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Performance of the SunScan canopy analysis system in estimating leaf area index of maize CIGR Journal
Philip Gbenro Oguntunde; The Federal University of Technology, Akure; olawale J. Olukunle; The Federal University of Technology, Akure; Johnson T. Fasinmirin; The Federal University of Technology, Akure; Oluremi A. Abiolu; The Federal University of Technology, Akure.
Rapid and reliable estimates of leaf area index (LAI) are important for studies of exchanges of energy and gases in the biosphere-atmosphere continuum.  This paper evaluates the field performance of SunScan canopy analysis system for rapid estimation of LAI.  Direct and indirect measurements of LAI were made in a maize (Zea mays L.) field at four phenological stages (emergence, vegetative, flowering and physiological maturity) at a tropical site in Ghana during the Glowa Vota Project field campaign (www.glowa-volta.de).  Similar measurements were repeated in early and late planting seasons with similar crop management practices.  The result showed a generally good performance of this sensor at all the phenological stages.  Average LAI from the sensor...
Palavras-chave: Agricultural and Biosystems Engineering SunScan probe; Field evaluation; Leaf area index; Maize; Ghana.
Ano: 2012 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/1823
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Commercial Digital Camera to Estimate Postharvest Leaf Area Index in Vitis vinifera L. cv. Cabernet Sauvignon on a Vertical Trellis Chilean J. Agric. Res.
Espinosa L.,Miguel; Acuña C.,Eduardo; Espinosa B.,Miguel; Barrera B.,Juan.
The leaf area index (LAI) of a vineyard (Vitis vinifera L.) cv. Cabernet Sauvignon located in the commune of Cauquenes, Maule Region in Chile, was estimated from digital images obtained with a commercial camera using two indirect methods: Leaf Area Gap and Brightness (LAGB) and -Photogrammetric Leaf Area Quantification System (PLAQS). The latter requires deleafing of the grapevine. In a normalized difference vegetation index (NDVI) map, three points of vine vigor were selected: high, medium, and low for which horizontal and vertical images were obtained. Images were filtered with the Arc View GIS 3.1 program to provide only leaf images and corresponding pixel numbers. Image area and square meters per linear meter were calculated. The best models were...
Tipo: Journal article Palavras-chave: Vitis vinifera; Leaf area index; Digital image; Photographic camera.
Ano: 2010 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200015
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Growth and yield of rice cultivars sowed on different dates under tropical conditions Ciencia e Investigación Agraria
Garcés-Varon,Gabriel; Restrepo-Díaz,Hermann.
Rice plants are susceptible to low light or high temperature conditions during the reproductive and maturity stages. Two rice cultivars, Fedearroz 50 ('F50') and Fedearroz 733 ('F733'), were planted on three planting dates, January 1st (PD1), February 15th (PD2) and April 1st (PD3), to expose them to different climatic conditions during the different stages of rice development. The experiment was a factorial arrangement. Of the various weather parameters, solar radiation fluctuated the most among the three different planting dates, with PD1 having the highest number of days with values ≥ 450 cal·cm-2·d-1. The yield components were influenced by the planting time. PD3 showed the lowest number of tillers per unit of area and the highest percentage...
Tipo: Journal article Palavras-chave: Grain yield; Leaf area index; Planting date; Rice; Solar radiation; Tillers; Unfilled Spikelet percentage.
Ano: 2015 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202015000200008
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Almacenamiento de carbono en bosques manejados de pinus patula: Estimación mediante percepción remota Colegio de Postgraduados
Aguirre Salado, Carlos Arturo.
Se presenta la metodología y los resultados obtenidos sobre estimación de almacenamiento de carbono mediante técnicas de percepción remota en bosques manejados de Pinus patula en Zacualtipán, Hidalgo, México; la cual surge como una necesidad de monitoreo de los recursos forestales a partir de los compromisos adquiridos por México en el Protocolo de Kyoto para aminorar el inminente cambio climático causado por los denominados gases invernadero (CO2). En esta tesis se estudia principalmente el carbono (CHA) (Mg/ha) aunque preliminarmente resulta necesaria la cuantificación de biomasa (BHA) (Mg/ha). De manera paralela también se estudian algunos parámetros forestales de densidad como índice de área foliar (IAF) (m2/ m2), cobertura arbórea (COB) (%), área...
