The role of semi-arid landscapes in global carbon biogeochemistry has been underestimated because of many uncertainties in the relationship between the drivers and the response fluxes of C (i.e. water influence on productivity). Strong and persistent long term changes in semi-arid systems observed from ground and space-borne measurements show unknown influences on the global carbon cycle. Our hypotheses are i) carbon dynamics and the influence of various drivers in the Sahel have changed over the past 30 years, ii) the Sahel's carbon budget has a neutral tendency and is significantly influenced by landscape management practices. In this study we analyzed a 30 years period of changes in productivity and the related influence on the carbon budget in the Sahel. We applied climate models and satellite time series to explore and to provide evidences on the variability of carbon fluxes and sinks considering various sequestration and destocking drivers—such as fire, respiration, land use change—and climate for the Sahel. In parallel an original sylvo pastoral landscape seasonal fluxes inventory denotes several sinks and sources of emissions and time length intensities Comparing modeled and observed trends with global carbon dynamics we found that the Sahel has turn from a net source to a net sink of carbon, it's contribution to the global carbon budget is however slower as compared to other biomes.