ECOLOGICAL-PHYTOCENOTIC ANALYSIS OF THE FIELD LAYER OF URBAN RECREATIONAL FORESTS (ON THE EXAMPLE OF KALUGA AND OBNINSK)

Abstract

The aim of this study is to study the diversity of the ecological-coenotic structure of the field layer of the residual urban forests, using as an example the cities Kaluga and Obninsk, which have different approaches to the conservation of residual forest communities in the city. Obninsk practices the conservation of forest zones that have entered the urban environment as recreational objects, while in Kaluga, such forest communities are in a state of interrupted succession and have experienced forestry activities. The objectives of the study are to study the ecological-coenotic and ecological-biological spectra of the field layer of forest ecosystems, and to identify adventive and protected plant species. The study took place in 2014-2015. In the forest communities under study, 30 sites were selected for geobotanical descriptions by the Braun-Blanquet method at different periods of the growing season (in June and August) to fully cover floristic diversity. A total during the observation period were made 240 floristic descriptions. Kaluga city forests turned out to be more susceptible to negative changes occurring in conditions of recreational forest management. The field layer of the Kaluga forest recreational zones turned out to be more susceptible to negative changes occurring under the influence of anthropogenic pressure, in comparing with the Obninsk forest recreational zones. This is expressed in the proportion of ecological-coenotic and ecological-biological groups, the presence of a greater number of alien species in the studied communities of Kaluga, which indicates greater resistance to the recreational load of the city forests of Obninsk. For example, the share of the group of forest habitats is much higher in Obninsk, where forest species make up more than half of all types of grass layer (54,2%). In the Kaluga forests, the share of forest habitats is lower and amounted to 47,5%. The discovered difference in the stability of the field layer of the Obninsk forests is presumably due to the strategy of their conservation in the urban area in a state of natural succession. The practical significance of the results obtained can be the possibility of using them to determine the degree of negative changes in recreational forests. The direction of further research can be directed at organizing monitoring of the urban forests of Kaluga and Obninsk according to the state of the field layer.