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Registro Completo |
Biblioteca(s): |
Embrapa Pantanal. |
Data corrente: |
15/02/1995 |
Data da última atualização: |
04/04/2017 |
Autoria: |
ELLIOTT, E. T.; CAMBARDELLA, C. A. |
Título: |
Physical separation on soil organic matter. |
Ano de publicação: |
1991 |
Fonte/Imprenta: |
Agriculture, Ecosystems and Environment, v.34, p.407-419, 1991. |
Idioma: |
Inglês |
Conteúdo: |
The distribution of organic matter within physical fractions of the soil can be assessed by disruption of the soil structure, followed by the separation of physical fractions based on particle size or density. Disruption of the soil structure can be accomplished by physical or chemical methods, or some combination of the two. The most commonly used methods of physical disruption are shaking and sonication. Dhaking is the more gentle method with the advantage of being able to obtain a wide range of disrupting energies relatively easily. Sonication can impart more energy to the soil a shorter period of time. The greatest potential problem associated with the use of sonication is the redistribution of organic matter among size/density fractions. Chemical extraction methods are commonly used prior to disruption of soil for particle size analysis. Some chemical dispersants can selectively solubilize organic matter. This specificity can be used to determine the kinds and amounts of organic matter that bind particles into agregates. Three methods of physical separation of soil have been used, sieving, sedimentation and densiometry. Sieving separates soil particles based strictly on size and is used primarily for aggregate separation of non-disrupted soil samples. Sedimentation separates particles based on an equivalent spherical diameter, which may vary in size, shape and density. It is most often used in conjunction with a disruption pretreatment to obtain fine fractions. Densitometry separates particles based on the weight per unit volume, independent of size and shape, and is used to separate lighter from heavier fractions. It is possible to combine any or all of these separation methods in order to isolate, for instance, organic matter from a particular size fraction that has a specific density. MenosThe distribution of organic matter within physical fractions of the soil can be assessed by disruption of the soil structure, followed by the separation of physical fractions based on particle size or density. Disruption of the soil structure can be accomplished by physical or chemical methods, or some combination of the two. The most commonly used methods of physical disruption are shaking and sonication. Dhaking is the more gentle method with the advantage of being able to obtain a wide range of disrupting energies relatively easily. Sonication can impart more energy to the soil a shorter period of time. The greatest potential problem associated with the use of sonication is the redistribution of organic matter among size/density fractions. Chemical extraction methods are commonly used prior to disruption of soil for particle size analysis. Some chemical dispersants can selectively solubilize organic matter. This specificity can be used to determine the kinds and amounts of organic matter that bind particles into agregates. Three methods of physical separation of soil have been used, sieving, sedimentation and densiometry. Sieving separates soil particles based strictly on size and is used primarily for aggregate separation of non-disrupted soil samples. Sedimentation separates particles based on an equivalent spherical diameter, which may vary in size, shape and density. It is most often used in conjunction with a disruption pretreatment to obtain fine fractions. Densitom... Mostrar Tudo |
Thesagro: |
Matéria Orgânica; Solo. |
Thesaurus Nal: |
organic matter; soil. |
Categoria do assunto: |
-- |
Marc: |
LEADER 02297naa a2200181 a 4500 001 1783889 005 2017-04-04 008 1991 bl --- 0-- u #d 100 1 $aELLIOTT, E. T. 245 $aPhysical separation on soil organic matter. 260 $c1991 520 $aThe distribution of organic matter within physical fractions of the soil can be assessed by disruption of the soil structure, followed by the separation of physical fractions based on particle size or density. Disruption of the soil structure can be accomplished by physical or chemical methods, or some combination of the two. The most commonly used methods of physical disruption are shaking and sonication. Dhaking is the more gentle method with the advantage of being able to obtain a wide range of disrupting energies relatively easily. Sonication can impart more energy to the soil a shorter period of time. The greatest potential problem associated with the use of sonication is the redistribution of organic matter among size/density fractions. Chemical extraction methods are commonly used prior to disruption of soil for particle size analysis. Some chemical dispersants can selectively solubilize organic matter. This specificity can be used to determine the kinds and amounts of organic matter that bind particles into agregates. Three methods of physical separation of soil have been used, sieving, sedimentation and densiometry. Sieving separates soil particles based strictly on size and is used primarily for aggregate separation of non-disrupted soil samples. Sedimentation separates particles based on an equivalent spherical diameter, which may vary in size, shape and density. It is most often used in conjunction with a disruption pretreatment to obtain fine fractions. Densitometry separates particles based on the weight per unit volume, independent of size and shape, and is used to separate lighter from heavier fractions. It is possible to combine any or all of these separation methods in order to isolate, for instance, organic matter from a particular size fraction that has a specific density. 650 $aorganic matter 650 $asoil 650 $aMatéria Orgânica 650 $aSolo 700 1 $aCAMBARDELLA, C. A. 773 $tAgriculture, Ecosystems and Environment$gv.34, p.407-419, 1991.
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Embrapa Pantanal (CPAP) |
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Registro Completo
Biblioteca(s): |
Embrapa Amazônia Oriental. |
Data corrente: |
15/04/2008 |
Data da última atualização: |
23/11/2022 |
Tipo da produção científica: |
Resumo em Anais de Congresso |
Autoria: |
CRILL, P.; KELLER, M.; SILVA, H.; DIAS, J. D.; OLIVEIRA, R. C. de. |
Afiliação: |
Patrick Crill, Stockholm University; Michael Keller, International Institute of Tropical Forestry; Hudson Silva, UFPA; Jadson Dizencourt Dias, Fundação Floresta Tropical; RAIMUNDO COSME DE OLIVEIRA JUNIOR, CPATU. |
Título: |
Trace gas fluxes from through-canopy measurements in an upland forest of the Eastern Brazilian Amazon. |
Ano de publicação: |
2007 |
Fonte/Imprenta: |
In: SCIENCE TEAM MEETING, 11., 2007, Salvador. Book of Abstracts... Manaus: LBA-ECO, 2007. |
Idioma: |
Inglês |
Notas: |
Abstract ID: 24. Publicado também on-line. |
Palavras-Chave: |
Brasil; Gas carbono; Gas traço; Óxido de nitrogênio; Pará. |
Thesagro: |
Floresta; Metano. |
Thesaurus NAL: |
Amazonia. |
Categoria do assunto: |
-- |
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/42329/1/ID39815.pdf
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Marc: |
LEADER 00783nam a2200253 a 4500 001 1403243 005 2022-11-23 008 2007 bl uuuu u00u1 u #d 100 1 $aCRILL, P. 245 $aTrace gas fluxes from through-canopy measurements in an upland forest of the Eastern Brazilian Amazon.$h[electronic resource] 260 $aIn: SCIENCE TEAM MEETING, 11., 2007, Salvador. Book of Abstracts... Manaus: LBA-ECO$c2007 500 $aAbstract ID: 24. Publicado também on-line. 650 $aAmazonia 650 $aFloresta 650 $aMetano 653 $aBrasil 653 $aGas carbono 653 $aGas traço 653 $aÓxido de nitrogênio 653 $aPará 700 1 $aKELLER, M. 700 1 $aSILVA, H. 700 1 $aDIAS, J. D. 700 1 $aOLIVEIRA, R. C. de
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