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Assessing the potentialities of FORMOSAT-2 data for water and crop monitoring at small regional scale in south-eastern France Inra
Courault, D.; Bsaibes, A.; Kpemlie, E.; Hadria, R.; Hagolle, O.; Marloie, O.; Hanocq, J.F.; Olioso, A.; Bertrand, N.; Desfonds, V..
Water monitoring at the scale of a small agricultural region is a key point to insure a good crop development particularly in South-Eastern France, where extremeclimatic conditions result in long dry periods in spring and summer with very sparseprecipitation events, corresponding to a crucial period of crop development. Remotesensing with the increasing imagery resolution is a useful tool to provide information on plant water status over various temporal and spatial scales. The current study focussed on assessing the potentialities of FORMOSAT-2 data, characterized by high spatial (8m pixel)and temporal resolutions (1-3 day/time revisit), to improve crop modeling and spatial estimation of the main land properties. Thirty cloud free images were acquired...
Tipo: Journal Article Palavras-chave: CONTROLE HYDRIQUE SURFACE TEMPERATURE; ALBEDO; LAI; CROP MONITORING; PLANT WATER SATUS; REMOTE SENSING; AGRICUTURAL PRACTICE; WATER MONITORING.
Ano: 2008 URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PROD2008e80e974e&uri=/notices/prodinra1/2008/07/
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Calibration and validation of hyperspectral indices for the estimation of broadleaved forest leaf chlorophyll content, leaf mass per area, leaf area index and leaf canopy biomass Inra
Le Maire, G.; François, C.; Soudani, K.; Berveiller, D.; Pontailler, J.Y.; Breda, N.; Genet, H.; Davi, H.; Dufrêne, E..
This article aims at finding efficient hyperspectral indices for the estimation of forest sun leaf chlorophyll content (CHL, µg cmleaf− 2), sun leaf mass per area (LMA, gdry matter mleaf− 2), canopy leaf area index (LAI, m2leaf msoil− 2) and leaf canopy biomass (Bleaf, gdry matter msoil− 2). These parameters are useful inputs for forest ecosystem simulations at landscape scale. The method is based on the determination of the best vegetation indices (index form and wavelengths) using the radiative transfer model PROSAIL (formed by the newly-calibrated leaf reflectance model PROSPECT coupled with the multi-layer version of the canopy radiative transfer model SAIL). The results are tested on experimental measurements at both leaf and canopy scales. At the...
Tipo: Journal Article Palavras-chave: MICROONDE; TENEUR EN CHLOROPHYLLE; MODELISATION CHLOROPHYLL; LMA; SLA; LEAF BIOMASS; EO1 HYPERION; ASD FIELDSPEC; LAI; PROSPECT; SAIL; PROSAIL.
Ano: 2008 URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PROD20093213d823&uri=/notices/prodinra1/2009/01/
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Estrutura do dossel e acúmulo de forragem de Brachiaria brizantha cultivar Xaraés em resposta a estratégias de pastejo. Repositório Alice
PEDREIRA, B.C. e; PEDREIRA, C.G.S.; SILVA, S.C. da.
O objetivo deste trabalho foi avaliar o desempenho agronômico do capim-xaraés [Brachiaria brizantha (A. Rich.) Stapf. cv. Xaraés] em resposta a três estratégias de pastejo rotacionado: uma baseada no calendário (pastejo a cada 28 dias) e duas em função da interceptação luminosa (IL) pelo dossel (pastejo iniciado a 95% ou 100% de IL). No tratamento 95% de IL, a altura média pré-pastejo foi 29,5 cm; no 100% de IL, foi 41,6 cm e no 28 dias, 34,2 cm. A altura média pós-pastejo foi 14,6 cm em todos os tratamentos, e correspondeu a um índice de área foliar médio de 0,73, IL de 42% e ângulo da folhagem de 65,2º. No pré-pastejo, o ângulo da folhagem não variou com as estratégias de pastejo e correspondeu a um valor médio de 41,6º. A altura do dossel e a IL...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Interceptação luminosa; IAF; Ângulos foliares; Pastejo rotacionado; Light interception; LAI; Leaf angle; Rotational grazing.
