Bryophyte flora of "Naratsaz tract" natural monument (Republic of Bashkortostan, the Bashkir Cis-Urals)

The bryophyte flora of protected area - natural monument “Naratsaz Tract” (the Republic of Bashkortostan, the Southern Ural region) was investigated. The vegetation of study area is complex of wet woodlands, calcareous fens and heterotrophic mires characterized by a high level of phytocoenotic and species diversity. On the periphery of Naratsaz Mire, the wet black alder and birch woodlands are common. The western part of study area is located in the floodplain of Bir' River and covered by grey alder forest. In the central part the mire is heterotrophic and formed by complex of oligotrophic, mesotrophic and eutrophic communities. Oligotrophic and mesotrophic pine-birch stands with dominance of cranberry and boreal mosses, or Sphagnum spp. +Ledum grow at the raised ridges that are surrounded by minerotrophic fens with Phragmites australis, Cladium mariscus, Schoenus ferrugineus, Triglochin palustre, mosses Campylium stellatum and Scorpidium cossonii. Also, there are the small lakes with calcareous Сhara algae and base-rich fens between which hummocks formed by Sphagnum fuscum and other oligotrophic vascular plants and mosses are located. High diversity of plant communities growing in habitats with different trophic and acidity conditions causes a richness of bryophytes. In total, 80 species of bryophytes (59 mosses and 21 liverworts) are revealed. Analyses of geographic distribution of bryophytes showed that liverwort flora have high proportion of boreal (47.6 %), boreo-nemoral (23.8 %) and nemoral (14.2 %) species. Moss flora is represented mostly by multizonal (47.5 %) and arctic-boreo-alpine (37.3 %) species. Among rare species that are known from 1-3 localities in the Southern Urals are Cephaloziella elachista, Liochlaena subulata, Riccardia latifrons and Paludella squarrosa (the last species is included in Red Data Book of Bashkortostan). The calcareous minerotrophic fens forming the core of Naratsaz Mire vegetation complex are locally rare plant communities of high conservation status in many countries. About one-third of surveyed bryophyte flora are formed by arctic-boreo-alpine and boreal species that grow in Bashkortostan on the southern border of range. Among them there are many habitat specialists of calcareous mires, declining in many regions due to human impact.