Palavras-chave: Carbono; Índice de área foliar; Cobertura arbórea; Regresión lineal; K-nn; Percepción remota; SPOT 5; Fotografía hemisferica; Bosque de Pinus patula. Carbon; Leaf area index; Canopy closure; Linear regression; K-nn; Remote sensing; SPOT 5; Hemispherical photography; Pinus patula forest..
Ano: 2012 URL: http://hdl.handle.net/10521/849
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Almacenamiento de carbono en bosques manejados de pinus patula: Estimación mediante percepción remota Colegio de Postgraduados
Aguirre Salado, Carlos Arturo.
Se presenta la metodología y los resultados obtenidos sobre estimación de almacenamiento de carbono mediante técnicas de percepción remota en bosques manejados de Pinus patula en Zacualtipán, Hidalgo, México; la cual surge como una necesidad de monitoreo de los recursos forestales a partir de los compromisos adquiridos por México en el Protocolo de Kyoto para aminorar el inminente cambio climático causado por los denominados gases invernadero (CO2). En esta tesis se estudia principalmente el carbono (CHA) (Mg/ha) aunque preliminarmente resulta necesaria la cuantificación de biomasa (BHA) (Mg/ha). De manera paralela también se estudian algunos parámetros forestales de densidad como índice de área foliar (IAF) (m2/ m2), cobertura arbórea (COB) (%), área...
Palavras-chave: Carbono; Índice de área foliar; Cobertura arbórea; Regresión lineal; K-nn; Percepción remota; SPOT 5; Fotografía hemisferica; Bosque de Pinus patula. Carbon; Leaf area index; Canopy closure; Linear regression; K-nn; Remote sensing; SPOT 5; Hemispherical photography; Pinus patula forest..
Ano: 2012 URL: http://hdl.handle.net/10521/789
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Almacenamiento de carbono en bosques manejados de pinus patula: Estimación mediante percepción remota Colegio de Postgraduados
Aguirre Salado, Carlos Arturo.
Se presenta la metodología y los resultados obtenidos sobre estimación de almacenamiento de carbono mediante técnicas de percepción remota en bosques manejados de Pinus patula en Zacualtipán, Hidalgo, México; la cual surge como una necesidad de monitoreo de los recursos forestales a partir de los compromisos adquiridos por México en el Protocolo de Kyoto para aminorar el inminente cambio climático causado por los denominados gases invernadero (CO2). En esta tesis se estudia principalmente el carbono (CHA) (Mg/ha) aunque preliminarmente resulta necesaria la cuantificación de biomasa (BHA) (Mg/ha). De manera paralela también se estudian algunos parámetros forestales de densidad como índice de área foliar (IAF) (m2/ m2), cobertura arbórea (COB) (%), área...
Tipo: Tesis Palavras-chave: Carbono; Índice de área foliar; Cobertura arbórea; Regresión lineal; K-nn; Percepción remota; SPOT 5; Fotografía hemisferica; Bosque de Pinus patula.; Carbon; Leaf area index; Canopy closure; Linear regression; K-nn; Remote sensing; SPOT 5; Hemispherical photography; Pinus patula forest..
Ano: 2007 URL: http://hdl.handle.net/10521/1172
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Evaluación cuantitativa de diez variedades de alfalfa (Medicago sativa L.). Colegio de Postgraduados
Álvarez Vázquez, Perpetuo.
En México, la alfalfa es la leguminosa más utilizada en la alimentación del ganado lechero, debido a su alto rendimiento y valor nutritivo. El objetivo del presente estudio fue evaluar las variables que determinan el crecimiento y rendimiento de diez variedades de alfalfa a intervalos de corte definidos estacionalmente. El estudio se realizó de septiembre de 2011 a septiembre de 2012 en el Colegio de Postgraduados, Campus Montecillo, Texcoco, México. Las variedades de alfalfa estudiadas fueron: Vía Láctea, Chipilo, Atlixco, Oaxaca, San Miguelito, Cuf-101, Milenia, Aragón, Valenciana y Júpiter, distribuidas aleatoriamente en un diseño experimental completamente al azar con cuatro repeticiones. El mayor rendimiento (14,510 kg MS ha-1), tasa de crecimiento...
