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 | Acesso ao texto completo restrito à biblioteca da Embrapa Amazônia Oriental. Para informações adicionais entre em contato com cpatu.biblioteca@embrapa.br. |
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Registro Completo |
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Biblioteca(s): |
Embrapa Amazônia Oriental. |
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Data corrente: |
28/01/2008 |
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Data da última atualização: |
23/11/2022 |
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Tipo da produção científica: |
Artigo em Periódico Indexado |
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Autoria: |
GARCIA-MONTIEL, D. C.; COE, M. T.; CRUZ, M. P.; FERREIRA, J. N.; SILVA, E. M. da. |
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Afiliação: |
Diana C. Garcia-Montiel, UNB; Michael T. Coe, The woods Hole Research Center; Meyr P. Cruz, UNB; JOICE NUNES FERREIRA, CPATU; Euzebio M. da Silva, CPAC. |
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Título: |
Estimating seasonal changes in volumetric soil water content at landscape scales in a savanna ecosystem using two-dimensional resistivity profiling. |
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Ano de publicação: |
2008 |
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Fonte/Imprenta: |
Earth Interactions, v. 12, n. 2, p. 1-25, Mar. 2008. |
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DOI: |
http://dx.doi.org/10.1175/2007EI238.1 |
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Idioma: |
Inglês |
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Conteúdo: |
Water distributed in deep soil reservoirs is an important factor determining the ecosystem structure of water-limited environments, such as the seasonal tropical savannas of South America. In this study a two-dimensional (2D) geoelectrical profiling technique was employed to estimate seasonal dynamics of soil water content to 10-m depth along transects of 275 m in savanna vegetation during the period between 2002 and 2006. Methods were developed to convert resistivity values along these 2D resistivity profiles into volumetric water content (VWC) by soil depth. The 2D resistivity profiles revealed the following soil and aquifer structure characterizing the underground environment: 0?4 m of permanently unsaturated and seasonally droughty soil, less severely dry unsaturated soil at about 4?7 m, nearly permanently saturated soil between 7 and 10 m, mostly impermeable saprolite interspaced with fresh bedrock of parent material at about 10?30 m, and a region of highly conductive water-saturated material at 30 m and below. Considerable spatial variation of these relative depths is clearly demonstrated along the transects. Temporal dynamics in VWC indicate that the active zone of water uptake is predominantly at 0?7 m, and follows the seasonal cycles of precipitation and evapotranspiration. Uptake from below 7 m may have been critical for a short period near the beginning of the rainy season, although the seasonal variations in VWC in the 7?10-m layer are relatively small and lag the surface water recharge for about 6 months. Calculations using a simple 1-box water balance model indicate that average total runoff was 15?25 mm month?1 in the wet season and about 6?9 mm month?1 in the dry season. Modeled ET was about 75?85 mm month?1 in the wet season and 20?25 mm month?1 in the dry season. Variation in basal area and tree density along one transect was positively correlated with VWC of the 0?3-m and 0?7-m soil depths, respectively, during the wettest months. These multitemporal measurements demonstrate that the along-transect spatial differences in soil moisture are quasi-permanent and influence vegetation structure at the scale of tens to hundreds of meters. MenosWater distributed in deep soil reservoirs is an important factor determining the ecosystem structure of water-limited environments, such as the seasonal tropical savannas of South America. In this study a two-dimensional (2D) geoelectrical profiling technique was employed to estimate seasonal dynamics of soil water content to 10-m depth along transects of 275 m in savanna vegetation during the period between 2002 and 2006. Methods were developed to convert resistivity values along these 2D resistivity profiles into volumetric water content (VWC) by soil depth. The 2D resistivity profiles revealed the following soil and aquifer structure characterizing the underground environment: 0?4 m of permanently unsaturated and seasonally droughty soil, less severely dry unsaturated soil at about 4?7 m, nearly permanently saturated soil between 7 and 10 m, mostly impermeable saprolite interspaced with fresh bedrock of parent material at about 10?30 m, and a region of highly conductive water-saturated material at 30 m and below. Considerable spatial variation of these relative depths is clearly demonstrated along the transects. Temporal dynamics in VWC indicate that the active zone of water uptake is predominantly at 0?7 m, and follows the seasonal cycles of precipitation and evapotranspiration. Uptake from below 7 m may have been critical for a short period near the beginning of the rainy season, although the seasonal variations in VWC in the 7?10-m layer are relatively small and lag th... Mostrar Tudo |
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Thesagro: |
Água; Cerrado; Ecossistema. |
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Categoria do assunto: |
P Recursos Naturais, Ciências Ambientais e da Terra |
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Marc: |
LEADER 02895naa a2200217 a 4500
001 1409265
005 2022-11-23
008 2008 bl uuuu u00u1 u #d
024 7 $ahttp://dx.doi.org/10.1175/2007EI238.1$2DOI
100 1 $aGARCIA-MONTIEL, D. C.