Ano: 2007 URL: http://www.alice.cnptia.embrapa.br/handle/doc/121838
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Growth dynamics and yield of melon as influenced by nitrogen fertilizer Scientia Agricola
Castellanos,María Teresa; Cabello,María Jesús; Cartagena,María del Carmen; Tarquis,Ana María; Arce,Augusto; Ribas,Francisco.
Nitrogen (N) is an important nutrient for melon (Cucumis melo L.) production. However there is scanty information about the amount necessary to maintain an appropriate balance between growth and yield. Melon vegetative organs must develop sufficiently to intercept light and accumulate water and nutrients but it is also important to obtain a large reproductive-vegetative dry weight ratio to maximize the fruit yield. We evaluated the influence of different N amounts on the growth, production of dry matter and fruit yield of a melon 'Piel de sapo' type. A three-year field experiment was carried out from May to September. Melons were subjected to an irrigation depth of 100% crop evapotranspiration and to 11 N fertilization rates, ranging 11 to 393 kg ha-1 in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: LAI; LAD; Dry matter accumulation; Production functions; Leaf nitrogen concentration.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162011000200009
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LAI Improved to dry forest in Semiarid of the Brazil. Repositório Alice
GALVÍNCIO, J. D.; MOURA, M. S. B. de; SILVA, T. G. F. da; SILVA, B. B. da; NAUE, C. R..
Savannas are globally important ecosystems of great significance to human economies. Savannas exist in water-limited regions which forces tree canopies open and heterogeneous. The open canopy structure allows grass to co-dominate in the savannas by occupying different niches in space and time. Leaf area index (LAI) and fraction of photosynthetically active radiation absorbed by vegetation (FPAR) characterize vegetation canopy functioning and energy absorption capacity. LAI and FPAR are key parameters in most ecosystem productivity models and global models of climate, hydrology, biogeochemistry and ecology. Given the above, this study aimed to develop an equation of LAI calibrated by savannah in semiarid northeastern Brazil and proposed a model to better...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: LAI; Caatinga; Ecossistemas secos; Modelo de desenvolvimento; Fieldspec; Savanas; Recurso natural; Sensoriamento remoto; Natural resource.
Ano: 2013 URL: http://www.alice.cnptia.embrapa.br/handle/doc/974172
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Phytomass mapping of the "seridó caatinga" vegetation by the plant area and the normalized difference vegetation indeces Scientia Agricola
Costa,Thomaz Corrêa e Castro da; Accioly,Luciano José de Oliveira; Oliveira,Maria Ap. José de; Burgos,Nivaldo; Silva,Flávio Hugo Barreto Batista da.
Phytomass is a critical information for economic and environmental activities like the establishment of policies for timber resources, forest management, studies of plant nutrient cycling, CO2 sink, among other. The phytomass of a Caatinga area was obtained by an empirical method using normalized difference vegetation index (NDVI) of Landsat images, the plant area index (PAI) and the phytomass inventory. At a first stage, linear, logarithmic and non-linear models were developed and tested. Bush and tree specimens were considered in the study, so that most of the individuals that contribute to the spectral answer detected by satellite images were included. At a second stage, the orbital parameter NDVI was used to map the PAI, which was used to map the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: CO2; LAI; Aboveground biomass; Desertification.
Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162002000400014
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Remote sensing and detection of nitrogen status in crops. Application to precise nitrogen fertilization Inra
Guerif, M.; Houlès, V.; Baret, F..
