Developing Spectroscopic and Imaging Techniques for Advanced Studies in Soil Physics Based on Results Obtained at Embrapa Instrumentation

The development of techniques based on computed tomography, X- or gamma-ray transmission or scattering, magnetic resonance imaging, particle-induced X-ray emission, and neutron activation analysis has enabled advanced research in the characterization of agricultural soil samples, both in laboratories and the crop environment. This paper discusses the pioneering work of Embrapa Instrumentation regarding the customization of these techniques to solve the problems encountered in the field of soil physics. This work has led to new insights into the management processes for food production. The studies include the modeling and evaluation of spatial and temporal variability of agricultural soil bulk density and water content measures, the distribution of macro- and micropores, the evaluation of expansive and collapsible soils, root development, fluid phase change, models based on multifractals, cellular automata and invasion percolation theory, and the elemental analysis of macro- and micronutrients, such as heavy metals. Such studies have improved agricultural management techniques and are useful to rationalize inputs and minimize the environmental impacts resulting from possible anthropization processes in the use of natural resources. In addition, the potential opportunities for the continued use of the spectroscopic and imaging techniques in soil science are described.