Spatial variability of the nutrient distribution in Jerez vineyard soils (Spain)

From a fertility standpoint, the vine has to extract from the soil mineral substances necessary for its existence. However, the amount of certain available nutrients does not always correspond to a proportional increase in quality. Such is the case with nitrogen and organic matter and is in contrast to that of P and K, whose presence has a positive relation to quality. Most of the vintage wines come from vineyards located on calcium-rich soils, which have a complex effect on their quality. It is therefore necessary to characterize the soil for fertilizer practices in an objective way. The production area of Jerez has a notable environmental variability due to the landscape morphology (hills and plains), soil characteristics and the climate conditions due to its oceanic proximity. To assess the fertility of the soils of different vineyards and detect potential imbalances that may impede the growth of the vine and affect its production, a study has been made of distribution parameters such as O.M., P, K, Ca and Fe available in three plots representing the area of Jerez (Cadiz, Spain).The results have shown that OM and Fe presented a greater homogeneity in their concentration for the entire sample area with variances ranging between 0.09 and 0.82, and between 36 and 90, respectively. For the other nutrients analyzed, the variation between different points within the controlled sample plots was very important, noting interval concentrations of 5900 to 12480 ppm for Ca, from 8 to 158 ppm for P and 342 to 1698 ppm for K. The differences observed in the surface horizon remained in the deeper layers.