Extended Data Fig. 2: Effects of long-term N and P fertilization on soil organic matter, amino sugars, and microbial necromass contents.
From: Soil carbon sequestration enhanced by long-term nitrogen and phosphorus fertilization
a, Soil organic matter. b, Muramic acid (MurN). c, Galactosamine (GalN). d, Glucosamine (GluN). e, Bacterial necromass C. f, Fungal necromass C. g, The ratio of bacterial to fungal necromass C. Box plots represent first and third quartiles (box), medians (central horizontal line), largest value smaller than 1.5 times the interquartile range (upper vertical line) and smallest value larger than 1.5 times the interquartile range (lower vertical line). Different letters above boxes indicate statistically significant differences among treatments (n = 4), determined using one-way ANOVA followed by Tukey’s post hoc test (two-sided; p < 0.05). Nil, no fertilization; P, P-only fertilization; N, N-only fertilization; NP, combined fertilization with N and P.
