By Mark Marsalis: Ag Sense
Declining groundwater levels in the New Mexico High Plains are threatening the sustainability of highly productive irrigated agriculture, which is the foundation for economic stability in the region.
With reduced amounts of irrigation water available to producers, it is imperative maximum water use efficiency be achieved in order for farmers to maintain a level of productivity necessary for continued feed and food supply.
A three-year demonstration project at the New Mexico State University Agricultural Science Center in Clovis will feature the water and energy-conserving abilities of subsurface drip irrigation and geographic information systems/global positioning systems in cropping practices in the region.
Subsurface drip irrigation has been shown to reduce water usage and losses from cropping systems in various regions of the world. It is well documented SDI is highly efficient (greater than 95 percent) at supplying water to plants, even more so than low-energy precision application modifications used currently with many center pivot systems to irrigate crops in the area.
SDI systems are efficient because they supply water directly to the root zones of plants, thereby minimizing evaporative and runoff losses from the soil surface. This is particularly important in arid and semiarid regions, where evaporation can result in significant water loss.
Although highly efficient, SDI use in this area of New Mexico is practically nonexistent.
The goal of this project is to educate producers in two areas:
— Installation and management strategies for subsurface drip irrigation;
—Applicability and benefits of utilizing information technologies (guidance systems) in conjunction with drip irrigation and in more traditional settings.
Historically, SDI has been utilized in production of high-value crops such as vegetables and alfalfa.
In the NMSU project, however, these technologies will be used together in a system for production of corn, sorghum and cotton, typical crops grown in eastern New Mexico, and will be compared with conventional systems of irrigation and management.
Drip tapes will be set on a typical row spacing (30-inch) and management will be representative of common practices in the area. Water use efficiencies will be estimated for all crops and crops will be evaluated for a best fit into the drip-GIS/GPS.
Differences in system inputs (e.g., water, fertilizers, herbicides) and outputs (e.g., yields, economic returns) will be documented throughout the duration of the project.
Mark Marsalis is agronomist at New Mexico State University’s Agricultural Science Center at Clovis. He can be reached at 985-2292 or by e-mail at: marsalis@nmsu.edu