Campbell Tracy, Ruark Matthew, Boswell Edward, Lowery Birl
Department of Soil Science, University of Wisconsin-Madison, Madison, Wisconsin, USA.
J Environ Qual. 2025 Mar-Apr;54(2):397-409. doi: 10.1002/jeq2.20672. Epub 2025 Jan 16.
Maintaining yield goals while reducing nitrate-nitrogen (NO-N) leaching to groundwater is a challenge for potato (Solanum tuberosum) production in the Wisconsin Central Sands as well as across the United States. The objectives of this study were to quantify the effect of conventional and enhanced efficiency nitrogen (N) fertilizers on NO-N leaching, crop yield, and N uptake in potatoes. We compared five N treatments, which include a 0 N control and 280 kg ha as ammonium sulfate and ammonium nitrate (AS/AN), polymer-coated urea (PCU), urea with a urease inhibitor (Urea+UI), or urea with a UI and a nitrification inhibitor (Urea+UI+NI). The study occurred on grower fields during the 2009, 2010, and 2011 growing seasons, and NO-N leaching was measured with equilibrium tension lysimeters. PCU resulted in a reduction in NO-N leaching and an increase in yield compared to AS/AN in a year with large early-season rainfall; Urea+UI also reduced NO-N leaching in this year. In 2010, large plot-to-plot variation and 250 kg ha of additional N applied by the grower masked our ability to see differences among fertilized treatments. In 2011, a year with less intense rainfall events, no differences among treatments were observed. Collectively, these results show a potential benefit to PCU, but these benefits are only realized under specific seasonal weather conditions. Overall, the percentage of applied N lost to leaching during the growing season and removed in biomass was relatively low, suggesting substantial amounts of NO-N leaching outside of the growing season.
在威斯康星州中部沙地以及美国各地的马铃薯（Solanum tuberosum）生产中，在维持产量目标的同时减少硝态氮（NO-N）向地下水的淋失是一项挑战。本研究的目的是量化传统氮肥和增效氮肥对马铃薯中NO-N淋失、作物产量和氮吸收的影响。我们比较了五种施氮处理，包括不施氮对照以及施280千克/公顷硫酸铵和硝酸铵（AS/AN）、聚合物包膜尿素（PCU）、添加脲酶抑制剂的尿素（Urea+UI）或添加脲酶抑制剂和硝化抑制剂的尿素（Urea+UI+NI）。该研究于2009年、2010年和2011年生长季在种植者的田块上进行，使用平衡张力渗压计测量NO-N淋失。在一个生长季早期降雨量大的年份，与AS/AN相比，PCU减少了NO-N淋失并提高了产量；Urea+UI在该年份也减少了NO-N淋失。2010年，种植者额外施用250千克/公顷氮肥导致的大的小区间差异掩盖了我们观察施肥处理间差异的能力。2011年，降雨事件强度较小，各处理间未观察到差异。总体而言，这些结果显示了PCU的潜在益处，但这些益处仅在特定的季节性天气条件下才能实现。总的来说，生长季中因淋失损失并在生物量中去除的施氮百分比相对较低，这表明在生长季之外有大量的NO-N淋失。
