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Assessment of energetic requirements of reared molluscs and of their main competitors ArchiMer
Deslous-paoli, Jean-marc.
In the context of aquaculture in open sea• the amount: and qua11ty of food is variable according to the season and the physical flux in the ecosystem (carrying capacity ecosystems ). Thus to predict the potential al production of a cultivated ecosystem, it is mandatory 'co know ~he seasona1 changes in organisms energy balance of cultivated organisms. These changes result from the environmental variability either in the temperature or more significantly in the nutrients supply (Bayne and Newell, 1983). The techniques of physiological energetics allow to understand the adaptations of the energy balance in bivalve molluscs and to calculate the complete energy budget all over the seasonal variations of the field. Such studies are few, they include...
Tipo: Text Palavras-chave: Crepidula fornicata; Perna perna; Mytilus chilensis; Mytilus edulis; Mercenaria mercenaria; Crassostrea gigas; Scrobicularia plana; Physilogy; Energy balance; Carrying capacity ecosystems.
Ano: 1985 URL: http://archimer.ifremer.fr/doc/1985/acte-2960.pdf
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BALANÇO ECONÔMICO DA PRODUÇÃO DE MAMONA E BALANÇO ENERGÉTICO DA OBTENÇÃO DE BIODIESEL NO ESTADO DO CEARÁ AgEcon
Braga, Francisco Laercio Pereira; Khan, Ahmad Saeed; Mera, Ruben Dario Mayorga.
Dada a necessidade de se conhecer melhor a viabilidade econômica e energética da mamona (Ricinus communis) para o Estado do Ceará, enquanto um dos maiores produtores de oleaginosas no Nordeste do Brasil, o presente trabalho foi desenvolvido com o objetivo de elaborar um balanço econômico e energético da produção de mamona para obtenção de biodiesel no Estado do Ceará. A pesquisa foi realizada nos Municípios de Boa Viagem, Tauá e Pedra Branca. Foram utilizados os dados primários recolhidos dos produtores em entrevistas diretas. Na análise da rentabilidade foram consideradas as receitas e os custos de produção por hectare nos municípios selecionados. Os principais resultados obtidos na pesquisa indicam que a produção de mamona cearense nos três municípios...
Tipo: Conference Paper or Presentation Palavras-chave: Mamona; Biodiesel; Balanço energético; Balanço econômico; Castor seed; Biodiesel; Economic feasibility; Energy balance; Crop Production/Industries.
Ano: 2008 URL: http://purl.umn.edu/109722
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Características climáticas del océano Atlántico sudoccidental OceanDocs
Hoffmann, J.; Núñez, M.; Piccolo, M.C..
The climate of the SW Atlantic Ocean is described for representative summer and winter months. The description is based on mean fields of surface and upperair metereological measurements. Maps and data have been obtained from national and international information centers. Other sources also were considered. The Malvinas Current is a year-round sink for the sensitive heatflux. The Malvinas and Brazil Currents and their zone of confluence are the most important oceanographic and climate features in the region of South Atlantic Ocean.
Tipo: Book Section Palavras-chave: Climatology; Air temperature; Surface temperature; Winds; Atmospheric circulation; Energy balance; Climatology; Winds; Atmospheric circulation; Air temperature; Energy balance; Http://aims.fao.org/aos/agrovoc/c_1671; Http://aims.fao.org/aos/agrovoc/c_8401; Http://aims.fao.org/aos/agrovoc/c_29546; Http://aims.fao.org/aos/agrovoc/c_230; Http://aims.fao.org/aos/agrovoc/c_2566.
Ano: 1997 URL: http://hdl.handle.net/1834/1723
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Desarrollo de un modelo de "Footprint" de los flujos de calor sensible y radiación neta en la vegetación. Colegio de Postgraduados
Marín Sosa, Ma. Isabel.
Los intercambios de energía y masa entre la superficie de la tierra y la atmósfera controlan la disposición de agua en el planeta, por lo que su conocimiento y modelación es importante. A escalas regionales, como los distritos de riego, el tema se ha abordado usando sensores remotos en satélites, donde el escalamiento de las mediciones de campo a las áreas de influencia o footprints de las observaciones satelitales deben ser intercomparables. A nivel de campo, se ha empleado la técnica de covarianza de vórtices para medir de forma directa los flujos de energía y masa, no obstante, se han encontrado problemas en el cierre de los balances, que se argumenta son producto del uso de diferentes footprints de las componentes del balance de energía. Así, en el...
