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Registros recuperados: 17
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Aboveground biomass in Prosopis pallida (Humb. and Bonpl. ex Willd.) H. B. K. ecosystems using Landsat 7 ETM+ images RChHN
PADRÓN,EVA; NAVARRO-CERRILLO,RAFAEL M.
The significance of field work in remote sensing studies when applied to large areas has often been underestimated. The combination of specific forest inventories for the estimation of aboveground biomass in large dry tropical forest areas with remote sensor data has scarcely been explored to date. In this work, a systematic, stratified forest inventory involving 100 X 100 m square plots in an area of Peruvian Prosopis pallida dry forest, roughly one million hectares in size in the Piura province (Peru) has been compiled. The inventory encompassed the principal silvicultural variables defining the ecosystem studied, which were used in allometric equations for the different species, genera and plant associations in the area in order to estimate the amount...
Tipo: Journal article Palavras-chave: Prosopis pallida; Landsat 7 ETM+; Vegetation indices; Biomass estimation.
Ano: 2007 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2007000100004
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Aplicación de tecnologías de percepción remota en la estimación de rendimientos en caña de azúcar. Colegio de Postgraduados
Zenteno Cruz, Guillermo Alberto.
Los productores de caña de azúcar buscan constantemente formas de reducir costos, aumentar la productividad y los rendimientos, pero en general, son pocas las herramientas que se están aplicando para tal fin. Por otra parte, es cada vez más importante la predicción temprana del rendimiento de los cultivos que permita una planificación de políticas agrícolas y de seguridad alimentaria en una economía de mercado globalizado. Con el propósito de calibrar una metodología para enfrentar estos problemas, la presente investigación se llevó a cabo en la zona de abasto del Ingenio Emiliano Zapata, en Morelos, México, en una superficie de 10, 664 hectáreas, durante el ciclo agrícola 2009-2010. El propósito del estudio fue determinar una función matemática para...
Palavras-chave: Predicción temprana; Indices de vegetación; Estrés hídrico; Evapotranspiración; Saccharum officinarum; Early prediction; Vegetation indices; Water stress; Evapotranspiración; Maestría; Hidrociencias.
Ano: 2012 URL: http://hdl.handle.net/10521/737
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Assessing biophysical variable parameters of bean crop with hyperspectral measurements Scientia Agricola
Monteiro,Priscylla Ferraz Câmara; Angulo Filho,Rubens; Xavier,Alexandre Cândido; Monteiro,Rodrigo Otávio Câmara.
Recently high spectral resolution sensors have been developed, which allow new and more advanced applications in agriculture. Motivated by the increasing importance of hyperspectral remote sensing data, the need for research is important to define optimal wavebands to estimate biophysical parameters of crop. The use of narrow band vegetation indices (VI) derived from hyperspectral measurements acquired by a field spectrometer was evaluated to estimate bean (Phaseolus vulgaris L.) grain yield, plant height and leaf area index (LAI). Field canopy reflectance measurements were acquired at six bean growth stages over 48 plots with four water levels (179.5; 256.5; 357.5 and 406.2 mm) and tree nitrogen rates (0; 80 and 160 kg ha-1) and four replicates. The...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Hyperspectral remote sensing; Spectroradiometry; Vegetation indices.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162012000200001
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Biometric characteristics and canopy reflectance association for early-stage sugarcane. Repositório Alice
ROCHA, M. G. da; BARROS, F. M. M. de; OLIVEIRA, S. R. de M.; AMARAL, L. R. do.
ABSTRACT: Knowing the spatial variability of sugarcane biomass in the early stages of development may help growers in their management decision-making. Proximal canopy sensing is a promising technology that can identify this variability but is limited to quantifying plant-specific parameters. In this study, we evaluated whether biometric variables integrated with canopy reflectance data can assist in the generation of models for early-stage sugarcane biomass prediction. To substantiate this assertion, four sugarcane-producing fields were measured with an active crop canopy sensor and 30 sampling plots were selected for manually quantifying chlorophyll content, plant height, stalk number and aboveground biomass. We determined that Random Forest and Multiple...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Floresta aleatória; Índice de vegetação; Mineração de dados; Precision farming; Random forest; Vegetation indices; Data mining; Canopy sensor; Biomassa; Cana de Açúcar; Agricultura de Precisão; Biomass; Sugarcane; Precision agriculture; Vegetation index.
