Characterization and classification of the soils of a toposequence at Gbagba, Kwara state, Nigeria.

Abstract

The morphological, chemical and physical characteristics of the soils of a toposequence developed over banded gneiss at Gbagba, in Kwara State were studied. The soils are generally sandy on the surface with high gravel coment in the sub-surface horizons. Bulk density values ranged from 1.01 to 1.65g/cm3 and are generally higher in the coarser textured soils. The soils are slightly acidic, the base saturation and cation. exchange capacity values are moderate, white organic carbon values  are low. It was only pedon I that exhiblted pedogenic clay. The opH values ranged between 1.00 and 1.27. The soils are classified according to the USDA Soil Survey Staff as Plinthic Dystrusta(( (Pedon I), Typic Plinthustalf (Pedon 2) and Psammentic Alaquept ( Pedon 3). They are also classified as Dystric Plinthisols (Pedons I and 2) and Dystric Fluvisol (Pedon 3)' of the FAO/UNESCO Revised legend of the Soil Map of the World..