|
|
Registro Completo |
Biblioteca(s): |
Embrapa Unidades Centrais. |
Data corrente: |
16/08/2001 |
Data da última atualização: |
27/09/2004 |
Autoria: |
SILVA, P. R. F. da; RIZZARDI, M. A. R. |
Título: |
Resposta de Cultivares e Girassol a Densidade de Plantas em Duas Epocas de Semeadura. II. Caracterisitcas Associadas a Colheita. |
Ano de publicação: |
1993 |
Fonte/Imprenta: |
Pesquisa Agropecuaria Brasileira, Brasilia, v.28, n.6, p.689-700,jun.1993 |
Idioma: |
Português |
Conteúdo: |
Este experimento foi conduzido em Eldorado do Sul, Rio Grande do Sul, com o objetivo de avaliar os efeitos da densidade de plantas, em duas epocas de semeadura de tres cultivares de girassol, sobre a porcentagem de acamamento e/ou quebra de plantas e outras caracteristicas agronomicas associadas a colheita mecanizada. Visou tambem verificar a eficiencia da epoca de semeadura a densidade de plantas como praticas de manejo para antecipar a colheita do girassol. Para tanto, foram utilizadas as cultivares Contisol 711, Dekalb 180 e GR-10, semeadas em 28 de julho e 18 de setembro de 1989, na densidade de 30, 50, 70 e 90 mil plantas/ha. O aumento na densidade de plantas reduziu o diametro de caule e de capitulo. Por outro lado, a estatura de plantas aumentou com a elevação na densidade de plantas. Independentemente da densidade de plantas, a cultivar de porte alto (GR-10) apresentou maior acamamento do que as demais. A elevacao na densidade de plantas antecipou o florescimento, diminuiu a duracao do subperiodo maturacao fisiologica-colheita, bem como acelerou a perda de umidade tanto dos graos quanto do receptaculo, independentemente da cultivar e da epoca de semeadura. Este aspecto, associado a semeadura precoce (final de julho), propiciou a antecipacao na colheita. |
Palavras-Chave: |
Acamamento; caracteristicas aronomicas; estadios de desenvolvimento; umidade de graos e receptaculo. |
Categoria do assunto: |
-- |
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/AI-SEDE/20525/1/pab05_jun_93.pdf
|
Marc: |
LEADER 01909naa a2200181 a 4500 001 1105431 005 2004-09-27 008 1993 bl uuuu u00u1 u #d 100 1 $aSILVA, P. R. F. da 245 $aResposta de Cultivares e Girassol a Densidade de Plantas em Duas Epocas de Semeadura. II. Caracterisitcas Associadas a Colheita. 260 $c1993 520 $aEste experimento foi conduzido em Eldorado do Sul, Rio Grande do Sul, com o objetivo de avaliar os efeitos da densidade de plantas, em duas epocas de semeadura de tres cultivares de girassol, sobre a porcentagem de acamamento e/ou quebra de plantas e outras caracteristicas agronomicas associadas a colheita mecanizada. Visou tambem verificar a eficiencia da epoca de semeadura a densidade de plantas como praticas de manejo para antecipar a colheita do girassol. Para tanto, foram utilizadas as cultivares Contisol 711, Dekalb 180 e GR-10, semeadas em 28 de julho e 18 de setembro de 1989, na densidade de 30, 50, 70 e 90 mil plantas/ha. O aumento na densidade de plantas reduziu o diametro de caule e de capitulo. Por outro lado, a estatura de plantas aumentou com a elevação na densidade de plantas. Independentemente da densidade de plantas, a cultivar de porte alto (GR-10) apresentou maior acamamento do que as demais. A elevacao na densidade de plantas antecipou o florescimento, diminuiu a duracao do subperiodo maturacao fisiologica-colheita, bem como acelerou a perda de umidade tanto dos graos quanto do receptaculo, independentemente da cultivar e da epoca de semeadura. Este aspecto, associado a semeadura precoce (final de julho), propiciou a antecipacao na colheita. 653 $aAcamamento 653 $acaracteristicas aronomicas 653 $aestadios de desenvolvimento 653 $aumidade de graos e receptaculo 700 1 $aRIZZARDI, M. A. R. 773 $tPesquisa Agropecuaria Brasileira, Brasilia$gv.28, n.6, p.689-700,jun.1993
Download
Esconder MarcMostrar Marc Completo |
Registro original: |
Embrapa Unidades Centrais (AI-SEDE) |
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
URL |
Voltar
|
|
Registro Completo
Biblioteca(s): |
Embrapa Solos; Embrapa Solos / UEP-Recife. |
Data corrente: |
28/08/2023 |
