Evaluation of Enclosure Effects on Soil Carbon Storage (Case Study: Rangeland of Shahtappeh-Chah Mahmood and Chiro in Semnan Province)

Livestock grazing is one of the most important kinds of land usage that has a high potential to decrease or increase carbon storage in rangeland ecosystem. this research was investigated the effects of enclosure on soil carbon storage in a rangeland with dominant plants of artemisia aucheri. hence, two rangelands of enclosure (shahtappeh-chah mahmood) and no enclosure (chiro) were chosen in semnan province, iran. for soil sampling, 20 plots of 1x1 m2 along with two vertical transects with 100 m length were used in each region. then, two profiles were dug in 0-15 and 15-30 cm depths in soil of baseline and inter-path of plants in each plot. data were collected for ph, ec, caco3, saturation moisture, soil texture, organic carbon (oc%) and s organic matter (om%), soil bulk density and soil carbon storage and the mean was compared by t-test. the results showed that there was a significant difference (p < 0.05) between oc% and om% of baseline in enclosure and no enclosure rangeland. soil oc% and om% in baseline in the first depth was more than the second depth in two study areas. there was a significant difference (p < 0.05) between soil oc% and om% in baseline and inter-path of plants in two depths of enclosure and no enclosure rangelands. soil bulk density (gr/ha) in baseline and inter-path of plants in 15-30 cm was more than 0-15 cm. in enclosure and no enclosure rangelands, grazing had no significant effects on soil organic carbon storage of baseline in each depth. so, the total carbon in 0-30 cm in each region was 47.46 and 40.85 ton/ha, respectively. there was a significant difference between carbon storage of baseline and inter-path of plants (p < 0.05) in two depths in enclosure and control rangelands. it was concluded that higher carbon sequestration occurs in the soil, the soil biological and mechanical activities can increase.