Ano: 2019 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1110823
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Biometric characteristics and canopy reflectance association for early-stage sugarcane biomass prediction Scientia Agricola
Rocha,Murillo Grespan da; Barros,Flávio Margarito Martins de; Oliveira,Stanley Robson de Medeiros; Amaral,Lucas Rios do.
ABSTRACT: Knowing the spatial variability of sugarcane biomass in the early stages of development may help growers in their management decision-making. Proximal canopy sensing is a promising technology that can identify this variability but is limited to quantifying plant-specific parameters. In this study, we evaluated whether biometric variables integrated with canopy reflectance data can assist in the generation of models for early-stage sugarcane biomass prediction. To substantiate this assertion, four sugarcane-producing fields were measured with an active crop canopy sensor and 30 sampling plots were selected for manually quantifying chlorophyll content, plant height, stalk number and aboveground biomass. We determined that Random Forest and Multiple...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Random forest; Canopy sensor; Vegetation indices; Precision farming; Data mining.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162019001400274
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Correlation maps to assess soybean yield from EVI data in Paraná State, Brazil Scientia Agricola
Figueiredo,Gleyce Kelly Dantas Araújo; Brunsell,Nathaniel Allan; Higa,Breno Hiroyuki; Rocha,Jansle Vieira; Lamparelli,Rubens Augusto Camargo.
ABSTRACT Vegetation indices are widely used to monitor crop development and generally used as input data in models to forecast yield. The first step of this study consisted of using monthly Maximum Value Composites to create correlation maps using Enhanced Vegetation Index (EVI) from Moderate Resolution Imaging Spectroradiometer (MODIS) sensor mounted on Terra satellite and historical yield during the soybean crop cycle in Paraná State, Brazil, from 2000/2001 to 2010/2011. We compared the ability of forecasting crop yield based on correlation maps and crop specific masks. We ran a preliminary regression model to test its ability on yield estimation for four municipalities during the soybean growing season. A regression model was developed for both...
Tipo: Info:eu-repo/semantics/article Palavras-chave: MODIS; Crop yield forecasting; Vegetation indices.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162016000500462
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Geotecnologias aplicadas no monitoramento da cultura da soja. Repositório Alice
ANTUNES, J. F. G..
O objetivo do trabalho é monitorar a cultura da soja entre os meses de janeiro e abril de 2007 nos estados do Paraná e do Rio Grande do Sul, utilizando composições máximas de NDVI/ AVHRR- NOAA, obtidas automaticamente por meio de geotecnologias.
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Processamento de imagens; Georreferenciamento preciso; Composições de máximo valor; Índices de vegetação; Previsão de safras; Image processing; Precision georeferencing; Maximum Value Compositie; Vegetation indices; Harvest forecast; Sensoriamento Remoto; Remote sensing; Image analysis; Vegetation index.
Ano: 2007 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/9549
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Hyperspectral field reflectance measurements to estimate wheat grain yield and plant height Scientia Agricola
Xavier,Alexandre Cândido; Rudorff,Bernardo Friedrich Theodor; Moreira,Mauricio Alves; Alvarenga,Brummer Seda; Freitas,José Guilherme de; Salomon,Marcus Vinicius.
Hyperspectral crop reflectance data are useful for several remote sensing applications in agriculture, but there is still a need for studies to define optimal wavebands to estimate crop biophysical parameters. The objective of this work is to analyze the use of narrow and broad band vegetation indices (VI) derived from hyperspectral field reflectance measurements to estimate wheat (Triticum aestivum L.) grain yield and plant height. A field study was conducted during the winter growing season of 2003 in Campinas, São Paulo State, Brazil. Field canopy reflectance measurements were acquired at six wheat growth stages over 80 plots with four wheat cultivars (IAC-362, IAC-364, IAC-370, and IAC-373), five levels of nitrogen fertilizer (0, 30, 60, 90, and 120 kg...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Remote sensing; Agriculture; Vegetation indices.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000200004
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Mapping climatic risks in the EU agriculture AgEcon
Gallego, Javier; Conte, Costanza G.; Dittmann, Christoph; Stroblmair, Josef; Bielza, Maria.
