Dissertations and Theses
Landform and spatial variability of chemical and mineralogical attributes of an Podzol cultivated with sugarcane
Author: Diogo Mazza Barbieri
Keywords: precision agriculture; phosphorus adsorption; gibsita
Summary
Precision agriculture implies the analysis of the spatial variability of the factors of production and the application of the inputs in a localized form and in precise doses. The objective of this work was to analyze the influence of the relief in the spatial variability of the chemical and mineralogical attributes for the application of inputs in variable rate. Two plots of one hectare were delimited in a concave and convex area. 121 samples were taken in each area. The available P contents were differentiated in the two studied areas, with the lowest values of P being found in the convex area in which the highest gibsite contents are present. The formation of the minerals of the clay fraction is conditioned by the variations of the relief , and the convex area presented an environment more favorable to the formation of the gibsite than the concave area, demonstrating that the relief can be used to define more homogeneous area boundaries. Gibsite was the determining factor for the higher adsorption capacity of P and the lower availability of phosphorus in the convex area. The use of the geostatistical technique allowed the precise description of the soil properties.