Floodplain steppe meadows of the Eastern part of the Altai-Sayan mountain region

N. I. Makunina, L. P. Parshutina

DOI: https://doi.org/10.31111/vegrus/2017.30.78


In South Siberian mountains floodplain steppe meadows can be found only within steppe and forest-steppe belts. In the eastern part of the Altai-Sayan mountain region (ASMR) these belts occupy large intermontane depressions, making up the submeridional range at 56–50° N (Fig. 1). The northern part of this range consists of four large depressions (the Nazarovo, North Minusinsk, Middle Minusinsk and South Minusinsk). To the north, the Nazarovo depression merges into the West Siberian plain. The southern border of the South Minusinsk depression is the West Sayan. The southern part of range includes the Turan-Uyuk and Central Tuvinian depressions.

Each depression has unique set of bioclimatic characteristics. The West Sayan is considered a basic climatic barrier of ASMR, it separates the northern windward and southern leeward slopes of mountain system. In the mountains, the basic climatic parameters — temperature and precipitation — are determined by latitude and altitude. The Nazarovo and Minusinsk depressions (53–56° N) are located in the latitudes of forest-steppe zone at 400–600 m above the sea level. The Turan-Uyuk and Central Tuvinian depressions (50–53° N) are situated in the latitudes of steppe zone, their altitudes vary from (600) 800 to 1000 m. The rain shadow effect is an important local factor in the climate of large intermountain depressions. Due to this effect the western parts of the Minusinsk depressions have the steppe vegetation instead of forest-steppe one, and the western part of Central Tuvinian depression — the bunchgrass steppe instead of herb-bunchgrass one. The annual rainfall in the eastern parts of the Minusinsk depressions is 400–500 mm, in their western­ parts — 300–400 mm; in eastern part of Central Tuvinian depression annual rainfall is 300–350 mm, in western part — 250 mm. In Nazarovо depression, the annual sum of temperatures above 10 °C is 1400–1600 °C, in the North-Minusinsk depression — 1600–1800 °C, in South-Minusinsk one — 1800–2000 °C. In the Turan-Uyuk depression, the effective heat sum is 1600–1800 °C, in the Central Tuvinian depression — 1800–2000 °C.

The main watercourses of the Minusinsk depressions are the Yenisey and Chulym rivers. The Chulym is one of the main tributaries of Ob river. In the Minu­sinsk depressions, the Yenisey has two large tributa­ries: Abakan and Tuba. Many small rivers cross the depression bottoms. All rivers of the Tuvinian depressions belong to the upper part of the Yenisey basin. The origins of the Yenisey are Biy-Khem and Kaa-Khem rivers, large tributaries — the Elegest and Khemchik. There are not so many small rivers. The rivers mentioned above originate in different mountain ranges; have various sizes and a large variety of habitats. The prevailing vegetation of the river valleys of the Minusinsk depressions are meadows, so steppe meadows are widespread. The river valleys of the Tuvinian depression are dominated by steppes, so steppe meadows occupy small area.

The syntaxonomy of Siberian steppe meadows is not worked out clearly. Steppe meadows of Western Siberia and the western part of ASMR are attributed to the alliance Trifolion montani Naumova 1986 of order Galietalia veri Mirk. et Naumova 1986 of class Molinio-Arrhenatheretea (Makunina et Maltseva, 2008, 2012; Tishchenko et al., 2015). Alliance Hordeion brevisubulati Konon. 1986 of order Hordeetalia brevisubulati Konon. 1986 of class Hordeetea brevisubulati Mirk. 1986 includes the steppe meadows of “alas” in Yakutia (Mirkin et al., 1992). The area under discussion lies on the periphery of the eastern part of Trifolion montani area and to the South-West of the area of the alliance Hordeion brevisubulati.

The information about steppe meadows of Eastern part of ASMR is fragmentary (Rastitelniy…, 1976; Rastitelniy…, 1985).

