Syntaxonomical overview of vegetation of water bodies of the Vychegda river basin (European North- East of Russia)

The aim of our study was to reveal coenotical diversity of higher aquatic and semi-aquatic vegetation in the basin of the Vychegda river. The study area lies in latitude 5955 - 6430, longitude 4630 - 5610. The main part of the area is located in the middle taiga subzone; only upper reaches of the Vym river are located in the northern taiga subzone. Coenotical structure was analyzed based on more than 2500 geobotanical descriptionss of aquatic and semi-aquatic vege- tation made during 1999-2015. Syntaxonomy was made based on Braun-Blanquet classification [13-15]. By the moment, coenotical diversity of higher aquatic and semi-aquatic vegetation in the Vychegda river basin includes 81 associations and three not classified communities from 22 unions and 9 classes of floristic classi- fication: Platyhypnidio-Fontinalietea antipyreticae (2 ass.), Lemnetea (10 ass.), Potametea (30 ass. and 1 comm.), Phragmito-Magno-Сaricetea (30 ass. and 1 comm.), Montio-Cardaminetea (1 ass.), Agrostidetea stoloniferae (1 ass.), Litto- relletea (2 ass.), Isoëto-Nano-Juncetea (1 comm.), Bidentitea tripartitae (4 ass.).