Consumptive Water Use and Efficiency of Irrigated U.S. Corn: Learning From Hundreds of Site‐Management‐Year Observations
Year: 2024
Type: article
Abstract: Grain yield response to consumptive water use a.k.a. evapotranspiration (ETc) is a critical dimension of food‐water nexus in irrigated agroecosystems. With the largest water footprint, irrigated corn production in the U.S. must be assessed for its ETc and water use efficiency (WUE) at a scale meaningful for producers and water managers. Field experiments significantly inform our understanding of how corn yield responds to ETc at the field/plot‐level, but their collective synergism remains untapped. This analysis uses a literature synthesis of existing measured data from nationwide experiments that measured corn ETc, to build models that elucidate and predict corn ETc and WUE under diverse environment and on‐farm management. The resulting synthesis (n = 1,362) captured wide ranging conditions of mean aridity, environmental variability, management, and crop outcomes, providing an unprecedented opportunity to train data‐driven models. Random forest models effectively predicted seasonal total ETc and seasonal mean WUE using a handful of environmental and management‐based predictors, demonstrating RMSEs of 33 mm (5.1%) and 0.28 kg m−3 (10.4%), respectively. Irrigation depth was the most important followed by total precipitation received during the growing season in determining ETc and WUE. Trained on the largest compilation of experimental data sets of corn ETc, these data‐driven models represent nuanced corn water production functions that also account for weather and agronomy besides describing economic yield‐ETc response.
Source: Water Resources Research
DOI: 10.1029/2024wr037434
Author: Meetpal S. Kukal
Institution: University of Idaho
Language: English
Subfield: Soil Science
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $3,000
OpenAlex ID: W4401648930