Kravchuk L. Comprehensive population analysis of species of medicinal plants of phytocenoses of Shostka geobotanical district

The dissertation presents the results of complex population analysis of five model species of medicinal plants, which are typical for Shostka geobotanical region (Convallaria majalis L., Helichrysum arenarium L., Hypericum perforatum L., Plantago major L., Thymus serpyllum L. emend. Mill.). Additionally, two populations of Thymus x polessicus were identified during the research. According to the indicators of population density, the studied plants are divided into three groups: 1) species in which the average values of the trait usually do not exceed 10 plants/m2 – Hypericum perforatum; 2) species in which the average values of the trait usually do not exceed 50 plants/m2 – Plantago major, Convallaria majalis, Helichrysum arenarium; 3) in which the average values of the trait usually exceed 50 plants/m2 – Thymus serpyllum, Thymus x polessicus. It is shown that the ontogenetic spectra of populations of all studied medicinal plants are incomplete. For each of the populations the sizes are determined and morphostructural models of their plants are developed. The shows that the functioning of medicinal plants populations is accompanied by the formation of morpho-adaptations, is directly related to the manifestation of morphological variability (intrapopulation variation of morphoparameters absolute values) and plasticity (interpopulation variation of morphoparameters values). It is shown that the peculiarities of the dimensional structure of populations are manifested due to differences in the distribution of plants by dimensional classes and by combinations of different pairs of classes. On the basis of classical approaches, it has been established that a set of key (determining the level of vitality) indicators are formed only by static metric morphoparameters. Most of the studied medicinal plants (except for Hypericum perforatum and Thymus x polessicus) represent all three qualitative types of populations (depressed, balanced and prosperous). A statistically significant effect on morphological features and population characteristics of medicinal plants of a number of ecological and coenotic factors has been proved. According to the results of a comprehensive assessment of the ontogenetic and vitality structure, populations of medicinal plants were differentiated into groups according to the level of their ability to function sustainably. The technique based on the use of three original indices (vitality-restorative (IQV), vitality-generative (IQG) and integrative (IQVG)) was tested.