Characterization and Classification of Soils on a Toposequence in Afikpo, Southeastern Nigeria: A Geographical Information System (GIS) Approach

Abstract

This study was carried out in 2008 on a toposequence located at Afikpo, Southeastern Nigeria and aimed at characterizing and classifying soils of the area for optimal utilization using a transect technique. Three pedons were dug on soils of the crest, midslope and footslpe at an inter-pedal distance of about 100 m. At the crest, (pedon A) colour ranged from grayish red (2.5YR 5/2) moist to dull orange (7.5 YR 7/4) moist; Pedon B (midslope), colour matrix graded from light gray (10 YR 7/1) moist to light yellowish orange (10 YR 7/6) moist while at the Pedon C (Footslope), colour graded from dull yellow orange (10 YR 7/3) moist to dull orange (5 YR 7/4) moist. Soils were sandy and Silt/clay ratios were low and increased down the slope. Organic matter, Total N and Available P were all low and deceased down the profile. Base saturation values were 25.4, 27.0 and 54.75% for crest, mid and foot slopes, respectively. However, in all the physiographic views; OM, TN, P and Base saturation indicated high variability (HV) except at the footslope where OM and Base saturation varied moderately (MV). Pedons A and B were classified as Typic Kandiudults (Plinthic Acrisol) while Pedon C as Typic Kandiudalf (Albic Luvisol).