Kati Togliatti, Department of Agronomy, Iowa State University; Andy VanLoocke,
In the future, global population and temperature are predicted to increase, causing greater demand for water and increased competition between agriculture and other important sectors. One way to help meet this demand, is to identify strategies that increase water use efficiency (WUE) which is the ratio of crop production to water uptake. Improving WUE requires a baseline data in water dynamics. While there are lots of data comparing WUE for numerous crops and environments, research isolating evapotranspiration (ET) and WUE from all other environmental factors is limiting. To address this, we conducted a side-by-side evaluation of total ET and WUE of two major crops, maize (corn) and glycine max (soybeans), at a site in the U.S. Corn Belt. ET was determined using micrometeorological measurements, which were replicated for each crop and WUE was calculated using aboveground harvested biomass in the growing season of 2016. Growing season temperatures and precipitation were slightly above climatological normal. Our results indicate that maize concluded with higher cumulative ET but when both canopies are fully developed the two species do not differ significantly in the amount of water used. Maize also concluded with a higher WUE.
Marrs, Emily, "The Differences in Water Use Efficiency between Maize and Soybean in Central Iowa" (2017). Meteorology Senior Theses. 28.