Geotechnologies in detailed pedological digital mapping and Brazilian spectral soil library: development and applications

Abstract

The current project aims to act in many soil knowledge fields through geotechnologies using laboratorial, terrestrial punctual and continuous platforms, aerial and orbital levels. This will be organized into 6 projects as follows: 1. Brazilian Spectral library; 2. Satellite images on soil mapping; 3. Geotechnologies for in-situ soil mapping; 4. Stratigraphy on soil mapping; 5. Geotechnology for digital soil mapping. The first theme aims the implementation of a Brazil's soil spectral library. Soil reflectance spectra will be obtained and organized from the broadest attainable regions. The object is the development of a database with soil patterns via spectra accessible to the community, leading to implement its use in future soil surveys. The second theme regards the development of a detailed soil map of an important region, Piracicaba - SP, through geotechnologies. In order to accomplish this goal, many subprojects will be fulfilled. The first will be the compartmentalization of stratigraphic surfaces according to their geological and geomorphological aspects. A mosaic with satellite images with correction for reflectance in 3D software will be made as well, in order to observe the surface with bare soil. Also an aerial image will be taken by a hyperspectral sensor with 620 bands to relate with detailed spectral characteristics of soils. Photopedology work in 3D software will be accomplished. Within the compartments, several transect points will be allocated along the area to be evaluated by boreholes and trenches at the field (patterns). After the conclusion of evaluation and sampling, soil samples will be analyzed in laboratory and by sensor acquiring a spectral database (DB). With the DB, in addition with all the information layers, three pilot areas within each compartment will be chosen, where a detailed fieldwork will be made through geotechnologies. In this stage, in-situ mapping work with geotechnological equipment (field spectroradiometer, colorimeters, GPS, gamaespectrometry, computers and geographic information systems) will be made in punctual. Such tools will support the pedologist decision in soil interpretation at real time. Added all the knowledge acquired, the methodology will be applied in soil mapping based on a mix of traditional and geotechnological. There are two products expected as a result of this project: a library available to public and a detailed soil map supported by a new geotechnological methodology. (AU)