Giovannini Camilla, Garcia-Mina Josè M, Ciavatta Claudio, Marzadori Claudio
Department of Agroenvironmental Science and Technology, Alma Mater Studiorum University of Bologna, Bologna, Italy.
J Agric Food Chem. 2009 Jun 10;57(11):4883-7. doi: 10.1021/jf900264m.
The use of N-(n-butyl)thiophosphoric triamide (NBPT), as a urease inhibitor, is one of the most successful strategies utilized to increase the efficiency of urea-based fertilization. To date, NBPT has been added to the soil incorporated in fertilizers containing either urea or the inhibitor at a fixed percentage on the urea weight. The possibility of using NBPT physically separated from urea-based fertilizers could make its use more flexible. In particular, a granulated product containing NBPT could be utilized in soils treated with different urea-based fertilizers including livestock urine, the amount depending on soil characteristics and/or the urea source (e.g., mineral fertilizer, organo-mineral fertilizer, or animal slurry). In this study, a multilayer soil column device was used to investigate the influence of an experimental granular product (RV) containing NBPT and a garlic extract, combining the ability to protect NBPT by oxidation and nitrification inhibition activity, on (a) spatial variability of soil urease and nitrification activities and (b) timing of urea hydrolysis and mineral-N form accumulation (NO(2)(-), NO(3)(-), NH(4)(+)) in soil treated with urea. The results clearly demonstrated that RV can, effectively, inhibit the soil urease activity along the soil column profile up to 8-10 cm soil layer depth and that the inhibition power of RV was dependent on time and soil depth. However, nitrification activity is not significantly influenced by RV addition. In addition, the soil N transformations were clearly affected by RV; in fact, RV retarded urea hydrolysis and reduced the accumulation of NH(4)(+)-N and NO(2)(-)-N ions along the soil profile. The RV product was demonstrated to be an innovative additive able to modify some key ureic N trasformation processes correlated with the efficiency of the urea-based fertilization, in a soil column higher than 10 cm.
使用N-（正丁基）硫代磷酸三酰胺（NBPT）作为脲酶抑制剂，是提高尿素基施肥效率最成功的策略之一。迄今为止，NBPT已按尿素重量的固定百分比添加到含有尿素或该抑制剂的肥料中并混入土壤。将NBPT与尿素基肥料物理分离使用的可能性会使其使用更加灵活。特别是，一种含有NBPT的颗粒产品可用于用不同尿素基肥料处理的土壤，包括牲畜尿液，用量取决于土壤特性和/或尿素来源（例如，矿物肥料、有机矿物肥料或动物粪便）。在本研究中，使用多层土柱装置来研究一种含有NBPT和大蒜提取物的实验性颗粒产品（RV）的影响，该产品兼具通过氧化保护NBPT的能力和硝化抑制活性，对（a）土壤脲酶和硝化活性的空间变异性，以及（b）用尿素处理的土壤中尿素水解的时间和矿质氮形态积累（NO₂⁻、NO₃⁻、NH₄⁺）的影响。结果清楚地表明，RV能够有效地抑制沿土柱剖面直至8 - 10厘米土层深度的土壤脲酶活性，并且RV的抑制能力取决于时间和土壤深度。然而，添加RV对硝化活性没有显著影响。此外，土壤氮转化明显受到RV的影响；事实上，RV延缓了尿素水解，并减少了沿土壤剖面NH₄⁺-N和NO₂⁻-N离子的积累。在高于10厘米的土柱中，RV产品被证明是一种创新添加剂，能够改变一些与尿素基施肥效率相关的关键尿素氮转化过程。
