Evaluation of water and ammonium acetate tests as indices for available phosphorus in limed soils
Journal of Agricultural Science in Finland 61(1): 1-6
The water and acid acetate extractions as predictors of the P uptake by plants were compared in a two-year pot experiment and a simultaneous incubation test. The accuracy of these methods was dissimilarly affected by individual cultivation measures, such as the addition of nutrient salts and liming. In contrast to acetate-extractable P, the water-soluble P proved to be sensitive to the salt addition reducing the water extraction test values markedly. On the other hand, in limed soils the water-soluble P seemed to be more closely related to the P uptake by plants than the acetate-extractable P which tended to overestimate available reserves.