|Evett, Steven - Steve|
|ANDRADE, ALEJANDRO - Orise Fellow|
|Brauer, David - Dave|
Submitted to: Alfalfa National Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/2/2015
Publication Date: 12/3/2015
Citation: Evett, S.R., Oshaughnessy, S.A., Andrade, A., Brauer, D.K., Colaizzi, P.D., Schwartz, R.C. 2015. Strategies to improve water productivity in a water-stressed future. Alfalfa National Symposium Proceedings. Western Alfalfa and Forage Symposium, December 4, 2015, Reno, Nevada.
Interpretive Summary: Maintaining high yields in a water-short future that western states in the U.S. are facing will require increases in the yield per unit of water consumed by the crop. Scientists and engineers at the USDA-ARS Conservation and Production Research Laboratory, Bushland, Texas, have developed several methods for improving water productivity. Converting to pressurized irrigation systems in the U.S. has reduced water use overall from more than 24 inches to less than 19 inches (all crops). Adoption of micro-irrigation, typically subsurface drip irrigation for forage crop such as alfalfa, will improve efficiency even further by reducing evaporative losses of water from the soil surface. There are new and more accurate sensor systems that wirelessly transfer data out of the field to farm headquarters to guide irrigation scheduling. When these sensor networks are tied into computerized decision support systems, irrigation can be scheduled automatically, reducing management time and improving water use efficiency. The principles and technologies discussed in this presentation can be readily adapted for use in forage production in the western U.S. to meet needs of a significant cattle industry.
Technical Abstract: As water shortages become more commonplace, strategies to increase crop water productivity are increasingly sought by producers. Common strategies include increasing irrigation application efficiency, changing irrigation application methods, improving irrigation scheduling, using sensing systems to guide management, changing forage crops, and managing for moderate, controlled deficit irrigation. These strategies improve productivity by reducing runoff and deep percolation losses, applying water more uniformly so that severe deficits do not occur in some parts of the field and waterlogging in other parts, reducing evaporative losses of water by applying water close to or beneath the soil surface, changing the crop-specific transpiration efficiency, and managing for maximum water use efficiency (unit of yield per unit of water consumed) rather than maximum yield. This paper discusses examples of the use of one or more of these strategies to successfully increase water productivity of forage crops.