Assessment of reflectance spectroscopy (VIS-NIR) and eletrochemical sensors in field for the measurement of chemical and physical soil attributes

Abstract

The increasing use of technology in field has enabled the investigation of the spatial variability of soil with a high density of data collection. The proximal soil sensing through reflectance (VIS-NIR) and the use of electrochemical sensors has been shown to be promising technologies in this area. In this regard, the proposed project aims to assess the potential of using these technologies in Brazilian soils. Three distinct steps will be sequentially developed. Initially, the goal will be to compare the quality of the readings obtained in the laboratory with the reflectance spectrometers Veris® VIS-NIR (Veris Technologies, Salina, Kansas, USA) and FieldSpec Pro (Analytical Spectral Devices, Boulder, Colorado, USA), assessing their potential to predict attributes of soil fertility. In the second stage, experiments will be conducted in field to generate variability of pH, P and K. To capture these variations we will make readings on the move with a mobile soil sensor platform (Veris Mobile Sensor Platform; Veris Technologies, Salina, Kansas, USA) containing ion-selective electrodes for pH and K. Also, we will use spectral reflectance readings obtained in the move with the Veris VIS-NIR equipment, seeking to use the spectra to generate prediction equations for soil attributes. The final step is to evaluate the efficiency of data acquisition in the move and prediction of attributes of a soil multi-sensor platform (SMSP). To do that, we will merge into a single platform one equipment containing electrical conductivity sensors, ion-selective electrodes for measurement of pH and K and a spectrometer Veris Vis-NIR. By the end of this work, we expect to indicate the potentials and limitations of using these tools directly in field. (AU)