Palavras-chave: Cierre balance de energía; Modelo uni-paramétrico de la geometría sol-sensor; Temperatura aerodinámica; Eddy Covariance; Temperatura radiativa; Albedo; Balance de energía; Función de distribución bidireccional de la reflectancia; Función de distribución bidireccional de la emisividad; Energy balance closure; Sun-sensor uni-parametric model; Aerodynamic temperature; Eddy covariance technique; Radiative temperature; Energy balance; Bidireccional reflectance distribution function; Bidireccional emissivity distribution function; Hidrociencias; Doctorado.
Ano: 2013 URL: http://hdl.handle.net/10521/2035
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Effect of Site Specific Weather Conditions on the Energy Consumption of a High Temperature Continuous Flow Corn Dryer CIGR Journal
de la Torre, Diego Antonio.
The estimation of drying energy consumption is important for grain elevators and the grain processing industry in order to compute the drying cost and also for properly planning the energy supply during the drying season. It is also important for making energy policies related to agriculture. Locations with different weather should have different drying performances but this effect was not sufficiently studied in previous research. The main goal of this study was to determine the energy requirement for drying yellow dent corn with a continuous flow high temperature dryer for ten locations in Argentina with different weather conditions. The study was carried out using historical weather data of ten locations scattered through the corn producing region of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Grain postharvest; Grain drying grain drying; Simulation; Energy balance; Energy losses; Ambient temperature.
Ano: 2014 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2962
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Effect of unsaturated fatty acid supplementation on digestion, metabolism and nutrient balance in dairy cows during the transition period and early lactation R. Bras. Zootec.
Rennó,Francisco Palma; Freitas Júnior,José Esler de; Gandra,Jefferson Rodrigues; Maturana Filho,Milton; Verdurico,Lenita Camargo; Rennó,Luciana Navajás; Barletta,Rafael Villela; Vilela,Flávio Garcia.
The objective of this study was to evaluate the influence of unsaturated fatty acids in diets for dairy cows during the transition period and early lactation on intake, digestion and nutrient balance. Thirty-six multiparous and pregnant Holstein cows were randomly distributed to receive one of the experimental diets in the period from 35 days before the expected date of parturition to 84 days post-partum. Diets were fed as a total mixed ration and were as follows: control (C); soybean oil (SO), based on inclusion of 30 g/kg (DM basis); and calcium salts of unsaturated fatty acids (CS), based on inclusion of 30 g/kg (DM basis). Pre-partum dry matter intakes (DMI) of cows fed C, SO and CS were 11.9, 9.5 and 9.6 kg/d, respectively. Post-partum DMI was...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Dry matter intake; Energy balance; Ruminant digestion.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982014000400212
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Elevage de copepodes harpacticoïdes (Tisbe holothuriae) en cycle complet. Rôle des facteurs température et nutrition ArchiMer
Gaudy, R.; Guerin, J.p..
Following are results obtained in our laboratory during breeding expe­riments with an harpacticoid copepod, Tisbe holothuriae. In small size volumes (200 ml), the potential production appears to be higher when an artificial compound food of animal substances is used instead of a vegetal diet. In medium volume experiments (100 l) the production is related to the surface available for animals in breeding tanks, Breeding in complete cycles can be obtained using various foods, but the quality of diet may markedly affect the characteristics of the vital cycle, such as the length of the fertility period and fecundity. Temperature has a cru­cial effect, chiefly on dynamic preoccesses, that is to say, developmental rate and average generation time. With different...
Tipo: Text Palavras-chave: Production; Dynamique des populations; Biomasse; Composition chimique élémentaire; Bilan énergétique; Copépodes harparcticoïdes; Production; Population dynamic; Biomass; Chemical elementary composition; Energy balance; Hapacticoïd copepods.
Ano: 1979 URL: http://archimer.ifremer.fr/doc/00306/41672/40881.pdf
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Energetic analysis of landrace varieties and hybrids of corn produced in different technological levels of management REA
Araujo,Alisson V. de; Brandão Junior,Delacyr da S.; Colen,Fernando.
