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Registros recuperados: 31 | |
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Laurani,Raffael A.; Ralisch,Ricardo; Tavares Filho,João; Soares,Décio S.; Ribon,Adriana A.. |
O estudo da distribuição de poros é importante na avaliação física do solo submetido a diferentes sistemas de produção. O objetivo deste trabalho foi avaliar a distribuição de poros de um Latossolo Vermelho Eutroférrico, como um parâmetro de sua qualidade física para analisar sua eficiência na implantação do sistema de plantio direto. Empregou-se um delineamento experimental inteiramente casualizado, com quatro tratamentos, na rotação de inverno (milho safrinha, coquetel de adubos verdes, aveia-preta e trigo) e duas profundidades (0-0,2 m e 0,2-0,4 m), com três repetições por tratamento. Após três anos de implantação dos tratamentos (coberturas vegetais), foram realizadas determinações físicas (densidade do solo), fisico-hídricas do solo (macroporosidade,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Porosidade; Curva de retenção; Manejo do solo. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162004000200013 |
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Fernandes,Kathleen Lourenço; Ribon,Adriana Aparecida; Marques Junior,José; Bahia,Angélica Santos Rabelo de Souza; Tavares Filho,João. |
Abstract: The objective of this work was to estimate the iron oxide contents (hematite and goethite) and to characterize the color and the spectral and magnetic signatures of Cerrado soils in the state of Goiás, Brazil. Six Oxisols and one Inceptisol were studied. Spectral and magnetic signatures were determined by diffuse reflectance spectroscopy (DRS) and magnetic susceptibility, respectively. Then, the spectral curves and the second derivative calculations were used to determine hematite and goethite contents, as well as soil color after conversion into tristimulus values. Hematite and goethite contents were also obtained by x-ray diffractometry, and soil color was also defined in the field (Munsell color chart). The values for the isomorphic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diffuse reflectance spectroscopy; Goethite; Hematite; Magnetic susceptibility; Oxisols. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2017001000923 |
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Rós,Amarílis Beraldo; Araújo,Humberto Sampaio de; Narita,Nobuyoshi; Tavares Filho,João. |
O objetivo deste trabalho foi avaliar a produção de mudas de batata-doce em bandejas de poliestireno, com utilização de fertilizante de liberação lenta, e estabelecer o tempo adequado de permanência dessas mudas nas bandejas. Utilizou-se o delineamento experimental inteiramente casualizado, em arranjo fatorial 5x5, com cinco doses do fertilizante de liberação lenta osmocote NPK 15-09-12 (0, 50, 100, 150 e 200 g por 25 kg de substrato) e cinco tempos de permanência nas bandejas (14, 28, 42, 56 e 70 dias após o plantio, DAP). Foram avaliados o número de raízes e de folhas e suas respectivas massas de matéria seca. Além disso, avaliou-se a integridade dos torrões em função do tempo de permanência das mudas nas bandejas, em experimento sem adição de... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ipomoea batatas; Enraizamento; Estaca herbácea; Miniestaca; Multiplicação; Substrato. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2011000800009 |
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Tavares Filho,João; Feltran,Clarissa Tieme Matsuda; Oliveira,José Francirlei de; Almeida,Edinei de; Guimarães,Maria de Fátima. |
O objetivo deste trabalho foi identificar atributos de solo importantes para a estimativa do índice de estabilidade de agregados. Para a identificação dos atributos, utilizou-se a regressão múltipla "stepwise" em dados coletados de Latossolo Vermelho eutroférrico, cultivado em sistema de plantio direto. Para a obtenção dos modelos de estimativa do índice de estabilidade de agregados (IeaE), foram analisadas dez variáveis independentes: argila total, densidade do solo, resistência à penetração, matéria orgânica, pH em água, capacidade efetiva de troca de cátions, água disponível, volume total de poros, macroporosidade e umidade gravimétrica. Os atributos argila total (Arg), densidade do solo (Ds), resistência à penetração (RP), matéria orgânica (MO) e pH... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Agregação; Estrutura do solo; Função de pedotransferência; Modelagem; Plantio direto; Regressão múltipla. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012000300016 |
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Tavares Filho,João; Guimarães,Maria de Fátima; Curmi,Pierre; Tessier,Daniel. |
It is known that any kind of soil management causes changes in the soil physical characteristics and can affect agricultural yield. The purpose of this study was to evaluate soil properties of an Alfisol and soybean yield under different management systems for no-tillage annual crops, no-tillage with chiseling and no-tillage crop rotation. The 11-year experiment was initiated in the 1998/99 growing season, on 100 x 30 m plots (11 % slope). Soil samples (5 per management system) were systematically collected (0-25 cm layer) in the summer growing season, to quantify soil organic matter, bulk density, macroporosity and flocculation, as well as soybean yield. The highest values for soil bulk density and organic matter content and the lowest for macroporosity... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: No tillage; Soil physical properties; Organic matter; Crop rotation. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000100026 |
