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| 12. |  | SILVA, S. C. da; CASTRO, V. F. Analogia entre métodos para estimativa da evapotranspiração de referencia (ETo), para Goiânia-GO, utilizando os dados meteorológicos, médias mensais, referente ao período de 1983 a 1994, considerando-se o método de Penman-Monteith como padrão. In: CONGRESSO BRASILEIRO DE AGROMETEOROLOGIA, 9., 1995, Campina Grande, PB. Anais: adversidade climaticas e a producao agricola. Campina Grande: SBA, 1995. p. 212-214.| Biblioteca(s): Embrapa Arroz e Feijão; Embrapa Cerrados; Embrapa Tabuleiros Costeiros. |
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 | Acesso ao texto completo restrito à biblioteca da Embrapa Gado de Corte. Para informações adicionais entre em contato com cnpgc.biblioteca@embrapa.br. |
Registro Completo
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Biblioteca(s): |
Embrapa Gado de Corte. |
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Data corrente: |
16/06/2004 |
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Data da última atualização: |
07/12/2010 |
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Autoria: |
MIRANDA, C. H. B.; MACEDO, M. C. M.; KANDA, K.; NAKAMURA, T. |
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Afiliação: |
Embrapa Gado de Corte (Campo Grande, MS). |
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Título: |
Soil organic residues accumulation in agro-pastoral systems in the cerrados of Brazil. |
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Ano de publicação: |
2004 |
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Fonte/Imprenta: |
In: SUENAGA, K.; OSHIBE, A.; TANIGUHI, T. (Ed.). Development of sustainable agro-pastoral systems in the subtropical zone of Brazil. Tsukuba: JIRCAS, 2004. |
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Páginas: |
p. 29-33. |
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Série: |
(JIRCAS. Working Report, 36). |
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Idioma: |
Inglês |
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Notas: |
CNPGC. Proceedings of the Workshop on the results and prospects of comprehensive studies on the development of sustainable agro-pastoral systems in the subtropical zone of Brazil, 2003. |
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Conteúdo: |
Soil samples were collected in February, 2002, from 0-10, 10-20 and 20-40cm soil depth layers, in a 20x20cm randomized soil cores, within eight production systems introduced in 1993/94. Eight replicates were collected in each plot. They encompassed continuous grazing pastures, continuous soybean plots under contrasting soil preparation (conventional, minimum or zero tillage), and their rotation with grazing pastures. Comparisons were made with a Cerrados undisturbed plot and a degraded pasture. A physical separation of soil organic residues was made in the lab passing 5kg of dry soil throughout sieves with 2.0mm mesh (fresh light fraction).0,25mm (light fraction), or 0,105mm (heavy fraction). Soil was also analysed for its total Carbon content and 13C natural abundance. Most of the organic residues accumulates on the 0-10cm depth. Compared to the native Cerrados, the introduction of a B.decumbens pasture in 1978 and its consequent degradation led to a sharp decrease in soil organic residues, specially in the layers up to 20cm depth. The renewal and fertilisation of the degraded pasture in 1993 stopped further decrease, and incrased the total amount of residues but reaching, on average, only 65% of those shown by the Cerrados. Soil continuously ultivated with soybean under a convencional system showed a decrease wven larger than the degraded pasture, while soil under minimum or zero tillage with soybean showed total amounts close to the degraded pasture. Soil 13C allowed to estimate that after 26 years of clearing the Cerrados and introducing pasture, 67% of the soil C from the original Cerrados was substituted by C originated from the pasture in the 0-1-cm depth layer. It decreases to 42 and 25% in the 10-20 and 20-40cm depthlayer, respectively. In soybean cultivated areas, however, only 21 to 30% (0-10cm depth), 11 to 17% (10-20cm depth), and less than 1% (20-40cm depth) of the original Cerrados C was substituted by soybean originated C. A slightly increase was observed in soil under zero tillage soybean in comparison to conventional and minimum tillage systems. MenosSoil samples were collected in February, 2002, from 0-10, 10-20 and 20-40cm soil depth layers, in a 20x20cm randomized soil cores, within eight production systems introduced in 1993/94. Eight replicates were collected in each plot. They encompassed