A Study of Flora, Life Form, and Chorology of Plant Species in Gamasiab Region of Nahavand, ‎Hamedan province

The present study was carried out to provide a floristic list and determine the life forms and chorology of species in the Gamasiab region at a distance of 20 Km. south of Nahavand (Hamedan province). The altitudes of the region include part of the Zagros Mountain in the name of Garin Mountain or Geru, which includes several peaks. The highest peak of these heights in Hamedan province is the Yalkabud, with an altitude of 3541 meters above sea level. The area of this part is 1899 hectares. Plant specimens were collected and identified from different points of the Gamasiab region during the appropriate seasons between 1993-2021. The plant biological spectrum of this region was plotted by determining the percentage of species belonging to each biological form. On the basis of geographical distribution data of identified species and resources, the percentage of regional vegetative elements was determined. The plants identified in this area contain 51 families, 203 genera, and 311 species. Totally, this region includes 7 families of monocots, 43 families of dicots, and 1 family of pteridophytes. The largest families were Asteraceae, Lamiaceae, Fabaceae, Poaceae, Apiaceae, and Caryophyllaceae in the Gamasib region. The plants in the region were in terms of biological form, 41.1% of Hemicryptophytes, 26% of Therophytes, 13.41% of Champhytes, 13.41% of Geophytes, 3.2% of Phanorphytes, 1.6% of Parasites, and 0.96% of the Helophytes. For geographical distribution, the largest share of IranoTuranian elements (67.52%), and other species belonged to two or more geographic areas. Finally, 34 plant species were endemics of Iran.