Structure of some rare flora species populations in conditions of Volhynian Upland
Abstract
I.P. Lohvynenko*, S.M. Lyko, I.M. Trochymchuk, O.I. Portukhay and S.O. Glinska
At the present stage, the study of rare and endangered plant species and the preservation of natural biodiversity is one of the most pressing problems. The purpose of this work was monitoring research of the spatial and ontogenetic structure of the populations of some rare flora species of the Volhynian Upland (Adonis vernalis, Galanthus nivalis, Carlina onopordifolia, Cypripedium calceolus, Epipactis palustris, Cladium mariscus, Saxifraga granulata) and the determination of causes that adversely affect the condition of their populations. The isolation of age spectra and the study of the spatial structure of populations of rare flora species were conducted taking into account the methods of V. Grant, K.A. Malynovskyi, T.O. Rabotnov, O.O. Uranov, O.V. Smyrnova and others. Categories of ontogenetic spectra were determined in accordance with the recommendations of Yu. A. Zlobin. In the conditions of the Volhynian Upland, the population of A. vernalis is comprehensive, normal, with a left-sided ontogenetic spectrum, however – regressive.The firmness and structure of species populations depend on the dynamics of the development of natural phytocoenoses. The parameters of the G. nivalis cenopopulation somewhat vary depending on the ecological-cenotic conditions of growth, as well as the location within the range and characterized by homeostaticity, centered age spectrum and average density. Populations of the species C. onopordifolia are isolated from each other, so they are very fragmented. By their structure, they are comprehensive, right-sided, but regressive. The structure of the populations of C. calceolus depends on the anthropic effect on the growth site. Homeostatic populations with full age age spectra are presented in antropically not disturbed places. Most species of the species have a right-side ontogenetic spectrum and show a complete and stable dynamics of the species. Monitoring research on the condition of E. palustris populations show stable positions of the species in phytocoenoses.The state of the populations of E. palustris depends mainly on the species biology and slightly less on the influence of meteorological conditions. Perennial observations of the species indicate a significant prevalence of generative individuals in populations. Studies of C. mariscus populations indicate their high density and number. It is the high density of underwater evergreen perennial stems C. mariscus and abundant fruiting, which ensure the stability of species populations, and also form a natural barrier against the penetration of other species.The populations of S. granulata are confined to the forest edge ecotones. Growing in the ecotone between forest or shrub and meadow vegetation in the valleys of the rivers, they form linear populations, which include a small number of individuals. Studies in the territory of Ukraine show that S. granulata as a species disappears. Consequently, most of the investigated populations of rare and endangered flora species are degraded.