Indicators of water use efficiency across diverse agroecosystems and spatiotemporal scales

Authors: Hoover, David; Abendroth, Lori; Browning, Dawn; SAHA, AMARTYA - Archbold Biological Station; Snyder, Keirith; Wagle, Pradeep; Witthaus, Lindsey; Baffaut, Claire; Biederman, Joel; Bosch, David; BRACHO, ROSVEL - University Of Florida; BUSCH, DENNIS - University Of Wisconsin; Clark, Pat; Ellsworth, Patrick; Fay, Philip; Flerchinger, Gerald; Kearney, Sean; Levers, Lucia; Saliendra, Nicanor; Schmer, Marty; Schomberg, Harry; Scott, Russell - Russ

Submitted to: Science of the Total Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/13/2022
Publication Date: 12/23/2022
Citation: Hoover, D.L., Abendroth, L.J., Browning, D.M., Saha, A., Snyder, K.A., Wagle, P., Witthaus, L.M., Baffaut, C., Biederman, J.A., Bosch, D.D., Bracho, R., Busch, D., Clark, P., Ellsworth, P.Z., Fay, P.A., Flerchinger, G.N., Kearney, S.P., Levers, L.R., Saliendra, N.Z., Schmer, M.R., Schomberg, H.H., Scott, R.L. 2022. Indicators of water use efficiency across diverse agroecosystems and spatiotemporal scales. Science of the Total Environment. 864. Article e160992. https://doi.org/10.1016/j.scitotenv.2022.160992.
DOI: https://doi.org/10.1016/j.scitotenv.2022.160992

Interpretive Summary: Agriculture has the highest demand for water globally and water resources are projected to become impacted by climate change and competition from other demands, such as urbanization. Increasing water use efficiency (WUE) or producing 'more crop per drop' has been a long-term goal of agricultural management, engineering, and innovations. Indicators of WUE in agricultural production can help balance production demands with sustainability goals, but are often complex. In this review, we evaluate the pros and cons of common indicators of WUE in agriculture and suggest ways to apply them within and across agroecosystems. We conclude by suggesting how WUE indicators can adapt agriculture to climate change.

Technical Abstract: Understanding the relationship between water and production within and across agroecosystems is essential for addressing several agricultural challenges of the 21st century: providing food, fuel, and fiber to a growing human population, reducing the environmental impacts of agricultural production, and adapting agroecosystems to climate change. Agriculture, of all human activities, has the highest demand for water globally and therefore increasing water use efficiency (WUE), or producing ‘more crop per drop’, has been a long-term goal of agricultural management, engineering, technological innovations, and crop breeding. WUE is a widely used term applied across a diverse array of spatial and temporal scales, from the leaf to the farm to the dinner table, and from seconds to months to years. The measurement, interpretation, and complexity of the many components of WUE varies enormously across these spatial and temporal scales, challenging comparisons within and across diverse agroecosystems. The goal of this review is to evaluate common indicators of WUE in agricultural production and assess tradeoffs when applying these indicators in agroecosystems with a changing climate. We examine three questions: (1) what are the uses and limitations of common WUE indicators, (2) how to apply WUE indicators within and across agroecosystems, and (3) how can WUE indicators help adapt agriculture to climate change. Addressing these agricultural challenges will require land managers, producers, policy makers, researchers, and consumers to evaluate costs and benefits of practices and innovations of water use in agricultural production. Clearly defining and interpreting WUE in the most scale-appropriate way is crucial for advancing agroecosystem sustainability.