Multivariate Analysis and Machine Learning in Properties of Ultisols (Argissolos) of Brazilian Amazon

AUTOR(ES)

Souza, Cristiano Marcelo Pereira de, Thomazini, André, Schaefer, Carlos Ernesto Gonçalves Reynaud, Veloso, Gustavo Vieira, Moreira, Guilherme Musse, Fernandes Filho, Elpídio Inácio

FONTE

Rev. Bras. Ciênc. Solo

DATA DE PUBLICAÇÃO

06/12/2018

RESUMO

ABSTRACT: Ultisols are the most common soil order in the Brazilian Amazon. The Legal Amazon (LA) has an area of 5 × 106 km2, with few accessible areas, which restricts studies of soils at a detailed level. The pedological properties can be estimated more efficiently using statistical procedures and machine learning techniques, tools which are capable of recognizing patterns in a large soil database. We analyzed the main chemical and physical properties of the B horizons of the Ultisols of the Brazilian Amazon, as well as the spatial variability of the most explanatory properties of these horizons. Physical and chemical data of 1,068 profiles of the RadamBrasil Project were used. A principal component analysis (PCA) was applied and the most explanatory variables were separated by morphostructural units and climate zones. The technique of machine learning was used for spatialization of the explanatory variables based on predictive covariates. In general, the horizons are thick, clay, with a predominance of negative charges, and low levels of exchangeable cations. The variables retained in the PCA were: sum of bases (SB), Al3+, degree of flocculation (Floc), ∆pH, and organic carbon content (C). Areas of greater precipitation have low SB, with higher values in the basement complex (BC) and in areas under the Andean influence. Higher levels of Al3+ and degrees of flocculation were also associated with greater precipitation. However, the soils are predominantly electronegative, showing a kaolinitic mineralogy. The C contents in general were low, with an increase in more humid zones due to the process of mineralization and illuviation (podzolization), and in the BC due to the protection of C by the aggregation of clay. The use of multivariate analysis allowed a better understanding of the Ultisols’ main properties in different morphostructural and climatic domains, and its spatialization facilitated the interpretation of properties and their relationships with environmental characteristics in the Legal Amazon.

Documentos Relacionados

• CLASSIFICATION OF Phaseolus lunatus L. USING IMAGE ANALYSIS AND MACHINE LEARNING MODELS
• INTELIGÊNCIA COMPUTACIONAL APLICADA EM MACHINE LEARNING
• Estimating credit and profit scoring of a Brazilian credit union with logistic regression and machine-learning techniques
• Environmental and socioeconomic analysis of malaria transmission in the Brazilian Amazon, 2010–2015
• Artificial intelligence and machine learning in pediatrics and neonatology healthcare