Consulta: creatorFacets:"Silveira,Maria Lucia Azevedo"
Registros recuperados: 4
Data/hora: 02/06/2024 04:43:47

Biosolids and heavy metals in soils
Provedor de dados: Scientia Agricola
Autores: Silveira,Maria Lucia Azevedo; Alleoni,Luís Reynaldo Ferracciú; Guilherme,Luiz Roberto Guimarães.
The application of sewage sludge or biosolids on soils has been widespread in agricultural areas. However, depending on their characteristics, they may cause increase in heavy metal concentration of treated soils. In general, domestic biosolids have lower heavy metal contents than industrial ones. Origin and treatment method of biosolids may markedly influence their characteristics. The legislation that controls the levels of heavy metal contents in biosolids and the maximum concentrations in soils is still controversial. In the long-term, heavy metal behavior after the and of biosolid application is still unknown. In soils, heavy metals may be adsorbed via specific or non-specific adsorption reactions. Iron oxides and organic matter are the most important...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sewage sludge; Adsorption; Speciation; PH; Organic matter.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162003000400029

Energia livre da reação de adsorção de cobre em latossolos ácricos
Provedor de dados: Scientia Agricola
Autores: Silveira,Maria Lucia Azevedo; Alleoni,Luís Reynaldo Ferracciú; Casagrande,José Carlos; Camargo,Otávio Antônio.
Estudou-se a energia livre da reação de adsorção de cobre em amostras superficiais (0-0,2 m) e subsuperficiais (na maior expressão do horizonte B) de três solos paulistas : Latossolo Roxo ácrico (LR), Latossolo variação Una ácrico (LU) e Terra Roxa Estruturada (TE), após a adição de 5, 20, 50, 100, 200, 300, 400 e 600 mg L-1 de cobre. A adsorção de cobre pelos solos foi considerada espontânea, pois a energia livre apresentou valores negativos em todas as concentrações estudadas. Os valores de energia livre diminuíram com o aumento da dose de cobre adicionada. A TE apresentou maior energia livre de adsorção em relação aos Latossolos, sobretudo em superfície. Considerando-se o mesmo solo, os horizontes superficiais apresentaram maior energia livre para as...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Latossolo ácrico; Cobre; Adsorção; Energia livre.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161999000500013

Dissolved organic carbon and bioavailability of N and P as indicators of soil quality
Provedor de dados: Scientia Agricola
Autores: Silveira,Maria Lucia Azevedo.
Soil quality has become an important issue in soil science. Considerable attempts have been made to define soil quality, but a general concept has not yet been accepted by the scientific community. The selection of quantitative indices for soil quality is extremely difficult, and a considerable number of chemical, physical, and biochemical properties have been suggested as potential indicators of soil quality. Because soil organic matter (SOM) can be associated with different soil chemical, physical and biological processes, it has been widely considered as one of the best soil quality indicator. Land use can significantly influence dynamics of organic carbon and N, P, and S cycle. However, changes in total soil organic carbon (SOC) contents in response to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ecosystem management; Sustainability; Indicators of soil quality.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162005000500017

Copper adsorption in tropical oxisols
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Silveira,Maria Lucia Azevedo; Alleoni,Luís Reynaldo Ferracciú.
Cu adsorption, at concentrations between 0 to 800 mg L-1, was evaluated in surface and subsurface samples of three Brazilian soils: a heavy clayey-textured Rhodic Hapludalf (RH), a heavy clayey-textured Anionic ''Rhodic'' Acrudox (RA) and a medium-textured Anionic ''Xanthic'' Acrudox (XA). After adsorption, two consecutive extractions were performed to the samples which received 100 mg L-1 copper. Surface samples adsorbed higher amounts of Cu than the subsurface, and exhibited lower Cu removed after the extractions, reinforcing the influence of the organic matter in the reactions. Cu adsorption was significant in the subsurface horizons of the Oxisols, despite the positive balance of charge, demonstrating the existence of mechanisms for specific...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Isotherms; Desorption; Tropical soil.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132003000400006