Determining specific species and the species contribution in the similarity between soil seed bank and standing vegetation (Case study: Lazour rangeland- Firouzkooh)

Determining the potential of soil seed bank and its specific species is important for conservation goals and vegetation restoration of rangelands. In this study, the characteristics of soil seed bank and standing vegetation in Lazour mountain rangeland were investigated in order to estimate the rehabilitation ability of the study area in case of possible disturbances. In order to determine the percentage of similarity between the floristic composition of the soil seed bank and vegetation on the ground, display the distribution pattern of species, determine the species contribution in the similarity and determine the specific species of each group, respectively Sorenson index, nMDS ordination analysis, ANOSIM and SIMPER tests and analysis of index species was used. The results showed that in the soil seed bank, therophytes and annual herbaceous as well as the Poaceae family had the highest percentage of species. Considering the presence of all soil seed bank species in the vegetation list of the study area, Sorenson similarity index was estimated to be 67%. Bromus tomentellus played the highest role in creating a similarity matrix between standing vegetation and soil seed bank. Poa bulbosa with at least 71 seeds per square meter was significantly considered one of the valuable species at the depth of 5-10 cm soil seed bank. Also, important species with conservation value from the perspective of rangeland sciences such as Bromus tomentellus, Thymus pubescens, Stipa holosericea, Lactuca orientalis, Festuca ovina and Astragalus lilacinus with at least 913, 269, 234, 120, 57 and 14 seeds per square meter of soil, respectively, will be able to restore Lazour rangeland in case of destruction of vegetation on the ground.