Abstract

Fire is one of the most important ecological factors in semi-steppe rangelands directing plant community composition, diversity, structure and function of ecosystems. Our primary aim was to examine the effect of fire on plant community composition, diversity, plant species restoration and animal selectivity in semi-steppe rangeland in Karsanak region, Chaharmahal & Bakhtiari province in years 2005, 2008 and 2009. To do so, sampling was performed in burned and control areas using quadrates (2*2 m) installed along a 200 meter transect and plant cover, number of restored and grazed plant species estimated within them. There was a significant difference in plant community composition and diversity between the burdened and control areas in years 2008 and 2009. However, no significant difference was observed for year 2005. This may confirm that a four year period is needed to restore vegetation after fire. Most of graminoids species such as Agropron repense and Bromus tomentellus were restored by 90 and 80 percent respectively whereas, shrub species such as Astragalus adcendense and Astragalus susianus restored by 60 and 40 percent just one year after fire. The results also showed that animals selected burdened areas significantly more than controls in areas burned in 2008 and 2009, while the selectivity was the same for control and burned areas in 2005.