BROAD-LEAVED FORESTS OF THE SOUTHEASTERN TULA REGION
The remained mesophyte broad-leaved forests of the southeastern Tula Region, significantly transformed by the human, represent characteristic forest vegetation of a transitional stripe from the zone of broad-leaved forests to the forest-steppe. In terms of J. Braun-Blanquet approach, they belong to widespread in the Central Russia association Fraxino excelsioris-Quercetum roboris Bulokhov et Solomeshch 2003 uniting the Central Russian and Volga mesophyte forests of broad-leaved and forest-steppe zones beyond the distribution of Picea abies on flat interfluves. Communities of the association in the studied region vary in structure and composition of coenofloras, and are united in 3 variants and 3 facies which reflect a succession stage, the nature of the forest disturbance, and have expressed ecological distinctions of habitats. The analysis of spectra of geoelements and polyzonal groups of the mesophyte broad-leaved forests of the southeastern Tula Region and the regions located to the south-west (northern part of the Upper Dnieper basin, zone of broad-leaved forests) and basin of the Vorskla (Central Southern forest-steppe) shows their floristic differentiation. Based on the distinctions in the coenofloras structure and the character of botanical-geographical spectra, the forests of the studied region are to be classified as a typical subassociation (F.-Q. typicum) characteristic of the northern part of the association range.