Volume 8 Article informations Distribution of organic carbon stocks in cambisol under two different crops in semi-arid Tunisian climate Jamel Jaouadi , Nadhem Brahim , Abdessatar Hatira , Hamouda Aichi , Habib Ben Hassine Abstract The present study consists of an analysis of the organic matter content of the soil samples taken from two plots with different crops or a study site in north Tunisia, a first plot of which the soil is cultivated with Sorghum (Sorghum bicolor) and in the second plot, the soil is grown with parcel in cereal and market gardening. In the southern Mediterranean zone under semi-arid climate, the pressure of increased climate change induces a change in soil qualities and their potential for production. At the level of its zones, the study of the dynamics of Organic Matter and the associated carbon of soils is subject to certain constraints. In addition, there is the possibility of studying biological and/or abiotic phenomena that control the dynamics and stability of organic matter in soils. On the other hand, deep carbon turnover is particularly slow. The results show that under sorghum cultivation a good improvement of the organic stock is manifested by a high organic carbon content at the surface layer level 0-20 cm with 1.99% in comparison with the cereal plot, which has a maximum content of 0.97 %. Respectively, a clear improvement for bulk densities with 1.26 and 1.28 g.cm-3 . On the whole profile and 1 meter deep the stock under sorghum is significantly higher, it is of the order of 2.5 times, with a value of 117.47 t/ha against 45.23t/ha for soil under cereals. Key words: Soil organic carbon, Cambisol, Carbon sequestration, Sorghum/cereals culture, Tunisia