Consulta: subjectFacets:"Humification"
Registros recuperados: 4
Data/hora: 06/06/2024 01:19:58

Caracterização espectroscópica (RPE e DRIFT) das frações húmicas durante a compostagem de lodo de fábrica de papel e serragem
Provedor de dados: 190
Autores: Maia, Claudia Maria Branco de Freitas; Fukamachi, Cristiane Regina Budziak; Piccolo, Alessandro; Mangrich, Antonio Sálvio.
The spectroscopic characteristics (DRIFT, UV-visible and EPR) of As características espectroscópicas (DRIFT, UV-visível e RPE) das frações húmicas foram estudadas durante a compostagem de serragem e lodo de fábrica de papel. A espectroscopia de infravermelho (DRIFT) revelou um composto rico em hidroxilas, carboxilatos, alquilas e carboidratos. A fração alifática está concentrada nos ácidos húmicos e na humina. A diminuição da razão E4/E6 durante a compostagem indica um aumento de cadeias orgânicas com ligações duplas conjugadas. Esta redução corresponderia a uma diminuição do teor de lignina e/ou a formação de porfirinas. O RPE mostrou que a humina apresenta a concentração mais alta de radicais livres e a menor concentração de Fe3+ livre.doi:...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Substâncias húmicas; UV-vis; Humificação Humic substances; UV-Vis; Humification.
Ano: 2012
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/303

Pinus afforestation in South Brazilian highlands: soil chemical attributes and organic matter composition
Provedor de dados: 63
Autores: Dick,Deborah Pinheiro; Leite,Simone Benvenuti; Dalmolin,Ricardo Simão Diniz; Almeida,Henrique Cesar; Knicker,Heike.
In the last three decades, exotic tree species are being introduced in the natural pastures of the highlands located at the northeastern part of Rio Grande do Sul State (RS), Brazil. This alteration of land use may impart drastic changes in the soil attributes. In this context, this work aimed to evaluate the impact of Pinus taeda afforestation on soil chemical attributes and organic matter (SOM) composition in Leptosols from Campos de Cima da Serra, RS. Soil samples under eight year old (Pi8) and 30 year old (Pi30) Pinus plantations and under native pasture (NP) were studied. Contents of exchangeable cations and of micronutrients and soil pH were determined. The SOM composition was investigated by means of elemental analyses and FTIR spectroscopy. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: FTIR spectroscopy; Humification; Exchangeable cation; Pastures; Recalcitrance.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162011000200007

Adsorption, immobilization and activity of cellulase in soil: the impacts of maize straw and its humification
Provedor de dados: 52
Autores: Sinegani,Ali Akbar Safari; Sinegani,Mahboobe Safari.
The present work aimed to study some aspects of sorption and immobilization of cellulase molecules on soil components by the analysis of the reactions of cellulase in a soil treated with different levels of maize residue and incubated for 90 days. The analysis of variance showed that the effects of the treatments of maize straw, incubation time and their interaction on cellulase adsorption, desorption and immobilization were statistically significant. The adsorption and immobilization capacities of soil by application of maize straw increased significantly. However they decreased with decreasing the soil organic matter (SOM) after 45 days of incubation. The desorption of adsorbed cellulase molecules from the soil by washing with distilled water depended on...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Maize straw; Humification; Cellulase; Sorption; Immobilization; Activity.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132013000600001

Humic fractions of forest, pasture and maize crop soils resulting from microbial activity
Provedor de dados: 58
Autores: Tavares,Rose Luiza Moraes; Nahas,Ely.
Humic substances result from the degradation of biopolymers of organic residues in the soil due to microbial activity. The objective of this study was to evaluate the influence of three different ecosystems: forest, pasture and maize crop on the formation of soil humic substances relating to their biological and chemical attributes. Microbial biomass carbon (MBC), microbial respiratory activity, nitrification potential, total organic carbon, soluble carbon, humic and fulvic acid fractions and the rate and degree of humification were determined. Organic carbon and soluble carbon contents decreased in the order: forest &gt; pasture &gt; maize; humic and fulvic acids decreased in the order forest &gt; pasture=maize. The MBC and respiratory activity were not...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Humification; Microbial biomass carbon; Potential nitrification; Respiratory activity.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822014000300028