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Registros recuperados: 2.661 | |
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Yemadje,Pierrot Lionel; Guibert,Hervé; Blavet,Didier; Olina,Jean-Paul; Chevallier,Tiphaine; Deleporte,Philippe; Bernoux,Martial. |
Soil respiration is a major component of the global carbon cycle which links ecosystems and the atmosphere. To evaluate the reaction of soil respiration after wetting, during a dry period, soil respiration and associated environmental factors were measured over a 24-h period, during the dry season in North Cameroon after wetting the soil. Over 24-h, soil respiration rates followed a quadratic curve during the day coming close to linear at night, while soil temperature and moisture together explained at least 73 % of the variations during the 24-h observed. These soil respiration rates increased during the morning, peaked between 11h00 and 13h00 and then decreased gradually to the minimum around 06h00. These observations were used to propose a method for... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diel soil respiration; Soil temperature; Soil moisture. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000500452 |
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Nielsen,D.R.; Hopmans,J.W.; Kutílek,M.; Wendroth,O.. |
We initially review basic concepts of the forces acting on soil water, soil water potential and soil water retention, and equations to describe soil water movement under water-saturated and unsaturated conditions. Processes of infiltration, evaporation and redistribution of water will be presented for simple initial and boundary conditions occurring within homogeneous soil columns. Next we consider the physical, chemical and biological processes within a soil profile that distribute, dilute or concentrate solute species within the liquid phase of a soil The relative concentration of solutes in the liquid phase governs not only the retention and transport of water within soils but also contributes to our understanding of managing the quality of water within... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Solute transport; Regionalized variable. |
Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161997000300012 |
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Belavenutti,Pedro; Romero,Carlos; Diaz-Balteiro,Luis. |
ABSTRACT: The application of optimization methods to forest management has given rise to a successful line of investigation in recent decades. However, there have been few publications associated with the application of these techniques to the management of industrial forest plantations (those with short or medium rotations, always less than 50 years), which consider the important role played by these forest systems in the supply of diverse goods and services. This study presents an overview of this literature which, by analyzing 67 articles published in journals contained in the ISI Web of Science, highlight, among other aspects, the techniques employed, their evolution, their planning type (strategic, tactical or operational), the functional objectives... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mathematical programming; Forest management; Industrial plantations; Timber harvest scheduling. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162018000300239 |
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Leite,João Guilherme Dal Belo; Silva,João Vasco; Justino,Flávio Barbosa; Ittersum,Martin K. van. |
Pushed by the Brazilian biodiesel policy, sunflower (Helianthus annuus L.) production is becoming increasingly regarded as an option to boost farmers' income, particularly under semi-arid conditions. Biodiesel related opportunities increase the demand for decision-making information at different levels, which could be met by simulation models. This study aimed to evaluate the performance of the crop model OILCROP-SUN to simulate sunflower development and growth under Brazilian conditions and to explore sunflower water- and nitrogen-limited, water-limited and potential yield and yield variability over an array of sowing dates in the northern region of the state of Minas Gerais, Brazil. For model calibration, an experiment was conducted in which two... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Production systems; Family farms; Biodiesel crops; Climate classification. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162014000500001 |
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Maia,Ana Paula de Assis; Oliveira,Stanley Robson de Medeiros; Moura,Daniella Jorge de; Sarubbi,Juliana; Vercellino,Rimena do Amaral; Medeiros,Brenda Batista Lemos; Griska,Paulo Roberto. |
Thermal comfort is of great importance in preserving body temperature homeostasis during thermal stress conditions. Although the thermal comfort of horses has been widely studied, there is no report of its relationship with surface temperature (T S). This study aimed to assess the potential of data mining techniques as a tool to associate surface temperature with thermal comfort of horses. T S was obtained using infrared thermography image processing. Physiological and environmental variables were used to define the predicted class, which classified thermal comfort as "comfort" and "discomfort". The variables of armpit, croup, breast and groin T S of horses and the predicted classes were then subjected to a machine learning process. All variables in the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Feature selection methods; Data mining; Surface temperature; Infrared thermography; Thermoregulation. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162013000600001 |
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Pinto,Leandro Campos; Mello,Carlos Rogério de; Norton,Lloyd Darrell; Poggere,Giovana Clarice; Owens,Phillip Ray; Curi,Nilton. |
