Data/hora: 02/06/2024 05:03:29

Provedor de dados: 	65	
País: 	Brazil	
Título: 	Pedogenic iron oxides in soils of the Acre State, Brazil	
Autores: 	Inda,Alberto Vasconcellos; Fink,Jessé Rodrigo; Santos,Tatiele Fruett dos.	
Data: 	2018-01-01	
Ano: 	2018	
Palavras-chave: 	Mineralogy; X ray diffraction; Hematite; Goethite.	
Resumo: 	ABSTRACT: Iron oxides are environmental indicators and influence on physical and chemical behavior of soils. This research aimed to identify and characterize pedogenic iron oxides in soils of the Acre state, Brazil. The soils developed from sedimentary rocks of the Solimões Formation. Twenty one samples of subsurface horizons were collected from ten soil profiles. Soil samples were analyzed by x-ray diffractometry associated to selective chemical dissolutions. Fe contents in the clay minerals (Fes), in the pedogenic iron oxides (Fed) and in the poorly crystalline oxides (Feo) were determined. The Al3+-substitution and the mean crystal diameter of goethite and hematite were estimated. Soils presented low contents of Fes and Fed. The Fed/Fes ratio indicated soils in the intermediate stage of weathering, with dominance of goethite, hematite and maghemite. This condition of weathering was confirmed by the higher frequency of goethites and hematite with intermediate Al3+-substitution. Goethites have isodimensional forms and hematite have flat plaques forms.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018000800251	
Editor: 	Universidade Federal de Santa Maria	
Relação: 	10.1590/0103-8478cr20180209	
Formato: 	text/html	
Fonte: 	Ciência Rural  v.48 n.8 2018	
Fonte: 	info:eu-repo/semantics/openAccess