Assessment of Soil Physico-Chemical Properties on a Toposequence of an Erosion Site in Ikeduru, Southeastern Nigeria

Abstract

The study was carried out to assess soil physic-chemical properties of an erosion site in Ikeduru, Imo State Nigeria, which has experienced land degradation over the years. Three profile pits were dug, described and samples collected for the physico-chemical laboratory analysis. Data obtained were analyzed using Genstat Discovery, Edition 4 for a CRD experiment. The outcome shows soils was deep, fine weak, dark brown, brown, red and dark reddish brown in the Munsell colour code. An LSD, a correlation at 5% probability level was used to separate the means significantly. Correlation investigation was carried out to explain relationships among selected physico-chemical properties of the studied soil. The particle size distribution indicated high sand content and low clay content in the three profiles selected with SCL as dominating textural class, except for 1.85 g cm-3 bulk density which was observed to be safe in all the profile pits examined, the silt ─ clay ratio was low (<1), except at the surface soil in the foot-slope (1.09). Soil pH (KCl) was moderately acidic at the summit. The organic matter had significant positive correlations with TN (r = 0.99***), Ca (r = 0.85**), Mg (r = 0.59*), K (r = 0.61*) and ECEC (r = 0.74**). Phosphorus maintained significant positive relationships with all basic cations with correlation coefficients that ranged from 0.51* for K to 0.59* for Ca. Total exchangeable acidity had a significant (P<0.001) negative relationship with %BS (r =-0.98***). It has been seen that the main causes of erosion are unprofessional land use forms.