Fig. 2
From: Trajectories in nitrogen availability during forest secondary succession: illustrated by foliar δ15N
Distribution of 16 forest secondary successions in this study, including 4 boreal forests (2 sites by continuous observation and 2 sites by “space-for-time” substitutions), 4 temperate forests (by “space-for-time” substitutions), and 8 tropical forests (by “space-for-time” substitutions). Detailed information on these sites is available in Additional file 1: Table S1.