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| 14. |  | RENZ, T. E.; NEUFELDT, H.; AYARZA, M. A.; RESCK, D. V. S.; ZECH, W. Microbial biomass, microbial activity, and carbon pools under different land-use systems in the Brazilian cerrados. In: THOMAS, R.; AYARZA, M.A., ed. Sustainable land management for the oxisols of the Latin American savannas: dynamics of soil organic matter and indicators of soil quality. Cali: CIAT, 1999. p.187-197.| Biblioteca(s): Embrapa Cerrados. |
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| 16. | | FUHRMANN, S.; NEUFELDT, H.; WESTERHOF, R.; AYARZA, M. A.; SILVA, J. E. da; ZECH, W. Soil organic carbon, carbohydrates, amino sugars, and potentially mineralizable nitrogen under different land-use systems in oxisols of the Brazilian cerrados. In: THOMAS, R.; AYARZA, M.A., ed. Sustainable land management for the oxisols of the Latin American savannas: dynamics of soil organic matter and indicators of soil quality. Cali: CIAT, 1999. p.110-122.| Biblioteca(s): Embrapa Cerrados. |
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| 19. | | AYARZA, M. A.; THOMAS, R.; ZECH, W.; NEUFELDT, H.; WESTRHOF, R. LILIENFEIN, J.; FREIBAUER, A.; SILVA, J. E. da. Soil indicators of sustainable agropastoral systems. In: CONGRESSO BRASILEIRO DE CIENCIA DO SOLO, 27., 1999, Brasilia, DF. [Ciencia do solo e qualidade de vida: anais]. [Planaltina: Embrapa Cerrados, 1999]. Sessao de posteres 1. Resumo.| Biblioteca(s): Embrapa Cerrados. |
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| 20. | | LILIENFEIN, J.; FREIBAUER, A.; NEUFELDT, H.; WESTERHOF, R.; AYARZA, M. A.; SILVA, J. E. da; RESCK, D. V. S.; ZECH, W. Influence of land-use on the distribution of water stable aggregates and P status of sandy and clayey cerrado oxisols, Brazil. In: SIMPOSIO SOBRE O CERRADO, 8.; INTERNATIONAL SYMPOSIUM ON TROPICAL SAVANNAS, 1., 1996, Brasilia, DF. Biodiversidade e producao sustentavel de alimentos e fibras nos Cerrados: anais... Planaltina: EMBRAPA-CPAC, 1996. p.323-328.| Biblioteca(s): Embrapa Cerrados. |
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 | Acesso ao texto completo restrito à biblioteca da Embrapa Cerrados. Para informações adicionais entre em contato com cpac.biblioteca@embrapa.br. |
Registro Completo
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Biblioteca(s): |
Embrapa Cerrados. |
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Data corrente: |
16/07/1999 |
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Data da última atualização: |
16/07/1999 |
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Autoria: |
RENZ, T. E.; NEUFELDT, H.; AYARZA, M. A.; SILVA, J. E. da; ZECH, W. |
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Título: |
Acid monophosphatase: an indicator of phosphorus mineralization or of microbial activity? a case study from Brazilian cerrados. |
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Ano de publicação: |
1999 |
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Fonte/Imprenta: |
In: THOMAS, R.; AYARZA, M.A., ed. Sustainable land management for the oxisols of the Latin American savannas: dynamics of soil organic matter and indicators of soil quality. Cali: CIAT, 1999. |
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Páginas: |
p.173-186. |
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Idioma: |
Inglês |
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Conteúdo: |
Plant production in the Brazilian savannas, also known as the Cerrados, is limited mainly by low P availability. In tropical soils, rich in sesquioxides, P supply of plants depends heavily on the transformation of organic P by phosphatase enzymes into HPO and H2PO4. We examined two Oxisols-one clayey and one loamy-under different land uses for their potential acid monophophatase activity (PAMA) and potential microbial activity. We measured dimenthyl sulfoxide reduction, pH, total C and N, and NaOH-extractable organic and inorganic P. For all parameters other than pH, values were about twice as high in the clayey as in the loamy soil. Land use was found to strongly affect phosphatase activity, which was reduced by both cropping and reforestation. In the clayey soil, pastures seemed to have a positive effect of continuous cropping to pastures resulted in a rapid recovery of phosphatase activity, microbial activity, and C and N levels. However, it retained high inorganic P (Pi) levels found in fertilizer crops. A comparasion of phosphatase activity with microbial activity, total C and N, and P fractions showed that phosphatase was strongly related to microbial activity in the soil and therefore