly dictated by the water deficit resulting from the non-uniformity of water distribution during the crop season. The uniformity of the irrigation events applied beyond the flowering stage was correlated with grain yield, indicating that in this period a proper selection of the wind conditions is required in order to attain high yield in sprinkler irrigated corn.