【摘 要】
：
A study was conducted to identify plant species,diversity,life form and relevant species to Mediterranean climate,Irano-Torunian and Sahara-Sindian in Postband
【机 构】
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Department of Forestry
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A study was conducted to identify plant species,diversity,life form and relevant species to Mediterranean climate,Irano-Torunian and Sahara-Sindian in Postband region (N 27°584"(28°216",E 53°1734"(53°2230"). In total,95 species belonging to 29 families and 69 genera of flora were surveyed and identified from December 2006 to June 2008. Composite and Gramineae were important families in terms of species frequency. According to Raunkiaers system and using tests,the life-form spectrum showed that therophytes accounted for 47% of all species,and hemicryptophytes for 31%,phanerophytes for 12%,chamaeophyte for 7%,and cryptophytes for 3%. In geographical distribution,29% species with the most frequency belonged to Irano-Torunian region. Results show that therophytes were more than normal spectrum and phaneropytes were less than normal spectrum,which was in agreement with data obtained in arid climate.
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