Data/hora: 02/06/2024 02:41:25

Provedor de dados: 	63	
País: 	Brazil	
Título: 	Iron oxides dynamics in a subtropical Brazilian Paleudult under long-term no-tillage management	
Autores: 	Inda,Alberto Vasconcellos; Torrent,José; Barrón,Vidal; Bayer,Cimélio; Fink,Jessé Rodrigo.	
Data: 	2013-02-01	
Ano: 	2013	
Palavras-chave: 	Dissolution; Ferrihydrite; Hematite; Maghemite; Soil management.	
Resumo: 	Replacing conventional tillage (CT) with no-tillage (NT) management alters the pedoenvironment and the rate of topsoil processes, with possible effects on dissolution processes associated with iron oxides and therefore soil mineralogy. This study aimed to determine the effect of NT on the content and distribution of types of iron oxides in a Rhodic Paleudult in southern Brazil. Soil samples were collected at eight depths within the 0.00-0.80 m layer under CT and NT in a long-term experiment (21 years). Mineralogical identification was conducted by X-ray diffraction (XRD), and the Fe content related to specific types of iron oxides determined by selective dissolution and diffuse-reflectance spectroscopy. Kaolinite, quartz, goethite, hematite, and maghemite were identified in the clay fraction. In the NT-managed soil, there was a decrease in the content of crystalline iron oxides and an increase in the content of poorly crystalline iron oxides with increasing proximity to the soil surface. These results suggest that iron oxides are rearranged in this soil by reductive dissolution of the crystalline types and neoformation of metastable ferrihydrite in topsoil layers, which should be assessed further in laboratory studies.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162013000100008	
Editor: 	São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"	
Relação: 	10.1590/S0103-90162013000100008	
Formato: 	text/html	
Fonte: 	Scientia Agricola  v.70 n.1 2013	
Fonte: 	info:eu-repo/semantics/openAccess