Data da última atualização: |
06/12/2023 |
Tipo da produção científica: |
Boletim de Pesquisa e Desenvolvimento |
Autoria: |
NASCIMENTO, C. W. R. do; CEDDIA, M. B.; VASQUES, G. M.; RODRIGUES, H. M.; MARTINS, S. S.; OLIVEIRA, R. P. de; TAVARES, S. R. de L. |
Afiliação: |
CARLOS WAGNER RODRIGUES DO NASCIMENTO, UNIVERSIDADE FEDERAL RURAL DO RIO DE JANEIRO; MARCOS BACIS CEDDIA, UNIVERSIDADE FEDERAL RURAL DO RIO DE JANEIRO; GUSTAVO DE MATTOS VASQUES, CNPS; HUGO MACHADO RODRIGUES, UNIVERSIDADE FEDERAL RURAL DO RIO DE JANEIRO; SAULO SIQUEIRA MARTINS, UNIVERSIDADE FEDERAL DO PARÁ; RONALDO PEREIRA DE OLIVEIRA, CNPS; SILVIO ROBERTO DE LUCENA TAVARES, CNPS. |
Título: |
Identifying soil horizons transitions for ground-truthing and interpreting ground penetrating radar (GPR) imagery of Planosols. |
Ano de publicação: |
2023 |
Fonte/Imprenta: |
Rio de Janeiro: Embrapa Solos, 2023. |
Descrição Física: |
E-book. |
Série: |
(Embrapa Solos. Boletim de pesquisa e desenvolvimento, 285). |
ISSN: |
1678-0892 |
Idioma: |
Inglês |
Conteúdo: |
The Ground Penetrating Radar (GPR) has potential to characterize soils both vertically and horizontally. The effectiveness of using GPR relies on the interpretation of soil targets in the radargrams. For identifying the targets in their correct depths, a velocity model of the terrain is required. However, a velocity model cannot be directly obtained from GPR models using a monostatic antenna. An alternative is the generation of a depth model by measuring the velocity of the electromagnetic pulse from hyperbolas created in the radargram from the interaction of the pulse with point scatterers. On the other hand, the radargram does not always present these point scatterers for the estimation of the pulse velocity and generation of an accurate depth model. Thus, this work aimed to assess the feasibility of using iron rods as markers of the depths of soil horizons transitions in GPR images (750 MHz antenna) of Planosols, and as point scatterers to generate hyperbolas for deriving depth models for converting the Y-axis of the radargram from time to depth units. The experimental area is located in Seropédica municipality, southeastern Brazil. Three soil profiles were described and classified as Planosols, which were located at the footslope position. Iron rods (80-cm long by 8-mm in diameter) were inserted horizontally in the transitions of the soil horizons. Images (radargrams) were obtained using a GPR with a monostatic shielded antenna of 750 MHz frequency. The radargrams were pre-processed using static correction and dewow to remove noise. The pulse velocity was estimated by fitting the hyperbolas generated by the buried iron rods. As results, the 750 MHz antenna allowed visualizing the iron rods features (hyperbolas), especially in sandier horizons in the radargrams. Pulse velocity estimation was possible, which allowed the time-to-depth conversion of the Y-axis, and thus, positioning vertically the horizons transitions in the radargrams. In Planosols, the vertical and horizontal distribution of the E-to-B horizon transitions, as imaged by the GPR, is important information for irrigation planning, land zoning and soil survey. MenosThe Ground Penetrating Radar (GPR) has potential to characterize soils both vertically and horizontally. The effectiveness of using GPR relies on the interpretation of soil targets in the radargrams. For identifying the targets in their correct depths, a velocity model of the terrain is required. However, a velocity model cannot be directly obtained from GPR models using a monostatic antenna. An alternative is the generation of a depth model by measuring the velocity of the electromagnetic pulse from hyperbolas created in the radargram from the interaction of the pulse with point scatterers. On the other hand, the radargram does not always present these point scatterers for the estimation of the pulse velocity and generation of an accurate depth model. Thus, this work aimed to assess the feasibility of using iron rods as markers of the depths of soil horizons transitions in GPR images (750 MHz antenna) of Planosols, and as point scatterers to generate hyperbolas for deriving depth models for converting the Y-axis of the radargram from time to depth units. The experimental area is located in Seropédica municipality, southeastern Brazil. Three soil profiles were described and classified as Planosols, which were located at the footslope position. Iron rods (80-cm long by 8-mm in diameter) were inserted horizontally in the transitions of the soil horizons. Images (radargrams) were obtained using a GPR with a monostatic shielded antenna of 750 MHz frequency. The radargrams were p... Mostrar Tudo |
