Soil carbon capacity in a grassy rangeland ecosystem in North-western Iran: Implication for conservation

Abstract

Carbon dioxide is one of the most important greenhouse gases in the atmosphere. Ranges and based on carbon sequestration and soil conservation have a key role and known as dominant species in the region. In Iran, overgrazing of rangelands, during the process of soil erosion is happening that this fact resulted to decrease soil carbon. In the present study, comparative assessment of carbon sequestration capacity in the rangeland with different grazing intensity was investigated. Systematic random transect sampling with square plots was established in the region. After grinding the dried samples, organic carbon by electric furnace combustion method were measured and multiplied to the conversion ratio of organic carbon in plant biomass, carbon sequestration by total weight in both plant and finally the base case was calculated per hectare of range. Total organic carbon stock in the ecosystem, in plant biomass and soil in site 1 (low Stocking grazing) and site 2 (high Stocking grazing) was 7/5 and 4/7 ton/ha, respectively. The results of the study showed that rangelands have a major role in mitigating the effects of elevated atmospheric carbon dioxide levels on global climate change. Also, the results indicated that management practices, such as grazing, and improved plant species will be concluded to increase soil organic carbon storage in the study area. Key words: Carbon sequestration, rangeland, soil carbon capacity.