Title:	Multivariate analysis of images in spectrophotometric methods: quantification of soil organic matter.
Authors:	MORAIS, P. A. de O. SOUZA, D. M. de MADARI, B. E.
Affiliation:	PEDRO AUGUSTO DE OLIVEIRA MORAIS, UFG; DIEGO MENDES DE SOUZA, Polícia Civil, Distrito Federal, DF; BEATA EMOKE MADARI, CNPAF.
Date Issued:	2021
Citation:	European Journal of Chemistry, v. 12, n. 4, p. 377-381, Dec. 2021.
Description:	Soil organic matter (SOM) is usually quantified by Walkley-Black titration method or using a spectrophotometric method. This study proposes an alternative method for quantification of SOM using digital image from scanner and mathematical algorithms to replace titration and spectrophotometry procedures. For this, after SOM oxidation by potassium dichromate, digital images were acquired. Posteriorly, extraction of RGB color histograms from images have occurred, followed by the use of multivariate calibration method: partial least squares (PLS). Six soil samples were analyzed. We used the Walkley-Black method as reference. SOM was estimated by images using the PLS tool. The new method, besides being a fast, low cost, and more operational alternative, presented statistically equal results in relation to the reference method, as assessed by the Student t-test and F-test at 95 % confidence.
Thesagro:	Matéria Orgânica Solo Espectrometria
NAL Thesaurus:	Soil organic matter Scanners Digital images Spectrophotometers
Keywords:	Walkley-Black method Partial least squares
ISSN:	2153-2257
DOI:	10.5155/eurjchem.12.4.377-381.2122
Type of Material:	Artigo de periódico
Access:	openAccess
Appears in Collections:	Artigo em periódico indexado (CNPAF)