[Determinacy and synchronicity of fallow succession in the Tuva steppes].

Succession on five fallows of Tuva has been studied. It has been shown that the fallow succession proceeds regularly and synchronously. Under the arid conditions of Tuva, weeds are developed at the initial stage of the succession (0-4 years). The first intermediate stage (4-7 years) on all fallows is characterized by the absolute predominance of weeds and the appearance of dominants typical for specific steppes. At the second intermediate stage (7-11 years), the species of aboriginal steppes dominate on all fallows. At the late stage (11-17 years), terminal communities with the combinations of species typical for each steppe, including predominant species, are developed.