inputs to the soil are primarily from the application of fertilizer P and
organic resources. A ten week incubation study was carried out to determine the
effects of organic and inorganic P sources on phosphorus fractions in three
derived savanna soils. Poultry manure was applied at 0, 0.75g, 1.5g, 2.25g and
3g per 300g weight of soil while single superphosphate was applied at 0.0023g,
0.0046g, 0.0069g and 0.0092g per 300g of soil. Sampling was done at two weeks
interval. At 0 week of the incubation study, Ekiti series had the largest
amount of P fractions i.e. Fe-P, Al-P, residual P, reductant soluble P,
occluded P, organic P and occluded P while Ca-P was high in Apomu series.
However, increases in Fe-P, Al-P, Ca-P and organic P were observed in the three
soil series evaluated and poultry manure was notably effective in reducing P
occlusion. In conclusion, it was observed that irrespective of the soil series
at different stages of the incubation studies, poultry manure and the combined
application of poultry manure and Single superphosphate was highly effective in
increasing P fractions.
Poultry manure, single superphosphate, phosphorus fractions, derived savanna soils