Volume 7 Article informations Influence of climatic and geographic factors on the spatial distribution of soil organic carbon in the Tunisian dryland at Kebili oasis Hatem Ibrahim,Asma Slama , Nadhem Brahim Abstract The effect of climate variables on soil organic carbon (SOC) distribution remains unknown and poorly studied in dryland. This work presents a study of the spatial SOC distribution at continental Guettaaya oasis at Kebili governorate, so that we have an idea about the contribution of arid soils in carbon sequestration. 80 samples were collected from six stations according to a toposequence. Sampling concerned the first 30 centimeters of soil. Physicochemical analysis have identified the main characteristics of the soil. SOC rate varies from one station to another, in some stations it exceeds the rate of 3%, and generally it is abundant in surface layer compared with the underlying layers. Regarding the SOC stock at a depth of 30 cm, the highest stock is 57.7 t/ha and the lowest is 28.7 t/ha, and soil salinity varies from 2 g/l to 12 g/l. We found that SOC stock are influenced by soil salinity, bulk density, and soil texture. The SOC helps to maintain the balance of the oases ecosystem. In this oasis, the organic carbon storage exists with relatively high levels, and appears to be a carbon sink to high potential in comparison with what exists outside the oasis. Key words: Soil organic carbon, arid soils, salinity, SOC stock, Tunisian oasis.