245 $aEstimating seasonal changes in volumetric soil water content at landscape scales in a savanna ecosystem using two-dimensional resistivity profiling.$h[electronic resource]
260 $c2008
520 $aWater distributed in deep soil reservoirs is an important factor determining the ecosystem structure of water-limited environments, such as the seasonal tropical savannas of South America. In this study a two-dimensional (2D) geoelectrical profiling technique was employed to estimate seasonal dynamics of soil water content to 10-m depth along transects of 275 m in savanna vegetation during the period between 2002 and 2006. Methods were developed to convert resistivity values along these 2D resistivity profiles into volumetric water content (VWC) by soil depth. The 2D resistivity profiles revealed the following soil and aquifer structure characterizing the underground environment: 0?4 m of permanently unsaturated and seasonally droughty soil, less severely dry unsaturated soil at about 4?7 m, nearly permanently saturated soil between 7 and 10 m, mostly impermeable saprolite interspaced with fresh bedrock of parent material at about 10?30 m, and a region of highly conductive water-saturated material at 30 m and below. Considerable spatial variation of these relative depths is clearly demonstrated along the transects. Temporal dynamics in VWC indicate that the active zone of water uptake is predominantly at 0?7 m, and follows the seasonal cycles of precipitation and evapotranspiration. Uptake from below 7 m may have been critical for a short period near the beginning of the rainy season, although the seasonal variations in VWC in the 7?10-m layer are relatively small and lag the surface water recharge for about 6 months. Calculations using a simple 1-box water balance model indicate that average total runoff was 15?25 mm month?1 in the wet season and about 6?9 mm month?1 in the dry season. Modeled ET was about 75?85 mm month?1 in the wet season and 20?25 mm month?1 in the dry season. Variation in basal area and tree density along one transect was positively correlated with VWC of the 0?3-m and 0?7-m soil depths, respectively, during the wettest months. These multitemporal measurements demonstrate that the along-transect spatial differences in soil moisture are quasi-permanent and influence vegetation structure at the scale of tens to hundreds of meters.
650 $aÁgua
650 $aCerrado
650 $aEcossistema
700 1 $aCOE, M. T.
700 1 $aCRUZ, M. P.
700 1 $aFERREIRA, J. N.
700 1 $aSILVA, E. M. da
773 $tEarth Interactions$gv. 12, n. 2, p. 1-25, Mar. 2008.
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Embrapa Amazônia Oriental (CPATU) |
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| 5. |  | GOMIDE, C. A. de M.; REIS, R. A.; FREITAS, D. Estrutura da pastagem de capim-marandu sob pastejo de lotação intermitente, em resposta a níveis de suplementação alimentar de novilhos. In: REUNIÃO ANUAL DA SOCIEDADE BRASILEIRA DE ZOOTECNIA, 41., 2004, Campo Grande, MS. Produção animal e a segurança alimentar: anais. Viçosa, MG: Sociedade Brasileira de Zootecnia, 2004.| Tipo: Artigo em Anais de Congresso |
| Biblioteca(s): Embrapa Gado de Leite. |
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| 9. | | REIS, R. A.; RODRIGUES, L. R. A.; RODRIGUES, A. de A.; VILELA, C. P.; ROSA, B. Avaliação de fontes de amônia para o tratamento de volumosos. In: REUNIÃO ANUAL DA SOCIEDADE BRASILEIRA DE ZOOTECNIA, 30., 1993, Rio de Janeiro, RJ. Anais... Rio de Janeiro: SBZ, 1993. p. 102.| Tipo: Resumo em Anais de Congresso |
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| 12. | | JOBIM, C. C.; REIS, R. A.; RODRIGUES, L. R. de A.; SCHOCKEN-ITURRINO, R.P. Presença de microrganismos na silagem de grãos úmidos de milho ensilado com diferentes proporções de sabugo. Pesquisa Agropecuária Brasileira, Brasília, DF, v. 32, n. 2, p. 201-204, fev. 1997. Título em inglês: Microorganisms in the high-moisture corn grain silage with different proportions of the cob.| Biblioteca(s): Embrapa Unidades Centrais. |
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| 14. | | FAVORETTO, V.; TONINI JUNIOR, R.; REIS, R. A.; RODRIGUES, L. R. de A. Efeito da altura e da frequencia de corte sobre a producao, composicao bromatologica e vigor de rebrota do capim-coloniao. Pesquisa Agropecuaria Brasileira, Brasilia, v.22, n.11/12, p.1279-1285, nov./dez/1987.| Biblioteca(s): Embrapa Unidades Centrais. |
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| 18. | | GOMIDE, C. A. de M.; REIS, R. A.; FREITAS, D.; MOREIRA, A. L. Morfogênese do capim-marandu sob lotação intermitente no período verão-outono conforme o nível de suplementação de novilhos. In: REUNIÃO ANUAL DA SOCIEDADE BRASILEIRA DE ZOOTECNIA, 41., 2004, Campo Grande, MS. Produção animal e a segurança alimentar: anais. Viçosa, MG: Sociedade Brasileira de Zootecnia, 2004.| Tipo: Artigo em Anais de Congresso |
| Biblioteca(s): Embrapa Gado de Leite. |
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| 19. | | GOMIDE, C. A. de M.; MOREIRA, A. L.; REIS, R. A.; SIMILI, F. F. Sobre-semeadura de espécies de inverno em pastagem de capim-Tifton 85: estrutura e produção da pastagem. In: REUNIÃO ANUAL DA SOCIEDADE BRASILEIRA DE ZOOTECNIA, 41., 2004, Campo Grande, MS. Produção animal e a segurança alimentar: anais. Viçosa, MG: Sociedade Brasileira de Zootecnia, 2004.| Tipo: Artigo em Anais de Congresso |
| Biblioteca(s): Embrapa Gado de Leite. |
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| 20. | | REIS, R. A.; RODRIGUES, L. R. A.; NAHAS, E.; BONJARDIM, S. R.; PEREIRA, J. R. A. P. Amonização do Feno de Brachiaria Decumbens com Diferentes Teores de Umidade. Pesquisa Agropecuaria Brasileira, Brasilia, v.28, n.4, p.539-543,abr.1993| Biblioteca(s): Embrapa Unidades Centrais. |
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| Registros recuperados : 70 | |
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