Syntaxonomy of the vegetation class Phragmito-Magno-Caricetea of Kremenchug reservoir

Анотація

Introduction. Vegetation-class Phragmito-Magno-Caricetea united the group of air-aquatic vegetation in shallow areas of the reservoir area. In the territory of reservoir the grouping class spread in the upper and middle parts, at the bottom are less common. Соеn mainly extracted form thickets width from 2 to 10 meters, as well as other forms, particularly around the islands. Withstand fluctuations in the water level of 10 to 80 cm during the growing season. Grass in grouping represented by three sub-levels.

Purpose. Conducting the research of airborne aquatic vegetation in the Kremenchug reservoir area for floristic approaches Braun-Blanquet and the development of its syntaxonomical scheme.

Results. Flora of the grouping class Phragmito-Magno-Caricetea has 57 species of vascular plants belonging to 32 families. The value of monocots and dicots is 0.9: 1.1, it is different from the higher classes of aquatic vegetation, where dominated monocots. Most species belong to Magnoliophyta and only one to Polypodiophyta, one to Equisetophyta. The largest number of representatives have the families of Cyperaceae and Poaceae, least – the Brassicaceae, Apiaceae, Iridaceae. Biomorphological analysis shows the predominance hemikryptofitiv (48.4%), less kryptofitiv helofitiv (29.7%), even less terofitiv (11.8%). A significant percentage of the latter points to the strengthening of synanthropization groups. In ecological spectrum to the moisturizing factor observed the prevalence of hygrophytes (43.5%) and hidromezofitiv (22.3%), inspite of the northern areas, where dominated mesophytes and hihromezofity. In geographical spectrum quantitatively dominated by zonal-type the northwind meridional (23.4%), temperate-meridional (13.4%) and plyuryzonalni (11.5%) species. Diagnostic species of the class are Alisma plantago-aquatica, Equisetum fluviatile, Galium palustre, Lycopus europaeus, Lythrum salicaria, Phragmites australis, Polygonum amphibium, Rumex hydrolapathum, Rorippa amphibia, Scutellaria galericulata, Sium latifolium, Stachys palustris. They are all presented for the Ukrainian class in general and some reservoirs in Russia. At the territory of reservoir the class represented by four items Nasturtio-Glycerietalia, Phragmitetalia and Bolboschoenetalia maritime, Magnocaricetalia.

Conclusion. The grouping of the vegetation class Phragmito-Magno-Caricetea in the Kremenchug reservoir area is marked by some features, such as: have less representation of attached embedded class types Potametea. From natural habitats groups, differ with lower floristic composition of соеn and less projective cover of some diagnostic species. At the territory of reservoir to the floristic composition associations are often include rare species Trapa natans and Salvinia natans, which need of protection. Class of соеn widespread in areas with layer of water from 30 to 80 cm and the minor fluctuations of water level during the vegetation and sandy, silty-sandy bottom sediments. Lowering the water level by 10-15 cm stimulates the development of grouping.