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Machado,Walquíria; Telles,Tiago Santos; Tavares Filho,João; Guimarães,Maria de Fátima; Alves,Grace Bungenstab; Borges,José Luiz Bernardo. |
This study had the purpose of evaluating the effects of two management types of sugarcane: harvesting of burnt cane (BCH) and mechanized harvesting of unburnt green cane (MCH), on some soil physical properties of a dystrophic Rhodic Haplustox. The data were then compared with results for the same soil type under native forest. A completely randomized design was used, with three treatments and 20 replications. The following characteristics were determined: organic matter, aggregate stability, soil bulk density, and porosity at depths of 0-0.20 m and soil penetration resistance. After 15 years of cultivation, there were some alterations in the soil under cane burnt before harvesting, evidenced by a drop in the weighted average diameter of stable aggregates... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Saccharum officinarum; Soil bulk density; Porosity; Soil penetration resistance; Soil aggregate stability. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832010000600004 |
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Rós,Amarílis Beraldo; Tavares Filho,João; Barbosa,Graziela Moraes de Cesare. |
Trabalhos sobre preparo reduzido em solos cultivados com raízes e tubérculos são escassos e controversos. Assim, este trabalho teve por objetivo avaliar o impacto de sistemas de preparo em propriedades físicas de um Argissolo Vermelho-Amarelo e no crescimento de raízes tuberosas de batata-doce. Para avaliação das propriedades físicas do solo, foi instalado experimento em blocos ao acaso, esquema de parcelas subdivididas. As parcelas corresponderam aos tratamentos: preparo convencional, com confecção de leiras, e preparo reduzido, com manutenção de palhada superficial e as subparcelas, às épocas de coleta: 120 e 180 dias após o plantio (DAP) da cultura de batata-doce. Foram avaliados os atributos físicos densidade do solo, porosidade total, macro e... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ipomoea batatas; Plantio direto; Densidade do solo; Resistência do solo à penetração; Porosidade do solo; Formato de raiz. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832013000100025 |
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Watanabe,Rafaela; Tormena,Cássio Antonio; Guimarães,Maria de Fátima; Tavares Filho,João; Ralisch,Ricardo; Franchini,Julio; Debiasi,Henrique. |
ABSTRACT Soil and crop management systems change the soil structure, thereby affecting soil quality. The “profil cultural” method (PCM) has been used to identify the effects of management systems on soil structure; however, few studies relate the structures identified by the PCM to quantitative indicators of soil structural quality. This study aimed to quantify soil structures using the PCM and relate these structures to bulk density (Bd), critical bulk density (Bdc), soil aeration capacity (εa), least limiting water range (LLWR), and soil air permeability (Ka) under different soil and crop management systems. The study was developed in a long-term experiment (24 years) involving two systems of soil management (no-tillage and conventional tillage) and two... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Least limiting water range; Air permeability; No-tillage; Conventional tillage. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100510 |
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Silva,Francisco Carlos Mainardes da; Sachs,Luís Guilherme; and,Inês Cristina Batista Fonseca; Tavares Filho,João. |
ABSTRACT Perennial forage crops used in crop-livestock integration (CLI) are able to accumulate large amounts of straw on the soil surface in no-tillage system (NTS). In addition, they can potentially produce large amounts of soluble organic compounds that help improving the efficiency of liming in the subsurface, which favors root growth, thus reducing the risks of loss in yield during dry spells and the harmful effects of “overliming”. The aim of this study was to test the effects of liming on two models of agricultural production, with and without crop-livestock integration, for 2 years. Thus, an experiment was conducted in a Latossolo Vermelho (Oxisol) with a very clayey texture located in an agricultural area under the NTS in Bandeirantes, PR, Brazil.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Brachiaria ruziziensis; No-tillage system; Ion mobility. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832015000501463 |
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Domingos,Mausy Marchel Marques; Gasparetto,Nelson Vicente Lovatto; Nakashima,Paulo; Ralisch,Ricardo; Tavares Filho,João. |
