Spatial dependence of some physical properties of a typic plithaqaualf on the basement complex in southwestern Nigeria

Knowledge of soil physical and chemical properties is a key to making agronomic and environmental decisions. The objective of this study was to assess the extent of spatial dependence and spatial structure of some soil physical properties and implications on pedogenesis and management in the basement complex soils of southwestern Nigeria. Surface soil (0 – 15cm) samples were collected at 10 m2 rigid grid intervals in a 0.5 hectare plot under fallow along Parry road in University of Ibadan. Classical statistics and geostatistics were adopted in analysis of data. Among the nine measured soil physical properties, sand, coarse sand and bulk density were least variable with coefficient of variation (CV) 1535%). The nugget to sill ratio showed that clay (12.5%), silt (9.9%), fine sand (17.0%), silt + clay (5.4%), SCR (25.7%), bulk density (18.1%) and hydraulic conductivity (12.2%) were strongly spatially dependent, while total sand (40.4%) and coarse sand (29.2%) contents were moderately spatially dependent indicating intrinsic variation attributable to soil particle size and mineralogy. Pearson correlation coefficients of the semivariances of the soil physical properties indicated that there were very few significant (