ABSTRACT: The Mantiqueira Range region is one of the most important headwaters in southeastern Brazil. In this context, the relationship between pedology and hydrology has been debated and analyzed in recent years, contributing to the creation of a multidisciplinary science call hydropedology. Therefore, the aim of this study was to evaluate the hydropedological properties of a mountainous Clayey Humic Dystrudept in the Mantiqueira Range region, in the state of Minas Gerais, Brazil, comparing two land-uses, native forest and pasture. The hydraulic conductivity results demonstrated that native forest (MFO) has a strong influence on this parameter, offering conditions for movement of water in the soil that are more adequate in this profile than in pasture.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: S index; Saturated hydraulic conductivity; Soil pore size distribution; Soil erosion; Water quality. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162018000100060 |
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Gomes,Regina Lucia Ferreira; Costa,Marcones Ferreira; Alves-Pereira,Alessandro; Bajay,Miklos Maximiliano; Viana,João Paulo Gomes; Valente,Sérgio Emílio dos Santos; Lopes,Ângela Celis de Almeida; Zucchi,Maria Imaculada; Pinheiro,José Baldin. |
ABSTRACT Some germplasm collections have a high number of accessions, which makes it difficult to explore the genetic variability present in the germplasm bank due to the redundancy and the difficulty of detailed analysis of all conserved accessions. Therefore, our study aimed to analyze the genetic diversity of 153 lima bean (Phaseolus lunatus) accessions for the purpose of constructing a core collection. Eleven SSRs were used for this purpose. The 153 lima bean accessions can be represented by low redundancy using a minimum of 34 accessions, thus representing 22 % of the size of the entire germplasm bank. The core collection had a higher Shannon diversity index and expected heterozygosity (1.906 and 0.811, respectively) than those presented by the entire... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Germplasm; Genetic diversity; Genetic structure; Microsatellite markers. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162020000201100 |
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Tullio,A. A.. |
Esta pesquisa procurou identificar a prática pedagógica do professor de Engenharia Agronômica, quais as concepções do processo de aprendizagem e em que medida o conceito teórico do professor é coerente com a sua prática. A prática pedagógica foi aqui delimitada como sendo o cotidiano do professor na execução de seu ensino. O público alvo foram os docentes e discentes do Curso de Engenharia Agronômica da Escola Superior de Agricultura "Luiz de Queiroz"- Campus de Piracicaba da USP. O método expositivo foi predominante, apoiado no uso do quadro negro e retroprojetor. O professor nesse método é a figura central do processo ensino-aprendizagem. A freqüência bastante acentuada em Congressos tem trazido uma atualização constante em termos de conteúdo. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Agronomia; Ensino; Pedagogia. |
Ano: 1995 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161995000300029 |
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Calbo,Adonai Gimenez. |
The availability of a rapid method to evaluate the soil water content (U) can be an important tool to determine the moment to irrigate. The soil areometer consists of an elongated hydrostatic balance with a weighing pan, a graduated neck, a float and a pynometric flask. In this work an areometer was adapted to rapidly measure soil water content without the need of drying the soil. The expression U = (M A - M AD)/(M M -M A) was used to calculate the soil water content. In this equation M M is the mass to level the areometer with the pycnometric flask filled with water, M A the mass to level the areometer with a mass M M of soil in the pycnometer, the volume being completed with water, and similarly M AD the mass added to the pan to level the areometer with... |
Tipo: Info:eu-repo/semantics/report |
Palavras-chave: Hydrostatic balance; Irrigation moment; Pycnometer; Soil humidity. |
Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162002000400029 |
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Kim,Jaeyoung; Kim,Ki-Seung; Kim,Yoonha; Chung,Yong Suk. |
ABSTRACT Drought is a major threat worldwide for crop production, especially due to the rapid climate changes. Current drought solutions involve improving irrigation system, rainwater harvesting, damming, cloud seeding, and changes of cultivation methods. Despite effective, each solution has economic, environmental, and temporal drawbacks. Among all solutions, the most effective, inexpensive and manageable method is the use of drought-tolerant cultivars via plant breeding. However, conventional plant breeding is a time-consuming and laborious task, especially for phenotypic data acquisition of target traits of numerous progenies. High-throughput phenotyping (HTP) is a recently developed method and has potential to overcome the mentioned issues. HTP offers... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sensors; Remote sensing platforms; Image analysis; Drought solution; Plant breeding. |
Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162021000401801 |
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Qian,Jianping; Xing,Bin; Wu,Xiaoming; Chen,Meixiang; Wang,Yan'an. |
ABSTRACT: Apple yield estimation using a smartphone with image processing technology offers advantages such as low cost, quick access and simple operation. This article proposes distribution framework consisting of the acquisition of fruit tree images, yield prediction in smarphone client, data processing and model calculation in server client for estimating the potential fruit yield. An image processing method was designed including the core steps of image segmentation with R/B value combined with V value and circle-fitting using curvature analysis. This method enabled four parameters to be obtained, namely, total identified pixel area (TP), fitting circle amount (FC), average radius of the fitting circle (RC) and small polygon pixel area (SP). A... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Potential yield prediction model; Image processing; Mobile phone application development; Orchard precision management. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162018000400273 |
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Registros recuperados: 2.661 | |
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