Repositorio
Institucional

Salazar, Osvaldo

Benvenuto, Angelo

Fajardo, Mario

Fuentes, Juan Pablo

Najera, Francisco

Celedon, Ayleen

Pfeiffer, Marco

Renwick, Leah L. R.

Seguel, Oscar

Tapia, Yasna

Casanova, Manuel

Evaluation of a miniaturized portable NIR spectrometer for the prediction of soil properties in Mediterranean central Chile

ELSEVIER

GEODERMA REGIONAL

en

Near-infrared (NIR) spectrometry to estimate soil properties has been evolving toward more portable and accessible equipment in recent years for the prediction of indicators of soil fertility in agroecosystems. There were two objectives of this study. First, to calibrate and validate a miniaturized portable NIR spectrometer NeoSpectra-Module 2.5 with a limited spectral range (1350-2500 nm) for the prediction of total nitrogen (TN), soil organic carbon (SOC), soil pH, clay content and exchangeable cations (Ca2+, Mg2+, K+ and Na+) in dry conditions. And second, to evaluate the use of an external orthogonalization parameter (EPO) to reduce the effect of soil moisture in samples with field moisture conditions collected from Mediterranean central Chile (33 SL to 36 SL). Soil classified as Mollisols, Alfisols and Inceptisols was sampled (n = 170) from 0 to 30 cm depth and scanned with the NeoSpectra spectrometer. The spectrometer showed good performance (R2 > 0.5 and/or RPIQ>1.4) for predictions of SOC and exchangeable cations. When the spectra data without transformation was used (raw spectra) versus transformed spectra, better performance in the predictions was obtained for TN, SOC, pH, clay content and Ca2+. The cubist model (CM) showed better performance than partial least squares (PLSR) for most assessed soil properties. The EPO procedure allowed us to decrease the error due to soil moisture in the prediction of some soil properties. Although the use of a miniaturized portable NIR spectrometer showed promising results for prediction of soil properties, future testing should increase the number of soil samples, vary the spectral data processing, and/or test new miniaturized portable NIR spectrometers with a wider spectral range.

2023

artículo original

10.1016/j.geodrs.2023.e00675

PDF

External parameter orthogonalization

Hyperspectral image

Partial least squares

Conditional regression trees

Pedometrics

Near-infrared spectroscopy

Mollisols

Alfisols

Inceptisols

Agricultura

Ortogonalización de parámetros externos

Imagen hiperespectral

Mínimos cuadrados parciales

Árboles de regresión condicional

Pedometría

Espectroscopia de infrarrojo cercano

Molisoles

Alfisoles

Inceptisoles

artículo original

versión publicada

metadata

metadata

WOS:001059492800001

2352-0094

Agricultura

ANID-FONDECYT 1201497

ANID-FONDECYT 3210036

ANID-FONDEQUIP EQM160084

ANID FONDECYT 1201497

ANID FONDECYT 3210036

ANID FONDEQUIP EQM160084