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Registro Completo |
Biblioteca(s): |
Embrapa Amazônia Ocidental. |
Data corrente: |
20/05/1999 |
Data da última atualização: |
04/04/2022 |
Tipo da produção científica: |
Capítulo em Livro Técnico-Científico |
Autoria: |
SCHROTH, G.; SALAZAR, E.; SILVA JUNIOR, J. P. da; SEIXAS, R.; MACEDO, J. L. V. de. |
Afiliação: |
JOSE PEREIRA DA SILVA JUNIOR, CPAA; JEFERSON LUIS VASCONCELOS DE MACEDO, CPAA. |
Título: |
Spatial and temporal patterns of N availability and N mineralization under tree crops and a cover crop in a multi-strata agroforestry system of central Amazonia. |
Ano de publicação: |
1999 |
Fonte/Imprenta: |
In: SHIFT PROJECT ENV 23 (Manaus-AM). Recuperacao de areas degradadas e abandonadas, atraves de sistemas de policultivo. Manaus: Embrapa Amazônia Ocidental, 1999. |
Páginas: |
p. 58-89. |
Idioma: |
Inglês |
Notas: |
Relatório Anual 1998. |
Conteúdo: |
Under rainforest vegetation, the Oxisols and Ultisols which dominate Amazonian uplands are characterized by relatively high availability of N in relation to other nutrients. When the rainforest vegetation is converted into agricultural systems, the disruption of the nutrient recycling mechanisms of the forest under conditions of intensive rainfalls and permeable soils increases the potencial for N leaching. In a previous study, substantial amounts of mineral N were found in the subsoil of central Amazonia Oxisol under various tree crops and a legumenous cover crops, indicating that even under perennial cropping systems, much of the mineralized soil and fertilizer N may be lost unproductively. We hypothesized that the spatial and temporal patterns of N availability and N mineralization in the soil of a polycultural system would influence the efficiency with which N is taken up by the trees instead of being leached. The analysis of such pattens coul lead to strategies for improving this efficiency and reducing the dependence of the system on external nutrient inputs. The concentration of mineral N and the net N mineralization in the topsoil were measured at five occasions during 10 months in a multi-strata agroforestry system on an Oxisol in central Amazonia, Brazil. The system was composed of three tree crop species and a leguminous cover crop, and was studied at two fertilization levels. The net N mineralization was highest under the cover crop, intermediate under a tree crop where the soil was also covered by the cover crop. This resulted in higher mineral N concentrations in the soil under the cover crop than under the tree crops during part of the rainy season. The increased N mineralization under the cover crop was due to higher total N in the soil, higher soil moisture and presumably a larger pool of readily mineralizable N components in the soil compared to the tree crops. Other fertility parameters also differed significantly between sampling positions within the plots, but this had no major influence on net N mineralization. Also, the fertilization level had no significant influence on N mineralization. As most of the N was mineralized under the cover crop at some distance from the trees, the uptake of the mineralized N by the tree crops could presumably be increased, and N leaching reduced, by a higher tree density and an altered management of the cover crop to increase N mineralization in the soil close to the trees. In view of the high total N mineralization rates in the system (349 kg ha-1 yr-1) and unclear yield responses of the tree crops to N fertilization at this site, it is concluded that after an establishment phase, the fertilization with N of tree crops with well-developed root systems may not always be necessary on this soil type. MenosUnder rainforest vegetation, the Oxisols and Ultisols which dominate Amazonian uplands are characterized by relatively high availability of N in relation to other nutrients. When the rainforest vegetation is converted into agricultural systems, the disruption of the nutrient recycling mechanisms of the forest under conditions of intensive rainfalls and permeable soils increases the potencial for N leaching. In a previous study, substantial amounts of mineral N were found in the subsoil of central Amazonia Oxisol under various tree crops and a legumenous cover crops, indicating that even under perennial cropping systems, much of the mineralized soil and fertilizer N may be lost unproductively. We hypothesized that the spatial and temporal patterns of N availability and N mineralization in the soil of a polycultural system would influence the efficiency with which N is taken up by the trees instead of being leached. The analysis of such pattens coul lead to strategies for improving this efficiency and reducing the dependence of the system on external nutrient inputs. The concentration of mineral N and the net N mineralization in the topsoil were measured at five occasions during 10 months in a multi-strata agroforestry system on an Oxisol in central Amazonia, Brazil. The system was composed of three tree crop species and a leguminous cover crop, and was studied at two fertilization levels. The net N mineralization was highest under the cover crop, intermediate under a tree cro... Mostrar Tudo |
