80 years of the Dendropark “Olexandria” within the National Academy of Sciences of Ukraine: Conservation of rare plants in quasi-natural ecosystems of the Dendropark “Olexandria”

The results of the research on the conservation and restoration of the rare flora of the Dendropark “Olexandria” are presented across five research themes. In particular, the adaptive potential of introduced and native rare plants was assessed in the park’s quasi-natural ecosystems, which are coenotically associated with forest, meadow, meadow-steppe, riparian-aquatic, and aquatic plant communities. The prospects for establishing homeostatic introduced populations, clones, and ex situ biogroups of rare species have been demonstrated. According to the inventory, the rare plant component of the dendropark currently comprises 282 species and subspecies, both natural and cultivated. Of these, 92 species are included in the Red Book of Ukraine. In addition, 41 species are protected in the city of Kyiv and the Kyiv Region. 214 species are protected internationally; in particular, 8 species are listed in the appendices to the Bern Convention, and nine are protected under the CITES Convention. Almost 35 % (98 species) are preserved in the collection area “Rare Plants of the Flora of Ukraine”. In accordance with the concept of ex situ conservation of rare species, the reproductive potential and viability of native and introduced rare flora species were investigated. Monitoring was introduced for the area, abundance, and age structure of populations, clones, and biogroups of rare species in the forest, meadow, meadow-steppe, and riparian-aquatic ecosystems of the dendropark. The research provides substantial evidence that the most promising approach to ex situ conservation is the establishment of self-regenerating, stable populations, including introduced populations, which represent fragments of natural phytocoenoses and remain in continuous interaction with their components. Phenological observations identified a set of unfavorable climatic factors that limit the development of 79 introduced dendrosozophytes in the study region under ongoing climate change. Based on the findings, methodological recommendations were developed to optimize the conservation of rare plants in the Dendropark “Olexandria”.