Journal of Soil Science · 1965 · 58 citations · 3 references
AgricultureAgronomySoil SciencesSoil BiogeochemistrySoil FertilitySoil ScienceNutrient ImmobilizationNutrient MineralizationPhosphorus CyclePhosphorus CyclingSoil Nutrient CyclingSoil PhFertilizer Application RatesPh Effects On MineralizationPhosphate ImmobilizationPhosphorus Fixation In SoilsSoil Phosphate CyclingSoil Phosphorus AvailabilitySoil Phosphorus DynamicsSoil Properties
Summary The fate of superphosphate applied at 500 and 1,000 Ib P 2 O 5 per acre in a field experiment with twenty‐four sites was followed by measuring changes in the L‐value over 5 years. The L‐value decreased exponentially at a rate that was expressed as the time in years for half the applied phosphate to become non‐labile (the half‐life). The two fertilizer rates gave similar values in most of the experiments and half‐life values were satisfactorily measured for nineteen soils; the values ranged from 1 to 56 years. Some relationship between half‐life values and a number of soil properties was sought. The only significant correlation was with the hydrogen‐ion concentration, from which it is suggested that the decrease in labile phosphate could be the result of the formation of a crystalline basic calcium phosphate at a rate that increases with soil pH.
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