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<p>The <span class="inline-formula">¹⁵N</span> gas-flux method allows for the quantification of <span class="inline-formula">N₂</span> flux and tracing soil N transformations. An important requirement for this method is a homogeneous distribution of the <span class="inline-formula">¹⁵N</span> tracer added to soil. This is usually achieved through soil homogenization and admixture of the <span class="inline-formula">¹⁵N</span> tracer solution or multipoint injection of tracer solution to intact soil. Both methods may create artefacts. We aimed at comparing the <span class="inline-formula">N₂</span> 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 <span class="inline-formula">¹⁵N</span> 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 <span class="inline-formula">¹⁵N</span> tracer solution show a larger variability of the results. Homogenized soil shows better agreement between repetitions, but significant differences in <span class="inline-formula">¹⁵N</span> 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 <span class="inline-formula">N₂</span> flux determination. In both cases, a pronounced dominance of <span class="inline-formula">N₂</span> flux over <span class="inline-formula">N₂</span>O flux was noted. It can be concluded that both methods showed close agreement, and homogenized soil is not necessarily characterized by more homogenous <span class="inline-formula">¹⁵N</span> label distribution.</p>