ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 82 Number 4
Profile distribution of soil structural properties of some inland valley soils of central Cross River State, south-eastern Nigeria. (307)
Inland valley soils (i.e., valley bottoms and minor flood plains which are seasonally submerged for part or all of the year) are prime soils with problems of less efficient utilization compared to their fertility potentials, and dearth of soil structural information particularly in the tropics. The Cross River State in south-eastern Nigeria has 38 000 ha of inland valleys. A total of six profiles were sampled in this study to evaluate the distribution of soil structural properties with a view to assessing its agricultural implications. Apart from few cases of crumb, angular blocky, and prismatic structures, the surface horizons were principally made of sub-angular blocky structures. The structures of the upper part of the subsoil horizons were a mixture of sub-angular blocky and prismatic whereas that of the lower part was mainly prismatic. Textures ranged from sandy-loam to clay but the latter predominated. The percentage clay increased with increase in soil depth. Particle size distribution showed the soils will be quite suitable for paddy rice production. All the sampled soils had no problems of excessively high bulk densities, hence, would not be expected to impede root penetration and development. The differences in the mean particle density were quite minimal. Particle density was generally less than the average for soils elsewhere, which may be taken as 2.65 g cm-3.
Keywords: Inland valley soils; Structure; Particle size; Porosity; South-eastern Nigeria