Palavras-chave: Medicago sativa L.; Rendimiento; Radiación interceptada; Indice de área foliar; Densidad de plantas; Herbage yield; Intercepted radiation; Leaf area index; Plant density; Ganadería; Maestría.
Ano: 2013 URL: http://hdl.handle.net/10521/2031
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Using Remote Sensing and Geographic Information Systems to Study Urban Quality of Life and Urban Forest Amenities Ecology and Society
Jensen, Ryan; Indiana State University; r-jensen@indstate.edu; Gatrell, Jay; ;; Boulton, Jim; ;; Harper, Bruce; ;.
This study examines urban quality of life by assessing the relationship between observed socioeconomic conditions and urban forest amenities in Terre Haute, Indiana, USA. Using remote-sensing methods and techniques, and ordinary least squares regression, the paper determines the relationship between urban leaf area and a population density parameter with median income and median housing value. Results demonstrate positive correlations between urban leaf area, population density, and their interaction with median income and median housing value. Furthermore, leaf area, density, and their interaction statistically account for observed variance in median income and median housing value, indicating that these variables may be used to study observed...
Tipo: Peer-Reviewed Reports Palavras-chave: Leaf area index; Remote sensing; Urban forestry; Urban quality of life.
Ano: 2005
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Influence of data acquisition geometry on soybean spectral response simulated by the prosail model REA
Breunig,Fábio M.; Galvão,Lênio S.; Formaggio,Antonio R.; Epiphanio,José C. N..
View angle and directional effects significantly affect reflectance and vegetation indices, especially when daily images collected by large field-of-view (FOV) sensors like the Moderate Resolution Imaging Spectroradiometer (MODIS) are used. In this study, the PROSAIL radiative transfer model was chosen to evaluate the impact of the geometry of data acquisition on soybean reflectance and two vegetation indices (Normalized Difference Vegetation Index - NDVI and Enhanced Vegetation Index -EVI) by varying biochemical and biophysical parameters of the crop. Input values for PROSAIL simulation were based on the literature and were adjusted by the comparison between simulated and real satellite soybean spectra acquired by the MODIS/Terra and hyperspectral...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Leaf area index; NDVI; EVI; Reflectance; MODIS; Remote sensing.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000100018
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A new method for estimating the leaf area index of cucumber and tomato plants Horticultura Brasileira
Blanco,Flávio Favaro; Folegatti,Marcos Vinícius.
Non-destructive methods of leaf area measurement are useful for small plant populations, such as experiments with potted plants, and allow the measurement of the same plant several times during the growing period. A methodology was developed to estimate the leaf area index (LAI) of cucumber and tomato plants through the evaluation of the leaf area distribution pattern (LADP) of the plants and the relative height of the leaves in the plants. Plant and leaf height, as well as the length and width of all leaves were measured and the area of some leaves was determined by a digital area meter. The obtained regression equations were used to estimate the leaf area for all relative heights along the plant. The LADP adjusted to a quadratic model for both crops and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cucumis sativus L.; Esculentum Mill.; Greenhouse; Leaf area index.
Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362003000400019
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Interceptação da radiação fotossinteticamente ativa em milho verão solteiro e consorciado com braquiária sob diferentes arranjos de plantas. Infoteca-e
MAKINO, P. A.; SANTOS, A. L. F. dos; RIBEIRO, L. M.; COSTA, I. M. da; NARDI, J. W.; CECCON, G..
Tipo: Resumo em anais e proceedings Palavras-chave: Índice de área foliar; Interceptação luminosa; Densidade de plantas; Light interception; Leaf area index; Plant density.
Ano: 2016 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1054309
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Effect of dates of planting, plant geometry and number of seedlings on growth and yield of hybrid rice (Oryza sativa L.) Open Agri
V.K..
Palavras-chave: Hybrids; Grain; Heterosis; Planting date; Dry matter; Spacing; Yields; Field experimentation; Plant population; Leaf area index.