Remote sensing techniques offer a unique solution for mapping the growth and nitrogen status of crops and monitoring its time course. Therefore these maps are powerful tools for recommending spatially precise cultural practices, and particularly nitrogen dressing. In this paper, we review the main issues to be addressed for estimating crop variables from remote sensing and for using them for managing variable rate fertilizer application.The derivation of canopy state variables such as the leaf area index (LAI) and chlorophyll content (Cab) is first addressed. It is demonstrated that the inversion of radiative transfer models leads to useful estimates of these variables. However, because of the ill-posed nature of the inverse problem, better accuracy is...
Tipo: Meeting Paper Palavras-chave: CHLOROPHYLLE NITROGEN; CHLOROPHYLL; LEAF AREA INDEX; LAI; FERTILIZATION; REMOTE SENSING; CROP MODEL; PRECISION AGRICULTURE.
Ano: 2007 URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PROD200795287ab1&uri=/notices/prodinra1/2010/11/
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Remote Sensing for Site-Specific Crop Management: Evaluating the Potential of Digital Multi-Spectral Imagery for Monitoring Crop Variability and Weeds within Paddocks AgEcon
Drysdale, G.; Metternicht, G..
This paper analyses the potential and limitations of airborne remote sensing systems for detecting crop growth variability and weed infestation within paddocks at specified capture times. The detection of areas of crop growth variability can help farmers become aware of regions within their paddock where they may be experiencing above and below average yields due to changes in soil or management conditions. For instance, the early detection of weed infestation within cereal crops is crucial for lessening their impact on the final yield. Transect sampling within a canola paddock of a broad acre agricultural property in the South West of Western Australia was conducted synchronous with the capture of 1m spatial resolution DMSI. The four individual bands...
Tipo: Conference Paper or Presentation Palavras-chave: LAI; Remote sensing; Crop density; Vegetation indices; Weed mapping.; Crop Production/Industries.
Ano: 2003 URL: http://purl.umn.edu/24341
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Surface energy exchange and evapotranspiration from cotton crop under full irrigation conditions in the Rio Grande do Norte State, Brazilian Semi-Arid Bragantia
Bezerra,Bergson Guedes; Bezerra,José Renato Cortez; Silva,Bernardo Barbosa da; Santos,Carlos Antonio Costa dos.
The main objectives of this study were documenting how energy balance partitioning and ET vary seasonally along each growth season of cotton crop under full irrigation conditions in the Brazilian semiarid. The studied area was located in the Apodi Plateau, which is located on west of Rio Grande do Norte state and is an area with extensive agricultural suitability and semiarid climate. Micrometeorological measurements were taken during cotton growth season on dry seasons of 2008 and 2009 years in a cotton crop field of about 5 ha, and the energy balance components were derived from Bowen Ratio Energy Balance (BREB) method. The obtained results revealed important role of the vegetative growth of cotton crop in the energy balance partitioning. The values of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Bowen ratio energy balance; LAI.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052015000100120
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Tiller size/population density compensation in grazed Coastcross bermudagrass swards Scientia Agricola
Sbrissia,André Fischer; Silva,Sila Carneiro da; Carvalho,Carlos Augusto Brandão de; Carnevalli,Roberta Aparecida; Pinto,Luiz Felipe de Moura; Fagundes,Jaílson Lara; Pedreira,Carlos Guilherme Silveira.
Several compensatory mechanisms in pastures do not allow optimisation of responses from the processes of herbage production and utilisation. Compensation due to tiller size/density relationships is one of these mechanisms. This experiment evaluated this process for Coastcross bermudagrass and compared the responses to those reported for temperate forages. Treatments were "steady state" sward surface heights of 5, 10, 15, and 20 cm that were maintained from August, 1998, through July, 1999 by sheep grazing. The experimental design was a randomised complete block, replicated four times. Pasture responses were evaluated on four separate dates (15/12/1998, 25/01/1999, 07/04/1999 and 04/07/1999) with respect to: tiller population density, tiller weight, leaf...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cynodon; LAI; Tiller; Morphology.
Ano: 2001 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162001000400002
Registros recuperados: 10
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