Major characteristics and classification of soils in duduguru, obi lga of Nasarawa State, Nigeria

Three pedons were exposed, one in each three soil units (DD1, DD2 and DD3) and soil samples were collected from different soil horizons. Soils in pedons DD1 and DD2 were deep (100–115 cm) while DD3 was shallow (48 cm), surface soil color ranged from dark brown (7.5YR 5/2 dry, 7.5YR 2.5/0 moist) in DD1, dark brown (7.5YR 5/8 dry, 10YR 5/2 moist) in DD2 and yellowish brown (10YR 6/3 dry, 10YR 4/4 moist) in DD3. Soil textural classes ranged from sandy loam to sandy clay loam and bulk densities were high (1.54–1.94 g cm⁻³). Soil reaction was strongly acid to moderately acid (pH 5.50–6.98), organic carbon contents were moderate (14.6–18.7gkg⁻¹), total nitrogen (TN) medium (21–40 g kg⁻¹), CEC moderate (6.26–9.26 cmol kg⁻¹). Soils of three pedons had high base saturation (88.1–94.6%); moderate in Ca and Mg contents, low in K and Na content (0.16–0.19 cmol kg⁻¹). Soils were classified as Typic Haplusterts, Typic Plinthaqualfs and Typic Plinthustalfs according to USDA classification and as Haplic Vertisols (Eutric), Plinthic Acrisols (Eutric, oxyaquic) and Haplic Plinthosols (Eutric) according to World Reference Base for Soil Resource (WRB).