Soil fertility in the different occupation units of the Kadzel sub-watershed (Lake Chad); Niger

Résumé

The Kadzel subwatershed is located in an arid to semi-arid zone characterized by several environmental constraints (drought, soil degradation, flooding, and excessive logging). The objective of this study is to assess the influence of soil physicochemical characteristics on the woody vegetation of different land use units. A total of 23 composite soil samples were collected from 7 land use units at a depth of 0 to 20 cm. Physicochemical analyses were performed in the laboratory on the composite soil samples from the different land use units. ANOVA, CFA, and correlation statistical analyses were performed to highlight the differences and relationships between soil fertility factors depending on the land use units. Soil pH, conductivity, exchangeable bases, cation exchange capacity, organic matter, phosphorus, and carbon content differ significantly (P=0.0023) from one land-use unit to another. Low availability of soil fertility elements constitutes the major constraints for vegetation regeneration in the Kadzel sub-watershed.