Palavras-Chave: |
Dielectric constant; Exploration geophysics; Iron rods; Poximal soil sensing; Sensoriamento proximal do solo. |
Thesagro: |
Horizonte; Solo. |
Thesaurus NAL: |
Soil horizons. |
Categoria do assunto: |
P Recursos Naturais, Ciências Ambientais e da Terra |
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/doc/1156146/1/CNPS-BPD-285-2023.epub
|
Marc: |
LEADER 03146nam a2200313 a 4500 001 2156146 005 2023-12-06 008 2023 bl uuuu u0uu1 u #d 022 $a1678-0892 100 1 $aNASCIMENTO, C. W. R. do 245 $aIdentifying soil horizons transitions for ground-truthing and interpreting ground penetrating radar (GPR) imagery of Planosols.$h[electronic resource] 260 $aRio de Janeiro: Embrapa Solos$c2023 300 $cE-book. 490 $a(Embrapa Solos. Boletim de pesquisa e desenvolvimento, 285). 520 $aThe Ground Penetrating Radar (GPR) has potential to characterize soils both vertically and horizontally. The effectiveness of using GPR relies on the interpretation of soil targets in the radargrams. For identifying the targets in their correct depths, a velocity model of the terrain is required. However, a velocity model cannot be directly obtained from GPR models using a monostatic antenna. An alternative is the generation of a depth model by measuring the velocity of the electromagnetic pulse from hyperbolas created in the radargram from the interaction of the pulse with point scatterers. On the other hand, the radargram does not always present these point scatterers for the estimation of the pulse velocity and generation of an accurate depth model. Thus, this work aimed to assess the feasibility of using iron rods as markers of the depths of soil horizons transitions in GPR images (750 MHz antenna) of Planosols, and as point scatterers to generate hyperbolas for deriving depth models for converting the Y-axis of the radargram from time to depth units. The experimental area is located in Seropédica municipality, southeastern Brazil. Three soil profiles were described and classified as Planosols, which were located at the footslope position. Iron rods (80-cm long by 8-mm in diameter) were inserted horizontally in the transitions of the soil horizons. Images (radargrams) were obtained using a GPR with a monostatic shielded antenna of 750 MHz frequency. The radargrams were pre-processed using static correction and dewow to remove noise. The pulse velocity was estimated by fitting the hyperbolas generated by the buried iron rods. As results, the 750 MHz antenna allowed visualizing the iron rods features (hyperbolas), especially in sandier horizons in the radargrams. Pulse velocity estimation was possible, which allowed the time-to-depth conversion of the Y-axis, and thus, positioning vertically the horizons transitions in the radargrams. In Planosols, the vertical and horizontal distribution of the E-to-B horizon transitions, as imaged by the GPR, is important information for irrigation planning, land zoning and soil survey. 650 $aSoil horizons 650 $aHorizonte 650 $aSolo 653 $aDielectric constant 653 $aExploration geophysics 653 $aIron rods 653 $aPoximal soil sensing 653 $aSensoriamento proximal do solo 700 1 $aCEDDIA, M. B. 700 1 $aVASQUES, G. M. 700 1 $aRODRIGUES, H. M. 700 1 $aMARTINS, S. S. 700 1 $aOLIVEIRA, R. P. de 700 1 $aTAVARES, S. R. de L.
Download
Esconder MarcMostrar Marc Completo |
Registro original: |
Embrapa Solos (CNPS) |
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
Fechar
|
Expressão de busca inválida. Verifique!!! |
|
|