Ontogenetic Structure of Rare Plant Species on the Usturt Plateau in Uzbekistan.

The article assesses the state of the ontogenetic structure of some rare species (Rosa laxa Retz., Crataegus korolkowii L. Henry, Artemisia terrae-albae Krasch. and Salsola arbusculiformis Drob.) growing on the Karakalpak part of Ustyurt. The study shows that the studied cenopopulations are normal and mostly incomplete under the ecological and cenotic conditions of Ustyurt. The ontogenetic spectra of specific cenopopulations are left-sided and centered, which associated with the environmental living conditions and fluctuations in weather conditions. The similarity of biological features (long-term life expectancy of individuals in a middle-age ontogenetic state, the least elimination, and difficult seed germination) in individuals of different species and the actual, ontogenetic spectra with a characteristic spectrum indicates a stable state of the studied cenopopulations on the Karakalpak part of Ustyurt. [ABSTRACT FROM AUTHOR]