Factors important for epiphytic lichen communities in wooded meadows of Estonia
The epiphytic lichen communities in open and overgrown wooded meadows in Estonia were examined. From 29 study stands, 179 taxa of lichens, lichenicolous and allied fungi were identified, 41 of them are nationally rare, red-listed or protected. Non-metric multidimensional scaling (NMS) was performed to examine the main gradients in species composition and to relate these gradients to environmental variables. The response of lichen species richness to the influence of the environmental variables was tested using a general linear mixed model (GLMM). We revealed that overgrowing of wooded meadows caused significant changes in lichen communities on trees: richness of lichen species decreased and the composition of species changed. Photophilous lichen communities with many species of macrolichens in open wooded meadows were replaced with associations of more shade-tolerant microlichen species. The composition of epiphytic lichen communities were also influenced by the tree species composition, diameter of trees and the geographical location of the stand.