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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: |
NEUFELDT, H.; SILVA, J. E. da; AYARZA, M. A.; ZECH, W. |
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Título: |
Phosphorus fractions under different land-use systems in oxisols of the 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.146-158. |
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Idioma: |
Inglês |
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Conteúdo: |
We examined whole-soil samples and particle-size fractions to study the distribution of different phosphorus (P) fractions after land-use change from native savanna to crops, pastures, and reforestation on clayey and loamy Oxisols of the Brazilian savannas. Phosphorus was extracted sequentially, according to a modified hedley procedure, into inorganic and organic P (NaOH-extractable Pi and Po, respectively), and recalcitrant P (Phc1 and Pres). Under natural conditions of strong P deficiency, over 60% of NaOH-extractable P was organic, reflecting the high contribuint of Po to plant nutrition. Fertilization elevated inorganic Po. The increase of inorganic P forms from fertilizer P was greatest in the Pi and lowest in the Pres fractions. After fertilization, the reforested sites maintained high NaOH-extractable P through efficient recycling, whereas at the crop and pasture sites, P tended to accumulate in recalcitrant forms. Possibly, the adsorption of P to oxyhydroxides was reduced at the more acid reforested sites by complexation of Fe and Al oxides with organic acids. The ratio of NaOH-extractable Pi to Po appeared to effectively reflect the P status of the land-use systems and P deficiency increased in ascending order from native savanna > pasture > reforestation > crop, independently of soil type. The particle-size separates reflected P transformations along a biological and mineralogical gradient, which is discussed with respect to origin and distribution of natural and fertilizer P forms. That is, (1) P in particle-size separates was enriched in the clay and depleted in the sand fractions such that 70%-87% of total P was bound in the clay; (2) residual P increased relatively at the expense of HCl-extractable P with decreasing particle-size, indicating a continuously stronger adsorption to oxyhydroxides; (3) the proportions of organic P were generally lowest in the 20-50-um fraction because P in particulate organic matter was already depleted and transformed into microbially mediated Po, which was enriched in the clay and silt fractions; (4) fertilizer P accumulated in the 20-50-um fraction and was subsequently transferred to the silt and clay fractions but remained largely in inorganic form. MenosWe examined whole-soil samples and particle-size fractions to study the distribution of different phosphorus (P) fractions after land-use change from native savanna to crops, pastures, and reforestation on clayey and loamy Oxisols of the Brazilian savannas. Phosphorus was extracted sequentially, according to a modified hedley procedure, into inorganic and organic P (NaOH-extractable Pi and Po, respectively), and recalcitrant P (Phc1 and Pres). Under natural conditions of strong P deficiency, over 60% of NaOH-extractable P was organic, reflecting the high contribuint of Po to plant nutrition. Fertilization elevated inorganic Po. The increase of inorganic P forms from fertilizer P was greatest in the Pi and lowest in the Pres fractions. After fertilization, the reforested sites maintained high NaOH-extractable P through efficient recycling, whereas at the crop and pasture sites, P tended to accumulate in recalcitrant forms. Possibly, the adsorption of P to oxyhydroxides was reduced at the more acid reforested sites by complexation of Fe and Al oxides with organic acids. The ratio of NaOH-extractable Pi to Po appeared to effectively reflect the P status of the land-use systems and P deficiency increased in ascending order from native savanna > pasture > reforestation > crop, independently of soil type. The particle-size separates reflected P transformations along a biological and mineralogical gradient, which is discussed with respect to origin and distribution of natural and f... Mostrar Tudo |
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Thesagro: |
Cerrado; Composto Orgânico; Fósforo; Fracionamento; Uso da Terra. |
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Thesaurus Nal: |
fractionation; land use; organic compounds; phosphorus. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 03118naa a2200277 a 4500
001 1545407
005 1999-07-16
008 1999 bl uuuu u00u1 u #d
100 1 $aNEUFELDT, H.
245 $aPhosphorus fractions under different land-use systems in oxisols of the Brazilian cerrados.
260 $c1999
300 $ap.146-158.
