Fig. 5. Increase in SOC sequestration by forest production overyielding induced by tree species mixtures.

Values are indices of over-yielding due to tree species mixtures. Negative, zero, or positive values indicate that mixed forests performed worse, equally, or better on average than their respective mono-specific counterparts (i.e., the tree species that compose the mixture). All mixed forests are angiosperm-gymnosperm mixtures, excepted two cases (one angiosperm-angiosperm, one gymnosperm-gymnosperm, but of different tree species). The SOC pool considered is the whole soil profile (forest floor + topsoil). A linear regression was fitted (level of confidence of the error band = 0.95). Source data are provided as a Source Data files.