Abstract: Wildfire burning may have significant effects on the structure and composition of dry grasslands. A semi-arid steppe grassland, in NE Iran, 20 km far from Turkeminstan border, had experienced a summertime wildfire in 2012. We established 8 line transects at four adjacent habitats; i.e. protected without fire (POF), protected with fire (PWF), grazed without fire (GOF), and grazed with fire (GWF), during spring and summer 2013. Along each transects, 10 quadrates (1 m2) were established, in which plant composition,density and canopy cover were recorded for all species. Analysis of data was performed to measure the species diversity based on the species abundance.Calculation of species diversity, richness and evenness was performed by R and Ecological Methodology software’s. Summertime burning reduced species diversity, but the effects were more profound on the grazing rather than enclosure sites. Geophytes and Therophytes were increased, but Chamaephytes and Hemi-cryptophytes were reduced in the burnt sites; same results were found under the livestock grazing site (POF). In conclusion, although a summertime burning may cause negative impacts on the composition and diversity of dry grasslands but its effect may be partly ameliorated by the management strategies, i.e. protection of burnt sites from livestock grazing.

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