Wet or dry? The challenges of NIR to analyse soil samples

Abstract

The increasing use of hand-held or portable infrared instruments (near infrared and mid infrared (MIR)), the development of new algorithms and the increasing use of chemometrics have changed the way that infrared spectroscopy is used to measure different properties in soils, allowing the measurement of samples in the field (on-the go). However, key important aspects on the use of near infrared spectroscopy to analyse soil samples containing high moisture levels still not well understood. A brief summary of the main issues related with applications of NIR spectroscopy to measure soil samples in the field are discussed in this article.