continuous grazing pastures, continuous soybean plots under contrasting soil preparation (conventional, minimum or zero tillage), and their rotation with grazing pastures. Comparisons were made with a Cerrados undisturbed plot and a degraded pasture. A physical separation of soil organic residues was made in the lab passing 5kg of dry soil throughout sieves with 2.0mm mesh (fresh light fraction).0,25mm (light fraction), or 0,105mm (heavy fraction). Soil was also analysed for its total Carbon content and 13C natural abundance. Most of the organic residues accumulates on the 0-10cm depth. Compared to the native Cerrados, the introduction of a B.decumbens pasture in 1978 and its consequent degradation led to a sharp decrease in soil organic residues, specially in the layers up to 20cm depth. The renewal and fertilisation of the degraded pasture in 1993 stopped further decrease, and incrased the total amount of residues but reaching, on average, only 65% of those shown by the Cerrados. Soil continuously ultivated with soybean under a convencional system showed a decrease wven larger than the degraded pasture, while soil under minimum or zero tillage with soybean showed total amounts close to the degraded pasture. Soil 13C... Mostrar Tudo |
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Palavras-Chave: |
Agropastoral systems; Brasil; Brazilian savannas; Integração agricultura pecuária; Soils. |
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Thesagro: |
Cerrado; Resíduo Orgânico; Solo. |
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Thesaurus NAL: |
Brazil; crop residues. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 03248naa a2200313 a 4500
001 1325529
005 2010-12-07
008 2004 bl uuuu u00u1 u #d
100 1 $aMIRANDA, C. H. B.
245 $aSoil organic residues accumulation in agro-pastoral systems in the cerrados of Brazil.
260 $c2004
300 $ap. 29-33.
490 $a(JIRCAS. Working Report, 36).
500 $aCNPGC. Proceedings of the Workshop on the results and prospects of comprehensive studies on the development of sustainable agro-pastoral systems in the subtropical zone of Brazil, 2003.
520 $aSoil samples were collected in February, 2002, from 0-10, 10-20 and 20-40cm soil depth layers, in a 20x20cm randomized soil cores, within eight production systems introduced in 1993/94. Eight replicates were collected in each plot. They encompassed continuous grazing pastures, continuous soybean plots under contrasting soil preparation (conventional, minimum or zero tillage), and their rotation with grazing pastures. Comparisons were made with a Cerrados undisturbed plot and a degraded pasture. A physical separation of soil organic residues was made in the lab passing 5kg of dry soil throughout sieves with 2.0mm mesh (fresh light fraction).0,25mm (light fraction), or 0,105mm (heavy fraction). Soil was also analysed for its total Carbon content and 13C natural abundance. Most of the organic residues accumulates on the 0-10cm depth. Compared to the native Cerrados, the introduction of a B.decumbens pasture in 1978 and its consequent degradation led to a sharp decrease in soil organic residues, specially in the layers up to 20cm depth. The renewal and fertilisation of the degraded pasture in 1993 stopped further decrease, and incrased the total amount of residues but reaching, on average, only 65% of those shown by the Cerrados. Soil continuously ultivated with soybean under a convencional system showed a decrease wven larger than the degraded pasture, while soil under minimum or zero tillage with soybean showed total amounts close to the degraded pasture. Soil 13C allowed to estimate that after 26 years of clearing the Cerrados and introducing pasture, 67% of the soil C from the original Cerrados was substituted by C originated from the pasture in the 0-1-cm depth layer. It decreases to 42 and 25% in the 10-20 and 20-40cm depthlayer, respectively. In soybean cultivated areas, however, only 21 to 30% (0-10cm depth), 11 to 17% (10-20cm depth), and less than 1% (20-40cm depth) of the original Cerrados C was substituted by soybean originated C. A slightly increase was observed in soil under zero tillage soybean in comparison to conventional and minimum tillage systems.
650 $aBrazil
650 $acrop residues
650 $aCerrado
650 $aResíduo Orgânico
650 $aSolo
653 $aAgropastoral systems
653 $aBrasil
653 $aBrazilian savannas
653 $aIntegração agricultura pecuária
653 $aSoils
700 1 $aMACEDO, M. C. M.
700 1 $aKANDA, K.
700 1 $aNAKAMURA, T.
773 $tIn: SUENAGA, K.; OSHIBE, A.; TANIGUHI, T. (Ed.). Development of sustainable agro-pastoral systems in the subtropical zone of Brazil. Tsukuba: JIRCAS, 2004.
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