|
|
Registros recuperados : 62 | |
21. | | LILIENFEIN, J.; WILCKE, W.; AYARZA, M. A.; LIMA, S. do C.; VILELA, L.; ZECH, W. Annual course of matric potential in differently used savanna oxisols in Brazil. Soil Society of American Journal, Madison, v.63, p.1778-1785, 1999. Biblioteca(s): Embrapa Cerrados. |
| |
24. | | RAMOS, A. K. B.; PIZARRO, E. A.; AYARZA, M. A.; CARVALHO, M. A.; COSTA, P. H. Avaliacao agronomica de gramineas forrageiras consorciadas com Stylosanthes guianensis Cv. Mineirao em Uberlandia - MG. In: REUNIAO ANUAL DA SOCIEDADE BRASILEIRA DE ZOOTECNIA, 33., 1996, Fortaleza, CE. Anais... Fortaleza: SBZ, 1996. v.2. p.206-208. Biblioteca(s): Embrapa Cerrados. |
| |
25. | | PIZARRO, E. A.; RAMOS, A. K. B.; AYARZA, M. A.; CARVALHO, M. A.; COSTA, P. H. Avaliacao agronomica de leguminosas forrageiras consorciadas com B. decumbens em Uberlandia - MG. In: REUNIAO ANUAL DA SOCIEDADE BRASILEIRA DE ZOOTECNIA, 33., 1996, Fortaleza, CE. Anais... Fortaleza: SBZ, 1996. v.2. p.209-211. Biblioteca(s): Embrapa Cerrados. |
| |
26. | | WESTERHOF, R.; BUURMAN, P.; GRIETHUYSEN, C. van; AYARZA, M. A.; VILELA, L.; ZECH, W. Aggregation studied by laser diffraction in relation to plowing and liming in the Cerrado region in Brazil. Geoderma, Amsterdam, v.90, p.277-290, 1999. Biblioteca(s): Embrapa Cerrados. |
| |
27. | | WESTERHOF, R.; BUURMAN, P.; GRIETHUYSEN, C. van; AYARZA, M. A.; VILELA, L.; ZECH, W. Aggregation studied by laser diffraction in relation to plowing, soil organic matter, and lime 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.64-76. Biblioteca(s): Embrapa Cerrados. |
| |
28. | | LILIENFEIN, J.; WILCKE, W.; AYARZA, M. A.; VILELA, L.; LIMA, S. do C.; ZECH, W. Chemical fractionation of phosphorus, sulphur, and molybdenum in Brazilian savannah oxisols under different land use. Geoderma, Amsterdam, v. 96, p. 31-46, 2000. Biblioteca(s): Embrapa Cerrados. |
| |
29. | | THOMAS, R. J.; FISHER, M.; LASCANO, C.; RAO, I. M.; AYARZA, M.; ASAKAWA, N. Nutrient cycling via forage litter in tropical grass-legume pastures. In: Proceedings of the XVII International Grassland Congress, New Zealand., v., p.508-509, 1994. Biblioteca(s): Embrapa Agrobiologia. |
| |
32. | | 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. |
| |
34. | | ARAUJO, A. G. de; AYARZA, M. A.; FRIESEN, D. K.; VILELA, L. Fracoes organicas e inorganicas de fosforo em um solo de cerrado sob diferentes sistemas de manejo. 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.319-322. Biblioteca(s): Embrapa Cerrados. |
| |
35. | | ARAÚJO, A. G. de; AYARZA, M. A.; FRIESEN, D. K.; VILELA, L. Frações orgânicas e inorgânicas de fósforo em um solo de cerrado sob diferentes sistemas de manejo. In: SIMPÓSIO SOBRE O CERRADO, 8.; INTERNATIONAL SYMPOSIUM ON TROPICAL SAVANNAS, 1., 1996, Brasília, DF. Biodiversidade e produção sustentável de alimentos e fibras nos cerrados: anais. Planaltina, DF: EMBRAPA-CPAC, 1996. p. 319-322. Biblioteca(s): Embrapa Meio Norte / UEP-Parnaíba. |
| |
36. | | LILIENFEIN, J.; WILCKE, W.; AYARZA, M. A.; VILELA, L.; LIMA, S. do C.; ZECK, W. Soil acidification in Pinus caribaea forests on Brazilian savanna oxisols. Forest Ecology and Management, Amsterdam, v. 128, p. 145-157, 2000. Biblioteca(s): Embrapa Cerrados. |
| |
37. | | 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. |
| |
39. | | AYARZA, M. A.; VILELA, L.; PIZARRO, E. A.; COSTA, P. H. da. Sistemas agropastoriles basados en leguminosas de usos multiples. In: GUIMARAES, E.P.; SANZ, J.I.; RAO, I.M.; AMEZQUITA, M.C.; AMEZQUITA, E., ed. Sistemas agropastoriles en sabanas tropicales de America Latina. Cali: CIAT/Brasilia: Embrapa, 1999. p.175-193. Biblioteca(s): Embrapa Cerrados. |
| |
Registros recuperados : 62 | |
|
|
| Acesso ao texto completo restrito à biblioteca da Embrapa Cerrados. Para informações adicionais entre em contato com cpac.biblioteca@embrapa.br. |
Registro Completo
Biblioteca(s): |
Embrapa Cerrados. |
Data corrente: |
15/07/1999 |
Data da última atualização: |
15/07/1999 |
Autoria: |
NEUFELDT, H.; AYARZA, M. A.; RESCK, D. V. S.; ZECH, W. |
Título: |
Distribution of water-stable aggregates and aggregating agents in oxisols of the Brazilian cerrados. |
Ano de publicação: |
1999 |
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. |
Páginas: |
p.51-63. |
Idioma: |
Inglês |
Conteúdo: |