Palavras-Chave: |
Agrofloresta; Amazonas; Brasil; Manaus. |
Thesagro: |
Cultivo Multiplo; Fertilidade do Solo; Floresta Tropical Úmida; Nitrogênio; Solo. |
Thesaurus Nal: |
agroforestry; multiple cropping; nitrogen; nitrogen fertilizers; soil; soil fertility; tropical rain forests. |
Categoria do assunto: |
-- |
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/181178/1/ID-4037-2-47-72.pdf
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Marc: |
LEADER 04017naa a2200385 a 4500 001 1668177 005 2022-04-04 008 1999 bl uuuu u00u1 u #d 100 1 $aSCHROTH, G. 245 $aSpatial and temporal patterns of N availability and N mineralization under tree crops and a cover crop in a multi-strata agroforestry system of central Amazonia. 260 $c1999 300 $ap. 58-89. 500 $aRelatório Anual 1998. 520 $aUnder rainforest vegetation, the Oxisols and Ultisols which dominate Amazonian uplands are characterized by relatively high availability of N in relation to other nutrients. When the rainforest vegetation is converted into agricultural systems, the disruption of the nutrient recycling mechanisms of the forest under conditions of intensive rainfalls and permeable soils increases the potencial for N leaching. In a previous study, substantial amounts of mineral N were found in the subsoil of central Amazonia Oxisol under various tree crops and a legumenous cover crops, indicating that even under perennial cropping systems, much of the mineralized soil and fertilizer N may be lost unproductively. We hypothesized that the spatial and temporal patterns of N availability and N mineralization in the soil of a polycultural system would influence the efficiency with which N is taken up by the trees instead of being leached. The analysis of such pattens coul lead to strategies for improving this efficiency and reducing the dependence of the system on external nutrient inputs. The concentration of mineral N and the net N mineralization in the topsoil were measured at five occasions during 10 months in a multi-strata agroforestry system on an Oxisol in central Amazonia, Brazil. The system was composed of three tree crop species and a leguminous cover crop, and was studied at two fertilization levels. The net N mineralization was highest under the cover crop, intermediate under a tree crop where the soil was also covered by the cover crop. This resulted in higher mineral N concentrations in the soil under the cover crop than under the tree crops during part of the rainy season. The increased N mineralization under the cover crop was due to higher total N in the soil, higher soil moisture and presumably a larger pool of readily mineralizable N components in the soil compared to the tree crops. Other fertility parameters also differed significantly between sampling positions within the plots, but this had no major influence on net N mineralization. Also, the fertilization level had no significant influence on N mineralization. As most of the N was mineralized under the cover crop at some distance from the trees, the uptake of the mineralized N by the tree crops could presumably be increased, and N leaching reduced, by a higher tree density and an altered management of the cover crop to increase N mineralization in the soil close to the trees. In view of the high total N mineralization rates in the system (349 kg ha-1 yr-1) and unclear yield responses of the tree crops to N fertilization at this site, it is concluded that after an establishment phase, the fertilization with N of tree crops with well-developed root systems may not always be necessary on this soil type. 650 $aagroforestry 650 $amultiple cropping 650 $anitrogen 650 $anitrogen fertilizers 650 $asoil 650 $asoil fertility 650 $atropical rain forests 650 $aCultivo Multiplo 650 $aFertilidade do Solo 650 $aFloresta Tropical Úmida 650 $aNitrogênio 650 $aSolo 653 $aAgrofloresta 653 $aAmazonas 653 $aBrasil 653 $aManaus 700 1 $aSALAZAR, E. 700 1 $aSILVA JUNIOR, J. P. da 700 1 $aSEIXAS, R. 700 1 $aMACEDO, J. L. V. de 773 $tIn: SHIFT PROJECT ENV 23 (Manaus-AM). Recuperacao de areas degradadas e abandonadas, atraves de sistemas de policultivo. Manaus: Embrapa Amazônia Ocidental, 1999.
