Population Status and Natural Localities of Rhodiola rosea in Rila Mts., Bulgaria

Rhodiola rosea L., a member of Crassulaceae family, is an alpine plant that grows in specific and sensitive high-mountain habitat and is, therefore, a very suitable for studying the effect of climate change. Although the natural area of R. rosea is wide and includes most of the boreal and temperate parts of the Northern hemisphere, urgent measures for conservation of natural resources of the species are necessary. In Bulgaria, the species occurs on stony and rocky places, often on screes, in habitats near late-melting snowdrifts, which provides sufficient soil moisture (2280 - 2600 m above sea level) in Pirin, Rila and Stara planina Mts. It is protected by the Biodiversity Act of Bulgaria and is listed in the Red List of Plants in Bulgaria. The species is included in the Red Data Book of the Republic of Bulgaria (Peev, ed., 2015). According to the IUCN criteria, its threat status is Critically Endangered. This study aimed to evaluate the population size and the conservation status of six natural localities of R. rosea in Rila Mts: 1) Seven Rila Lakes; 2) Skakavitsa's waterfall; 3) Kalin Dam; 4) Rusaliite; 5) Belmeken; 6) Musala hut. The best characteristics of both population size and conservation status were recorded in the localities situated in remote and hardly accessible areas with limited or no tourists' access. Based on thorough evaluations of trade levels and trends compared to population sizes, R. rosea must be considered to face serious threats from overexploitation and growing international trade due to its increasing use in herbal medicine.