Floristic study of Zangelanlo watershed (Khorassan, Iran)

Zangelanlo watershed is located in Northeast of Iran, 28 km of Southeast of Daregaz between 37º13´ to 37º27´ north latitude and 59º8´ to 59º35´ east longitude. The surface area of the region is approximately 2482 ha. This area is mountainous with mean annual precipitation of about 412.7 mm. The mean maximum temperature is 20.8ºC in August and minimum temperature is -9ºC in January. The flora of the area was studied and life forms and chorotypes of the plants were identified. In this research, 64 families, 238 genera and 286 species were identified among which 8 species were endemic to Iran. The largest plant family was Asteraceae with 40 genera and 51 species and the largest genus was Astragalus of Fabaceae with 7 species. Hemicryptophytes, therophytes and cryptophytes were the most frequent life forms 114 species (39.87%), 89 species (31.12%) and 44 species (15.38%), respectively. High percentage of Hemicryptophytes indicated that the area had a cold mountain climate. Irano – Turanian plants were the most frequent chorotype of the area with 146 species (51.05%).