Title
Transvolgian herb-grass steppes (Stipa zalesskii) with Stipa korshinskyi, Seseli hippomarathrum, Onosma simplicissima
Geographical distribution
Country/territory
Russia: small strip in the interfluvial region Volga-Ural at the middle course of these rivers south of Samara, lower situated part of the Obščij Syrt (Samara upper course) and highlands north of the Irgiz. In the east these steppes reach down from the lower foothills of the Ural as far as to west Kazakstan
area frequency
11 polygons.
Scientific names of main plant communities and their most common synonyms (with author citation)
Stipeta zalesskii herbosa, Festuceta valesiacae herbosa.
Structural feature of the main community(ies) (layers, life-forms, etc.)
The horizontal and vertical structure corresponds to that of types M5 and M6. The east Pontic-Kazakh species Stipa zalesskii, the Pontic-Kazakh Stipa lessingiana and the western palaeoarctic species S. capillata and Festuca valesiaca dominate. Koeleria macrantha and Phleum phleoides are also widespread. Herbs are quite frequent and ecologically heterogeneous, together with the rather xerophytic typical steppe species (e.g. Aster oleifolius, Jurinea lineariloba, Seseli hippomarathrum) Mesoxerophytic and mesophilous species (e.g. Scabiosa ochroleuca, Artemisia latifolia) occur here.
Dominant and most frequent species in different layers
Herb layer
Stipa zalesskii, Stipa capillata, Festuca valesiaca, Koeleria macrantha, Phleum phleoides, Thymus kosteleckyanus, Veronica incana, Hieracium echioides, Phlomis tuberosa, Aster oleifolius, Jurinea lineariloba
Moss layer (incl. lichens)
No details
Diagnostically important species
Stipa zalesskii, Stipa korshinskyi, Seseli hippomarathrum, Clausia aprica, Centaurea sibirica, Onosma simplicissima
Ecological variants
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Geographical variants (geogr. differential species)
Typical species for the southern Urals such as Elymus bungeanus subsp. pruiniferus, Dianthus acicularis, Sedum hybridum.
Natural accompanying vegetation (most important units in complex with the name giving mapping unit, scientific names)
Festuca valesiaca steppes in complex with halophytic dwarf semi-shrubs; petrophyte communities; trans-Volgian tomillares and tomillares steppes (Matthiola fragans, Silene suffrutescens, Hedysarum cretaceum) on limestone or marl (Obščij Syrt); small-area incidences of east European open pedunculate oak forests (Quercus robur) with steppe species (Caragana frutex, Prunus tenella, Brachypodium pinnatum) at valley slopes.
Adjoining climax and permanent vegetation (with numbers of mapping units)
steppes (M3, M6, M10, M14), salt meadows (P34), alluvial forests (U12, U13, U14).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
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grassland (meadows, pastures, herb-rich communities)
Pasture grounds.
arable land (characteristic weed communities)
Fields (Wheat).
settlements (typical ruderal vegetation)
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Site conditions of the mapping unit
Landscape type, geomorphology
trans-Volgian lowlands, plains
Altitudinal belt and/or altitudinal range
lowland; in the west 100 m, in the east 120-140 m (maximum 298 m)
Geology (bedrock)
chalky clay (Tertiary, Cretaceous, Jurassic, Triassic, Permian)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
southern, here and there solonetz-like black earths; (haplic sodic kastanozems; haplic chernozems)
soil texture
sandy-loamy, partly stony
soil moisture, water balance
moderately dry
soil fertility
mesotrophic, meso-eutrophic
Climate incl. local climate
climate type (following Walter & Lieth)
VII(VIII)
average annual temperature
3-4 °C
average annual precipitation
300-350 mm
average temperature of the warmest month
20-22 °C
average temperature of the coldest month
-16 to -14 °C
local climate or other climatic peculiarities
moderately continental.
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
The whole area has been transformed into arable land. Only remnants of petrophytic steppes and herb-rich petrophyte communities at stony slopes as well as smaller islands of oak forest, particularly in hollows, remain preserved. Conservation areas are lacking.
endangered communities, species worthy of protection in natural vegetation
The vegetation of shallow sites is especially valuable, especially on Cretaceous- or chalky clay-substrates along river banks in the steppes of Transvolgia (Obščij Syrt). This vegetation consists of calciphilous petrophytes with a disjunct distribution (Matthiola fragrans, Silene cretacea, Lepidium meyeri, Hedysarum cretaceum, Linaria cretacea).
causes of endangerment
Agricultural use.
required measures for protection and restitution
Establishment of conservation areas for the semi-natural remnants.
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
No details
of characteristic substitute communities worthy of protection
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Most important references (author, year)
Krašenninikov & Kučerovskaja-Rožanec 1941; Rodin 1933; Tarasov 1968; Tarasov 1971; Tarasov 1975
Compiled by
Z. Neuhäuslová based on documents by Z.V. Karamyševa
