The ecoregion stretches some 2,500 km from the Kuznetsk Alatau mountains in the west, across the western and eastern Sayan Mountain ranges, to the southeastern shores of Lake Baikal.[2] The ecoregion covers the forested mid-altitudes of the mountains, with a lower bound ranging from 600 to 900 meters about sea level (depending on local conditions), and an upper bound of 1,800 meters. This ecoregion is one of high biodiversity, due to its position on the meeting lines of climate and floral zones, and the many micro-climates created by the mountainous terrain and steep river valleys.[3]
Because of its altitude and distance from the ocean, the ecoregion has a subarctic climate (Köppen climate classification Dfc). This indicates a continental climate characterized by short, cool summers, and very cold, long winters, with wide differences between day and night temperatures. This region is also heavily influenced by the high barometric pressures over Mongolia. The Altai mountains on the west of the ecoregion capture humidity in the winds from the west; precipitation is accordingly higher on the western side of the ecoregion than the drier east.
The mid-altitude forest belt can be divided into three sub-zones. The highest is the 'Light Needle-Leaf Sparse Taiga' zone (1,400 meters to 1,800 meters), an open canopy forest of Larix sibirica (Sibirian larch), with notable shrub and grass layers. The 'Dark Needle-Leaf Taiga' zone (900 meters - 1,400 meters) if dominated by Abies sibirica (Siberian fir) and stands of Pinus sibirica (Siberian pine) and Picea obovata (Siberian spruce). The 'dark taiga' zone (600 meters to 900 meters) has the same trees as the middle sub-zone, but more vertically developed shrub and grass layers, and richer soil. Over 800 species of flora are recorded in the ecoregion.
Khakassia Nature Reserve ("Khakassky"). An IUCN class Ia "strict ecological reserve" (aZapovednik) covering two large mountain areas (alpine and mountain-steppe), and a cluster of seven steppe sites located within the left bank of the Minusinsk Hollow. (Area: 2,675 km2).
Shushensky Bor National Park. An IUCN class Ia "strict ecological reserve" (aZapovednik) located in the extreme southwest of Siberia, in the northern foothills of the Western Sayan Mountains. (Area: 392 km2).
Tunkinsky National Park. An IUCN class Ia "strict ecological reserve" (aZapovednik) located in a mountainous region centered on the Irkut River valley (also referred to as the Tunka Valley) that continues from the rift valley of Lake Baikal southwest to the border of Mongolia. (Area: 11,837 km2).
Ubsunur Hollow Biosphere Reserve. An IUCN class Ia "strict ecological reserve" (aZapovednik) located a fragile mountain hollow or depression located on the territorial border of Mongolia and the Republic of Tuva in the Russian Federation among the mountains — Tannu-Ola Mountains, and the Altay Mountains region. (Area: 10,688 km2).
Lake Khövsgöl National Park (Mongolia). The park covers territory surrounding Lake Khovsgul, the largest freshwater lake in Mongolia (over 1,000 square miles and averaging over 450 feet in depth). (Area: 8,381 km2)
Tengis-Shishged National Park (Mongolia). Covers the lower Shishged River as if flows west from the Darkhad Valley in northern Mongolia. The landscape is one of high peaks with steep sides and wide glaciated valleys. (Area: 8,757 km2)
