Amélioration du Stock de Carbone Organique des Sols Ferrugineux Tropicaux Sous Pratique de la Régénération Naturelle Assistée en Zone Sahélienne du Niger

In the context of the continued decline in the fertility of cultivated tropical ferruginous soils, farmers in most of Niger's agricultural zone are practising FMNR to cope with soil degradation and improve their agricultural production. The present study, conducted in one of the country's main growing and generalized FMNR regions, aims to assess the effects of FMNR on cultivated tropical ferruginous SCOS in order to appreciate its contribution. It consisted of taking soil samples from a depth of 0-20 cm using an auger and a cylinder to determine the soil organic carbon content and bulk density respectively. The results show that FMNR influences SOC levels because statistical analyses revealed significant differences between the crowned and non-crowned areas of trees and shrubs from FMNR. It also appears that the age of the NAS does not have a significant effect on SCOS rates. However, it is largely influenced by the age of trees and shrubs from the FMNR, the density of woody plants, the types of species and agricultural activities. Indeed, over a depth of 0-20 cm, the SCOS rates vary from 51.09 t C.ha-1 in Dan Saga to 61.33 t C.ha-1 in Boussaragui. In addition, the results reveal that wind contributes to the spatial distribution of SCOS. This study demonstrates once again the enormous potential of the practice of FMNR in carbon sequestration and the improvement of the fertility of tropical ferruginous soils in the context of climate change.