Ano: 2008 URL: http://agropedia.iitk.ac.in/openaccess/?q=node/4676
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Solar radiation use efficiency by soybean under field conditions in the Amazon region PAB
Souza,Paulo Jorge de Oliveira Ponte de; Ribeiro,Aristides; Rocha,Edson José Paulino da; Farias,José Renato Bouça; Loureiro,Renata Silva; Bispo,Carlos Capela; Sampaio,Leila.
The objective of this work was to evaluate the efficiency of soybean (Glycine max) in intercepting and using solar radiation under natural field conditions, in the Amazon region, Brazil. The meteorological data and the values of soybean growth and leaf area were obtained from an agrometeorological experiment carried out in Paragominas, Pará state, during 2007 and 2008. The radiation use efficiency (RUE) was obtained from the ratio between the above-ground biomass production and the intercepted photosynthetically active radiation (PAR) accumulated to 99 and 95 days after sowing, in 2007 and 2008, respectively. Climatic conditions during the experiment were very distinct, with reduction in rainfall in 2007, which began during the soybean mid-cycle, due to...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Glycine max; Amazon region; Leaf area index; Radiation interception.
Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2009001000001
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Heliotropic responses of soybean cultivars at three phenological stages and under two water regimes PAB
Rakocevic,Miroslava; Neumaier,Norman; Oliveira,Gustavo Migliorini de; Nepomuceno,Alexandre Lima; Farias,José Renato Bouças.
The objectives of this work were to determine the heliotropic movements of the upper trifoliates for two soybean cultivars, BR 16 and Embrapa 48, during a daily cycle, in three phenological stages and two water regimes, and to estimate the impact of irrigation and daily leaflet movements on agronomic characteristics and grain yield. Heliotropic movements were studied in three phenological stages: V4-V6, V7-V10, and R5 in irrigated and non-irrigated plots. For each stage, the leaflet elevation and azimuth were measured hourly. Under a low (V4-V6 stage) and mid (V7-V10 stage) leaf area index (LAI) the diaheliotropism was slightly more frequent and intensive in non-irrigated than in irrigated plants, only at early morning and late afternoon hours. At R5 stage...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Glycine max; Diaheliotropism; Irrigation; Leaf area index; Paraheliotropism.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2010000700005
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Tiller size/density compensation in grazed Tifton 85 bermudagrass swards PAB
Sbrissia,André Fischer; Silva,Sila Carneiro da; Matthew,Cory; Carvalho,Carlos Augusto Brandão de; Carnevalli,Roberta Aparecida; Pinto,Luiz Felipe de Moura; Fagundes,Jaílson Lara; Pedreira,Carlos Guilherme Silveira.
The objective of this study was to evaluate the occurrence of the tiller size/density compensation mechanism in Tifton 85 bermudagrass swards grazed by sheep under continuous stocking. Treatments corresponded to four sward steady state conditions (5, 10, 15, and 20 cm of sward surface height), maintained by sheep grazing. The experimental design was a complete randomized block with four replicates. Pasture responses evaluated include: tiller population density, tiller mass, leaf mass and leaf area per tiller, and herbage mass. Tiller volume, leaf area index, tiller leaf/stem ratio, and tiller leaf area/volume ratio were calculated and simple regression analyses between tiller population density and tiller mass were performed. Measurements were made in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cynodon; Leaf area index; Mass; Density; Plant morphology.
Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2003001200013
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Simulation of soybean growth and yield under northeastern Amazon climatic conditions PAB
Souza,Paulo Jorge de Oliveira Ponte de; Farias,José Renato Bouças; Abreu,José Paulo Mourão de Melo e; Ribeiro,Aristides; Rocha,Edson José Paulino da; Botelho,Marcel do Nascimento; Sousa,Adriano Marlisom Leão de.
The objective of this work was to parameterize, calibrate, and validate a new version of the soybean growth and yield model developed by Sinclair, under natural field conditions in northeastern Amazon. The meteorological data and the values of soybean growth and leaf area were obtained from an agrometeorological experiment carried out in Paragominas, PA, Brazil, from 2006 to 2009. The climatic conditions during the experiment were very distinct, with a slight reduction in rainfall in 2007, due to the El Niño phenomenon. There was a reduction in the leaf area index (LAI) and in biomass production during this year, which was reproduced by the model. The simulation of the LAI had root mean square error (RMSE) of 0.55 to 0.82 m² m-2, from 2006 to 2009. The...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Glycine max; Amazon region; Climate models; Leaf area index; Soybean crop expansion; Yield simulation.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2011000600001
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Impact of Nitrogen Levels on Associated Weeds, Fodder Ability and Grain Protein Content of Dual-Purpose Wheat Planta Daninha
NAVEED,K.; BALOCH,M.S.; QAYYUM,A.; MEHMOOD,A.; HUSSAIN,I.; ALI,N..
