Dissertations and Theses
Spatial variability and atributtes of Latossol with differents landforms
Author: Zigomar Menezes de Souza
Keywords: geostatistics, soil genesis, soil-landscape relation, Saccharum officinarum.
Summary
In Brazil, few studies assess the spatial variability of physical, chemical and mineralogical attributes within a soil mapping unit. The objective of this work was to study the spatial variability of physical, chemical and mineralogical attributes, to characterize the micromorphology and to optimize the number of samples in an Eutrophic Red Latosol under different relief forms in the Jaboticabal-SP region. The soils were sampled at the crossing points of a mesh, with regular intervals of 10 m, making a total of 100 points. All the studied variables presented spatial distribution and the spatial variability was greater in the form of concave and convex relief. The application of the Sanos program allowed to verify that all the physical and chemical attributes need a greater number of sampling points in the soils of the concave and convex form with respect to the soils of the linear form. The compartment I (linear form) showed a higher Ct / (Ct + Gb) ratio and relative crystallization degree of kaolinite, resulting in higher values of soil resistance to soil penetration and density and lower values for saturated soil hydraulic conductivity and stability of aggregate. The high values for soil density, microporosity and soil resistance to penetration and low for macroporosity, total porosity and hydraulic conductivity of the soil saturated mainly in the depth of 0.2-0.4 m, indicated compaction in this layer, being confirmed by the image analysis (micromorphology). The identification and mapping of the shape of the relief in the study area proved to be very efficient in understanding the causes of the spatial variability of the attributes studied. Therefore, variations in the forms of relief condition differentiated variability for the physical, chemical and mineralogical attributes of the soil.