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Altai mountain-steppe province

The Altai mountain-steppe province comprises the western part of the Altai, Tarbagatai and the steppe mountains of Dzungaria. The steppes here are the same bunch grass steppes that are usually found in the Trans Volga-Kazakhstanian province. The zonation includes steppes, brushwoods, forests (mainly of Larix sp., and in the northwest of Abies sp.), high mountains meadows, and fragmentary tundra.

The West-Altai subprovince (Rachkovskaya and Bragina, 2012). This area is located in the most humid part of the Altai Mountains, within the westerly fl ow of the atmospheric circulation. In the lower part of the mountains, steppes and brushwoods are characteristic. The forests at the middle part of the mountains consist of Abies sibirica, sometimes mixed with Pinus sibirica. On the high mountains colourful montane meadows dominate.

West-Altai. Ulbinsky Range. Foto: Smelansky I. E.

The Kalba-South Altai subprovince (Karamysheva and Rachkovskaya 1973; Rachkovskaya and Bragina, 2012 ) includes territories with the East-Kazakstanian-Western Altai type of zonation (Volkova 1994 ). The belt of brushwoods is especially typical in just this subprovince of the Altai. They are formed by Rosa spinosissima, Spiraea crenata, S. hypericifolia, S. trilobata, and Amygdalus ledebouriana, which alternate with feather grass steppes (Stipa zalesskii) and fescue – (Helictotrochon desertorum) – feather grass steppes and fescue steppes.
The forests are variable though mainly of Larix sibirica. In the Kalba Mountains Pinus sylvestris occurs on the granites. There are low herbaceous cryophytic meadows, including communities of Kobresia. Only in the east of this subprovince the tundra is found in Kazakhstan (moss – lichen tundra as well as herb and shrub tundra with dwarf Salix spp. and dwarf Betula rotundifolia).

Southern Altai. Kalbinsky Range. Foto: Smelansky I. E.

The Saur-Tarbagatai subprovince (Karamysheva and Rachkovskaya. 1973; Rachkovskaya and Bragina, 2012). Here steppes are common in the piedmonts and low mountains. Stipa capillata and
Stipa lessingiana steppes with Calophaca soongorica and its brushwoods are peculiar to the Tarbagatai (Stepanova 1962). The shrub belt is present, but it is fragmentary (Spiraea hypericifolia, S. trilobata, S. crenata. Caragana frutex, Cerasus tianschanica, Calophaca soongorica, Amygdalus ledebouriana). In Saur the belt of Larix sp. forests is found mainly on north slopes (expositional forest-steppe). Large areas of the high mountains are occupied by subalpine and alpine meadows.

Tarbagatay Mountains. Foto: Smelansky I. E.

In the deserts, within the Sahara – Gobi phytogeographic region (Lavrenko, 1965 ) , steppes are found in the Tien Shan Mountains, within the Dzungaria-North Tien Shan province, mainly on the piedmont plains and low mountains, as well as in some areas in the high mountains (Botanical geography of Kazakhstan and Central Asia 2003).