Characterization of physico-chemical properties and micronutrients status of soil developed on Anantigha Coastal Marine Sediment in Calabar

Abstract

A study was carried out to characterize the physico-chemical properties and micronutrients status of soil developed on Anantigha coastal marine sediment in Calabar. Four profile pits were dug along the coastal area and soil samples taken from identified horizons were subjected to laboratory routine analysis. The data obtained were subjected to one-way Analysis of variance (ANOVA). The predominant colours observed for the study were mostly; dark greys (2.5YR 4/1) and black (10YR 2/1). The soil were massive in structure and has very sticky and very plastic in consistence and the boundary observed was mostly diffuse smooth and clear smooth. Percent sand fraction was the dominant particle size fraction except in profile 4. Soil in profile 1 was made up of sandy loam, silt loam loamy sand, loam and sandy clay loam, while soil in profiles 2, 3 and 4 were predominantly sandy loam, sandy clay loam and silt loam, respectively. Soil pH measured in water and calcium chloride were very strongly acidic and increases with horizon depth with pH mean values of 2.5 in H₂O and 2.2 in CaCl₂ for surface soil and 2.7 in H₂O and 2.4 in CaCl₂ for sub- surface soils. The organic carbon and organic matter content of the surface soils were high and those of the subsurface soils were moderate. The mean electrical conductivity was 2.0 and 2.3 dsm^-1for surface and subsurface soils respectively. The exchangeable cations (Ca²⁺, Mg²⁺, K⁺ and Na⁺) were moderate to high in both surface and subsurface soils. The exchangeable acidity (Al³⁺ and H⁺) were high. CEC was low in surface soils and high in subsurface soils. Base saturation in both surface and subsurface soils was below 50 %. The results obtained for available micronutrients showed that the mean values for Zn, Cu, Fe and Mn were 1.43, 0.92, 134.65 and 5.05 mg/kg for surface soil and 1.89, 1.89, 121.29 and 1.48 mg/kg for subsurface soil. Zn and Cu were generally “low” to “medium” in all the horizons of the pedons while Fe and Mn values were “high”. Agronomic practice such as liming that will raise soil pH is recommended so that levels of nutrients that are below the critical levels will be made available in the soil.

Keywords: Morphology, micronutrients, physicochemical, marine sediment