ONTOGENETIC STRUCTURE OF TRIFOLIUM MONTANUM L. АND STIPA CAPILLATA L. POPULATIONS IN THE NATURE RESERVE “MYKHAILIVSKA TSILYNA”

Abstract

The article provides an assessment of the ontogenetic structure of the populations of Trifolium montanum L. and Stipa capillata L. of the Nature Reserve “Mykhailivska Tsilyna”. The relevance and importance of population studies for the protection and preservation of meadow-steppe plant species are substantiated. The territory of the Nature Reserve “Mykhailivska Tsilyna” and its vegetation are characterized. The method of establishing the ontogenetic structure of the studied species is described. The study covered three populations of Trifolium montanum L. and three populations of Stipa capillata L., which were growing on the territory of the Nature Reserve “Mykhailivska Tsilyna” as part of different plant groups. It is noted that there are differences between the mode of use and the threats to the populations of the species under study. It was found that populations of Trifolium montanum L. in the conditions of the phytocenoses of the Nature Reserve “Mykhailivska Tsilyna” are characterized by the incompleteness of the ontogenetic spectra and their centrality. Incomplete ontogenetics in all studied populations is primarily associated with the absence of seedlings and virgin plants. In the composition of some populations, immature and postgenerative individuals were also absent. High age indices were noted in all populations of the species, which indicates the predominance of degradation processes. This is especially characteristic of the population that grew in the new territory of the reserve, where haying does not take place. All studied populations of Stipa capillata L., as in the case of Trifolium montanum L., are characterized by incomplete ontogenetic spectra. Seedlings and senile plants are absent in all three studied populations. Only one population is characterized by the presence of subsenile plants and the absence of juvenile plants, which is not characteristic of the other two populations of Stipa capillata L. According to the sign of symmetry, the ontogenetic spectra of the two populations located in the new territory are centered, and the one growing in the historical territory is left-sided. Among the studied populations, one has the lowest age indices and grows on the historical territory as part of a rare plant group. The conducted analysis proved that the ontogenetic structure of the populations of the species Trifolium montanum L. and Stipa capillata L. in the territory of Nature Reserve “Mykhailivska Tsilyna” has a number of common and distinctive features. The dependence of the formation of the ontogenetic structure of populations is monitored not only on the edaphic conditions and regime of the territory, but also on the phytocenotic environment of the populations.