akinsanya, olawale - The Federal University of Agriculture, Abeokuta

4.1.3: SOfL CAnONS CONTENT
Potassium (K) content reveals no significant difference in all the levels of degradation, while
Exchangeable Calcium (Ca) in the moderately degraded soil was significantly different from the severely
degraded fraction, which is higher in quantity. Exchangeable Magnesium (Mg) content was not
significantly' different between the various degradation levels. The soil sodium (Na) content for fairly
degraded fraction was
significantly higher to severely degraded soil (Table 5). Crop nutrients
requirement from sandy soils benefit more from regular and generous application of organic and
inorganic fertilizer than organic matter stock of the soil because of erosion. The depletion of fine
materials by erosion may also be the cause of the low level of organic matter.
The higher cations concentration in the fairly degraded soil suggests that there was less
leaching or erosion of nutrients from the surface soil compared to the moderately and severely
degraded site. The Sodium (Na) content was however very low that even the relatively high content
would not cause salinity problem. The acidic pH level has already indicated this.
The Coefficients of Variation (CV) suggest that soil management for replenishment of organic
matter and phosphorus, Calcium (Ca), Magnesium (Mg) and Potassium (K) will be very difficult for rice
as these did not just vary with level of soil degradation, but also with the rice variety cultivated.