Figure 4.
(A) Tree species composition and (C) tree species richness effects on richness of EcM fungi. (B) Tree species composition and (D) tree species richness effects on evenness of EcM fungi. EcM fungal richness estimation is based on standardized residuals. Data represent the means of all samples with SEs. Different letters denote significant differences (p < 0.05) among factor levels. B, birch; P, pine; S, spruce; BP, birch-pine; BS, birch-spruce; PS, pine-spruce; BPS, birch-pine-spruce; 1, monospecific; 2, two-species mixtures; and 3, three-species mixture.