depended much more on soil organic matter than on soil P levels. We also found that although PAMA is useful for indicating a soil's P mineralization capacity, it does not indicate actual P mineralization rates. However, when combined with findings for microbial activity and Pi, it indicates the level of microbially available P, a lack of which probably implies strong competition between plants and microorganisms for this element. MenosPlant production in the Brazilian savannas, also known as the Cerrados, is limited mainly by low P availability. In tropical soils, rich in sesquioxides, P supply of plants depends heavily on the transformation of organic P by phosphatase enzymes into HPO and H2PO4. We examined two Oxisols-one clayey and one loamy-under different land uses for their potential acid monophophatase activity (PAMA) and potential microbial activity. We measured dimenthyl sulfoxide reduction, pH, total C and N, and NaOH-extractable organic and inorganic P. For all parameters other than pH, values were about twice as high in the clayey as in the loamy soil. Land use was found to strongly affect phosphatase activity, which was reduced by both cropping and reforestation. In the clayey soil, pastures seemed to have a positive effect of continuous cropping to pastures resulted in a rapid recovery of phosphatase activity, microbial activity, and C and N levels. However, it retained high inorganic P (Pi) levels found in fertilizer crops. A comparasion of phosphatase activity with microbial activity, total C and N, and P fractions showed that phosphatase was strongly related to microbial activity in the soil and therefore depended much more on soil organic matter than on soil P levels. We also found that although PAMA is useful for indicating a soil's P mineralization capacity, it does not indicate actual P mineralization rates. However, when combined with findings for microbial activity and Pi, it indica... Mostrar Tudo |
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Thesagro: |
Cerrado; Fosfatase Ácida; Fósforo; Oxisol; Solo. |
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Thesaurus NAL: |
acid phosphatase; Ferralsols; phosphorus; soil. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 02561naa a2200289 a 4500
001 1545409
005 1999-07-16
008 1999 bl uuuu u00u1 u #d
100 1 $aRENZ, T. E.
245 $aAcid monophosphatase$ban indicator of phosphorus mineralization or of microbial activity? a case study from Brazilian cerrados.
260 $c1999
300 $ap.173-186.
520 $aPlant production in the Brazilian savannas, also known as the Cerrados, is limited mainly by low P availability. In tropical soils, rich in sesquioxides, P supply of plants depends heavily on the transformation of organic P by phosphatase enzymes into HPO and H2PO4. We examined two Oxisols-one clayey and one loamy-under different land uses for their potential acid monophophatase activity (PAMA) and potential microbial activity. We measured dimenthyl sulfoxide reduction, pH, total C and N, and NaOH-extractable organic and inorganic P. For all parameters other than pH, values were about twice as high in the clayey as in the loamy soil. Land use was found to strongly affect phosphatase activity, which was reduced by both cropping and reforestation. In the clayey soil, pastures seemed to have a positive effect of continuous cropping to pastures resulted in a rapid recovery of phosphatase activity, microbial activity, and C and N levels. However, it retained high inorganic P (Pi) levels found in fertilizer crops. A comparasion of phosphatase activity with microbial activity, total C and N, and P fractions showed that phosphatase was strongly related to microbial activity in the soil and therefore depended much more on soil organic matter than on soil P levels. We also found that although PAMA is useful for indicating a soil's P mineralization capacity, it does not indicate actual P mineralization rates. However, when combined with findings for microbial activity and Pi, it indicates the level of microbially available P, a lack of which probably implies strong competition between plants and microorganisms for this element.
650 $aacid phosphatase
650 $aFerralsols
650 $aphosphorus
650 $asoil
650 $aCerrado
650 $aFosfatase Ácida
650 $aFósforo
650 $aOxisol
650 $aSolo
700 1 $aNEUFELDT, H.
700 1 $aAYARZA, M. A.
700 1 $aSILVA, J. E. da
700 1 $aZECH, W.
773 $tIn: THOMAS, R.; AYARZA, M.A., ed. Sustainable land management for the oxisols of the Latin American savannas: dynamics of soil organic matter and indicators of soil quality. Cali: CIAT, 1999.
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