DYNAMICS OF THE VITALITY OF CENOPOPULATIONS OF HOLOSTEUM GLUTINOSUM (M. BIEB.) FISCH. & C.A. MEY. (CARYOPHYLLACEAE) IN THE ECOTONE SYSTEM “WATER-LAND” OF THE COAST OF THE CHOGRAI RESERVOIR

Background. The assessment of the structure of cenopopulations of early spring juveniles can be used during the organization of biological monitoring at the population level. Such information is also applicable in assessing the situation in coastal ecosystems, for forecasting and reducing the risk of their violations. Purpose. Analysis of the viability of Holosteum glutinosum cenopopulations to characterize their stability in plant communities of the “water-land” ecotone system of the coast of the Chograi reservoir. Materials and methods. The studies were carried out in the growing seasons of 2018, 2019 and 2021 in five coenopopulations of H. glutinosum growing in plant communities located in the structural blocks of the ecotone. The vital spectrum of populations was obtained by the method of Yu.A. Zlobin [3, 10, 18], the vital type - using the Q criterion [3], the vitality of populations – based on the analysis of the vital index IVC [3], the degree of prosperity or depression of populations - the IQ index [4]. Results. During the four-year study period, in 5 populations of H. glutinosum, regardless of their localization in the ecotone, the value of the Q index exceeds the frequency of individuals of the lowest class of vitality, therefore they are classified as the “thriving” vital type. The value of the vitality indices for the entire period of the study is greatest in the cenopopulation No. 1, located in the fluctuation block. The first peak of the increase in vitality occurred at coenopopulation No. 1 in the fluctuation, the second – at coenopopulation No. 4 in the marginal ecotone blocks. Conclusion. The coenopopulations of H. glutinosum in the ecotone had a vital type of “thriving”. Analysis of the dynamics of vitality in the coenopopulations of H. glutinosum revealed that the conditions prevailing in the communities of fluctuation and marginal ecotone blocks provide the greatest vitality of populations No. 1 and No. 4.