| Registro completo |
| Provedor de dados: |
Scientia Agricola
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| País: |
Brazil
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| Título: |
Copper desorption in a soil with variable charge
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| Autores: |
Casagrande,José Carlos
Jordão,Camila Beig
Alleoni,Luís Reynaldo Ferracciú
Camargo,Otávio Antônio de
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| Data: |
2004-04-01
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| Ano: |
2004
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| Palavras-chave: |
Copper
Desorption
Ionic strength
PH
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| Resumo: |
Adsorption processes of heavy metals in soils have been more extensively studied than desorption, in spite of this latter process being related to nutrient bioavailability in the soil solution. Copper desorption from surface (0-0.2 m) and subsurface (1.0 - 1.2 m) samples of an Anionic Acrudox was studied at two pH values (4.5 and 7.5). Soil samples were incubated with Cu rates varying from 0 to 400 mg kg-1, during 4 and 12 weeks, in the presence of CaCl2 as support electrolyte at concentrations of 0.01 and 0.001 mol L-1. Complete soil adsorption of added Cu was observed at pH 7.5 in all incubation periods, indicating that a 24h-shaking period was enough to reach equilibrium and maximum adsorption. Copper adsorption varied with the incubation period and was much lower at pH 4.5 than at pH 7.5, after the 24 hour-incubation period. After 4 and 12 weeks, Cu adsorption values were higher and similar for all soil samples, irrespective of pH or depth of sampling. The effect of the incubation period on soil Cu adsorption surpassed the pH effect for all Cu rates. The hysteresis was expressive, suggesting that Cu enhances high-energy bonds with the soil colloids. Calcium chloride was not efficient in promoting native soil Cu desorption in the studied concentrations.
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| Tipo: |
Info:eu-repo/semantics/article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162004000200012
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| Editor: |
São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
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| Relação: |
10.1590/S0103-90162004000200012
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| Formato: |
text/html
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| Fonte: |
Scientia Agricola v.61 n.2 2004
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| Direitos: |
info:eu-repo/semantics/openAccess
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