Extended Data Fig. 8: Environmental variables and multicollinearity analysis.
From: Root microbiota assembly and adaptive differentiation among European Arabidopsis populations
a, Heatmap showing variation in 18 environmental variables measured across the 17 European sites. Values for each environmental property were normalized and the scale was adjusted to 1. 0 = lowest value measured value across sites, 1 = highest value measured value across sites). b, Heatmap depicting collinearity between the 18 environmental variables. Significant correlations detected between variables were assessed using Spearman´s rank correlation and variables showing correlation rs > 0.7 and rs < -0.7 (n = 17, P < 0.01) were considered as collinear. Two unique variables (Manganese, Copper) and five groups of collinear variables (group K, group P, group Boron, group NO3, group pH) were defined and used for PERMANOVA analyses.