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Registro original: |
Embrapa Amazônia Ocidental (CPAA) |
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Registros recuperados : 130 | |
23. | | DE BONA, F. D.; SANTI, A.; SILVA JUNIOR, J. P. da; WIETHÖLTER, S. Calagem, adubação de base e inoculação em sementes. In: DE MORI, C.; ANTUNES, J. M.; FAE, G. S.; ACOSTA, A. da S. (Ed.). Trigo: o produtor pergunta, a Embrapa responde. Cap. 4, p. 85-104. Brasília, DF: Embrapa, 2016.Tipo: Capítulo em Livro Técnico-Científico |
Biblioteca(s): Embrapa Trigo. |
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24. | | SILVA, F. V.; ARAÚJO, J. L. S. de; RUMJANEK, N. G.; SILVA JÚNIOR, J. P. Caracterização de Bradyrhizobium da região amazônica por ardra e sequenciamento do 16S rDNA. In: ENCONTRO NACIONAL DE MICROBIOLOGIA AMBIENTAL, 11., SIMPÓSIO BRASILEIRO DE MICROBIOLOGIA DO SOLO, 10., 2008, Fortaleza. Resumos... Fortaleza, 2008.Tipo: Artigo em Anais de Congresso / Nota Técnica |
Biblioteca(s): Embrapa Agrobiologia. |
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28. | | GRAHL, M. A.; SILVA JUNIOR, J. P. da; CASTRO, R. L. de. Reação de cultivares e linhagens promissoras de trigo ao Alumínio no solo. In: MOSTRA DE INICIAÇÃO CIENTÍFICA, 15.; MOSTRA DE PÓS-GRADUAÇÃO DA EMBRAPA TRIGO, 12., 2020, Passo Fundo. Resumos... Brasília, DF: Embrapa, p. 43, 2021.Tipo: Resumo em Anais de Congresso |
Biblioteca(s): Embrapa Trigo. |
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29. | | MINOZZO, J. A. D.; AGUILERA, J. G.; CONSOLI, L.; SILVA JUNIOR, J. P. da. Reação a níveis crescentes de alumínio (Al3+) de genótipos de trigo com diferentes promotores (TaALMT1 e TaMATE1B). In: MOSTRA DE INICIAÇÃO CIENTÍFICA, 11.; MOSTRA DE PÓS-GRADUAÇÃO DA EMBRAPA TRIGO, 8., 2016, Passo Fundo. Resumos... Brasília, DF: Embrapa, 2016. p. 42.Tipo: Resumo em Anais de Congresso |
Biblioteca(s): Embrapa Trigo. |
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32. | | ZEM, G.; CASTRO, R. L. de; SILVA JUNIOR, J. P. da; CONSOLI, L.; CAIERAO, E. Resposta de cultivares de trigo à inoculação com Azospirillum brasilense em Passo Fundo, ano 2012. In: MOSTRA DE INICIAÇÃO CIENTÍFICA DA EMBRAPA TRIGO, 8.; MOSTRA DE PÓS-GRADUAÇÃO DA EMBRAPA TRIGO, 5., 2013, Passo Fundo. Resumos... Brasília, DF: Embrapa, 2013. p. 44. Editores técnicos: Joseani Mesquita Antunes, Ana Lídia Variani Bonato, Márcia Barrocas Moreira Pimentel.Tipo: Resumo em Anais de Congresso |
Biblioteca(s): Embrapa Trigo. |
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38. | | WIETHÖLTER, S.; SCHEEREN, P. L.; CAIERÃO, E.; GUARIENTI, E. M.; SILVA JUNIOR, J. P. da. Efeito da aplicação de nitrogênio ao solo na qualidade do grão e no rendimento de cultivares de trigo. In: CONGRESSO BRASILEIRO DE CIÊNCIA DO SOLO, 31., 2007, Gramado. Livro de resumos... Porto Alegre: SBCS, Núcleo Regional Sul, 2007. p. 20. Resumo 084-6714.Tipo: Resumo em Anais de Congresso |
Biblioteca(s): Embrapa Trigo. |
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Registros recuperados : 130 | |
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Nenhum registro encontrado para a expressão de busca informada. |
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