Introduction to the Flora, Life Form and Chorology of the Avrin Mountains Rangelands in Khoy, West Azerbaijan

Rangeland habitats of the Avrin Mountains, Khoy are representing a wide range of mountainous vegetations in terms of climate, soil, topography and plant cover in Western Iran. In this regard, plant species were sampled periodically during the 2013–2014 period, and identified using the existing floral references. Their life-forms were determined based on the Raunkiaer’s classification and rare and endangered species of the area were recognized based on the criteria of Association for Protection of Genetic Resources. Moreover, their geographical distribution was determined on the basis of classification of vegation regions. Floristic study of the collected vegetation resulted in the identification of 287 species belonging to 52 families and 172 genera of vascular plants. The largest plant family is Asteraceae with 46 species and the largest genus is Astragalus of Fabaceae with 19 species. The diagram of plant life formed by the Raunkiaer method showed that the dominant life forms of the area were hemicryptophytes with 47% and geophytes (Cryptophytes) with 18%, whose high percentage demonstrate the cold climate and mountainous region. Cryptophytes(18%), chamaephytes (16%), therophytes (15%) and phanerophytes (4%) have the less degrees of abundance. The geographical distribution of plants showed that 48% of species belong to the Irano–Turanian zone. The distribution of 7% of the flora in the region is multi-regional, 22.5% are Irano-Turanian and Euro-Siberian, 2.5% are Irano-Turanian and Mediterranean, 0.7 % are Euro-Siberian and Mediterranean, 4.5% are Euro-Siberian, and 1.3% are Mediterranean-related. Among the identified species, 2.5% have cosmopolitan distribution and 11% are endemic to Iran. According to the Protection Association of Genetic Resources, 14 species are classified as rare and endangered plant species.