STATE OF TILIA CORDATA MILL. AND ULMUS GLABRA HUDS. COENOPOPULATIONS IN THE FORESTS OF PETROZAVODSKY URBAN OKRUG

Relevance and purpose. Cenopopulations of deciduous tree species at the northern border of the range are of particular scientific interest as objects of biological diversity. The relevance of the work is associated with the need to organize monitoring of these rare objects in the forests of the Petrozavodsk Urban Okrug by cause of increasing anthropogenic pressure. Assessment of the state of valuable nature conservation objects has not only scientific, but also economic interest in the field of ecosystem services, taking into account those functions of natural ecosystems that ensure the quality of people’s living standards.Material and methods. During 2017–2018 a detailed study of the cenopopulations of Tilia cordata and Ulmus glabra was carried out on two model plots within the boundaries of the Petrozavodsk urban district. The area, abundance, ontogenetic structure of cenopopulations was determined using the standard technique of cenopopulation studies, taking into account the characteristics of specific species. Results and conclusions. The studied cenopopulations are isolated and small (up to 23 hectares). They were forming during the secondary succession anthropogenic felling and fires more than 100 years old. According to the ontogenetic spectrum, cenopopulations are normal mature, have an ontogenetic spectrum with a maximum on immature individuals, thus, cenopopulations are characterized by a normal turnover of generations. Generative reproduction and large generative trees high 16–24 m up to 120 years old are rare for the northern regions.