Abstract

The chemical potential of phosphorus in soil solution estimates the free energy or the available energy. The phosphato potential values of the soil samples after flooding for 15 days and 35 days correlated well with the uptake in flooded soils. But the phos phate potential of air dried soils did not correlate with the uptake. Since the phosphate potential values were significantly related to the uptake of P, it may serve as a good index of phosphorus availability in waterlogged soils. However, the ratio between the change in quantity factor and change in intensity known as "differential capacity" or "0/1 relations" would serve as a good index of P availability since the "intensity factor" changes with the "Quantity factor" due to the dynamism of waterlogged soils. Hence the evaluation of "buffering capacity" or the "O/1 relation" in suggested for realistic soil test.

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