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Registro Completo |
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Biblioteca(s): |
Embrapa Meio Norte / UEP-Parnaíba. |
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Data corrente: |
29/10/1996 |
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Data da última atualização: |
29/10/1996 |
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Autoria: |
PARFITT, R. L.; GILTRAP, D. J.; WHITTON, J. S. |
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Afiliação: |
Manaaki Whenua, New Zealand. |
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Título: |
Contribution of organic matter and clay minerals to the cation exchange capacity of soils. |
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Ano de publicação: |
1995 |
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Fonte/Imprenta: |
Communications of Soil Science Plant Analysis, v.26, n.9-10, p.1343-1355, 1995. |
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Idioma: |
Inglês |
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Conteúdo: |
The cation exchange capacity (CEC) at pH 7 was measured for samples of347 A horizons of New Zealand soils. The mean CEC was 22.1 cmolc/kg for the A horizons and 15.2 cmolc/kg for the B horizons. Multiple regressions were carried out for CEC against organic carbon (C), clay content, and the content of seven groups of clay minerals. The results, significant at p<0.001, were consistent with most of the CEC arising from soil organic matter. For the samples of A horizon, the calculated CEC was 221 cmolc/kg per unit C and for the B horizons was 330cmolc/kg C. There was also contribution from sites on clay minerals. Multiple regression indicated that smectite had a higher CEC (70 cmolc/kg) than other minerals but it was not as high as that of type smectites; kaolin minerals had the lowest CEC. There was a significant effect of interaction between organic matter and some clay minerals on the CEC. Samplesfrom B horizons containing allophane had lower CEC than those not containing allophane which is consistent with allophane reacting with carboxyl groups on organic matter. For the samples from the A horizons, however the CEC was higher when allophane was present. |
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Palavras-Chave: |
Capacidade de troca de cations; Minerais de argila; Soils; Solos. |
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Thesagro: |
Matéria Orgânica. |
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Thesaurus Nal: |
cation exchange capacity; clay minerals; organic matter. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 01892naa a2200241 a 4500
001 1078256
005 1996-10-29
008 1995 bl --- 0-- u #d
100 1 $aPARFITT, R. L.
245 $aContribution of organic matter and clay minerals to the cation exchange capacity of soils.
260 $c1995
520 $aThe cation exchange capacity (CEC) at pH 7 was measured for samples of347 A horizons of New Zealand soils. The mean CEC was 22.1 cmolc/kg for the A horizons and 15.2 cmolc/kg for the B horizons. Multiple regressions were carried out for CEC against organic carbon (C), clay content, and the content of seven groups of clay minerals. The results, significant at p<0.001, were consistent with most of the CEC arising from soil organic matter. For the samples of A horizon, the calculated CEC was 221 cmolc/kg per unit C and for the B horizons was 330cmolc/kg C. There was also contribution from sites on clay minerals. Multiple regression indicated that smectite had a higher CEC (70 cmolc/kg) than other minerals but it was not as high as that of type smectites; kaolin minerals had the lowest CEC. There was a significant effect of interaction between organic matter and some clay minerals on the CEC. Samplesfrom B horizons containing allophane had lower CEC than those not containing allophane which is consistent with allophane reacting with carboxyl groups on organic matter. For the samples from the A horizons, however the CEC was higher when allophane was present.
650 $acation exchange capacity
650 $aclay minerals
650 $aorganic matter
650 $aMatéria Orgânica
653 $aCapacidade de troca de cations
653 $aMinerais de argila
653 $aSoils
653 $aSolos
700 1 $aGILTRAP, D. J.
700 1 $aWHITTON, J. S.
773 $tCommunications of Soil Science Plant Analysis$gv.26, n.9-10, p.1343-1355, 1995.
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Registro original: |
Embrapa Meio Norte / UEP-Parnaíba (CPAMN-UEPP) |
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