Consulta: subjectFacets:"Eddy covariance"
Registros recuperados: 9
Data/hora: 10/06/2024 09:30:11

South African carbon observations: CO2 measurements for land, atmosphere and ocean
Provedor de dados: 5
Autores: Feig, Gregor T.; Joubert, Warren R.; Mudau, Azwitamisi E.; Monteiro, Pedro M. S.
Tipo: Text
Palavras-chave: PCO(2); Eddy covariance; Carbon reporting; Carbon flux.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00662/77391/79074.pdf

Using Scintillometry to Estimate Sensible Heat Fluxes over Water: First Insights
Provedor de dados: 5
Autores: Bouin, Marie-noelle; Legain, D.; Traulle, O.; Belamari, S.; Caniaux, G.; Fiandrino, Annie; Lagarde, Franck; Barrie, J.; Moulin, E.; Bouhours, G.
An extra large aperture scintillometer (XLAS) was used over several months across the Thau Lagoon (South of France) to retrieve one-wavelength scintillation and, thence, sensible heat flux. We present the experiment with the XLAS, an eddy-covariance station and meteorological stations measuring on or near the Thau Lagoon. Changes implemented to adapt the scintillometry processing schemes to the above water conditions are presented together with a full error budget, including sensitivity tests to the relevant parameters of the scintillometer processing scheme. The XLAS error budget amounts to 16% (systematic part) +/- 50% (random part). Sensible heat fluxes obtained using the XLAS under unstable atmospheric conditions are then compared to eddy-covariance...
Tipo: Text
Palavras-chave: Air-sea fluxes; Eddy covariance; Footprint; Monin-Obukhov similarity theory; Scintillometry; Sensible heat flux.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00085/19621/17483.pdf

Balanço de energia e controle biofísico da evapotranspiração na Caatinga em condições de seca intensa
Provedor de dados: 86
Autores: Souza,Luciana Sandra Bastos de; Moura,Magna Soelma Beserra de; Sediyama,Gilberto Chohaku; Silva,Thieres George Freire da.
Resumo:O objetivo deste trabalho foi determinar a variação sazonal dos componentes do balanço de energia e avaliar o controle biofísico da evapotranspiração, em área de Caatinga preservada, em condições de seca intensa. O experimento foi conduzido em 2012, tendo-se utilizado o sistema "eddy covariance", instalado a 16,9 m acima da superfície do solo. Além disso, foram realizadas medidas de temperatura, umidade, radiação solar, saldo de radiação, fluxo de calor no solo e temperatura do solo. Os dados dos fluxos de calor sensível e latente foram processados com o programa Alteddy e analisados em escalas diária e sazonal. Com os dados do fluxo de calor latente, foram determinados os valores da evapotranspiração, bem como os indicadores da sua sensibilidade às...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Eddy covariance; Fator de desacoplamento; Fluxo de calor sensível; Resistência de superfície; Vegetação natural.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2015000800627

Energy balance measurements over a banana orchard in the Semiarid region in the Northeast of Brazil
Provedor de dados: 86
Autores: Santos,Carlos Antonio Costa dos; Silva,Bernardo Barbosa da; Rao,Tantravahi Venkata Ramana; Neale,Christopher Michael Usher.
The objective of this work was to evaluate the reliability of eddy covariance measurements, analyzing the energy balance components, evapotranspiration and energy balance closure in dry and wet growing seasons, in a banana orchard. The experiment was carried out at a farm located within the irrigation district of Quixeré, in the Lower Jaguaribe basin, in Ceará state, Brazil. An eddy covariance system was used to measure the turbulent flux. An automatic weather station was installed in a grass field to obtain the reference evapotranspiration (ET0) from the combined FAO-Penman-Monteith method. Wind speed and vapor pressure deficit are the most important variables on the evaporative process in both growing seasons. In the dry season, the heat fluxes have a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Musa; Dry season; Eddy covariance; Latent heat flux; Sensible heat flux; Wet season.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2009001100001

Relación entre los componentes del balance de energía y la resistencia estomática en el cultivo de melón bajo acolchado plástico: (con 2 figuras y 1 cuadro)
Provedor de dados: 85
Autores: Munguia,J; Zermeño,A; Quezada,R; De La Rosa,M; Ibarra,L; Torres-B,A.
This study analyzes the relationship between the changes in the energy balance components and the muskmelon stomatal resistance under plastic mulch conditions. This experiment was conducted in a muskmelon crop with and without plastic mulch, from April to July, 1998. To measure the energy balance components (net radiation (Rn), latent heat flux LE, sensible heat flux H and surface soil flux G). Eddy covariancestations were used; one was located in the plastic mulch section and the otherin the section withno plastic mulch.Each stationconsisted offast response kryptonhygrometer, aonedimensionalsonic anemometer anda fine wirethermocouple. The stations also have a net radiometer, 2 soil heat flux plates and two soil thermocouples of 4 parallel ends. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Muskmelon; Eddy covariance; Energy balance; Stomatal resistance.
Ano: 2004
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-56572004000100022

