The frequency and timing of nitrogen (N) application on corn strongly influences environmental N losses and yield, particularly in different weather. Split N application is a 4R (Right Source, Right Rate, Right Time, Right Place) nutrient management practice that ensures sufficient N supply when the crop needs it most, minimizing N losses to the environment, while allowing N rate adaptations as the season evolves. The purpose of this study is to investigate the agronomic, environmental, and economic performance of split N application on corn compared to traditional pre-plant broadcast methods under alternative timings, weather scenarios and N rates at Elora, Ontario, using biophysical and economic simulation models. The modelled results show that split N application with rate adjustments may increase profit between 14.6% and 19.5% in dry conditions and between 1.4% and 15.7% in wet conditions, while lowering environmental NO₃- leaching, N₂O emissions and NH₃ volatilization losses in most weather. However, only in dry weather does the profit maximizing split N application strategy maximize environmental benefits, giving rise to the potential for government policy to address this trade-off between economic pursuits and environmental goals.

对玉米施氮 (N) 的频率和时间对环境氮损失和产量有很大影响，尤其是在不同天气下。分批施氮是一种 4R（正确的来源、正确的施肥量、正确的时间、正确的地点）养分管理实践，可确保在作物最需要的时候有足够的氮供应，最大限度地减少对环境的氮损失，同时允许随着季节的变化进行施氮量调整. 本研究的目的是使用生物物理和经济模拟模型，在安大略省埃洛拉 (Elora) 的替代时间、天气情景和施氮率下，与传统的种植前播撒方法相比，研究在玉米上施氮肥的农艺、环境和经济性能。 . 建模结果表明，带有费率调整的拆分 N 应用程序可以将利润增加 14.6% 到 19%。₃ -大多数天气下的浸出、N ₂ O 排放和NH ₃挥发损失。然而，只有在干燥天气下，利润最大化分裂 N 应用策略才能使环境效益最大化，从而产生政府政策解决经济追求和环境目标之间这种权衡的潜力。