Species composition and seed density of soil seed bank in mountain grassland of north Alborz

In natural ecosystems، a part of species composition is stored in the soil seed bank as a community of living seeds. Identifying these species pools is important for vegetation conservation and restoration. This study aimed to identify the seed bank size and composition in a part of mountain grassland of Alborz in Mazandaran province. Seed bank was sampled from two soil depths (0-5 and 5-10 cm) and then emerging seedlings were identified and counted in a glasshouse. Results showed that 49 species were in the soil seed bank، of which only 30 species were common between the soil seed bank and standing vegetation. The most abundant species in the seed bank were Carex sp.، Cynodon dactylon، Stachys byzanthina، Dactylis glomerata and Stellaria media comprising 50% of the total. According to plant functional groups، Gramineae، Cyperaceae، Labiatae، hemi-cryptophytes، forbs and perennials were dominant in the seed bank. The majority of seedlings originated from the upper soil layer (0-5 cm)، with 70% of the total germination. Moreover، the upper soil layer significantly had greater species richness and diversity than that in lower soil depth. Also، greater species richness and diversity was found in above-ground vegetation than that in the soil seed bank.