Direct rapid analysis of trace bioavailable soil macronutrients by chemometrics-assisted energy dispersive X-ray fluorescence and scattering spectrometry
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Date
2012Author
Kaniu, M.I.
Angeyo, K.H.
Mwala, A.K.
Mangala, M.J.
Type
ArticleLanguage
enMetadata
Show full item recordAbstract
Precision agriculture depends on the knowledge and management of soil quality (SQ), which calls for
affordable, simple and rapid but accurate analysis of bioavailable soil nutrients. Conventional SQ analysis
methods are tedious and expensive. We demonstrate the utility of a new chemometrics-assisted energy
dispersive X-ray fluorescence and scattering (EDXRFS) spectroscopy method we have developed for direct
rapid analysis of trace ‘bioavailable’ macronutrients (i.e. C, N, Na, Mg, P) in soils. The method exploits,
in addition to X-ray fluorescence, the scatter peaks detected from soil pellets to develop a model for SQ
analysis. Spectra were acquired from soil samples held in a Teflon holder analyzed using 109Cd isotope
source EDXRF spectrometer for 200 s. Chemometric techniques namely principal component analysis
(PCA), partial least squares (PLS) and artificial neural networks (ANNs) were utilized for pattern recognition
based on fluorescence and Compton scatter peaks regions, and to develop multivariate quantitative
calibration models based on Compton scatter peak respectively. SQ analyses were realized with high CMD
(R2 > 0.9) and low SEP (0.01% for N and Na, 0.05% for C, 0.08% for Mg and 1.98 g g−1 for P). Comparison
of predicted macronutrients with reference standards using a one-way ANOVA test showed no statistical
difference at 95% confidence level. To the best of the authors’ knowledge, this is the first time that an XRF
method has demonstrated utility in trace analysis of macronutrients in soil or related matrices
Citation
Analytica Chimica Acta 729 (2012) 21– 25Publisher
Elsevier Department of physics Department of Land Resource Management and Agricultural Technology,
Subject
ChemometricsEnergy dispersive X-ray fluorescence and scattering
Bio-available soil nutrients
Spectroanalysis