Arrange the following major Nigerian soil types in sequential order from the semi-arid northern border down to the southern Atlantic coastline.
- 1Regosols and Brown soils of the northern semi-arid zone
- 2Ferruginous tropical soils of the central savanna belt
- 3Ferrallitic red soils of the southern rainforest belt
- 4Hydromorphic and alluvial soils of the coastal delta
Answer
The correct sequential order from north to south is: Regosols and Brown soils of the northern semi-arid zone, Ferruginous tropical soils of the central savanna belt, Ferrallitic red soils of the southern rainforest belt, and Hydromorphic and alluvial soils of the coastal delta.
The geographical transect across Nigeria from north to south follows a gradient of increasing annual rainfall and vegetative cover. Starting at the northern border, thin Regosols and Brown soils predominate under semi-arid conditions. Moving south into the central Guinea savanna, Ferruginous tropical soils develop over crystalline rocks. Further south in the humid rainforest belt, high rainfall causes deep leaching to form Ferrallitic red soils. Finally, at the extreme south along the Atlantic coastline and Niger Delta, permanently wet conditions create Hydromorphic and alluvial swamp soils.
Step-by-Step Solution
Key Concept
Zonal distribution of Nigerian soils from north to south