Alterações estruturais causadas no solo pelos sistemas de manejo podem resultar em compactação e interferir no desenvolvimento radicular das culturas. Com o objetivo de avaliar os influxos do tipo de manejo sobre a estrutura do solo, por meio de métodos qualitativo (perfil cultural) e quantitativo (densidade), realizou-se um estudo em solo derivado do basalto, com textura argilosa a muito argilosa, no município de Maringá (PR), Terceiro Planalto Paranaense, coordenadas 23 º 29 ' S e 51 º 59 ' W, submetido aos sistemas de manejo convencional com sucessão de milho (Zea mays L. ) e soja (Glycine max); e plantio direto com rotação de trigo (Triticum spp.), milho (Zea mays L.), feijão (Phaseolus vulgaris), aveia-preta (Avena strigosa) e soja durante 20 anos.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Manejo do solo; Física do solo; Perfil cultural. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000600001 |
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Tavares Filho,João; Melo,Thadeu Rodrigues de; Machado,Wesley; Maciel,Bruno Vieira. |
Soils are the foundation of terrestrial ecosystems and their role in food production is fundamental, although physical degradation has been observed in recent years, caused by different cultural practices that modify structures and consequently the functioning of soils. The objective of this study was to evaluate possible structural changes and degradation in an Oxisol under different managements for 20 years: no-tillage cultivation with and without crop rotation, perennial crop and conventional tillage, plus a forested area (reference). Initially, the crop profile was described and subsequently, 10 samples per management system and forest soil were collected to quantify soil organic matter, flocculation degree, bulk density, and macroporosity. The results... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Profile; Soil physical properties; Organic matter; Soil quality. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000400025 |
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Macedo,Sônia de Fátima Schilickmann; Grimaldi,Michel; Medina,Cristiane Conti; Cunha,José Edézio da; Guimarães,Maria de Fátima; Tavares Filho,João. |
ABSTRACT Soil structure plays an important role in water retention, infiltration capacity, porosity, and penetration resistance. The aim of this study was to evaluate the unsaturated hydraulic conductivity and physical properties of Oxisol soils (bulk density and macro-, micro-, and total porosity) in the structures identified using the profil cultural method in areas under two different management practices (perennial pasture and sugarcane). Three pits were dug in each plot to find out how homogeneous morphological structural units (HMSU) were organized in the soil. Next, unsaturated hydraulic conductivity (Ki) was measured in situ inside each HMSU using a triple-ring infiltrometer at multiple suction. Six samples were collected (two samples for each kind... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil use; Compaction; Soil bulk density; Soil porosity. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832017000100524 |
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Tavares Filho,João; Feltran,Clarissa Tieme Matsuda; Oliveira,José Francirlei de; Almeida,Edinei de. |
Soil penetration resistance is an important property that affects root growth and elongation and water movement in the soil. Since no-till systems tend to increase organic matter in the soil, the purpose of this study was to evaluate the efficiency with which soil penetration resistance is estimated using a proposed model based on moisture content, density and organic matter content in an Oxisol containing 665, 221 and 114 g kg-1 of clay, silt and sand respectively under annual no-till cropping, located in Londrina, Paraná State, Brazil. Penetration resistance was evaluated at random locations continually from May 2008 to February 2011, using an impact penetrometer to obtain a total of 960 replications. For the measurements, soil was sampled at depths of 0... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: No-till; Compaction; Physical properties; Organic matter. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000100010 |
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Portella,Cibele Mascioli Rebello; Guimarães,Maria de Fátima; Feller,Christian; Fonseca,Inês Cristina de Batista; Tavares Filho,João. |
Considering that the soil aggregation reflects the interaction of chemical, physical and biological soil factors, the aim of this study was evaluate alterations in aggregation, in an Oxisol under no-tillage (NT) and conventional tillage (CT), since over 20 years, using as reference a native forest soil in natural state. After analysis of the soil profile (cultural profile) in areas under forest management, samples were collected from the layers 0-5, 5-10, 10-20 and 20-40 cm, with six repetitions. These samples were analyzed for the aggregate stability index (ASI), mean weighted diameter (MWD), mean geometric diameter (MGD) in the classes > 8, 8-4, 4-2, 2-1, 1-0.5, 0.5-0.25, and < 0.25 mm, and for physical properties (soil texture, water... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aggregation indices; Aggregate size classes; Total organic carbon. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000600021 |
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Registros recuperados: 31 | |
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