Replaced with revised version of paper 11/18/08.
Tipo: Conference Paper or Presentation Palavras-chave: Agrometeorological models; Climatic risk; European Union; Vegetation indices; Environmental Economics and Policy; Risk and Uncertainty.
Ano: 2007 URL: http://purl.umn.edu/9260
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Multispectral remote sensing for site-specific nitrogen fertilizer management PAB
Bagheri,Nikrooz; Ahmadi,Hojjat; Alavipanah,Seyed Kazem; Omid,Mahmoud.
The objective of this work was to evaluate the use of multispectral remote sensing for site-specific nitrogen fertilizer management. Satellite imagery from the advanced spaceborne thermal emission and reflection radiometer (Aster) was acquired in a 23 ha corn-planted area in Iran. For the collection of field samples, a total of 53 pixels were selected by systematic randomized sampling. The total nitrogen content in corn leaf tissues in these pixels was evaluated. To predict corn canopy nitrogen content, different vegetation indices, such as normalized difference vegetation index (NDVI), soil-adjusted vegetation index (Savi), optimized soil-adjusted vegetation index (Osavi), modified chlorophyll absorption ratio index 2 (MCARI2), and modified triangle...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Aster; Nitrogen content; Near infrared; Multispectral response; Precision agriculture; Vegetation indices.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2013001000011
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Relationship between remote sensing data and field-observed interril erosion PAB
Moraes,André Geraldo de Lima; Carvalho,Daniel Fonseca de; Antunes,Mauro Antonio Homem; Ceddia,Marcos Bacis.
Abstract: The objective of this work was to evaluate the relationship between different remote sensing data, derived from satellite images, and interrill soil losses obtained in the field by using a portable rainfall simulator. The study was carried out in an area of a hydrographic basin, located in Médio Paraíba do Sul, in the state of Rio de Janeiro - one of the regions most affected by water erosion in Brazil. Evaluations were performed for different vegetation indices (NDVI, Savi, EVI, and EVI2) and fraction images (FI), derived from linear spectral mixture analysis (LSMA), obtained from RapidEye, Sentinel2A, and Landsat 8 OLI images. Vegetation indices are more adequate to predict soil loss than FI, highlighting EVI2, whose exponential model showed R2...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Linear spectral mixing analysis; Rainfall simulator; Vegetation indices.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2018000300332
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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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Role of soil carbon in the landscape functioning of the Alto São Bartolomeu watershed in the Cerrado region, Brazil PAB
Alves,Ray Pinheiro; Couto Junior,Antonio Felipe; Martins,Eder de Souza; Nardoto,Gabriela Bielefeld.
Abstract The objective of this work was to evaluate the effect of soil carbon on landscape functioning of the Oxisols covering the plateaus of the Alto São Bartolomeu watershed, in the Cerrado (Brazilian savanna) region of Central Brazil. Soil organic carbon (SOC) concentration, carbon stocks, and some soil physical and chemical characteristics were determined at the 0-0.20-m depth on native and anthropogenic areas. Soils from cerrado stricto sensu patches were similar both physically and chemically, being affected by exchangeable Al3+ and by SOC concentrations, while anthropogenic matrices were affected by soil bulk density, pH, extractable P, and exchangeable Ca2+ and Mg2+. The estimate of spatial distribution of soil carbon better fitted had an adjusted...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Brazilian savanna; No-tillage; Oxisol; Pasture; Pedotransfer function; Vegetation indices.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901241
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Spectral characterization of forest plantations with Landsat 8/OLI images for forest planning and management PAB
Alba,Elisiane; Mello,Eliziane Pivotto; Marchesan,Juliana; Silva,Emanuel Araújo; Tramontina,Juliana; Pereira,Rudiney Soares.
