Preliminary list of mosses of the Sengilen Range (the Republic of Tuva)

Sengilen Range is a part of the vast highlands in the south-east of the Republic of Tuva. The range is sub-latitudinal, about 150x90 km, it is located within 49°45'-50°35'N and 95°30'-97°40'E. Along with other ridges of Southern Tuva, Sengilen forms the world watershed between the Arctic Ocean basin and the drainless region of Central Asia. In phytogeographic terms, Sengilen marks the border of the Boreal and Ancient Mediterranean floristic sub-kingdoms of the Holarctic. The climate of the territory is characterized by general dryness and lack of heat. The annual precipitation is 150-250 mm, the average annual temperature is -5 ... -7°C, with an amplitude of average monthly temperatures of more than 50 °C. In the lower part of the ridge, the background of vegetation cover is formed by dry steppes. The vegetation of the forest-steppe belt is a combination of meadow steppes and their petrophytic variants on the light slopes and grassy larch forests on the northern ones. The forests are severely disturbed by fires. Taiga grass forests, which previously formed a narrow strip of the forest belt above, are almost completely destroyed. The flat watersheds of the Sengilen highlands are occupied by Kobresia- communities and various tundra variants: with predominance of Betula rotundifolia, Caragana jubata, Dryas oxyodonta or lichens. Metamorphic carbonate rocks (various marbles) are well represented. Three key plots were investigated on the territory of the range: 1. Surroundings of Naryn village, 50°12 'N 95°36' E, altitude 1300-1450 m above sea level. The vegetation cover is dominated by steppes with Potentilla acaulis, Artemisia frigida, Carex duriuscula, Stipa krylovii Roshev; some plots are occupied by forests with birch, larch and spruce; willow-poplar thickets, floodplain meadows and swamps take place. 2. Naryn upiver, 50°13 'N 96°15' E, altitude 1880-2150 m above sea level. Forests from Larix sibirica and Pinus sibirica prevails in plant cover; meadows, steppes with Artemisia santolinifolia and Carex pediformis, floodplain thickets of Betula fruticosa take place. 3. Sources of the Balyktyg-Khem river, 50°19 N 96°28' E, altitude 2200-2560 m above sea level. Vegetation formed by cryophytic steppes, Kobresia- communities, alpine and subalpine meadows; different tundra variants; thickets of Caragana jubata and Rhododendron adamsii. Stony habitats (rocks, kurums and scree) are common.