Effect of different harvesting intensities on forage production and vitality of stipa arabica at Isfahan Soh site

Appropriate utilization of plant species in rangelands is one of the principles of sustainable production in rangeland ecosystems that leads to continuous and economic utilization of rangelands. In order to achieve stability and continuity of production in steppe rangeland, this study was performed to investigate the effect of different harvesting intensities on forage production and vitality of Stipa arabica at Isfahan Soh site, during 2007 to 2010. Treatments in each block were included four grazing intensities of 25, 50 and 75% and control (no harvest). In each treatment, 10 individuals of species were used as replications evaluated on each of the dependent variables. A factorial experiment in a completely randomized design with ten replications and four years was used to analyze the data. Data analysis was performed by SAS software. Results showed that forage production of Stipa arabica did not differ statistically in response to different harvesting intensities, and up to 75 percent of the species could be harvested, but heavy harvesting intensity decreased the vigor and vitality of the species during the examined years. Harvesting intensities were significant at 1% level of probability and production rate decreased gradually over the 4 years. According to the results, a harvesting intensity of 50% is recommended for Stipa arabica in the region so that health and vitality of this species is preserved during the harvesting years.