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Land cover-based optimal deconvolution of PALS L-band microwave brightness temperatures / A.S. Limaye in Remote sensing of environment, vol 92 n° 4 (30 September 2004)
[article]
Titre : Land cover-based optimal deconvolution of PALS L-band microwave brightness temperatures Type de document : Article/Communication Auteurs : A.S. Limaye, Auteur ; William L. Crosson, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 497 - 506 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] agriculture
[Termes IGN] biomasse
[Termes IGN] capteur actif
[Termes IGN] capteur passif
[Termes IGN] déconvolution
[Termes IGN] Glycine max
[Termes IGN] Iowa (Etats-Unis)
[Termes IGN] luminance lumineuse
[Termes IGN] maïs (céréale)
[Termes IGN] Passive and Active L and S band Sensor
[Termes IGN] Soil Moisture Experiment
[Termes IGN] température de luminanceRésumé : (Auteur) An optimal deconvolution (ODC) technique has been developed to estimate microwave brightness temperatures of agricultural fields using microwave radiometer observations. The technique is applied to airborne measurements taken by the Passive and Active L and S band (PALS) sensor in Iowa during Soil Moisture Experiments in 2002 (SMEX02). Agricultural fields in the study area were predominantly soybeans and corn. The brightness temperatures of corn and soybeans were observed to be significantly different because of large differences in vegetation biomass. PALS observations have significant over-sampling; observations were made about 100 m apart and the sensor footprint extends to about 400 m. Conventionally, observations of this type are averaged to produce smooth spatial data fields of brightness temperatures. However, the conventional approach is in contrast to reality in which the brightness temperatures are in fact strongly dependent on land cover, which is characterized by sharp boundaries. In this study, we mathematically deconvolve the observations into brightness temperature at the field scale (500-800 m) using the sensor antenna response function. The result is more accurate spatial representation of field-scale brightness temperatures, which may in turn lead to more accurate soil moisture retrieval. Numéro de notice : A2004-415 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2004.02.019 En ligne : https://doi.org/10.1016/j.rse.2004.02.019 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26942
in Remote sensing of environment > vol 92 n° 4 (30 September 2004) . - pp 497 - 506[article]Retrieval of soil moisture from passive and active L/S band sensor (PALS) observations during the soil moisture experiment in 2002 (SMEX) / U. Narayan in Remote sensing of environment, vol 92 n° 4 (30 September 2004)
[article]
Titre : Retrieval of soil moisture from passive and active L/S band sensor (PALS) observations during the soil moisture experiment in 2002 (SMEX) Type de document : Article/Communication Auteurs : U. Narayan, Auteur ; V. Lakshmi, Auteur ; E. Njoku, Auteur Année de publication : 2004 Article en page(s) : pp 483 - 496 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bande L
[Termes IGN] bande S
[Termes IGN] bande spectrale
[Termes IGN] capteur actif
[Termes IGN] capteur passif
[Termes IGN] Glycine max
[Termes IGN] humidité du sol
[Termes IGN] Iowa (Etats-Unis)
[Termes IGN] maïs (céréale)
[Termes IGN] Passive and Active L and S band Sensor
[Termes IGN] régression
[Termes IGN] Soil Moisture Experiment
[Termes IGN] teneur en eau de la végétation
[Termes IGN] transfert radiatifRésumé : (Auteur) The Soil Moisture Experiments in 2002 (SMEX02) were conducted in Iowa between June 25th and July 12th, 2002. A major aim of the experiments was examination of existing algorithms for soil moisture retrieval from active and passive microwave remote sensors under high vegetation water content conditions. The data obtained from the passive and active L and S band sensor (PALS) along with physical variables measured by in situ sampling have been used in this study to demonstrate the sensitivity of the instrument to soil moisture and perform soil moisture retrieval using statistical regression and physical modeling techniques. The land cover conditions in the region studied were predominantly soybean and corn crops with average vegetation water contents ranging from 0 to ~ 5 kg/m2. The PALS microwave sensitivity to soil moisture under these vegetation conditions was investigated for both passive and active measurements. The performance of the PALS instrument and retrieval algorithms has been analyzed, indicating soil moisture retrieval errors of approximately 0.04 g/g gravimetric soil moisture. Statistical regression techniques have been shown to perform satisfactorily with soil moisture retrieval error of around 0.05 g/g gravimetric soil moisture. The retrieval errors were higher for the corn than for the soybean fields due to the higher vegetation water content of the corn crops. However, the algorithms performed satisfactorily over the full range of vegetation conditions. Numéro de notice : A2004-414 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2004.05.018 En ligne : https://doi.org/10.1016/j.rse.2004.05.018 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26941
in Remote sensing of environment > vol 92 n° 4 (30 September 2004) . - pp 483 - 496[article]Monitoring surface soil moisture in post-harvest rice areas using C-band radar imagery in NorthEast Thailand / S. Kaojarern in Geocarto international, vol 19 n° 3 (September - November 2004)
[article]
Titre : Monitoring surface soil moisture in post-harvest rice areas using C-band radar imagery in NorthEast Thailand Type de document : Article/Communication Auteurs : S. Kaojarern, Auteur ; Thuy Le Toan, Auteur ; M.W. Davidson, Auteur Année de publication : 2004 Article en page(s) : pp 61 - 71 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] agriculture
[Termes IGN] bande C
[Termes IGN] humidité du sol
[Termes IGN] image ERS-SAR
[Termes IGN] image radar
[Termes IGN] image Radarsat
[Termes IGN] rizière
[Termes IGN] seuillage d'image
[Termes IGN] surveillance agricole
[Termes IGN] surveillance météorologique
