Relationship between elemental content determined via portable X-ray fluorescence spectrometry and traditional acid-digestion-based methods in tropical soils

Context. Studies comparing the elemental contents obtained via portable X-ray fluorescence (pXRF) spectrometry under different scanning conditions and traditional time-consuming concentrated acid-digestion-based methods are rare in tropical soils. Aims. (1) To compare the contents of Al, Ca, Cu, Fe, K, Mn, Zn, Cr, Ni, Ti, V and Zr obtained by pXRF with the results of the USEPA 3051a method; and (2) to evaluate the impacts of different conditions on the pXRF results. Methods. Soil samples were analysed with pXRF under five conditions: field (F), post-field (PF), air-dried fine earth (ADFE, Keywords: chemical attributes modelling, environmentally-friendly method, geochemistry, ICP atomic emission spectroscopy, linear regression, pedology, proximal sensors, USEPA 3051a.
Introduction Soil is a fundamental, slowly-renewable natural resource for many human activities, sustaining life on the planet and aiding the economic development of nations (Adhikari and Hartemink 2016). Soil characterisation [...]