Physico-chemical properties of some limestone soils in Southeastern Nigeria

The morphological, physical and chemical properties of selected limestone soils in the forest zones of Cross River State, Nigeria, were studied. Four profile pits were dug, described and sampled for analysis and interpretation. The results showed that the textures of the soils are sandy loam to sandy clay loam with more gravels at the crest. The bulk density and particle density ranged from 1.75 – 1.94 g/cm3 and 2.50 – 2.70 g/cm3 respectively. The pH ranged from 4.8 – 7.1 with the highest values obtained in the surface soils. The values for organic carbon and total N are low, 1.20 – 2.44% and 0.14 – 0.25% respectively. The available P contents ranged from 8.37 – 53.25 mg/kg. Exchangeable Ca and Mg contents are medium to high (1.2 – 20.0 cmol/kg and 0.6 – 3.0 cmol/kg respectively). Exchangeable K contents are medium (0.18 – 0.50 cmol/kg), while those of Na are low (0.07 – 0.11 cmol/kg). The CEC and base saturation are rated medium to high, ranging from 25.50 – 55.56 cmol/kg and 43.19 – 92.63% respectively. Nigerian Journal of Soil Science Vol. 15 2005: 81-8