Table C1. Spearman rank correlation coefficients for correlations of nonextrapolated
50 and 95% rooting depths (D_{50} and D_{95})
with environmental variables (see Table 3 in the paper for definitions of variables).








All temperate and boreal (n = 335; organic
layer: n = 315)


















Temperate and boreal forests (n = 149; organic
layer: n = 132)


















Temperate and boreal grass and shrublands & savannas
(n = 186; organic layer: n = 183)


















All tropical (n = 135; organic layer: n
= 130)


















Tropical forests (n = 86; organic layer: n
= 82)


















Tropical grass and shrublands and savannas (n
= 49)


















Notes: Coefficients marked in boldface are statistically significant at P < 0.01; those marked in bold italics are significant at P < 0.05. Significance levels were not adjusted for multiple comparisons.
Table C2. Spearman rank correlation coefficients for correlations of rooting depths with environmental variables (see Table 3 in paper for definitions of variables).








Nonextrapolated profiles (n = 96; organic layer:
n = 94)


















Extrapolated profiles (n = 374; organic layer:
n = 351)


















Notes: Listed are the coefficients for nonextrapolated 50 and 95% rooting depths (D_{50} and D_{95}) of profiles sampled to the maximum rooting depth or to at least 2 m depth and the coefficients for extrapolated 50 and 95% rooting depths (D_{x50} and D_{x95}) profiles sampled to less than 2 m depth. Coefficients marked in boldface are statistically significant at P < 0.01; those marked in bold italics are significant at P < 0.05. Significance levels were not adjusted for multiple comparisons.