Author
Delgado, Jorge | |
Duke, Harold |
Submitted to: International Conference on Precision Agriculture Abstracts & Proceedings
Publication Type: Proceedings Publication Acceptance Date: 7/5/2000 Publication Date: 3/6/2001 Citation: Delgado, J.A., Duke, H.R. 2001. Potential use of precision farming to improve nutrient management on an irrigated potato-barley rotation. International Conference on Precision Agriculture Abstracts & Proceedings. CD-ROM. Interpretive Summary: Since NO3- -N is a readily mobile form of N that can leach out of the root zone due to rain and or irrigation events, it is important that we use Best Management Practices (BMPs) that maximize N use efficiency (NUE). Since we can not evaluate every possible combination of BMPs and commercial field scenarios, computer model simulations offer a potential solution to evaluate the effects of these BMPs under commercial operations. The data needed for conducting these evaluations was collected on 38 commercial fields across South Central Colorado and was used to evaluate the effects of management on the N dynamics. Our NLEAP simulations of these N budgets show that for this region, when the recommended BMPs are applied in commercial operations, the system can potentially be in balance if small grains are rotated with vegetables. These simulations suggest that BMPs for this region can save up to 2.27 million dollars in N cycling and recovery a year. This is one of the few simulation manuscripts that have been conducted on a similar soil depth for shallow and deeper rooted crops to evaluate the N budgets and NO3- -N dynamics of inputs and outputs into the system. This was possible with the new NLEAP 1.20 version. Technical Abstract: Since NO3- -N is a readily mobile form of N that can leach out of the root zone due to rain and or irrigation events, it is important that we use Best Management Practices (BMPs) that maximize N use efficiency (NUE). Since we can not evaluate every possible combination of BMPs and commercial field scenarios, computer model simulations offer a potential solution to evaluate the effects of these BMPs under commercial operations. The data needed for conducting these evaluations was collected on 38 commercial fields across South Central Colorado and was used to evaluate the effects of management on the N dynamics and NUE, N losses, budgets, and balance between the NO3- -N that is leaving the rooting zone and the NO3- -N that is being pumped back with the irrigation water. NUE, NO3- -N leaching and N mining was significantly correlated with root depth. When small grains such as winter cover rye, winter wheat and barley are included in a rotation with lettuce and potato, the systems NUE is significantly increased. Additionally, with the inclusion and rotation of vegetables with small grains the system becomes more tied and closed and reduces the NO3- -N leaching losses increasing the potential to recover NO3- -N from the underground water. With the adequate implementation of BMPs and the use of crop rotations these small grain and cover crop systems will contribute to the mining of NO3- -N from the underground aquifer, protecting environmental quality and increasing the NUE of the agroecosystems in this region. |