Communities of class Querco-Fagetea Br.-Bl. et Vlieger in Vlieger 1937 in Sudost-Desna watershed area (Bryansk region)

The broad-leaved forest vegetation of the class Querco-Fagetea in the Sudost-Desna watershed area is represented by 7 associations and 3 subassociations. 2 associations and 1 subassociation are described for the first time. The syntaxa are divided by the groups of differential species and Sorensen-index values (the amplitude of the differences is 0.64—0.81). The greatest syntaxonomical diversity is characteristic for the polessian and subpolessian landscapes where associations Mercurialo perennis—Quercetum roboris, Geo rivali—Quercetum roboris, Galio palustris—Quercetum roboris, and Vaccinio myrtilli—Quercetum roboris, subass. Lathyro nigri—Quercetum roboris laserpitietosum latifolii occur. On the territory of the opolje landscapes forests are connected with the ravine complexes where assocations Mercurialo perennis—Quercetum roboris, Ulmo laevis—Fraxinetum excelsioris, subass. Lathyro nigri—Quercetum roboris laserpitietosum latifolii are common. The flood-plain broad-leaved forest vegetation is represented by two subassociations: Filipendulo ulmariae—Quercetum roboris typicum and F. u.—Q. r. veronicetosum longifoliae.