The vegetation of the small rivers of Novosibirsk Region (a syntaxonomic essay)

Information on the aquatic and semiaquatic vegetation of the major watercourses of West Siberia is relatively scarce, while this of small rivers is practically absent. There are 430 rivers whose length exceeds 10 km within the Novosibirsk Region. The aim of our work was to study the phytocenotic diversity of their aquatic and semiaquatic vegetation.

130 geobotanical relevés were performed by the authors in July–August 2003–2005. The object was aquatic communities formed by true aquatic (submergent and floating-leaved) plants and semiaquatic ones with emergent plants and these of water′s edge. In total 10 watercourses were studied (Table 1): 2–3 in each of five geomorphologic regions within the forest-steppe zone (Table 2). The upper, middle and lower courses (Fig. 1, Table 1) with the length of 2–2.5 km were studied in each case to ensure the 4–5 repetition of main elements (stream pools and ridges) that would give a reliable information on their flora and vegetation. The sample plots were selected above the settlements, whenever possible in sites with no to intensive anthropogenic impact.

The data were collected according to J. Braun-Blanquet (1964) approach. The relevés were done on the sample plot of 100 m² placed in the most homogeneous part of the community or, in case of its smaller area, within the natural boundaries. The following scale was used for abundance estimation: r — the species is extremely rare; + — rare, small cover; 1 — the number of individuals is large, the cover is small or individuals are sparse, but the cover is large; 2 —cover of 5–25 %; 3 — 26–50 %; 4 — 51–75 %; 5 — more than 75 %. The date on water depth, transparency (on a white Secchi disk with a diameter of 30 cm), temperature and the flow rate were obtained. The soil mechanical composition and color, the degree and nature of anthropogenic impact on vegetation and river banks were quantified. Water samples for general chemical analysis were taken in the middle course of each river.

Computer programs TURBOVEG and MEGATAB (Hennekens, 1996) were used for database. The syntaxonomic affiliation of phytocenoses was determined using modern literature (Bobrov, Chemeris, 2006; Vegetace..., 2011; Chepinoga, 2015; Landucci et al. 2015; Mucina et al., 2016, etc.).

36 associations and 3 communities belonging to 12 alliances, 9 orders, and 5 classes have been identified (Tables 3–14, Fig. 2–9). Such great syntaxonomic diversity is determined by the significant ecotopic variety, the variability of substrates, the wide range of water flow rates and the different water trophicity. For comparison, 26 associations, 13 variants, 2 communities were identified in the study of 50 rivers of Lithuania (Sinkyavichene, 1992); altogether 84 associations are known for the Upper Volga region as a whole (Bob­rov, Chemeris, 2006), while 45 ones were recorded previously in 130 watercourses of this region (Bobrov, 1999).

The most diversу is the classPhragmito-Magnocaricetea Klika in Klika et Novák 1941 (18 associations and 1 community); Potamogetonetea Klika in Klika et Novák 1941 includes 12 associations and 1 community. Lemnetea O. de Bolòs et Masclans 1955 class is represented by 4 associations and 1 community. The predominance of the Phragmito-Magnocariceteaclass is also noted in small and medium-sized rivers of other regions (Bobrov, 1999; Sinkyavichene, 1992; Bobrov, Chemeris, 2006).

Communities of the river rolls and streams belonging to the allianceBatrachion fluitantis Neuhäusl 1959 are character for the small rivers of the Novosibirsk Region just as for these of the Upper Volga region and Lithuania (Bobrov, 1999; Sinkyavichene, 1992; Bobrov, Chemeris, 2006, etc.). Сharacter species for this alliance are Batrachium trichophyllum, Nuphar lutea f. submersa, Scirpus lacustris f. fluitans, Sparganium emersum var. fluitans, Veronica anagallis-aquatica f. submersa and some others. А contribution to the syntaxonomic diversity of this alliance in the Upper Volga region is significant: 8 associations and 2 communities (Bobrov, Chemeris, 2006).

Communities of ass. Caricetum gracilis Savich 1926, quite frequent in the study area (Table 15), occur on the stable banks of the placid sections of river beds. Common associations are Sparganietum emersi Mirkin, Gogoleva et Kononov 1985,Batrachio kauffmannii–Sparganietum emersi Bobrov 2001,Schoenoplectetum lacustris Chouard 1924 and Nymphaeo albae–Nupharetum luteae Nowinski 1927. The most frequent is ass. Sparganietum emersi that is explained by the wide distribution of fine alluvium fractions optimal for Sparganietum emersi. The alluvial deposits are formed as a result of channel processes. The cenoses of Sparganium emersum helophytic or submerged forms occur in all studied rivers. Communities of 8 associations and 2 communities are moderately common, these of 12 ones and 1 community are rare, 11 associations are represented by single communities.

Information on small river macroalgae cenoses in the study area is partially reflected in the paper published earlier (Bobrov et al., 2005).

Key words: aquatic and semiaquatic vegetation, association, Potamogetonetea, Phragmito-Magnocaricetea, small rivers, Novosibirsk Region

Section: Articles

How to cite

Kipriyanova L. M., Kleshchev M. A. 2019. The vegetation of the small rivers of Novosibirsk Region (a syntaxonomic essay) // Vegetation of Russia. N 35. P. 3–27. https://doi.org/10.31111/vegrus/2019.35.3

Received May 22 2018

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