So far, little is known about the influence of soil properties on forest structure, species composition and carbon fluxes in the Congo Basin. To fill this knowledge gap, the COBARCHIVES project aims to (i) do a thorough analysis of all current available soil data in the Congo Basin, (ii) enlarge the database by taking new soil samples and (iii) investigate the effects of nutrient depletion on the productivity of repeatedly burned pioneer forests. The first two objectives focus on the relation between soils and forest dynamics in old growth primary forests, while the third one addresses the effect of increasing agricultural pressure on soil parameters and consequently ecosystem functioning. Combined, these research efforts will help us gain insights into the influence of soils on the future of forests and agriculture in the Congo Basin.