Abstract: The objective of this work was to evaluate the use of Landsat 8/OLI images to differentiate the age and estimate the total volume of Pinus elliottii, in order to determine the applicability of these data in the planning and management of forest activity. Fifty-three sampling units were installed, and dendrometric variables of 9-and-10-year-old P. elliottii commercial stands were measured. The digital numbers of the image were converted into surface reflectance and, subsequently, vegetation indices were determined. Red and near-infrared reflectance values were used to differentiate the ages of the stands. Regression analysis of the spectral variables was used to estimate the total volume. Increase in age caused an addition in reflectance in the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Pinus elliottii; Remote sensing; Vegetation indices; Volume modeling..
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2017001101072
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SURFACE ENERGY BALANCE SYSTEM (SEBS) AND SATELLITE DATA FOR MONITORING WATER CONSUMPTION OF IRRIGATED SUGARCANE REA
Ferreira,Elizabeth; Mannaerts,Christiaan M.; Dantas,Antonio A.; Maathuis,Bernardus H..
ABSTRACT The objective of this research was to evaluate the water consumption of irrigated sugarcane areas using the Surface Energy Balance System (SEBS) driven by products derived from Meteosat Second Generation (MSG), SPOT/VEGETATION, Terra/MODIS satellite data and meteorological observations data from Minas Gerais State, Brazil. The actual evapotranspiration from SEBS model (ET-SEBS) was compared against crop evapotranspiration under standard conditions (ETc), which was obtained from weather data based on reference evapotranspiration (ET0) and the crop coefficient (Kc) values from FAO. Results showed that there was a good agreement between ET-SEBS and ETc when sugarcane was at maximum development stage under center pivot irrigation and the Kc value...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Crop coefficient; Evapotranspiration; Irrigation; Remote sensing; Vegetation indices.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162016000601176
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Using an aerial system of remote sensing to detect different nutritional status in Brachiaria decumbens REA
Silva Júnior,Mário C. da; Pinto,Francisco de A. De C.; Queiroz,Daniel M. de; Vieira,Luciano B.; Resende,Ricardo C. de.
The aim of this study was to use digital images acquired by cameras attached to a helium balloon to detect variation of the nutritional status in Brachiaria decumbens. The treatments consisted of five doses of nitrogen (0, 50, 100, 150 e 200kg ha-1) with six replications each, evaluated in a completely randomized statistical design. A remote sensing system composed of digital cameras and microcomputers was used for image acquisition, and a helium balloon lifted the cameras to the heights of 15, 20, 25 and 30m. A portable chlorophyll meter and analyses of leaf nitrogen content were used to make comparisons with data obtained by the remote sensing system. Data was acquired in two phases, in different climatic conditions. At the end of each phase, dry matter...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Digital images; Vegetation indices; Nitrogen.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000500016
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Variáveis e modelos para estimativa da produtividade do cafeeiro a partir de índices de vegetação derivados de imagens Landsat. Repositório Alice
BERNARDES, T.; MOREIRA, M. A.; VERONA, J. D.; SHIMABUKURO, Y. E.; LUIZ, A. J. B..
Abstract. Coffee fields present a specific pattern of productivity resulting in high and low production in alternated years. Branches grown the first phenological year will produce coffee beans the second phenological year. In high-production years a plant works mostly to grain-filling to the detriment of new branches which will be responsible for production the following year. In low-production years the plant works rather to grow new branches which will produce beans the subsequent year. This feature can be related to the foliar biomass, which can be estimated through remote sensing derived vegetation indices. Several studies report this feature must be incorporated in modeling coffee yield coupled with agrometeorogical models. In this paper we derived...
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Coffee yield; Biophysics variables; Vegetation indices; Radiometric correction; Stepwise regression; Café; Produtividade; Sensoriamento remoto; Coffee; Grain yield; Agricultural management models; Statistical models.
Ano: 2013 URL: http://www.alice.cnptia.embrapa.br/handle/doc/963264
Registros recuperados: 17
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