VEGETATIVE COVER OF THE MOUTH OF THE CHESNAVA RIVER (YAROSLAVL REGION)

Abstract

Rivers are the basis for the creation of reservoirs, which can radically change the structure and functioning of aquatic and terrestrial ecosystems. Despite the fact that small rivers have long become a model object of research, work on them remains relevant to this day. The purpose of our study was to study the vegetation cover of the mouth section of the small river Chesnava, flowing in the Nekouz and Breitovsky districts of the Yaroslavl region and flowing into the Rybinsk reservoir. The most typical here are open zones with a depth of 0.9–2.5 m, shallow waters 0.1–0.8 m deep with silty, silty-sandy and sandy soils, and strips of periodically flooded coasts with sandy and silty soils that are drained after the water recession. The flora contains 82 species from 30 families and 57 genera. The dominant ecogroup is hygrophytes, cryptophytes and hemicryptophytes predominate in life forms, and boreal and holarctic species in the zonal-regional relation. The vegetation of the river is represented by 19 associations, united in 14 formations, the main ones of which are: Lemna-Hydrochairetum morsus-ranae, Typhetum angustifoliae, Phalarito arundinaceae-Glycerietum maximae, Sparganio emersi-Eleocharietum palustris, Heteroherboso-Eleocharietum palustris, Careto acutae-Phalaroidetum arundinaceae. The expansion of the shallow and gently sloping coastal zone contributes to the active overgrowing of the investigated area.