This website was created and is supported by the UNDP / GEF / Ministry of Russia project "Improving the coverage and management efficiency of protected areas in the steppe biome of Russia"
Latitudinal and altitudinal zonation
Many ways of subdividing Eurasian and Russian steppe biomes according to different characteristics (eg. botanical, geographical, zoological) have been suggested in Russian literature. According to Lavrenko et al. (1991), there are four latitudinalzonal types of steppe ecosystems on the Russian plains. These merge into each other mostly on a north-south basis between the approximate latitudes of 55° to 48°N. In some relatively small areas near mountain ranges, however, the latitudinal direction can transform into a longitudinal one. All of them also have an equivalent in the altitudinal zonation of the southern mountain ranges in the Caucasus, Urals, Altai and Sayan and in the more easterly mountain ranges of southern Siberia. The basic types are: 1) meadow steppe; 2) true feather-grass steppe; 3) dry feather-grass steppe; and 4) desert steppes. In general, the transition from meadow steppe to desert steppe corresponds to an increase in aridity (ie. evaporation exceeding precipitation). Throughout this transition, species richness, species evenness and total biomass of plant communities decrease. The proportion of above-ground plant parts decreases from 1/8 to 1/30 and the productivity reduces by a factor of 2. Plant cover becomes progressively less dense, while the flowering period over a year shortens. Corresponding changes occur with animals living in steppe ecosystems. For example, the abundance and diversity of burrowing mammals and herding ungulates increase and the composition of major groups of soil and litter invertebrates change. In addition to this latitudinal zonal transition, there are other specific steppe types that are mountain-related or which exist in locations outside of the principal steppe zone.
The steppe zone stretches along most of the Eurasian land mass from west to east, from approximately 15°E to 115° E. Within this range, there are up to seven longitudinal sectors, five of which occur within Russia. The most important boundary lies between the Black Sea-Kazakhstan steppes and the East Siberian/Central Asian (ie. Daurian/Mongolian) steppes. This boundary runs approximately through the Altai mountain range and along the Yenisei River.
The substrate greatly influences the characteristics of steppe ecosystems. The main types of substrate are sandy, stony (petrophytous), saline (solonetzic), alkaline (saz) and chalky (calciphyte, cretophyte).
Some other types of grassland ecosystems, such as forest-steppe and semi-desert communities, are closely related to steppes. In forest-steppe communities, patches of meadow steppe form a complex mosaic with forests, meadows and shrubs. The semi-desert comprises a mosaic of dry and desert steppes with communities of northern sagebrush and saltwort-sagebrush desert, halophytic deserts and saline meadows. There are also several specific variants of forest and wetland ecosystems that are not found outside the steppe zones.
Steppe is an extremely dynamic ecosystem that constantly experiences severe and extensive disturbance (Komarov, 1951; Mordkovich, 1982). All of these types of steppe ecosystems have a number of transitional variants that are either degraded (eg. heavily grazed) or recovering (eg. after heavy grazing, fallow lands, etc.). Some steppes types are represented in most parts of its range by only serial and secondary variants.
With regard to latitude and altitude, the literature divides the steppe biome into a number of different regions or subdivisions (Kucheruk, 1959; Mordkovich, 1982; Lavrenko et al., 1991; Chibilev, 1998; Nikolaev, 1999; Korolyuk, 2002).
Komarov N.F. (1951). The stages and factors of evolution of chernozem steppes plants. M.: Geographgiz. 328 p.
Lavrenko E.M., Karamysheva Z.V., Nikulina R.I. (1991). Steppes of Eurasia. L.: Nauka. 146 p.
Mordkovich V.G. (1982). Steppe ecosystems. Novosibirsk: Nauka, SB. 206 p.
Chibilev A.A. (1998). The bases of steppe science. Orenburg: DIMUR. 120 p.
Nikolaev V.A. (1999). The landscapes of Asiatic steppes. M.: MSU. 288 p.
Koroliuk A.Yu. (2002). Flora// Steppes of Central Asia / Gadjiev I.M. et al. Novosibirsk: SB RAS. P. 45-94.
Kucheruk V.V. (1959). Steppe faunistic complex of mammals and its place in palaearctic fauna // Population geography of terrestrial animals and research methods. M.: AS USSR. P. 45-87.
A collective monograph reflects results of the study in the frame of the RSF grant № 14-17-00320 «Development of integral indexes to optimize a supply of land structure and modernize nature management in the steppe regions of Russia»