Life Forms of The Plants in Irano-Tourani Region and The Situation of This Region in The World

The aim of this research was to identify the life form spectra in the Irano-Tourani region. Identifying these spectra can reveal the relevant life form species. By Comparison these spectra with other regions, life form spectra, the situation of this region among the other regions can be determined. It was carried out using Raunkiaer’s method to determine the life form spectra from Irano-Tourani region. It was applied using Detrended Correspondence Analysis (DCA) to identify variability among different vegetation life forms. The proportion of species in each life form class was analyzed and compared with Raunkiaer’s normal spectrum using a test. The result showed that in Irano-Tourani region the Hemicryptophytes and the Therophytes, were the main life form classes and usually the Phanerophytes were the least ones. Compared with life form spectra from other vegetation types, the Irano-Tourani region did not form a distinct group. The DCA indicated that the Mediterranean forests have more similar environmental conditions to the Irano-Tourani region.