flora, life form and chorology of winter and rural range plants in the northern khorasan province, iran

floristic studies are fundamental for the applied sciences such as rangelandmanagement and conservation. unique ecological and climatic conditions in the northernkhorasan province (nkp) make it a remarkable habitat for the floristic studies. plant specieswere collected from 50 field sites, representing major habitats of winter and rural rangelands.surveys were conducted during active growth periods in 2007 and 2008. plant species wereidentified and their chorology and life form determined through laboratory examinations andby using reference books. floristic surveys resulted in identification of 534 plant species,belonged to 315 genus and 68 families. asteraceae, poaceae and fabaceae were respectivelythe most abundant plant families. among the life forms, hemicryptophytes, therophytes,chamaephytes, phanerophytes and geophytes included 45, 32, 9, 7 and 7% of the totalspecies, respectively. irano-turanian was the most dominant (65%) chorotypes. thedominance of hemicryptophytes and therophytes, as well as vast distribution ofchamaephytes, can be referred to the simultaneous effects of climate fluctuations andlivestock grazing on the flora of winter and rural rangelands in nkp.