Horticultural Sciences Department, University of Florida, 1253 Fifield Hall, 2550 Hull Road, PO Box 110690, Gainesville, FL, 32611, USA.
Soil and Water Sciences Department, University of Florida, Gainesville, FL, 32611, USA.
Sci Rep. 2020 Dec 10;10(1):21754. doi: 10.1038/s41598-020-78198-1.
Elevated levels of nitrous oxide (NO) emissions are a matter of concern in agricultural soils especially when flooding (hypoxic conditions) results from over irrigation or frequent rains. This study is the first to report the use of two solid oxygen fertilizers (SOFs, calcium peroxide and magnesium peroxide) to reduce NO production in mineral and organic soils amended with N fertilizer in a short-term laboratory incubation besides two biochars. In general, organic soil had greater NO production than mineral soil. Soils amended with nitrogen fertilizer exhibited increased NO production, by 74 times in mineral soil and 2 times in organic soil. Both solid oxygen fertilizers in mineral soil (98-99%) and calcium peroxide in organic soil (25%) successfully reduced NO production than corresponding N fertilized treatments. Additionally, a greater level of available nitrate-N (52-57 and 225 mg kg in mineral and organic soil, respectively) was recorded with the solid oxygen fertilizers. Corn residue biochar with N fertilizer increased NO production in mineral soil but decreased in organic soil, while pine bark biochar with N did not affect the NO production in either soil. Depending on soil, appropriate SOFs applied were able to reduce NO production and maintain greater nitrate-N levels in flooded soil. Thus, solid oxygen fertilizers can potentially be used as an effective way to reduce NO emission from hypoxic soil in agricultural production systems.
氧化亚氮（NO）排放水平升高是农业土壤中的一个问题，特别是在过度灌溉或频繁降雨导致缺氧（缺氧条件）的情况下。本研究首次报道了在短期实验室培养中使用两种固体氧肥料（过氧化钙和过氧化镁）来减少矿物和有机土壤中氮肥料添加物的 NO 产生，此外还使用了两种生物炭。一般来说，有机土壤的 NO 产生量大于矿物土壤。添加氮肥料的土壤会增加 NO 的产生，在矿物土壤中增加了 74 倍，在有机土壤中增加了 2 倍。在矿物土壤中，两种固体氧肥料（98-99%）和在有机土壤中的过氧化钙（25%）都成功地减少了与相应的氮施肥处理相比的 NO 产生。此外，在矿物和有机土壤中分别记录到了更高水平的有效硝酸盐-N（分别为 52-57 和 225mgkg）。含氮肥料的玉米残渣生物炭增加了矿物土壤中的 NO 产生，但在有机土壤中减少了，而含氮的松树皮生物炭对两种土壤中的 NO 产生都没有影响。根据土壤的不同，适当施用的固体氧肥料能够减少缺氧土壤中的 NO 产生，并维持更高的硝酸盐-N 水平。因此，固体氧肥料可能是减少农业生产系统中缺氧土壤中 NO 排放的一种有效方法。
