INFLUÊNCIA DA COBERTURA DO SOLO NA DISTRIBUIÇÃO DE POROS E DENSIDADE DE CONECTIVIDADE EM UM LATOSSOLO AVALIADO ATRAVÉS DA MICROTOMOGRAFIA COMPUTADORIZADA 3D

Resumo

The pores of the soil are represented by cavities with different sizes and shapes, determined by the arrangement of solid particles which constitute a volumetric fraction of the soil filled with air, water and nutrients solution. The soil porosity influences in aeration, water conduction and retention, resistance to penetration and branching of the roots in the soil and, consequently use of available water and nutrients. Several techniques can be used to obtain soil porosity index. In the search for new techniques aimed at complementing and adding new data on Ferralsols, high resolution computer microtomography (microCT) appears as a non-destructive and fast analytical technique. MicroCT has been outstanding in the international scenarios and it is more and more present in soil analyses. Analyzing a soil sample by microCT allows obtaining knowledge, in microscale, on shape, size, distribution, volume, area and pore connectivity and having a 3D visualization of the soil sample and its structure. The objective of this work is to use microCT to compare the porosity distribution and pore connectivity density between a soil without vegetation cover and a soil with grass cover, both Ferralsols. Four undisturbed samples of each soil were collected. The results show that the MicroCT technique is an efficient and non-destructive tool for the analysis and characterization of the pore structure of soils protected from and degraded by erosion, underlining clear differences between them, as expected.

Keywords: Porosity Soil, Microtomography Technique, Structure of Soil.