Survey of plant composition and life form in Khalatposhan rangelands at Tabriz-Iran

In this study, plant species in Khalatposhan rangeland were identified. A total of 100 plant species belonging to 83 genus, and 20 families were recorded within these rangelands. Ranking of the plant families according to family dominance index (FDI) showed that Poaceae, Chenopodiaceae and Asteraceae with 99.84, 38.95, and 37.17% were respectively most important families in this area. Vegetation ranking by relative dominance (RD) index showed that bulbous bluegrass (Poa bulbosa L.), Russian thistle (Salsola kali L. subsp. Tragus (L.) Nyman), Ceratocarpus (Ceratocarpus arenarius L.), and downy brome (Bromus tectorum L.) with 65.04. 30.92, 27.62 and 18.25%, respectively were dominant species in mention rangelands. Results of this survey indicated that Khalatposhan rangelands were heavily infested with weeds, because in RD calculations, the relative contribution of weeds was higher than rangelands palatable species (263.25:400 (RD total for all species)). In order to life form vegetation, therophytes and hemicrypthophytes with 43 and 36%, respectively were abundant plants. However, chamophytes and cryptophytes with 15 and 6% of plants respectively had minimum frequency in this region. Higher frequency of therophytes in one district indicates a dry climate of their and lower frequency of cryptophytes duo to their incompatibility and intolerance to mention condition.