The composition and structure of larch lichen communities in watershed light forests of the West Siberian plain

The structure of the lichen groups of Larix was investigated in the watershed larch light forests on the adjacent to the Polar Ural West Siberian plain territory. The composition of the lichen groups, the species diversity, the frequency and the projective coverage of the epiphytic lichen species were de-termined. The research was conducted on sample plots of 5x20 cm size located at the base of the tree, about 1.3 m up from the ground on the side with the most pronounced epiphytic cover. Ten larch trees were selected from 12 sample areas, each area 50x50 m size. Our research found out 50 different species of lichens belonging to 10 families and 30 kinds. The sample plots contained about 7 species at the tree base on average, with 19 spe-cies per the sampling area. Fruticose lichens pre-vailed (38 %) by the number of species. Five lichen species from Parmeliopsis, Biatora, Vulpicida, Tuckermannopsis genera were the most wide-spread. The common projective cover was 45 % on average. Crustose (50 % average of the overall cover) lichens were predominant. Biatora helvola, Parmeliopsis ambigua, P. hyperopta, Vulpicida pinastri had the highest percent of cover. The sam-ple plots contained about 4 species at the height of 1.3 m on average, with 10 species per the sampling area. Crustose lichens prevailed (54 %) by the number of species. Melanelia olivacea and Lecanora hagenii were the most widespread. The common projective cover was 30 % on average. Foliose lichens were predominant (69 %). Melanelia olivacea, Biatora helvola and Lecanora hagenii had the overall dominance.