Plant flora in the rangeland of Western Saudi Arabia

摘要

During this study plant diversity in the Western Saudi Arabia including rangeland of Bahra and Hada was examined in active plant growth period, from November 2010 to April 2011. Out of 58 plant species recorded in the rangeland, 37 were found to be frequent, 15 occasional, and 6 rare based on occurring frequency range of IUCN (International Union for Conservation of Nature) classification system. The area was found to be rich in plant species belonging to poaceae family compared to other families. Plant species, occurring with frequency range below 0.5% were categorised rare, including Launaea mucronata, Cyperus conglomeratus Rottb., Trigonella stellata Forssk., Astragalus sieberi DC., Stipagrostis ciliata (Desf.) De Winter, Polygonum arenastrum Boreau. These species growing in harsh climate can be considered tolerant to heat and drought stress. The rareness of plant species and vegetation cover in Saudi Arabia may be attributed to overgrazing and some anthropogenic activities such as urbanization and landfill. This situation may further deteriorate if appropriate rangeland management, scheduled grazing, and programs for increasing awareness among people are not initiated. On basis of our study, rare plant species may need to conserve in botanical garden in their own habitat to maintain the biodiversity.