SPATIAL DISTRIBUTION AND VITAL STATUS ASSESSMENT OF NATURAL POPULATIONS OF TAXUS BACCATA IN THE CRIMEAN MOUNTAINS

The article gives the results of studying the spatial distribution of stands of Taxus baccata L., growing in the Mountain Crimea and detailed analysis of four significant populations located at varying altitudinal levels: the western location at an altitude of 220-440 m – “Belbek Yew Grove”, near Maloye Sadovoye village; the southern location at an altitude of 560-800 m in the Yalta Mountain-Forest Nature Reserve – “Tuzler”, on the way from Uchan-Su to Ai-Petri ; the eastern location at an altitude of 860-960 m in the valley of the Su-At River; the northern location at an altitude of 1040-1200 m. – “Yew Gorge”, on the Lower Plateau of Chatyr-Dagh. The studies allowed specifying the boundaries and total area of the natural population of 427 ha. Vital status, growth and development features of T. baccata are assessed, facilitating the identification of the most favorable altitudinal range for the growth of this rare species. It is shown that on average about 20 % of all individuals belong to the second category and are weakened trees. These individuals exhibit a reduction in crown density of about 30 % due to premature fall or underdevelopment of needles, thinning of the skeletal structure of the crown, presence of dying branches and various kinds of damage (leaf-eating, diseases). The population in the Su-At River valley at an altitude of 860–960 m, where more than 50 % of individuals are affected, stands out most clearly from the overall statistics. It is revealed that the optimal altitudinal range for growth and development of T. baccata in the conditions of Crimean Mountain is not clearly expressed, as currently yew is subjected to a large number of limiting factors, including natural and anthropogenic impacts.