Vegetation at the taiga forest-steppe borderline in the western Khentey Mountains, northern Mongolia

Vegetation of an area of 500 km(2) in the western Khentey Mountains, northern Mongolia is phytosociologically classified with the help of 254 releves. Twenty-one main vegetation units are described. The study area is situated at the inter-face between the western Siberian dark taiga, the eastern Siberian light taiga and the Mongolian-Daurian forest steppe. A small-scale pattern of these three major vegetation types was found depending on site characteristics. Dark taiga forests of Pinus sibirica, Abies sibirica, Picea obovata, and Larix sibirica grow at the most humid sites. Light taiga forests dominated by Larix sibirica and Betula plaophylla occur on relatively dry northern slopes of the lower montane belt. Sun-exposed, southern slopes of the lower montane belt are covered by montane meadow and mountain steppe. DCA ordination suggests that the distribution of vegetation types depends on water supply and altitude.