Characterization of selected valley bottom soils in University of Ibadan, Ibadan Nigeria

Abstract

A Study was conducted to characterize and determine the potentials of valley bottom soils at University of Ibadan, South Western Nigeria. Soil survey was carried out using rigid grid method where three soil types were identified as Jago series, Matako series and Matako series “browner variation”, soil samples were collected from genetic horizons and were subjected to laboratory analysis using standard procedure. The soils were characterized based on their physical and chemical properties. The soil texture ranged from sandy loam to loamy sand. Saturated hydraulic conductivity (Ks) in Jago series ranged from 10.00 to 18.20 cm/hr; for Matako series it ranged from 16.00 to 22.10 cm/hr and for Matako series (browner variation) it was from 13.31 to 28.33 cm/hr. Bulk density for Jago and Matako soil series, increased with soil depth while for Matako series “browner variation” it fluctuates across the profile. Jago soil series showed neutral (6.58) pH (H₂O), while Matako series had 6.36 and Matako (browner variation) had 6.48 which are slightly acidic. Organic carbon (OC) content, were all high in the series with Jago having (8.22 g/kg) while Matako series had (16.36 g/kg) and Matako (browner variation) had (17.13 g/kg). Total Nitrogen (TN) content was low for all soil series (0.50 g/kg) for both Jago and matako series, Matako series (browner variation) had (0.95g/kg). Available Phosphorous (P), Potassium (K), and Base Saturation (BS), for Jago series had values of 27.5 mg/kg, 1.05 cmol/kg, 98.85 %; Matako series had 26.80 mg/kg, 0.7 cmol/kg, 98.82 %, and Matako series (browner variation) had 27.06 mg/kg, 1.20 cmol/kg, 98.65 %, respectively. The soils were generally very deep with no evidence of rock outcrops and are imperfectly to poorly drained due to the high water table, therefore, there is need for good drainage to harness the potentials and utilization for crop production and other uses.