FOR QUESTIONS ABOUT OF RELICT IN THE FLORA AND VEGETATION OF STEPPE ECOSYSTEMS OF THE BAIKAL SIBERIA
B.B. Namzalov
Buryat StateUuniversity, 670000, Ulan-Ude, Smolin str., 24a namsalov@bsu.ru
Keywords: steppe ecosystems, species, relict, fl orogenesis, adaptation, ecotone population, speciation, endemism
Abstract
Th e fl ora of steppes of the Baikal Siberia (BS) is rich enough (666 species of high vascular plants), that is a consequence
of features of a climate, orography, and also its buff er position between Northern and the Central Asia. In a variety of
steppe relicts BS are in some measure refl ected palaeogeographic events in open spaces of Northern Asia throughout
last 3-5 million years, from tertiary savannas and deserts to tundra-steppe landscapes of Pleistocene. Besides in an
exchange and transformation of fl ora the great value had as median position of territory BS in a trans-Asiatic
mountain belt, and climatic influence of Megaberingia, and also influence of glacial epoch, connected with
cryoaridisation. All it has formed a basis of high uniqueness of fl ora of steppes BS. It not only the most ancient relicts
of paleogen-neogen age (Peganum nigellastrum, Caryopteris mongolica, Craniospermum subvillosum), but also
pleistocene periglacial (Chamaerhodos altaica, Oxytropis eriocarpa, Patrinia sibirica, Gentiana decumbens, Artemisia
depauperata). Its perfect model for knowledge fl orogenesis not only in mountains of Siberia, but also the north of the
Central Asia.
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