<p>Enhancing the capacity of agricultural soils to resist soil degradation and to mitigate climate change requires long-term assessments of land-use systems. Such long-term evaluations, particularly regarding low-input livestock systems, are limited. This study evaluated the impact of long-term land-use practices, condensed tannins (CT) and soil nutrient status on carbon cycling in arable and permanent systems of a tropical Savannah. Soil samples were taken (0–30 cm depth) from arable crop fields, grazed-seeded grassland, cut-use permanent crops and native grassland. Soil organic carbon (SOC) stocks ranged from 19.9 to 36.8 Mg SOC ha<sup>−1</sup> (mean ± sd = 32.9 ± 0.2 Mg ha<sup>−1</sup>). SOC stocks were lower for grazed-seeded grassland relative to cut-use grass, legume trees and shrubs. Within sown systems, nitrogen availability seemed to be the most critical factor that determines the fate of the SOC stocks, with soil nitrogen (N) concentration and the SOC being highly correlated (<i>r</i> = 0.90; <i>p</i> < 0.001). Accordingly, while converting the native grassland to grazed pastures resulted in mean annual losses of 0.11 Mg C ha<sup>−1</sup> (<i>p</i> < 0.05), the conversion to woody legumes resulted in slight (0.03 Mg C ha<sup>−1</sup>, <i>ns</i>) increments. In total, CT, N, P, K and pH (with interaction terms) explained 92 % of variations in the long-term changes of SOC stocks. The regression model showed that improved soil fertility management and the use of tannin-rich plants could promote SOC storage in the Savannah ecological region in the long-run. Our study suggests the cultivation of legume tree/shrub forage species as an environmentally sustainable land-use option to mitigate agricultural CO<sub>2</sub> emissions from low-input livestock systems in the grasslands of southern Ghana.</p>