A field experiment was conducted in years 2016-2018 in crop-rotation: faba bean-winter wheat-winter wheat. After seedling emergency (2016) mineral fertilizer (¹⁵NH₄)₂SO₄ having 20.1 at% ¹⁵N (dose of 30 kg N ha⁻¹) was applied. The faba bean biomass contained 194.1 kg ha⁻¹of nitrogen (140.0 kg of N in seeds and 54.1 kg in crop residue). In this amount including 58.7 kg N ha⁻¹ in seed and 21.2 kg of N from air. Crop residue were ploughed into soil. Plots with winter wheat cultivated after faba bean (2017) were divided on two sub-plots 0 and 100 kg N ha⁻¹. Overall, winter wheat cultivated for two subsequent years took up from total nitrogen of crop residue 16.1 kg ha⁻¹ of N from control and 29.8 kg ha⁻¹ fertilized objects, but from biologically fixed nitrogen 6.29 and 11.6 kg ha⁻¹, respectively. Applied fertilizer contained 5.920 kg ¹⁵N ha⁻¹ from which 1.577 kg ¹⁵N ha⁻¹ was cumulated in faba bean seeds, 0.662 kg ¹⁵N ha⁻¹ in crop residue (sum 2.239 kg ¹⁵N ha⁻¹), 0.195 kg ¹⁵N ha⁻¹ and in winter wheat harvested (2017) and 0.084 kg ¹⁵N ha⁻¹ in winter wheat harvested (2018).

在2016-2018年间对轮作进行了田间试验：蚕豆-冬小麦-冬小麦。在紧急苗期结束后（2016年），施用了具有20.1 at％¹⁵ N（30 kg N ha ^-1的剂量）的矿物肥料（¹⁵ NH ₄）₂ SO ₄。蚕豆生物量含有194.1 kg ha ^-1的氮（种子中140.0 kg的氮和作物残渣的54.1 kg）。该量包括种子中的58.7 kg N ha ^-1和来自空气的21.2 kgN。将农作物残余物耕种到土壤中。将蚕豆（2017）之后种植的冬小麦的地块分为0和100 kg N ha ^-1两个子图。总体而言，随后两年种植的冬小麦吸收了对照和29.8 kg ha ^-1受精物体中作物残渣的总氮16.1 kg ha ^-1，而生物固定氮分别吸收了6.29和11.6 kg ha ^-1。施用的肥料包含5.920千克¹⁵ N ha ^-1，其中1.577千克¹⁵ N ha ^-1累积于蚕豆种子中，农作物残渣中累积0.662千克¹⁵ N ha ^-1（总和为2.239千克¹⁵ N ha ^-1），0.195千克¹⁵ N ha ^-1和收获的冬小麦（2017）和0.084公斤¹⁵收获的冬小麦的N ha ^-1（2018）。