Abstract
Various authors with small variations have used different expressions in order to compute the nutrient uptake for crop roots. These expressions use the nutrient concentration on the root surface and the corresponding influx, which are computed through various numerical models. This study proposes an alternative formula that uses the nutrient concentration computed by a moving boundary model. The formula output was compared with measured uptake of some nutrients in different crops and soils by using experimental data extracted from the literature. The values obtained were compared with predicted uptakes by other numerical estimations as the Barber–Cushman model and our moving boundary model by using the Cushman uptake formula. Better predictions with respect to a single nutrient were obtained for the cases tested. Moreover, an algorithm to computing the nutrient uptake is also given.
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