Caractéristiques des sols sous savane et sous forêt naturelle sur le plateau des Batéké en République Démocratique du Congo

Soil Characteristics Under Savanna and Natural Forest on the Bateke Plateau in the Democratic Republic of Congo. One of the major constraints for the natural replenishment of the fertility of savanna sandy soils is the continual shortening of fallow in the traditional slash and burn system. On the Bateke plateau, agroforestry appeared as one of the alternative systems to cope with soils poverty. This study is a preliminary assessment of soil nutrient contents up to 120 cm deep, under natural savanna and forest, developed on the same parent material with kaolinite as dominant clay and to assess the opportunity to support agroforestry. Ninety composite soil samples were collected and analyzed. Mean comparisons and discriminate analyses were used for statistical purpose. The result of statistical analysis did not show significant differences in soil composition. The high yields in shifting cultivation after forest clearance could be explained by the contribution of organic matter, due to large quantities of ashes that improves the nutrient balances in the soil. Agroforestry is then justified not only because of its high supply of organic matter, but also because it can really shorten the fallow duration.