Reserves of Organic and Total Phosphorus in the Cultivated and Forested Mollisols

The total and organic P ranged from 270 to 905 ppm and 79 to 529 ppm, respectively and both were lower in 15–30 cm layer as compared to 0–15 cm layer. From 28 to 60 per cent of the total P was in the form of organic P, forest soils having greater percentage in organic form as compared to cultivated soils. Organic P was highly correlated with organic matter (r=0.730), total P (r=0.833) and total N(r =0.605) content of the soil. The correlation coefficients with pH, clay and clay+silt were statistically not significant. Prolonged applications of FYM or fertilizer P increased the content of organic P and its proportion in the total P.