Soil, forest and atmosphere are potential carbon sinker in the terrestrial ecosystem, of which the share of soil is more than that of forest and atmosphere. In Ethiopia very few studies have been conducted on forest soil organic carbon storage capacity. The purposes of this study was to determine organic carbon storage capacity of Kafa forest soil and to generate relevant information for stakeholders on forest soil organic carbon storing capacity that helps them for land management decisions

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... carbon trading. To achieve these goals, a representative forest land was selected in Bita district and five successive soil profiles were excavated at different slope positions of the toposequence. Soil samples were collected from each horizon of the soil profiles to determine soil carbon concentration and bulk density. Organic carbon storage (t ha ) capacity of each 1 horizon was obtained by multiplying the bulk density, organic carbon concentration and horizon thickness of the soil. The amount of organic carbon stored (t ha ) in each profile was obtained by summing up organic 1 carbon stored in the successive horizons of the respective profiles. Multiple linear regression model was employed to describe the effects of independent variables on dependent variables and Pearson's correlations analysis was used to determine the relationship between dependent and independent variables. Regression analysis revealed a unit rise in soil organic carbon concentration, bulk density and sampling depth rises soil organic carbon stock by 5.47, 1.53 and 25.64 t ha , respectively. Soil organic carbon storage capacity was 1 significantly (P < 0.0001) affected by organic carbon concentration and sampling depth. Besides, correlation analysis indicated, the amount of organic carbon stored in the soil has a positive relationship with organic carbon concentration and bulk density. The quantity of organic carbon stored in the soil was 639.64±286.10 t ha . The quantity of organic carbon stored in the soil has been governed by soil organic carbon 1 concentration and bulk density. Thus, soil organic carbon concentration and bulk density improvement are the most important management interventions to increase soil organic carbon storage capacity. Therefore, stakeholders should focus on management activities that improve soil organic carbon concentration and bulk density to boost carbon stock capacity of the soil.