The aim of this study was to analyze, under the energetic point of view, the cultivation of corn in three management systems (low, medium and high-tech), using two landrace varieties ('Argentino' and 'BR da Várzea'), a double hybrid cultivar (SHS 4080) and a simple hybrid (IAC 8333). Five performance indicators were used: energy efficiency, liquid cultural energy, cultural efficiency, energy balance and productive energy efficiency. From the perspective of family farming, it was verified the largest social importance of the systems under low and medium levels of technology, due to the increase employment capacity of rural labor. The liquid cultural energy and energy balance were more favorable for the system under high technological level, unlike cultural...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Energy balance; Cultural efficiency; Productive energy efficiency; Sustainability; Zea mays L.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000400004
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Energy analysis of ethanol from sugarcane irrigated with treated domestic sewage Rev. Ciênc. Agron.
Freitas,Cley Anderson Silva de; Bezerra,Francisco Marcus Lima; Silva,Alexandre Reuber Almeida da; Albiero,Daniel; Nascimento,José Adeilson Medeiros do.
ABSTRACT Using energy balance methodology, this study compared the sustainability of ethanol synthesis from sugarcane irrigated with different replacement levels based on the evaporation estimated in a Class A pan (ECA), using treated domestic sewage effluent and groundwater as the water source, in Aquiraz, in the State of Ceará. The adopted statistical design was of randomised blocks in split plots, with four replications. Two water sources (treated sewage effluent and groundwater) were evaluated in the plots, and five irrigation levels (50, 75, 100, 125 and 150% of the ECA) were evaluated in the split plots. Irrigation with treated domestic sewage effluent results in greater energy expenditure. The irrigation depth relative to 150% of the ECA expends the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Reuse of water; Energy balance; Saccharum officinarum L..
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902018000300389
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Energy and Water Use Related to the Cultivation of Energy Crops: a Case Study in the Tuscany Region Ecology and Society
Dalla Marta, Anna; DIPSA-University of Firenze; anna.dallamarta@unifi.it; Natali, Francesca; DIPSA-University of Firenze;; Mancini, Marco; DIPSA-University of Firenze;; Ferrise, Roberto; DIPSA-University of Firenze;; Bindi, Marco; DIPSA-University of Firenze;; Orlandini, Simone; DIPSA-University of Firenze;.
The contribution of agrobiomasses, as a source of energy, to the reduction of greenhouse gas emissions was confirmed by several studies. Biomass from agriculture represents one of the larger and more diverse sources to exploit and in particular ethanol and diesel have the potential to be a sustainable replacement for fossil fuels, mainly for transport purposes. However, the cultivation of energy crops dedicated to the production of biofuels presents some potential problems, e.g., competitiveness with food crops, water needs, use of fertilizers, etc., and the economic, energy, and environmental convenience of such activity depends on accurate evaluations about the global efficiency of the production system. In this study, the processes related to the...
Tipo: Peer-Reviewed Insight Palavras-chave: Agroenergy; Bioethanol; Energy balance; Pure vegetable oil; Water balance.
Ano: 2011
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Energy balance in irrigated wheat in the cerrados region of Central Brazil Scientia Agricola
Luchiari Jr.,A.; Riha,S. J.; Gomide,R.L..
To evaluate the water requirements for irrigated wheat, a micrometeorological study was conducted during the dry seasons of 1982 and 1983 at the Cerrados Agricultural Research Center, Brasilia-DF, Brazil The crop was irrigated when the soil water potential at 5 cm rached -60 to -70J/Kg.Bowen ratio measurements were made on an hourly basis during the entire crop season. Total amount of water evapotranspired during the crop cycle and the energy balance terms varied year to year due to regional advection; In 1982, a less advective year, the total amount of water evapotranspired was 345 mm, with approximately 80% of the net radiation dissipated as latent heat, 13% as a sensible heat and 7% as soil heat after the crop obtained a Leaf Area Index (LAI) of 1.5. In...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Energy balance; Irrigated wheat; Cerrado.
Ano: 1997 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161997000300011
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Energy demand in citrus production under varied operational efficiency values REA
Franco Junior,Nelson C.; Milan,Marcos; Romanelli,Thiago L..
