study of physiognomy and origin of plant species in sarshiv area of marivan, iran

abstract. vegetation of each region is one of the most important phenomena of nature and is the best guide to judge about the ecological sciences of that region because the plants are resistant organisms that have endured the long term conditions of all kinds of environmental conditions for a long period of time and have adapted with environmental stresses. therefore floristical investigation of each region is outmost importance for that region and it serves as a birth certification document. it also reviews geographical and floristical origins of each region which is the most effective method for managing and protecting the available genetic resources. the aim of this study was introducing flora, life form and plant chorotypes in sarshiv rangelands, west of marivan, iran. the method of sampling was random- systematic with 76 plots. floristical studies showed that there were 39 families, 116 genera and 139 plant species in this area. the most important families in this area were asteraceae (20 species), papilionaceae (fabaceae) (16 species), apiaceae (11 species) and poaceae (10 species). among all species identified in this region, one was endemic and the three other species were considered as rare. investigation of life forms based on raunkiaer method showed that there were various plants in different life form. among all of them, terophytes (35%) and chamaephytes (3%) had the highest and the lowest plant species, respectively. the review of the geographical distribution of plants in the region showed that the species belonged to different chorotypes and irano-turanian (50%) and european–siberian (1%) had the highest and the lowest plant species of the region, respectively.