marginally non-significantP = 0.098
Net nitrification also responded significantly to N addition but only in the biocrusts (increasing from 1.27 to 2.12 to 2.04 μg N g -1 d -1 , respectively, Table 2 ; Supplementary Table S2 ; Figure 2B ), although the Nitrification × Depth interaction was marginally non-significant ( P = 0.098).