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Registro Completo |
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Biblioteca(s): |
Embrapa Agrobiologia. |
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Data corrente: |
07/06/2000 |
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Data da última atualização: |
07/06/2000 |
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Autoria: |
FRANZLUEBBERS, A. J. |
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Título: |
Potential C and N mineralization and microbial biomass from intact and increasingly disturbed soils of varying texture. |
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Ano de publicação: |
1999 |
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Fonte/Imprenta: |
Soil Biology and Biochemistry, Oxford, v. 31, p. 1083-1090, 1999. |
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Idioma: |
Inglês |
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Conteúdo: |
Potential C and N mineralization and soil microbial biomass C were determined following disturbance (i.e. drying and sieving) pretreatments in five soils varying in texture (30-350 mg clay g-1 soil) from the southern Piedmont USA. Soil disturbance by drying (i.e. rewetting following drying at 55 graus centigrafos for 72 h) of intact soil cores resulted in a flush of C mineralization (70% to 2.5-fold greater) during 0-3 d of incubation, but was not significantly different during 3-10 and 10-24 d periods compared with field-moist-intact soil cores. Soil disturbance by sieving resulted in greater C mineralization earlier than later in the incubation and led to significant immobilization of N of surface soil where respiration was highest. Increasing soil disturbance through smaller sieve openings resulted in a 10-60% greater flush of C mineralization that may have been due to disruption of macroaggregates, which protected soil organic C. With a conditioning period of 10 d following rewetting of dried soil, soil microbial biomass C was unaffected by drying or extent of sieving. Soil texture (i.e. clay content) did not interact with disturbance effects. Immobilization of N was predominant in surface soils (0-40 mm) of this bermudagrass pasture, where mineralizable C was very high. Carbon mineralization during 0-3 d was highly related (r2 = 0.96 mais ou menos 0.04) to C mineralization during 0-24 d, basal soil respiration and soil microbial biomass C, although increasing soil disturbance (i.e. drying and extent of sieving) altered these relationships in a predictable manner. I conclude that dried and coarsely sieved soil compares favorably to field-moist-intact soil cores for estimating soil microbial biomass and potential activity in landscapes scoured by various degrees of erosion. MenosPotential C and N mineralization and soil microbial biomass C were determined following disturbance (i.e. drying and sieving) pretreatments in five soils varying in texture (30-350 mg clay g-1 soil) from the southern Piedmont USA. Soil disturbance by drying (i.e. rewetting following drying at 55 graus centigrafos for 72 h) of intact soil cores resulted in a flush of C mineralization (70% to 2.5-fold greater) during 0-3 d of incubation, but was not significantly different during 3-10 and 10-24 d periods compared with field-moist-intact soil cores. Soil disturbance by sieving resulted in greater C mineralization earlier than later in the incubation and led to significant immobilization of N of surface soil where respiration was highest. Increasing soil disturbance through smaller sieve openings resulted in a 10-60% greater flush of C mineralization that may have been due to disruption of macroaggregates, which protected soil organic C. With a conditioning period of 10 d following rewetting of dried soil, soil microbial biomass C was unaffected by drying or extent of sieving. Soil texture (i.e. clay content) did not interact with disturbance effects. Immobilization of N was predominant in surface soils (0-40 mm) of this bermudagrass pasture, where mineralizable C was very high. Carbon mineralization during 0-3 d was highly related (r2 = 0.96 mais ou menos 0.04) to C mineralization during 0-24 d, basal soil respiration and soil microbial biomass C, although increasing soil distu... Mostrar Tudo |
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Palavras-Chave: |
Biomassa microbiana; C; Immobilization; Imobilização; N; Respiration. |
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Thesagro: |
Carbono; Mineralização; Nitrogênio; Respiração; Solo. |
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Thesaurus Nal: |
carbon; microbial biomass; mineralization; nitrogen; soil. |
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Categoria do assunto: |
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Marc: |
LEADER 02652naa a2200313 a 4500
001 1621164
005 2000-06-07
008 1999 bl --- 0-- u #d
100 1 $aFRANZLUEBBERS, A. J.
245 $aPotential C and N mineralization and microbial biomass from intact and increasingly disturbed soils of varying texture.
260 $c1999
520 $aPotential C and N mineralization and soil microbial biomass C were determined following disturbance (i.e. drying and sieving) pretreatments in five soils varying in texture (30-350 mg clay g-1 soil) from the southern Piedmont USA. Soil disturbance by drying (i.e. rewetting following drying at 55 graus centigrafos for 72 h) of intact soil cores resulted in a flush of C mineralization (70% to 2.5-fold greater) during 0-3 d of incubation, but was not significantly different during 3-10 and 10-24 d periods compared with field-moist-intact soil cores. Soil disturbance by sieving resulted in greater C mineralization earlier than later in the incubation and led to significant immobilization of N of surface soil where respiration was highest. Increasing soil disturbance through smaller sieve openings resulted in a 10-60% greater flush of C mineralization that may have been due to disruption of macroaggregates, which protected soil organic C. With a conditioning period of 10 d following rewetting of dried soil, soil microbial biomass C was unaffected by drying or extent of sieving. Soil texture (i.e. clay content) did not interact with disturbance effects. Immobilization of N was predominant in surface soils (0-40 mm) of this bermudagrass pasture, where mineralizable C was very high. Carbon mineralization during 0-3 d was highly related (r2 = 0.96 mais ou menos 0.04) to C mineralization during 0-24 d, basal soil respiration and soil microbial biomass C, although increasing soil disturbance (i.e. drying and extent of sieving) altered these relationships in a predictable manner. I conclude that dried and coarsely sieved soil compares favorably to field-moist-intact soil cores for estimating soil microbial biomass and potential activity in landscapes scoured by various degrees of erosion.
650 $acarbon
650 $amicrobial biomass
650 $amineralization
650 $anitrogen
650 $asoil
650 $aCarbono
650 $aMineralização
650 $aNitrogênio
650 $aRespiração
650 $aSolo
653 $aBiomassa microbiana
653 $aC
653 $aImmobilization
653 $aImobilização
653 $aN
653 $aRespiration
773 $tSoil Biology and Biochemistry, Oxford$gv. 31, p. 1083-1090, 1999.
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Registro original: |
Embrapa Agrobiologia (CNPAB) |
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