The effects of forest and rangelands covers on accumulation of soil nutrient elements in Kojour region

Two habitats of rangelands that are dominated by Stachys byzantina and Rhamnus pallasii and a forest area is dominated by oak (Quercus castaneifolia( were selected. In the plots, 36 litter and soil (0-20cm depth) samples were collected and conveyed to laboratory for measuring of the amounts of C, N, Ca, Mg, K and P elements in the litter and calculation of theirs storage in soil. The results showed that the amount of organic C and N of the litter (84.52 and 2.97%) were highest in rangelands of Rh. pallasii. Whereas the greater amounts of Ca and Mg (0.77 and 294.4%) found in forest litter, and also the higher values of K and P (0.31 and 149.0%) were observed in St. byzantina rangelands. The storages of organic C, N, Ca and Mg (1042088, 29298.3, 188396.88 and 7589.258 kg/ha, respectively) were increased in forest soils, but the St. byzantina rangeland cover improved the accumulation of P and K (18920.28 and 300.97 kg ha-1). In general, the findings of this research showed that the relationship between different plant species and the amount of accumulation of soil elements is not constant, And the positive effect of oak species on soil nutrient storage could be due to the quantity and quality of litter produced by this species compared to other species studied in this study.