This study is based on the analysis of 260 geobotanical relevés made in the valleys of 47 rivers (21 — in Minusinsk depressions, 26 — in Tuvinian depressions). The set includes the relevés of steppe meadow of different river types (large, medium, small), located in different parts of the studied region. The typical feature of these communities is the permanent coexistence of steppe and meadow species with negligible part of meadow-steppe herbs. All steppe meadows under discussion are similar in appearance. Tall grasses, various in different associations, form a sparse upper sublayer. Depending on the intensity of use, the main part of the herbage can be located in the middle sublayer or in the bottom one. In the middle sublayer, grasses predominate (Bromopsis inermis, Poa angustifolia, Elytrigia repens). Herbs tolerant to grazing (Potentilla bifurca, Amoria repens) make up the bottom sublayer.

We have revealed 6 associations of steppe meadows. Ass. Potentillo bifurcaePoetum angustifoliae, Potentillo bifurcaeLeymetum dasystachyos, Potentillo bifurcaeHordeetum brevisubulati are typical for Tuvinian depressions, ass. Artemisio laciniataeKoelerietum delavignei, Trifolio pratensisKoelerietum delavignei и Trifolio pratensisFestucetum valesiacae — for Minusinsk ones (Table 1). The basic bioclimatic barrier of ASMR — the West Sayan divides their areas.

The ordination of new associations along the gradients of moisture supply (horizontal axis) and richness-salinity of soils (vertical axis) demonstrates that areas of associations form two ranges — the Minusinsk and Tuvinian. Every association of the Minusinsk range has corresponding association of the Tuvinian range (Fig. 2). DCA-ordination (Fig. 3) and cluster analysis (Fig. 4) of syntaxa from the South Urals, West Siberia, Yakutia and new associations have detected the specificity of the last ones, so a new alliance Potentillo bifurcaePoion angustifoliae (order Galietalia veri, class Molinio-Arrhenatheretea) has been described. It comprises steppe meadows of the Eastern part of ASMR. 

Nomenclature type (holotypus) — ass. Potentillo bifurcaePoetum angustifoliae.

The diagnostic features of the new alliance:

1. Diagnostic species: Potentilla bifurca, Ranunculus propinquus, Silene repens;

2. The lack or rare occurrence of some constant species of alliance Trifolion montani such as Centaurea scabiosa, Dactylis glomerata, Filipendula vulgaris, Inula salicina, Leu­canthemum vulgare, Origanum vulgare, Pimpinella saxifraga, Seseli libanotis.

Key words: meadows, classification, floodplain, the Altai-Sayan mountain region

Section: Articles

How to cite

Makunina N. I., Parshutina L. P. 2017. Floodplain steppe meadows of the Eastern part of the Altai-Sayan mountain region // Vegetation of Russia. N 30. P. 78–93. https://doi.org/10.31111/vegrus/2017.30.78

Received January 9 2017


Makunina N. I., Maltseva T. V. 2008. Rastitelnost lesostepnykh i podtaezhnykh predgoriy Altae-Sayanskoy gornoy oblasti [Vegetation of forest-steppe and subtaiga foothills of the Altai-Sayan mountain region] // Sibirskiy botanicheskiy vestnik: elektronniy zhurnal [Siberian Botanical Bulletin: e-journal]. Vol. 3. Issue 1–2. P. 45–156. URL: http://www.csbg.nsc.ru/uploads/journal.csbg.ru/pdfs/i4.pdf  (In Russian).

Makunina N. I., Maltseva T. V. 2012. The meadows of the North Altai // Vegetation of Russia. N 20. P. 48–66. (In Russianhttps://doi.org/10.31111/vegrus/2012.20.48

Mirkin B. M., Kononov K. E., Gogoleva P. A., Burtseva E. I., Naumova L. G. 1992. The floodplain grasslands of the Middle Lena-River II. Classification // Folia Geobotanica et Phytotaxonomica. Vol. 27. P. 247–300 https://doi.org/10.1007/BF02853016

Rastitelniy pokrov i yestestvennye kormovye ugodya Tuvinskoy ASSR. [Vegetation cover and natural forage grasslands of Tuva ASSR]. 1985. Novosibirsk. 256 p. (In Russian).

Rastitelniy pokrov Khakasii. [Vegetation cover of Khakassia]. 1976. Novosibirsk. 423 p. (In Russian).

Tishchenko M. P., Korolyuk A. Yu., Makunina N. I. 2015. Meadows of north forest-steppe and subtaiga on the Tobol and the Irtysh watershed // Vegetation of Russia. N 26. P. 129–147. (In Russianhttps://doi.org/10.31111/vegrus/2015.26.129