Fig. 3
From: High adaptability of Pinus sylvestris var. mongolica to drought-induced soil nutrient deficiency
Effect of drought on soil water content, NH4+-N, NO3−-N, inorganic N, Olsen-P concentrations and available N:P ratio (mean ± SE, n = 3) in different soil depths. Different uppercase letters above the bars indicate significant differences between soil layers at each drought treatment, and different lowercase letters above the bars indicate significant differences among three drought treatments at each soil depth