Citrus orchards are very important in Brazil, especially in São Paulo State, where occupy an area of 600,000 ha approximately. To identify sustainability degree of citrus production system, an energy analysis allows evaluating efficiency of direct and indirect applied inputs. Thus, this study aimed to evaluate citrus production system under energetic point of view, in which invested energy is paid back with citrus production; being compared within three scenarios for operational field efficiency. As result, by sensitivity analysis was determined that fuel was the main energy demander, followed by pesticides and fertilizers. In operational work capacity analysis, all combinations between efficiency (minimum, typical and maximum) and yield levels became...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Energy balance; EROI; Machinery management; Sustainability.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000400014
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Energy embodiment in Brazilian agriculture: an overview of 23 crops Scientia Agricola
Veiga,João Paulo Soto; Romanelli,Thiago Libório; Gimenez,Leandro Maria; Busato,Patrizia; Milan,Marcos.
The amount of energy required to produce a commodity or to supply a service varies from one production system to another and consequently giving rise to differing levels of environmental efficiency. Moreover, since energy prices have been continuously increasing over time, this energy amount may be a factor that has economic worth. Biomass production has a variety of end-products such as food, energy, and fiber; thus, taking into account the similarity in end-product of different crops (e.g.: sunflower, peanuts, or soybean for oil) it is possible to evaluate which crops require less energy per functional unit, such as starch, oil, and protein. This information can be used in decision-making about policies for food safety or bioenergy. In this study, 23...
Tipo: Info:eu-repo/semantics/article Palavras-chave: EROI; Starch; Oil; Fertilizer; Fiber; Energy balance.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000600471
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Energy flows in lowland soybean production system in Brazil Ciência Rural
Andrea,Maria Carolina da Silva; Romanelli,Thiago Libório; Molin,José Paulo.
ABSTRACT: Soybean is the main product of Brazilian agribusiness, both production and income. Considering the increase in food and energy demand and the search for more sustainable production systems, this study aimed to analyze inputs and energy use of a possible area of expansion of soybean production: a system under sub irrigation management located in a lowland area of Cerrado biome, northern region of Brazil. Its environmental performance was compared to other Brazilian locations among them traditionally soybean producers. The evaluation and comparison was made through material and energy flow tools in order to determine the inputs embodied per area, as well as energy demand, availability and efficiency in the analyzed production system. Energy demand...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Glycine max (L.) Merr; Material flow; Energy balance; EROI..
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000801395
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Energy performance of a production system of eucalyptus AGRIAMBI
Romanelli,Thiago L.; Milan,Marcos.
Maximizing yields is opposed to the goal of minimizing the use of inputs. In the context of system rationalization, the addition of non-economic parameters in the decision making and the magnitude of eucalyptus plantation in Sao Paulo State, Brazil led to this study. The objective was to establish the flows and to evaluate the performance of energy transformations on eucalyptus production. The evaluated system presented three alternatives of soil acidity management: lime, ash and sludge application. The applied indicators were energy return on investment, energy intensity and energy balance, which meant, respectively, the return over energy investment, the energy content of biomass and the energy obtained per area. For the basic scenario, lime, EROI was...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Sustainability; Environmental analysis; EROI; Energy balance.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662010000800015
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Energy, water and material footprints of agricultural machinery industry CIGR Journal
Mantoam, Edemilson J; Mekonnen, Mesfin M; Romanelli, Thiago Libório.
The intensification of agricultural production systems demand power, supplied by agricultural machinery, besides more agricultural inputs such as fertilizer, pesticides and seeds. Agricultural mechanization provided increase in the global production of food, fiber and bioenergy; and it brought economic benefits to producers, but causing larger energy consumption. Energy embodiment in agricultural machinery has been approached, but data usually are from car industry. This study aimed to determine the energy demand in a plant that assembles five types of agricultural machinery from a multinational manufacturer located in Piracicaba municipality in Sao Paulo state, Brazil. That plant assembles two types of sugarcane harvester, coffee harvesters, sprayers and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Agricultural engineering mechanization; Industrial process; Life cycle assessment; Energy balance; Sustainability.
Ano: 2018 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/4831
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Estimación de la evapotranspiración de un cultivo de vid con apoyo de imagen satelital y validación utilizando Eddy Covariance. Colegio de Postgraduados
Gordillo Salinas, Víctor Manuel.