ABSTRACT: Studies were carried out to see the response of dual-purpose wheat to different nitrogen levels i.e. 0, 50, 100, 150 and 200 kg N ha-1 in cut (for forage and grain purpose) vs. uncut (for grain only) treatments at the Agriculture Research Institute, Dera Ismail Khan, Pakistan during the years 2009-10 and 2010-11. The results revealed that maximum number of days to heading (123.5 and 124.5), plant height (117.7 and 116.6 cm), grain protein content (11.59 and 12.47%), fresh forage yield (2,646 and 2,956 kg ha-1) and grain yield (4,631 and 4,489 kg ha-1) were recorded in plots that received either 150 or 200 kg ha-1 nitrogen respectively and vice-versa. The data indicated higher values for number of days to heading in cut (124.9) as compared to...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Crop growth rate; Leaf area index; Nitrogen levels; Crop production.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100309
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Biometric Responses of Soybean to Different Potassium Fertilization Management Practices in Years with High and Low Precipitation Rev. Bras. Ciênc. Solo
Esper Neto,Michel; Minato,Evandro Antonio; Besen,Marcos Renan; Inoue,Tadeu Takeyoshi; Batista,Marcelo Augusto.
ABSTRACT Brazilian soybean producers commonly apply maintenance potassium (K) fertilization during cultivation to restore the K taken up by plants; however, this measure can modify the morphophysiological plant characteristics, since the functions of K are closely related with plant growth and development. This study assessed the morphological changes in soybean plants in response to K rates, sowing fertilization, and the application periods of K fertilization in a Latossolo Vermelho eutroférrico (Oxisol) under a no-tillage system, located in the municipality of Floresta, Paraná. A randomized block design was used in the experiment with four replications in a fully crossed factorial design (5 × 2 × 2). The experiment was carried out in two growing seasons...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Leaf area index; Correlation; Yield; Drought.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100525
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Environmental control on water vapour and energy exchanges over grasslands in semiarid region of Brazil AGRIAMBI
Gondim,Patrícia S. de S.; Lima,José R. de S.; Antonino,Antonio C. D.; Hammecker,Claude; Silva,Renan A. B. da; Gomes,Clarissa A..
A micrometeorological experiment was conducted over grasslands in a semi-arid region of north-eastern Brazil (São João, Pernambuco) from January to December 2011, using the Bowen ratio energy balance method, to improve the current understanding of energy partitioning and water vapour exchange over this ecosystem in this region. The objectives of the present study were to quantify the seasonal and diurnal variations in energy and water vapour exchanges over grasslands and understand the biotic and abiotic factors controlling the energy partitioning of this ecosystem. In the dry period, the low stored soil water limited the grass production and leaf area index, and as a consequence of these conditions, most of the annual net radiation (58%) was consumed in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Evapotranspiration; Soil water content; Leaf area index.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662015000100003
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Hemispherical photography to estimate biophysical variables of cotton AGRIAMBI
Brandão,Ziany N.; Zonta,João H..
ABSTRACT The Leaf Area Index (LAI) is a key parameter to evaluate the vegetation spectral response, estimating plant nutrition and water requirements. However, in large fields is difficult to obtain accurate data to LAI determination. Therefore, the objective of this study was the estimation of LAI, biomass and yield of irrigated cotton through digital hemispherical photography. The treatments consisted of four nitrogen doses (0, 90, 180 and 270 kg ha-1) and four phosphorus doses (0, 120, 240 and 360 kg ha-1). Digital hemispherical photographs were collected under similar sky brightness conditions at 60 and 75 days after emergence (DAE), performed by the Digital Plant Canopy Imager - CI-110® of CID Inc. Biomass and LAI measurements were made on the same...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Leaf area index; Cotton biomass; Plant Canopy Imager CI-110.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000900789
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