Topography has direct and indirect effects on plant distribution. So knowing of relationship between vegetation and topographic factors can be effective on the estimation of species kind for ecological management in different rangeland ecosystems. Therefore, this research has been studied the topographic factors effect  on  vegetation changes. Firstly, land units map were prepared by overlaying of slope, altitude and aspect and lithology map in Gis Software. The sampling was done after identification of plant communities by plots randomly in land units. Size and number of plots were determined by minimal area method and statistical formula. Then, plant characteristics and topographic data were recorded in each community  by overlaying of plant communities and land units maps and field controlling. Also, ordination of plant communities was done by CCA and DCA. The results showed that different plant communities exhibited different correlations physiographic factors as shrubs had more correlation with altitude and aspect than grasses but those hasn’t significant relation with slope. Presence of invasive species has decreased this correlation with negative effect on ecological relationship in overgrazed communities.
Articles, citations, reports, websites, and multimedia resources focused on rangeland ecology, management, restoration, and other issues on American rangelands.