Abstract
The article presents the results of ecological and biological analysis of species composition of five rare and endangered endemic plant species of southeastern Kazakhstan listed in the Red Book of the Republic of Kazakhstan. The importance of this research topic is determined by the need for a comprehensive and in-depth understanding of the ecological and biological characteristics of rare plant species growing in the southeast of Kazakhstan. The studies were conducted in the southeast of Kazakhstan (Zailiysky Alatau, Ketpen), where the objects of the study were representatives of rare and endangered endemic plant species: Astragalus rubtzovii Boriss, Taraxacum kok-saghyz L.E. Rodin., Schmalhausenia nidulans (Regel) Petr. Betula Jarmolenkoana Golosk., Rheum wittrockii Lundstr., from natural populations. The study of the state of the coenopopulation of rare and endemic plant species was carried out by route and semi-stationary methods. The novelty of the work is that for the first time the most complete ecological and biological characteristics of rare and endangered endemic plant species of the southeast of Kazakhstan are given, their biological features and habitat characteristics are studied. In the study area, 5 identified rare and endangered endemic plant species are represented by 2 types of life forms, where the predominant group among rare and endemic species is hemiocryptophytes (perennial plants) and one species is represented by a phanerophyte - a woody plant (Betula jarmolenkoana).