Assessment of Selected Morphological, Physical and Chemical Characteristics of Upland Pedons in Eastern Kogi State, Nigeria

This research aimed at assessing the morphological and physico-chemical characteristics of upland soils in Kogi State of Nigeria. The research adopted a free soil survey technique whereby four pedons (Okura-P, Egume-P, Acharu-P and Ankpa-P) represented by four (4) soil profile pits were used for the study. Soil samples were carefully collected from delineated soil horizons for laboratory physical and chemical analyses. The morphological descriptions of the soil profiles followed the standard of the United States Department of Agriculture (USDA). The results showed dominant dull reddish brown (2.5YR4/4, 5YR4/3) in the surface and reddish brown, (2.5YR4/6), a reddish brown (2.5YR 5/8, 5YR4/8) and red (10R4/8) in the subsurface soils, while the structure of the subsurface soils varied mainly between sub-angular and angular blocky structure. Sand fraction of the soils is mostly coarse with ranges of 500 to 670 g kg-1 at the surface and 330 to 660 g kg-1 in the sub-surface soils. The bulk density of the soils generally increased down the profiles with a mean sub-surface value of 1.82 g cm-3, being higher than the surface mean value (1.74 g cm-3). The pH value of the soils is higher at the surface soils with a mean value of 5.3 than in the sub-surface soils with a mean value of 4.9, while the percentage base saturation and aluminium saturation percentage had surface mean values of 30 and 4% and subsurface mean value of 35and 23% respectively. The test for coefficient of variation showed varying percentages across the pedons with saturated hydraulic conductivity scoring the highest (92%) in the subsurface soils. The fertility of these soils could be improved with addition of organic matter enrichment sources.