ДИНАМІКА ВІКОВОЇ СТРУКТУРИ ПОПУЛЯЦІЇ CROCUS HEUFFELIANUS HERB. У ПРИРОДНОМУ ЗАПОВІДНИКУ "МЕДОБОРИ" ЗА ОСТАННЄ ДЕСЯТИРІЧЧЯ

Abstract

Based on the long-term observations of Crocus heuffelianus Herb., the Red Book species of "Medobory" Nature Reserve, growing on the boundary of the area, the dynamics of the population age structure has been analysed. The study of the population and phenology has been conducted since 1995 at the Botanical Experimental Area (BP-2), which is located in Viknianske forestry (square 32, board 7) and covers an area of 0.1925 hectares.The number and density of the cenopopulation have been studied. The ratio of the number of individuals to the area of the population is taken for the density, and the number of individuals in its entire area – for the absolute number. The number of species ranged from 347 to 753 individuals. The average plant density is 0.27 individuals per square meter. The highest index was in the years 2016 and 2018 – 0.39 and 0.38 individuals per square meter, and the lowest was in 2005 – 0.09 individuals per square meter.During the investigating over the past decade, surveys of plants of different ages (juvenile, virgin and generative), as well as phenological observations were conducted. Allocation of age groups was carried out in accordance with the classification of Melnyk V.I.The population of Crocus heuffelianus Herb in the Reserve is established as a full-fledged and left-handed. Only in 2011 it was intermediate.According to the results of phenological observations, the average long-term date of the vegetation onset is the 15th of March, the beginning of flowering – the 24th of March, the mass flowering – the 1st of April and the end - the 12th of April. The entire flowering cycle is 21 days on average.An important factor that has a significant impact on the state of the population of the species in the Reserve is the spring sowing of bulbs and tufts of plants by sultry European. It is pointed out almost every year, and evidenced by the presence of numerous fresh lanterns and ditches.