The ¹⁵N gas-flux method allows for the quantification of N₂ flux and tracing soil N transformations. An important requirement for this method is a homogeneous distribution of the ¹⁵N tracer added to soil. This is usually achieved through soil homogenization and admixture of the ¹⁵N tracer solution or multipoint injection of tracer solution to intact soil. Both methods may create artefacts. We aimed at comparing the N₂ flux determined by the gas-flux method using both tracer distribution approaches. Soil incubation experiments with silt loam soil using (i) intact soil cores injected with ¹⁵N label solution, (ii) homogenized soil with injected label solution, and (iii) homogenized soil with admixture of label solution were performed. Intact soil cores with injected ¹⁵N tracer solution show a larger variability of the results. Homogenized soil shows better agreement between repetitions, but significant differences in ¹⁵N enrichment measured in soil nitrate and in emitted gases were observed. For intact soil, the larger variability of measured values results rather from natural diversity of non-homogenized soil cores than from inhomogeneous label distribution. Generally, comparison of the results of intact cores and homogenized soil did not reveal statistically significant differences in N₂ flux determination. In both cases, a pronounced dominance of N₂ flux over N₂O flux was noted. It can be concluded that both methods showed close agreement, and homogenized soil is not necessarily characterized by more homogenous ¹⁵N label distribution.

中文翻译：

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在^15种N 2气体通量的方法来确定N个₂流量：不同示踪剂添加的比较接近

在¹⁵ Ñ气体通量方法允许定量Ñ ₂通量和追踪土壤氮的转换。该方法的重要要求是添加到土壤中的¹⁵ N示踪剂的均匀分布 。通常通过将土壤均质化并掺入¹⁵ N示踪剂溶液或将示踪剂溶液多点注入完整土壤中来实现。两种方法都可能产生伪像。我们旨在比较使用两种示踪剂分布方法通过气体通量法确定的N ₂通量。使用（i）注入¹⁵ N的完整土壤芯的粉壤土进行土壤培养实验 标记溶液，（ii）注入标记溶液的均质土壤，和（iii）标记溶液混合的均质土壤。注入¹⁵ N示踪剂溶液的完整土壤核心显示出较大的结果变异性。均质土壤在重复之间表现出更好的一致性，但是在土壤硝酸盐和排放气体中测得的¹⁵ N富集存在显着差异。对于完整的土壤，测量值的较大差异是由非均质土壤核的自然多样性引起的，而不是由不均一的标记分布引起的。通常，对完整岩心和均质土壤的结果进行比较并没有发现N _2的统计学差异通量测定。在两种情况下，都注意到N ₂通量相对于 N ₂ O通量具有明显的优势。可以得出结论，两种方法都显示出紧密的一致性，并且均质的土壤不一定具有更均一的¹⁵ N标记分布特征。