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| Registros recuperados: 11 | |
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| Steinmetz,Alice Alonzo; Cassalho,Felício; Caldeira,Tamara Leitzke; Oliveira,Vinícius Augusto de; Beskow,Samuel; Timm,Luis Carlos. |
| ABSTRACT Soil erosion is currently one of the main concerns in agriculture, water resources, soil management and natural hazards studies, mainly due to its economic, environmental and human impacts. This concern is accentuated in developing countries where the hydrological monitoring and proper soil surveys are scarce. Therefore, the use of indirect estimates of soil loss by means of empirical equations stands out. In this context, the present study proposed the assessment of the Revised Universal Soil Loss Equation (RUSLE) with the aid of Geographical Information Systems (GIS) and remote sensing for two agricultural watersheds in southern Rio Grande do Sul - Brazil. Among all RUSLE factors, LS showed the closest patterns to the local when compared to the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil erosion; Revised universal soil loss equation; Geographical information systems; Remote sensing. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542018000600575 |
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| Islabão,Gláucia Oliveira; Lima,Cláudia Liane Rodrigues de; Vahl,Ledemar Carlos; Timm,Luis Carlos; Teixeira,Juliana Brito da Silva. |
| ABSTRACT The combustion of rice husk generates a partially burnt mixture called rice husk ash (RHA) that can be used as a source of nutrients to crops and as a conditioner of soil physical properties. The objective of this study was to evaluate the effect of RHA levels on the hydro-physical properties of a Typic Hapludult. The experimental design was composed of random blocks with four replications, which comprised plots of 24 m2 and treatments with increasing RHA rates: 0, 40, 80 and 120 Mg ha-1. Undisturbed soil samples were collected in the soil layers of 0.00-0.10 and 0.10-0.20 m after nine months of RHA application, using steel cylinders (0.03 m of height and 0.047 m of diameter). These samples were used to determine soil bulk density (Bd), total soil... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bulk density; Soil porosity; Available water capacity; Soil compressibility; Soil aggregation. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832016000100407 |
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| Timm,Luis Carlos; Fante Jr.,Lorival; Barbosa,Emanuel Pimentel; Reichardt,Klaus; Bacchi,Osny Oliveira Santos. |
| Para estudar a interação solo-planta utilizou-se um modelo de espaço de estados (regressão dinâmica) comparativamente à um modelo de regressão estática, em versão convencional e em versão sequencial. Para tal, foram utilizados dados experimentais de densidade do solo, macroporosidade, microporosidade e porosidade total de um solo Latossolo Vermelho Escuro, além da densidade radicular por comprimento de raiz por unidade de volume, de uma cultura de aveia forrageira. Das variáveis explanatórias estudadas, a porosidade total apresentou correlação bastante significativa com a densidade radicular, considerada como a variável resposta do estudo. Um modelo de regressão estática representado na forma de espaço de estados com estimação seqüencial forneceu um... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Variabilidade espacial; Regressão dinâmica; Regressão estática; Estimação seqüencial. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162000000400025 |
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| Miola,Ezequiel Cesar Carvalho; Pauletto,Eloy Antonio; Lima,Cláudia Liane Rodrigues de; Pinto,Luiz Fernando Spinelli; Timm,Luis Carlos. |
| Na quantificação do intervalo hídrico ótimo (IHO), são utilizados diferentes limites críticos de resistência à penetração (RP) e umidade na capacidade de campo (θCC). Para solos agrícolas, esses valores estão sendo documentados na literatura. Entretanto, para solos construídos após mineração de carvão, constata-se grande lacuna de informações. O objetivo deste trabalho foi quantificar a faixa de variação do intervalo hídrico ótimo de um solo construído sob diferentes plantas de cobertura na área de mineração de carvão de Candiota, sul do Brasil, considerando diferentes limites críticos de umidade do solo na capacidade de campo e de resistência à penetração. Foram avaliadas no experimento, em blocos casualizados com quatro repetições, as seguintes plantas... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Densidade crítica; Plantas de cobertura; Qualidade do solo; Solos construídos. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832015000200563 |
