Results of the Partial Least Squares Analysis.

Avg.R2 is the average amount of variability explained by the combinations of one to seven latent factors (LF1-7), Latent factors are formed by linear combinations of all dependent variables (i.e., species) (Y) and predictors (X); the weights of the latter on each of these factors are also quoted. Predictor codes are for three species of lichen (Hphy – Hypogymnia physodes, Psax – Parmelia saxatilis, Psul – P. sulcata) and one substrate category (bark – tree bark), that are the qualitative states of these two ordinary variables; note that Xanthoria parietina and rock are redundant in the codification and are thus not included in the analyses.