520 $aWe examined whole-soil samples and particle-size fractions to study the distribution of different phosphorus (P) fractions after land-use change from native savanna to crops, pastures, and reforestation on clayey and loamy Oxisols of the Brazilian savannas. Phosphorus was extracted sequentially, according to a modified hedley procedure, into inorganic and organic P (NaOH-extractable Pi and Po, respectively), and recalcitrant P (Phc1 and Pres). Under natural conditions of strong P deficiency, over 60% of NaOH-extractable P was organic, reflecting the high contribuint of Po to plant nutrition. Fertilization elevated inorganic Po. The increase of inorganic P forms from fertilizer P was greatest in the Pi and lowest in the Pres fractions. After fertilization, the reforested sites maintained high NaOH-extractable P through efficient recycling, whereas at the crop and pasture sites, P tended to accumulate in recalcitrant forms. Possibly, the adsorption of P to oxyhydroxides was reduced at the more acid reforested sites by complexation of Fe and Al oxides with organic acids. The ratio of NaOH-extractable Pi to Po appeared to effectively reflect the P status of the land-use systems and P deficiency increased in ascending order from native savanna > pasture > reforestation > crop, independently of soil type. The particle-size separates reflected P transformations along a biological and mineralogical gradient, which is discussed with respect to origin and distribution of natural and fertilizer P forms. That is, (1) P in particle-size separates was enriched in the clay and depleted in the sand fractions such that 70%-87% of total P was bound in the clay; (2) residual P increased relatively at the expense of HCl-extractable P with decreasing particle-size, indicating a continuously stronger adsorption to oxyhydroxides; (3) the proportions of organic P were generally lowest in the 20-50-um fraction because P in particulate organic matter was already depleted and transformed into microbially mediated Po, which was enriched in the clay and silt fractions; (4) fertilizer P accumulated in the 20-50-um fraction and was subsequently transferred to the silt and clay fractions but remained largely in inorganic form.
650 $afractionation
650 $aland use
650 $aorganic compounds
650 $aphosphorus
650 $aCerrado
650 $aComposto Orgânico
650 $aFósforo
650 $aFracionamento
650 $aUso da Terra
700 1 $aSILVA, J. E. da
700 1 $aAYARZA, M. A.
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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| Registros recuperados : 86 | |
| 41. |  | DINKELMEYER, H.; LEHMANN, J.; KAISER, K.; TEIXEIRA, W. G.; RENCK, A.; ZECH, W. Fate of applied N fertilizer in mixed cropping systems in the central Amazon. In: CONGRESSO BRASILEIRO DE SISTEMAS AGROFLORESTAIS, 3., 2000, Manaus. Sistemas agroflorestais: manejando a biodiversidade e compondo a paisagem rural - resumos expandidos. Manaus: Embrapa Amazonia Ocidental, 2000. p. 196-197.| Tipo: Artigo em Anais de Congresso |
| Biblioteca(s): Embrapa Amazônia Ocidental. |
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| 47. | | LILIENFEIN, J.; WILCKE, W.; VILELA, L.; LIMA, S. do C.; THOMAS, R.; ZECH, W. Effect of no-tillage and conventional tillage systems on the chemical composition of soil solid phase and soil solution of brazilian savanna oxisols. Journal of Plant Nutrition and Soil Science, Berlin, v. 163, p. 411-419, 2000.| Biblioteca(s): Embrapa Cerrados. |
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| 52. | | LEHMANN, J.; SILVA JUNIOR, J. P. da; STEINER, C.; NEHLS, T.; ZECH, W.; GLASER, B. Nutrient availability and leaching in an archaeological Anthrosol and a Ferralsol of the Central Amazon basin: fertilizer, manure and charcoal amendments. Plant and Soil, v. 249, p. 343-357, 2003.| Tipo: Artigo em Periódico Indexado | Circulação/Nível: Internacional - A |
| Biblioteca(s): Embrapa Amazônia Ocidental. |
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| 54. | | LEHMANN, J.; SCHROTH, G.; TEIXEIRA, W.; WOLFGANG ZECH, W.; CRAVO, M. da S. Nutrient and water dynamics in a multi-strata agroforestry system. In: CONGRESSO BRASILEIRO EM SISTEMAS AGROFLORESTAIS, 2., 1998, Belém, PA. Sistemas agroflorestais no contexto da qualidade ambiental e competitividade: resumos expandidos. Belém, PA: Embrapa-CPATU, 1998. p. 38-41.| Tipo: Artigo em Anais de Congresso |
| Biblioteca(s): Embrapa Amazônia Ocidental. |
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| 57. | | AMELUNG, W.; MAARTIUS, C.; GARCIA, M.; KUEPER, U.; ULBRICH, D.; ZECH, W. Organic matter in termite mounds of an Amazonian rain forest. In: SHIFT-WORKSHOP, 3., 1998, Manaus. Program, abstracts of presentations and posters... Hamburg: GKSS, 1998. p. C50.| Tipo: Resumo em Anais de Congresso |
| Biblioteca(s): Embrapa Amazônia Ocidental. |
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| 58. | | AMELUNG, W.; MARTIUS, C.; GARCIA, M. V.; KUEPER, U.; ULBRICH, D.; ZECH, W. Organic matter in termite mounds of an Amazonian rain forest. In: SHIFT - WORKSHOP, 3., 1998, Manaus. Proceedings... Bonn: BMBF, 1998. p. 493-496.| Tipo: Artigo em Anais de Congresso |
| Biblioteca(s): Embrapa Amazônia Ocidental. |
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| 59. | | 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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| Registros recuperados : 86 | |
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