Maximum leaf photosynthetic light response for three species in a transitional tropical forest in Southern Amazonia
Provedor de dados: 91
Autores: Miranda,Eduardo J.; Priante Filho,Nicolau; Priante,Pedro C.; Campelo Jr.,José H.; Suli,George S.; Fritzen,Clóvis L.; Nogueira,José de S.; Vourlitis,George L.
Measurements of CO2 and water vapor flux using eddy covariance are being made from a 40 m tower located in a transitional tropical forest near Sinop Mato Grosso. As complementary information to this study, the photosynthetic light response curves of three species located near the tower were measured at different heights in the forest canopy and light conditions with the objective of understanding seasonal and spatial (height in the forest canopy and gap or shade located plants) trends in the photosynthetic light response. The measurements were made in a canopy emergent tree (30 m tall) identified as Brosimum lactescens, and in two relatively short plants (0.6 to 1.6 m height) identified as Quiina pteridophylla and Diniszia excelsa located in different...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Eddy covariance; Tropical forest; Photosynthetic light.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662004000100024

Daily and seasonal patterns of CO2 fluxes and evapotranspiration in maize-grass intercropping
Provedor de dados: 91
Autores: Machado,Cássia B.; Lima,José R. de S.; Antonino,Antonio C. D.; Souza,Eduardo S. de; Souza,Rodolfo M. S.; Alves,Edevaldo M.
ABSTRACT Studies that investigate the relationships between CO2 fluxes and evapotranspiration (ET) are important for predicting how agricultural ecosystems will respond to climate changes. However, none was made on the maize-grass intercropping system in Brazil. The aim of this study was to determine the ET and CO2 fluxes in a signal grass pasture intercropped with maize, in São João, Pernambuco, Brazil, in a drought year. Furthermore, the soil water storage (SWS) and leaf area index (LAI) were determined. The latent heat flux was the main consumer of the available energy and the daily and seasonal ET and CO2 variations were mainly controlled by rainfall, through the changes in soil water content and consequently in SWS. The agroecosystem acted as an...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Eddy covariance; Carbon; Climate change.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000900777

Energy, water vapor and carbon fluxes in Andean agroecosystems: conceptualization and methodological standardization
Provedor de dados: 109
Autores: Castano-Marín,Angela María; Riaño-Herrera,Nestor Miguel; Peña-Quiñones,Andrés Javier; Ramirez-Builes,Víctor Hugo; Valencia-Salazar,Arley; Figueroa-Casas,Apolinar; Góez-Vinasco,Gerardo Antonio.
Abstract This paper presents the conceptualization, methodological adjustment and experimental application of the micrometeorological technique eddy covariance - EC, to measure energy, water vapor and CO2 fluxes in two coffee agroecosystems: the first under full sunlight, and the second under shade, both with equatorial Andean hillslope conditions. With a footprint and fetch calculation, the required distance from the edge of the field in the prevailing wind direction to the EC tower is three times higher under shade than full sun. The shaded agroecosystem reached maximum average carbon fixation rates of 21.26 ± 2.469 μmolCO2.m-2s-1 (α = 0.05) (61% higher than under 100% sunlight) which gives a high carbon sink capacity to the association of coffee plants...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Agroecosystem coffee; Andean hillslope; Eddy covariance; Energy fluxes; Gas exchange.
Ano: 2017
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122017000100027

Evaluation of OSEB and SEBAL models for energy balance of a crop area in a humid subtropical climate
Provedor de dados: 53
Autores: Schirmbeck,Juliano; Fontana,Denise Cybis; Roberti,Débora Regina.
ABSTRACT This study evaluated the adequacy of the One-Source Energy Balance (OSEB) and Surface Energy Balance Algorithm for Land (SEBAL) models to estimate evapotranspiration in grain growing areas with humid subtropical climate in Rio Grande do Sul, southern Brazil. The dataset was obtained from a micrometeorological station (Eddy Covariance) and MODIS (Moderate Resolution Imaging Spectroradiometer) products during 84 observation days between 2009 and 2011. The OSEB and SEBAL models were used to estimate the partition of net radiation (Rn) into the components latent heat flux (LE), sensible heat flux (H), and ground heat flux (G) estimated from the MODIS images while the experimental data measured in situ were used to compare the results. Analyses...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Latent heat flux; Eddy covariance; MODIS images.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052018000400609