Multielement analysis of soils: a proposal involving a portable X-ray fluorescence equipment

Abstract

Portable instruments are excellent choices to perform precision agriculture since they allow in situ information about soil composition. In such a way, results are obtained quickly and inputs can be applied promptly, depending on the local soil characteristics. This study aims to develop a method to measure inorganic elements at in natura soils using a portable EDXRF (Energy Dispersive X-ray Fluorescence) equipment and multivariate calibration through Partial Least Square Regression (PLS). Seven certified reference standards are used to build the PLS models for Si, K, Ca, Mn and Fe. Two standards are separated for external PLS validation. Finally, the results show that a maximum of 21% is obtained for relative deviation.

Keywords

• Soil
• X-ray fluorescence
• Precision farming