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Registro Completo |
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Biblioteca(s): |
Embrapa Agrobiologia; Embrapa Pantanal. |
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Data corrente: |
15/02/1995 |
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Data da última atualização: |
27/06/1995 |
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Autoria: |
ELLIOTT, E. T.; PALM, C. A.; REUSS, D. E.; MONZ, C. A. |
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Título: |
Organic matter contained in soil aggregates from a tropical chronosequence: correction for sand and light fraction. |
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Ano de publicação: |
1991 |
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Fonte/Imprenta: |
Agric. Ecosyst. Environ., v.34, p.443-451, 1991. |
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Idioma: |
Inglês |
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Conteúdo: |
A cultivation sequence of Ultisols (sandy loam) from the Amazon Basin of Peru was physically fractionate using wet sieving followed by heavy liquid separation and total organic C and N analysis. Soils were sampled to an equivalent plow depth (22.5) in a cultivation chronosequence containing the following treatments: an old growth forest (75 plus years) a 13-year fallowed forest, a 3-year continuous cultivation corn-soybean rotation following a 10-year forest fallow and a 16-year intensively managed corn field. The soil was air dried and re-wetted (misted) to field capacity before shaking for 10 min and wet sieving into five size classes: <0.02, 0.02-0.05, 0.05-0.212, 0.212-1.0 and >1.0 mm. The weight of soil, total organic C and N and percent sand was determined on each size class. Subsamples of each size class were gently stirred in sodium metatungstate (specific gravity=1.8), left overnight and the floating material removed by aspiration. The removed material was filtered through pre-ashed glass fiber filters and analyzed for total organic C and N. The sand content of size classes ranged from 45 to 95%. Light fraction C comprised 24, 28, 14, 5 and 2% of the total C of the size classes ranging from the largest to smalles particle sizes. Total C concentrations were highest in the largest and smallest particle size classes. Within any size class, all treatment had similar C concentration except for the <0.02-mm particles where the 75-year forest has lower concentrations. When corrected for sand content (i.e., expressed on a silt plus clay basis) and with light fraction C subtrated, the organic C content was, with few exceptions, not different among size classes or treatments. However, when all treatments whitin a size class were averaged, the 0.020-0.053-mm class had a higer concentration of C. MenosA cultivation sequence of Ultisols (sandy loam) from the Amazon Basin of Peru was physically fractionate using wet sieving followed by heavy liquid separation and total organic C and N analysis. Soils were sampled to an equivalent plow depth (22.5) in a cultivation chronosequence containing the following treatments: an old growth forest (75 plus years) a 13-year fallowed forest, a 3-year continuous cultivation corn-soybean rotation following a 10-year forest fallow and a 16-year intensively managed corn field. The soil was air dried and re-wetted (misted) to field capacity before shaking for 10 min and wet sieving into five size classes: <0.02, 0.02-0.05, 0.05-0.212, 0.212-1.0 and >1.0 mm. The weight of soil, total organic C and N and percent sand was determined on each size class. Subsamples of each size class were gently stirred in sodium metatungstate (specific gravity=1.8), left overnight and the floating material removed by aspiration. The removed material was filtered through pre-ashed glass fiber filters and analyzed for total organic C and N. The sand content of size classes ranged from 45 to 95%. Light fraction C comprised 24, 28, 14, 5 and 2% of the total C of the size classes ranging from the largest to smalles particle sizes. Total C concentrations were highest in the largest and smallest particle size classes. Within any size class, all treatment had similar C concentration except for the <0.02-mm particles where the 75-year forest has lower concentrations. When... Mostrar Tudo |
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Thesagro: |
Carbono; Matéria Orgânica; Nitrogênio; Solo. |
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Thesaurus Nal: |
organic matter; soil. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 02463naa a2200229 a 4500
001 1614724
005 1995-06-27
008 1991 bl --- 0-- u #d
100 1 $aELLIOTT, E. T.
245 $aOrganic matter contained in soil aggregates from a tropical chronosequence$bcorrection for sand and light fraction.
260 $c1991
520 $aA cultivation sequence of Ultisols (sandy loam) from the Amazon Basin of Peru was physically fractionate using wet sieving followed by heavy liquid separation and total organic C and N analysis. Soils were sampled to an equivalent plow depth (22.5) in a cultivation chronosequence containing the following treatments: an old growth forest (75 plus years) a 13-year fallowed forest, a 3-year continuous cultivation corn-soybean rotation following a 10-year forest fallow and a 16-year intensively managed corn field. The soil was air dried and re-wetted (misted) to field capacity before shaking for 10 min and wet sieving into five size classes: <0.02, 0.02-0.05, 0.05-0.212, 0.212-1.0 and >1.0 mm. The weight of soil, total organic C and N and percent sand was determined on each size class. Subsamples of each size class were gently stirred in sodium metatungstate (specific gravity=1.8), left overnight and the floating material removed by aspiration. The removed material was filtered through pre-ashed glass fiber filters and analyzed for total organic C and N. The sand content of size classes ranged from 45 to 95%. Light fraction C comprised 24, 28, 14, 5 and 2% of the total C of the size classes ranging from the largest to smalles particle sizes. Total C concentrations were highest in the largest and smallest particle size classes. Within any size class, all treatment had similar C concentration except for the <0.02-mm particles where the 75-year forest has lower concentrations. When corrected for sand content (i.e., expressed on a silt plus clay basis) and with light fraction C subtrated, the organic C content was, with few exceptions, not different among size classes or treatments. However, when all treatments whitin a size class were averaged, the 0.020-0.053-mm class had a higer concentration of C.
650 $aorganic matter
650 $asoil
650 $aCarbono
650 $aMatéria Orgânica
650 $aNitrogênio
650 $aSolo
700 1 $aPALM, C. A.
700 1 $aREUSS, D. E.
700 1 $aMONZ, C. A.
773 $tAgric. Ecosyst. Environ.$gv.34, p.443-451, 1991.
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Registro original: |
Embrapa Agrobiologia (CNPAB) |
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