¹⁵N tracer technology can be used to study the distribution of fertiliser N in the soil–plant system. However, few studies have used ¹⁵N tracer to directly label organic fertiliser such as livestock manure. Therefore, we analysed the distribution of N derived from cattle manure labelled with¹⁵N in winter wheat plants and the soil. An unlabelled large-plot experiment and ¹⁵N-labelled micro-plot experiment were performed using five fertilisation treatments: M (30 t ha^–1 manure) without additional N fertiliser, M+N75 (75 kg N ha^–1), M+N150 (150 kg N ha^–1), M+N225 (225 kg N ha^–1) and M+N300 (300 kg N ha^–1). The amounts of manure-derived N in crop plants and the soil were determined over a 2-year period (2019 and 2020). The wheat yield of M+N150 treatment plots was close to the highest wheat yield obtained in the M+N225 treatment plots (6311 kg ha^–1 in 2019 and 6523 kg ha^–1 in 2020). A large amount of manure-derived N was distributed in the whole plants treated with M+N150, being 78.4% (2019) and 58.3% (2020) higher than that in the plants treated with M+N300. The N use efficiency of manure in the M+N150 treatment plots was 8.1%, not unlike the highest N use efficiency observed in the M+N75 treatment plots (8.4%, sum of 2019 and 2020). The manure-derived total N at 0–40 cm soil depth in the M+N150 treatment plots was lower than that in the M treatment plots, whereas the manure-derived mineral N in the M+N150 treatment plots was similar to that in the M treatment plots and lower than that in the M+N300 treatment plots. These results suggested that the application of 30 t ha^–1 of cattle manure with 150 kg ha^–1 of N fertiliser was the optimal fertilisation treatment in the soil–wheat system, which could obtain high crop yield and improve N use efficiency by increasing the distribution of manure-derived N in whole plants and reducing manure-derived N in the soil.

¹⁵ N示踪技术可用于研究土壤-植物系统中肥料N的分布。然而，很少有研究使用¹⁵ N 示踪剂直接标记有机肥，如牲畜粪便。因此，我们分析了来自牛粪的氮在冬小麦植物和土壤中的分布情况，其中标有^{15 N。使用 5种}施肥处理进行^了未标记的大小区试验和¹⁵ N150 (150 kg N ha ^–1 )、M+N225 (225 kg N ha ^–1 ) 和 M+N300 (300 kg N ha ^–1）。在 2 年期间（2019 年和 2020 年）测定了作物和土壤中粪肥衍生 N 的含量。M+N150 处理地块的小麦产量接近 M+N225 处理地块的最高小麦产量（2019 年为 6311 kg ha ^-1和 6523 kg ha ^-12020 年）。M+N150 处理的整株植物中大量的粪源氮分布，分别比 M+N300 处理的植物高 78.4%（2019 年）和 58.3%（2020 年）。M+N150 处理地块的肥料氮利用效率为 8.1%，与 M+N75 处理地块中观察到的最高氮利用效率（8.4%，2019 年和 2020 年之和）没有什么不同。M+N150处理样地0~40 cm土层粪源总氮低于M处理样地，而M+N150处理样地粪源矿物N与M处理样地相似。 M 个处理小区，低于 M+N300 个处理小区。这些结果表明，施用 30 t ha ^-1的牛粪与 150 kg ha ^-1氮肥是土壤-小麦系统中的最佳施肥处理，通过增加粪源性氮在全株中的分布和减少土壤中的粪源性氮，可以获得作物高产和提高氮素利用效率。