Journal or Book Title
Nitrogen fixation by the Haber–Bosch process has more than doubled the amount of fixed N on Earth, significantly influencing the global N cycle. Much of this fixed N is made into N fertilizer that is used to produce nearly half of the world’s food. Too much of the N fertilizer pollutes air and water when it is lost from agroecosystems through volatilization, denitrification, leaching, and runoff. Most of the N fertilizer used in the United States is applied to corn (Zea mays L.), and the profitability and environmental footprint of corn production is directly tied to N fertilizer applications. Accurately predicting the amount of N needed by corn, however, has proven to be challenging because of the effects of rainfall, temperature, and interactions with soil properties on the N cycle. For this reason, improving N recommendations is critical for profitable corn production and for reducing N losses to the environment. The objectives of this paper were to review current methods for estimating N needs of corn by: (i) reviewing fundamental background information about how N recommendations are created; (ii) evaluating the performance, strengths, and limitations of systems and tools used for making N fertilizer recommendations; (iii) discussing how adaptive management principles and methods can improve recommendations; and (iv) providing a framework for improving N fertilizer rate recommendations.
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Morris, Thomas F.; Murrell, T. Scott; Beegle, Douglas B.; Camberato, James J.; Ferguson, Richard B.; Grove, John; Ketterings, Quirine; Kyveryga, Peter M.; Laboski, Carrie A. M.; McGrath, Joshua M.; Meisinger, John J.; Melkonian, Jeff; Moebius-Clune, Bianca N.; Nafziger, Emerson D.; Osmond, Deanna; Sawyer, John E.; Scharf, Peter C.; Smith, Walter; Spargo, John T.; van Es, Harold M.; and Yang, Haishun, "Strengths and Limitations of Nitrogen Rate Recommendations for Corn and Opportunities for Improvement" (2018). Agronomy Publications. 489.