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Registro Completo |
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Biblioteca(s): |
Embrapa Hortaliças; Embrapa Pantanal. |
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Data corrente: |
12/03/1996 |
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Data da última atualização: |
19/07/2018 |
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Autoria: |
SILVA, H. R. |
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Afiliação: |
Utah State University (Logan, Utah). |
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Título: |
Wetting-induced changes in near surface soil physical properties affecting surface irrigation. |
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Ano de publicação: |
1995 |
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Fonte/Imprenta: |
Logan: Utah State University, 1995. |
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Páginas: |
188p.il. |
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Idioma: |
Inglês |
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Notas: |
Ph.D. Dissertation. |
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Conteúdo: |
Intermittent application of water into many soils produces changes in soil structure and hydraulic properties, resulting in faster advance with less volume of applied water as compared with continuous application. Two distinct soils, a Millville silt loam and a Red-yellow oxisol, were used to study the susceptibility of soil structure to the effects of wetting and drying. Ethanol was used to characterize the condition prior to water application and to distinguish between effects of wetting and drying (by water) on the structure of an unstable soil. The objective of this study was to quantify and show structural changes that affect soil hydraulic properties. Air entrapment effects on infiltration processes during intermittent and continuous water application were also studied. Laboratory and field experiments were carried out to achieve the objectives of this study. Important aspects of soil structural changes were identifyied by measurements with water and ethanol. The major changes were (a) reduction in porosity and (b) pore size distribution. Results reconfirmed that intermittent application of water is an efficiency way to decrease intake rates. An accentuated reduction in intake during the first surge was followed by a smaller reduction in subsequent surges. Similar trends were observed between first and second irrigations for continuous application. The Philip's infiltration model parameters (sorptivity and the parameter A), obtained from the best-fit-of-all measured infiltration data, were used to indicate effects of wetting and drying on soil structure, hence on soil physical properties. Using a Millville silt loam pre-wetting characterization, we verified that ethanol showed little or no effect on soil structure. This allowed study of differential effetcs on the saturated hydraulic conductivity for an unstable soil under wetting and drying conditions. The excepcional predictability of advance trajectories under intermittent and continnuous flow, based on infiltration information only, was demonstrated by a simple advance model. This model emphasized the dominant role of the infiltration process on the performance of surface irrigation systems. The major advantages of the model reside in modest parameter requirements and simplicity, while retaining the main features of the physical process. MenosIntermittent application of water into many soils produces changes in soil structure and hydraulic properties, resulting in faster advance with less volume of applied water as compared with continuous application. Two distinct soils, a Millville silt loam and a Red-yellow oxisol, were used to study the susceptibility of soil structure to the effects of wetting and drying. Ethanol was used to characterize the condition prior to water application and to distinguish between effects of wetting and drying (by water) on the structure of an unstable soil. The objective of this study was to quantify and show structural changes that affect soil hydraulic properties. Air entrapment effects on infiltration processes during intermittent and continuous water application were also studied. Laboratory and field experiments were carried out to achieve the objectives of this study. Important aspects of soil structural changes were identifyied by measurements with water and ethanol. The major changes were (a) reduction in porosity and (b) pore size distribution. Results reconfirmed that intermittent application of water is an efficiency way to decrease intake rates. An accentuated reduction in intake during the first surge was followed by a smaller reduction in subsequent surges. Similar trends were observed between first and second irrigations for continuous application. The Philip's infiltration model parameters (sorptivity and the parameter A), obtained from the best-fit-of-all measured in... Mostrar Tudo |
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Palavras-Chave: |
Conductivity; Condutividade; Furrwo; Hydraulic; Infiltration; Physic; Physical; Property; Regime; Sulco; Superficie; Surface. |
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Thesagro: |
Água; Engenharia Agrícola; Física; Hidráulica; Infiltração; Irrigação; Solo. |
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Thesaurus Nal: |
agricultural engineering; irrigation; soil; water. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 03336nam a2200409 a 4500
001 1789551
005 2018-07-19
008 1995 bl uuuu m 00u1 u #d
100 1 $aSILVA, H. R.
245 $aWetting-induced changes in near surface soil physical properties affecting surface irrigation.
260 $aLogan: Utah State University$c1995
300 $a188p.il.
500 $aPh.D. Dissertation.
520 $aIntermittent application of water into many soils produces changes in soil structure and hydraulic properties, resulting in faster advance with less volume of applied water as compared with continuous application. Two distinct soils, a Millville silt loam and a Red-yellow oxisol, were used to study the susceptibility of soil structure to the effects of wetting and drying. Ethanol was used to characterize the condition prior to water application and to distinguish between effects of wetting and drying (by water) on the structure of an unstable soil. The objective of this study was to quantify and show structural changes that affect soil hydraulic properties. Air entrapment effects on infiltration processes during intermittent and continuous water application were also studied. Laboratory and field experiments were carried out to achieve the objectives of this study. Important aspects of soil structural changes were identifyied by measurements with water and ethanol. The major changes were (a) reduction in porosity and (b) pore size distribution. Results reconfirmed that intermittent application of water is an efficiency way to decrease intake rates. An accentuated reduction in intake during the first surge was followed by a smaller reduction in subsequent surges. Similar trends were observed between first and second irrigations for continuous application. The Philip's infiltration model parameters (sorptivity and the parameter A), obtained from the best-fit-of-all measured infiltration data, were used to indicate effects of wetting and drying on soil structure, hence on soil physical properties. Using a Millville silt loam pre-wetting characterization, we verified that ethanol showed little or no effect on soil structure. This allowed study of differential effetcs on the saturated hydraulic conductivity for an unstable soil under wetting and drying conditions. The excepcional predictability of advance trajectories under intermittent and continnuous flow, based on infiltration information only, was demonstrated by a simple advance model. This model emphasized the dominant role of the infiltration process on the performance of surface irrigation systems. The major advantages of the model reside in modest parameter requirements and simplicity, while retaining the main features of the physical process.
650 $aagricultural engineering
650 $airrigation
650 $asoil
650 $awater
650 $aÁgua
650 $aEngenharia Agrícola
650 $aFísica
650 $aHidráulica
650 $aInfiltração
650 $aIrrigação
650 $aSolo
653 $aConductivity
653 $aCondutividade
653 $aFurrwo
653 $aHydraulic
653 $aInfiltration
653 $aPhysic
653 $aPhysical
653 $aProperty
653 $aRegime
653 $aSulco
653 $aSuperficie
653 $aSurface
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Registro original: |
Embrapa Pantanal (CPAP) |
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| Registros recuperados : 1.044 | |
| 57. |  | COSTA, N. D.; SILVA, H. R. da. Cultivares. In: SILVA, H. R. da; COSTA, N. D. (Ed.). Melão: produção aspectos técnicos. Brasília, DF: Embrapa Informação Tecnológica; Embrapa Hortaliças; Petrolina: Embrapa Semi-Árido, 2003. cap. 6, p. 29-34. (Frutas do Brasil, 33).| Tipo: Capítulo em Livro Técnico-Científico |
| Biblioteca(s): Embrapa Semiárido. |
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| 58. | | COSTA, N. D.; SILVA, H. R. da. Cultivares [Melão]. Brasília, DF: In: SILVA, H. R. da; COSTA, N. D. (Ed.). Melão produção: aspectos técnicos. Brasília, DF, Embrapa Informação Tecnológica, 2003. p. 29-34| Biblioteca(s): Embrapa Hortaliças. |
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| Registros recuperados : 1.044 | |
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