The effects of land-use change on the structure of Oxisols in the Brazilian savannas (also known as the Cerrados) are still insuficiently understood. We therefore studied loamy and clayey Oxisols under natural savanna, crop, pastures, and reforestation to (1) quantify management-induced changes in the quantity of water-stable aggregates, (2) identify the main aggregating agents, and (3) correlate aggregation with changes in pore-size distribution. Clayey soils showed a significantly higher macroaggregation than did loamy soils. Compared with natural savanna, macroaggregation was clearly reduced under crops, whereas aggregation of soils under pasture and tree plantations was only slightly affected. In both clavey and loamy soils, polysaccharides formed the main aggregating agent. In the clayey soils, lime very effectively disaggregated the soils by weakening the electrostatic forces between positivily and negatively charged soil compounds. In the loamy soils, the role of roots in binding macroaggregates was significant. Because pastures provide strong rooting and higt polysaccharide production, we recommend introducing crop/pasture rotations. Management-induced disaggregation strongly affected the pore-size distribution by compacting the soils, and thus reducing macroporosity and increasing mesoporosity. Microporosity, however, was unaffected by management and differed only between the two substrates. Considering the Oxisols' typically low pore space at plant-available matrix potentials, the increase in mesoporosity may be important for annual crops during the frequent dry spells in the rainy season. MenosThe effects of land-use change on the structure of Oxisols in the Brazilian savannas (also known as the Cerrados) are still insuficiently understood. We therefore studied loamy and clayey Oxisols under natural savanna, crop, pastures, and reforestation to (1) quantify management-induced changes in the quantity of water-stable aggregates, (2) identify the main aggregating agents, and (3) correlate aggregation with changes in pore-size distribution. Clayey soils showed a significantly higher macroaggregation than did loamy soils. Compared with natural savanna, macroaggregation was clearly reduced under crops, whereas aggregation of soils under pasture and tree plantations was only slightly affected. In both clavey and loamy soils, polysaccharides formed the main aggregating agent. In the clayey soils, lime very effectively disaggregated the soils by weakening the electrostatic forces between positivily and negatively charged soil compounds. In the loamy soils, the role of roots in binding macroaggregates was significant. Because pastures provide strong rooting and higt polysaccharide production, we recommend introducing crop/pasture rotations. Management-induced disaggregation strongly affected the pore-size distribution by compacting the soils, and thus reducing macroporosity and increasing mesoporosity. Microporosity, however, was unaffected by management and differed only between the two substrates. Considering the Oxisols' typically low pore space at plant-available matrix... Mostrar Tudo |
Thesagro: |
Cerrado; Estrutura do Solo; Oxisol; Uso da Terra. |
Thesaurus NAL: |
Ferralsols; land use; soil structure. |
Categoria do assunto: |
-- |
Marc: |
LEADER 02445naa a2200253 a 4500 001 1545398 005 1999-07-15 008 1999 bl uuuu u00u1 u #d 100 1 $aNEUFELDT, H. 245 $aDistribution of water-stable aggregates and aggregating agents in oxisols of the Brazilian cerrados. 260 $c1999 300 $ap.51-63. 520 $aThe effects of land-use change on the structure of Oxisols in the Brazilian savannas (also known as the Cerrados) are still insuficiently understood. We therefore studied loamy and clayey Oxisols under natural savanna, crop, pastures, and reforestation to (1) quantify management-induced changes in the quantity of water-stable aggregates, (2) identify the main aggregating agents, and (3) correlate aggregation with changes in pore-size distribution. Clayey soils showed a significantly higher macroaggregation than did loamy soils. Compared with natural savanna, macroaggregation was clearly reduced under crops, whereas aggregation of soils under pasture and tree plantations was only slightly affected. In both clavey and loamy soils, polysaccharides formed the main aggregating agent. In the clayey soils, lime very effectively disaggregated the soils by weakening the electrostatic forces between positivily and negatively charged soil compounds. In the loamy soils, the role of roots in binding macroaggregates was significant. Because pastures provide strong rooting and higt polysaccharide production, we recommend introducing crop/pasture rotations. Management-induced disaggregation strongly affected the pore-size distribution by compacting the soils, and thus reducing macroporosity and increasing mesoporosity. Microporosity, however, was unaffected by management and differed only between the two substrates. Considering the Oxisols' typically low pore space at plant-available matrix potentials, the increase in mesoporosity may be important for annual crops during the frequent dry spells in the rainy season. 650 $aFerralsols 650 $aland use 650 $asoil structure 650 $aCerrado 650 $aEstrutura do Solo 650 $aOxisol 650 $aUso da Terra 700 1 $aAYARZA, M. A. 700 1 $aRESCK, D. V. S. 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.
Download
Esconder MarcMostrar Marc Completo |
Registro original: |
Embrapa Cerrados (CPAC) |
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
Fechar
|
Nenhum registro encontrado para a expressão de busca informada. |
|
|