TUNDROSTEPA PHENOMENON IN THE BIOTA ОF XYLOTROPHIC FUNGI ОF SIBERIA

On the example of Betula-xylomycocomplex high-rise and zone regularities of numerical distribution the aphyllophoroid fungi in the territory of Transbaikalia are considered. The structure of domination in cenocomplexes of fungi at the heights from 650 (steppe) to 2 000 m above sea level (the upper bound of forest vegetation) is analysed. Similarity of the revealed regularities of high-rise and zone structure of a Betula-complex of Transbaikalia and the width and zone structure of a Betula-complex of fungi studied earlier in the territory of Western Siberia is shown. In particular, the increase in a role of stem parasites in extreme for development of forest vegetation of tundra and steppe part of both regions is noted. Pyrogenic character of Betula-complexes in their forest-steppe part is noted. Their differences determined, first of all, by features of climate are established. The greatest levels of similarity of a Betula-complex of Transbaikalia to a reference width and zone number of Betula-complexes of Western Siberia are noted in foresttundra and forest-steppe part of a range at the same time. It shows the known phenomenon of a transbaikal tundrostepa caused special droughty frigid climate of the region