Experimentalmente, el cálculo de la evapotranspiración se realiza con una precisión razonable usando lisímetros de pesada, técnicas de Eddy Correlation y relación de Bowen. Estos métodos son limitados, ya que proporcionan valores puntuales de evapotranspiración para un lugar en específico y no proporciona la ET a una escala regional. La aplicación de una estimación de la evapotranspiración mediante el uso de mediciones de satélites puede llegar a superar estas limitaciones. El objetivo fue el de utilizar el modelo METRICTM (Mapping Evapotranspiration at High Resolution using Internalized Calibration), para estimar la evapotranspiración mediante un balance de energía, y compararla contra datos medidos en un sistema de Eddy Correlation para el cultivo de...
Palavras-chave: Evapotranspiración; Sensores remotos; Balance de energía; Modelo METRIC TM; Evapotranspiration; Remote sensing; Energy balance; METRIC TM model; Hidrociencias; Maestría.
Ano: 2013 URL: http://hdl.handle.net/10521/1910
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Estimation of soil moisture in the root-zone from remote sensing data Rev. Bras. Ciênc. Solo
Bezerra,Bergson Guedes; Santos,Carlos Antonio Costa dos; Silva,Bernardo Barbosa da; Perez-Marin,Aldrin Martin; Bezerra,Marcus Vinícius Cândido; Bezerra,José Renato Cortez; Rao,Tantravahi Venkata Ramana.
Field-based soil moisture measurements are cumbersome. Thus, remote sensing techniques are needed because allows field and landscape-scale mapping of soil moisture depth-averaged through the root zone of existing vegetation. The objective of the study was to evaluate the accuracy of an empirical relationship to calculate soil moisture from remote sensing data of irrigated soils of the Apodi Plateau, in the Brazilian semiarid region. The empirical relationship had previously been tested for irrigated soils in Mexico, Egypt, and Pakistan, with promising results. In this study, the relationship was evaluated from experimental data collected from a cotton field. The experiment was carried out in an area of 5 ha with irrigated cotton. The energy balance and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Standard relationship; SEBAL; Energy balance; Evaporative fraction; Latent heat flux.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832013000300005
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Estimation of the potential evapotranspiration by a simplified penman method REA
Villa Nova,Nilson A.; Miranda,Jarbas H. de; Pereira,André B.; Silva,Késia O. da.
The numerous methods for calculating the potential or reference evapotranspiration (ETo or ETP) almost always do for a 24-hour period, including values of climatic parameters throughout the nocturnal period (daily averages). These results have a nil effect on transpiration, constituting the main evaporative demand process in cases of localized irrigation. The aim of the current manuscript was to come up with a model rather simplified for the calculation of diurnal daily ETo. It deals with an alternative approach based on the theoretical background of the Penman method without having to consider values of aerodynamic conductance of latent and sensible heat fluxes, as well as data of wind speed and relative humidity of the air. The comparison between the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Crop water use; Bowen ratio; Energy balance.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162006000300007
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Evaluation of a model to Simulate Net Radiation Over a Vineyar cv. Cabernet Sauvignon Chilean J. Agric. Res.
Carrasco,Marcos; Ortega-Farías,Samuel.
Net radiation (Rn) is the main energy balance component controlling evaporation and transpiration processes. In this regard, this study evaluated two models to estimate Rno above a commercial vineyard (Vitis vinifera cv. Cabernet Sauvignon) located in Pencahue Valley, Maule Region (35º22’ S; 71°47’ Wl; 75 m.a.s.l.). An automatic meteorological station (AMS) was installed in the central part of the vineyard and used to measure Rn, solar radiation (Rsi), air temperature (Ta), canopy temperature (Tf) and relative humidity (RH). On a 30 min interval, results indicated that model Rne1 (assuming Ta ≠ Tf) and model Rne2 (assuming Ta = Tf ) were able to estimate Rn with a mean absolute error (MAE) of less than 40 W m-2 and root mean square error (RMSE)...
Tipo: Journal article Palavras-chave: Atmospheric emissivity; Terrestrial radiation; Atmospheric radiation; Energy balance.
Ano: 2008 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000200005
Registros recuperados: 34
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