Figure captions
Figure 1: Sampling Design. Overview of the BEF-China
experimental Site A (panel A) with the two sampled plots (green)
representing two-species mixture plots. Plot tree planting grid pattern
with a marked tree pair, here only a small section of the 20x20 trees
plot was drawn. Positions of the five soil cores between the tree pair
with the in-core division of the depths. Tree species combinations are
shown in panel B.
Figure 2: Distance to tree and depth effects on microbial
biomass (top) and respiration (bottom) in monospecific tree pairs.Effects are predicted from the model (soil properties
~ depth * distance to tree ) with plot as random effect.
Distance to tree reports the distance to the closest tree from
monospecific tree pairs. Microbial biomass coloured blue (low) to red
(high), microbial respiration coloured purple (low) to orange (high).
The significance levels were standardised across the panels
(p<0.05: *, p<0.01: **, p<0.001:
*** ).
Figure 3: Distance to tree and depth effects on microbial
biomass (top) and respiration (bottom) overyielding in heterospecific
tree pairs. The mean value (grey square) of overyielding for microbial
biomass (A) and respiration (D) across all depths and positions, for
each depth (microbial biomass: B, yellow circle for 0-5 cm; brown
triangle for 5-10 cm, and microbial respiration: E, light blue circle
for 0-5 cm; dark blue triangle for 5-10 cm), and for each sampling point
by depth (microbial biomass: C and respiration: F). Confidence intervals
were predicted from models using the “ggpredict” function of the R
package ggeffects . The significance levels were standardised
across the panels (p<0.05: *, p<0.01: **,
p<0.001: *** ).