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| Terra,Viviane Santos Silva; Valgas,Ricardo Alexandre; Reisser Júnior,Carlos; Timm,Luis Carlos; Pereira,José Francisco Martins; Carvalho,Flávio Luiz Carpena; Oldoni,Henrique. |
| In the State of Rio Grande do Sul, the municipality of Pelotas is responsible for 90 % of peach production due to its suitable climate and soil conditions. However, there is the need for new studies that aim at improved fruit quality and increased yield. The aim of this study was to evaluate the relationship that exists between soil physical properties and properties in the peach plant in the years 2010 and 2011 by the technique of multivariate canonical correlation. The experiment was conducted in a peach orchard located in the municipality of Morro Redondo, RS, Brazil, where an experimental grid of 101 plants was established. In a trench dug beside each one of the 101 plants, soil samples were collected to determine silt, clay, and sand contents, soil... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Prunus persica; Canonical correlation; Soil physical properties. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000300007 |
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| Oliveira,Júlio César Martins de; Reichardt,Klaus; Bacchi,Osny O.S.; Timm,Luis Carlos; Dourado-Neto,Durval; Trivelin,Paulo César Ocheuse; Tominaga,Tânia Toyomi; Navarro,Roberta de Castro; Piccolo,Marisa de Cássia; Cássaro,Fábio Augusto Meira. |
| Results of an organic matter management experiment of a sugar cane crop are reported for the first cropping year. Sugar cane was planted in October 1997, and labeled with a 15N fertilizer pulse to study the fate of organic matter in the soil-plant system. A nitrogen balance is presented, partitioning the system in plant components (stalk, tip and straw), soil components (five soil organic matter fractions) and evaluating leaching losses. The 15N label permitted to determine, at the end of the growing season, amounts of nitrogen derived from the fertilizer, present in the above mentioned compartments. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fertilizer; Nitrogen; N label; Soil; Sugar cane. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162000000300015 |
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| Oliveira,Marcio Paulo de; Tavares,Maria Hermínia Ferreira; Uribe-Opazo,Miguel Angel; Timm,Luis Carlos. |
| Statistical models allow the representation of data sets and the estimation and/or prediction of the behavior of a given variable through its interaction with the other variables involved in a phenomenon. Among other different statistical models, are the autoregressive state-space models (ARSS) and the linear regression models (LR), which allow the quantification of the relationships among soil-plant-atmosphere system variables. To compare the quality of the ARSS and LR models for the modeling of the relationships between soybean yield and soil physical properties, Akaike's Information Criterion, which provides a coefficient for the selection of the best model, was used in this study. The data sets were sampled in a Rhodic Acrudox soil, along a spatial... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Autocorrelation; Cross correlation; Linear regression; State-space model; Soil and plant properties. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000100009 |
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| Silva,Adriana Lúcia da; Roveratti,Renato; Reichardt,Klaus; Bacchi,Osny Oliveira Santos; Timm,Luis Carlos; Bruno,Isabeli Pereira; Oliveira,Julio César Martins; Dourado Neto,Durval. |
| Establishing field water balances is difficult and costly, the variability of their components being the major problem to obtain reliable results. This component variability is presented herein for a coffee crop grown in the Southern Hemisphere, on a tropical soil with 10% slope. It was observed that: rainfall has to be measured with an appropriate number of replicates; irrigation can introduce great variability into calculations; evapotranspiration, calculated as a remainder of the water balance equation, has exceedingly high coefficients of variation; the soil water storage component is the major contributor in error propagation calculations to estimate evapotranspiration; and that runoff can be satisfactorily controlled on the 10% slope through crop... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Component variability; Rainfall; Evapotranspiration; Soil water storage. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000200001 |
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| Registros recuperados: 11 | |
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