The Biodiversity of Exposure of Forest–Steppe Mountain Biomes of Siberia

The forest–steppe is considered as an integral geographical and ecological-phytocenotic zonal phenomenon of Northern Eurasia, which has its own characteristic features. The unique altitudinal zone of the forest–steppe is formed in the mountains of Siberia and occupies a certain place in the altitudinal-zonal spectra of the mountains. The structure of the oroboreal forest–steppe is considered on the basis of the ecosystem concept and an ecological–geographical approach to data interpretation. An exposed forest–steppe is a complex combination of plant communities of forests and steppes that occupy contrasting ecotopes within the same altitudinal level, forming a single indigenous altitudinal-climatic ecosystem, where its components closely interact with each other and with the surrounding natural conditions. The cenotic and biotic diversity of the forest–steppe is due to bioclimatic conditions that determine the hydrothermal areas of distribution of mountain formations and the composition of their climatypes. Characteristics of forest–steppe combinations of seven regional orobiomes of Siberia provide comparative information about the geography of mountain forest–steppe, the combination of forest and steppe communities, their composition and bioclimatic conditions of development.