Epiphytic lichen diversity in Estonian and Fennoscandian old coniferous forests
Lichen species richness and species composition were compared between Estonian and Fennoscandian old coniferous forests, with a special emphasis on woodland key habitat indicator species. Altogether 42 Picea abies and 40 Pinus sylvestris sample plots were studied in Estonia, Finland, Sweden and Norway. In every plot lichens were recorded on five randomly selected trees; in addition, tree age and canopy openness by the sampled trees were measured. The results revealed clear differences in lichen species composition; the occurrence of many species differed between Estonia and Fennoscandia. Several indicator species were recorded only in one or two sample plots; the relatively frequent indicators differed between the two studied areas. The number of lichen species per sample plot was significantly higher in Fennoscandia compared to Estonia. Maximum tree age was positively correlated with species richness in Estonian spruce sample plots, and mean canopy openness with species richness in Estonian pine sample plots.