forest roads construction as one of the factors contributing to ecological changes can affect the diversity and composition of species on the road edge area. This study examines the biodiversity of herbaceous species and the establishment of tree regeneration at various distances from the edge of the road with the aim of investigating the impact of the road. For this purpose, macroplots with dimension of 100 m2 (20 x 5 m) in six intervals of 0, 5, 10, 25, 50 and 100 meters, in both side of road was designed and inside them, 2 × 2 m microplots for sampling of herbaceous spices and tree species regeneration was done too. In order to study the diversity, the Simpson and Shannon-Weiner index, the species richness index (s) and Pylo's uniformity index were used. The results showed that there were no significant differences between the index of herbaceous diversity and regeneration of trees on the top and bottom parts of roads, and the most important factor is the distance. As the distance from the road increases, the biodiversity, richness and uniformity of the herbaceousplants decreases but the regeneration of trees increases. Also, the richness index indicates that herbaceous species on the edges of the road (10-0 m) and tree regeneration in the inner parts of forest are the major. Based on the results, among environmental factors and soil parameters, light condition is the main determinant factor of the establishment of species, as well as the frequency and distribution of species in the distance between roads to the forest. As a result, minimizing road density is necessary to maintain the diversity and composition of forest species for the sustainability of forest resources.