[Termes IGN] ThaïlandeRésumé : (Auteur) The objective of this study is to estimate the residual surface soil moisture of rice fields after harvesting, in Northeast Thailand, using Cband SAR images. Such information is use 1 to determine possibilities of cultivating additional shortcycle crops after the harvesting of the main rice crop. To accomplish this objective this study exploits three Cband SAR images acquired over the test area along with simultaneous ground measurements collected in support of analysis of the SAR images. The main parameters measured on the ground were: the volumetric moisture content of the soil using time domain reflectrometry (TDR), the surface roughness, using profile data, and residue cover. Other field environmental factors that might affect radar backscattering, including the topography of rice terraces (elevation, slope, and aspect), bund height between rice fields, soil types, and density of sparse tree stands were also acquired and registered to the image data. Before the analysis, the SAR images were calibrated, registered, and then filtered using multitemporal and spatial filters to reduce variability of the radar backscattering coefficient due to speckle. The measured soil moisture values were then correlated with the radar backscattering coefficients of the experimental plots and the results interpreted in terms of the main environmental factors. Varying residue cover and field aspect angles were found to significantly affect the relationship between radar backscatter and soil moisture content and therefore had to be taken into account before inverting the image data into soil moisture maps. Overall it was found that two soil moisture classes could reliably be separated using the SAR images, and that soil moisture maps could be obtained through a simple inversion technique based on applying a threshold to the SAR images. Analyses of these resulting moisture maps indicate that SAR data is useful to monitor and map surface soil moisture in rice fields after harvest. Numéro de notice : A2004-479 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106040408542319 Date de publication en ligne : 02/01/2008 En ligne : https://doi.org/10.1080/10106040408542319 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26997
in Geocarto international > vol 19 n° 3 (September - November 2004) . - pp 61 - 71[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-04031 RAB Revue Centre de documentation En réserve L003 Disponible Spatial variability in classification accuracy of agricultural crops in the Dutch national land-cover database / A.J.W. Van Oort in International journal of geographical information science IJGIS, vol 18 n° 6 (october 2004)
[article]
Titre : Spatial variability in classification accuracy of agricultural crops in the Dutch national land-cover database Type de document : Article/Communication Auteurs : A.J.W. Van Oort, Auteur ; Arnold K. Bregt, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 611 - 626 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie numérique
[Termes IGN] base de données d'occupation du sol
[Termes IGN] base de données localisées
[Termes IGN] classe d'objets
[Termes IGN] cultures
[Termes IGN] données maillées
[Termes IGN] occupation du sol
[Termes IGN] Pays-Bas
[Termes IGN] paysage
[Termes IGN] pixel
[Termes IGN] précision de la classificationRésumé : (Auteur) Variability in per cell classification accuracy is predominantly modelled with landcover class as the explanatory variable, i.e. with users' accuracies from the error matrix. Logistic regression models were developed to include other explanatory variables: heterogeneity in the 3 x 3 window around a cell, the size of the patch and the complexity of the landscape in which a cell is located. It was found that per cell, the probability of correct classification was significantly (a = 0.05) higher for cells with a less heterogeneous neighbourhood, for cells part of larger patches and for cells in regions with a less heterogeneous landscape. To validate the models, a leave-one-out procedure was applied in which the absolute difference between the actual and the model-estimated number of cells correctly classified was summarized over 55 regions in the Netherlands. The sum of differences reduced from 60.9 to 48.1 after adding the variables 'patch size' and 'landscape dominance' to the land-cover class model. Spatial variability thus modelled therefore led to a substantial improvement in the estimation of the per cell classification accuracy. Numéro de notice : A2004-353 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810410001701969 En ligne : https://doi.org/10.1080/13658810410001701969 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26880
in International journal of geographical information science IJGIS > vol 18 n° 6 (october 2004) . - pp 611 - 626[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-04061 RAB Revue Centre de documentation En réserve L003 Disponible 079-04062 RAB Revue Centre de documentation En réserve L003 Disponible Use of hyperspectral derivative ratios in the red-edge region to identify plant stress responses to gas leaks / K.L. Smith in Remote sensing of environment, vol 92 n° 2 (15/08/2004)
[article]
Titre : Use of hyperspectral derivative ratios in the red-edge region to identify plant stress responses to gas leaks Type de document : Article/Communication Auteurs : K.L. Smith, Auteur ; M.D. Steven, Auteur ; J.J. Colls, Auteur Année de publication : 2004 Article en page(s) : pp 207 - 217 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bande visible
[Termes IGN] blé (céréale)
[Termes IGN] canalisation
[Termes IGN] feuille (végétation)
[Termes IGN] gaz
[Termes IGN] herbe
[Termes IGN] image hyperspectrale
[Termes IGN] oxygène (O²)
[Termes IGN] pollution
[Termes IGN] rayonnement proche infrarouge
[Termes IGN] réflectance végétale
[Termes IGN] végétationRésumé : (Auteur) Hyperspectral features in the red-edge region were tested as an index of plant stress responses to soil -oxygen depletion. The aim was to provide the basis for a warning system to identify natural gas leakage by the spectral responses of plants growing in the affected soil.
Elevated concentrations of natural gas in the soil atmosphere were used to deplete oxygen concentrations around the roots of grass, wheat (Hordeum vulgare cv Claire) and bean (Vicia faba cv Clipper) growing in a field facility. Visible symptoms due to the natural gas included reduced growth of the plants and chlorosis of the leaves.
Spectral responses included increased reflectance in the visible wavelengths and decreased reflectance in the near infra-red. Derivative analysis identified features within the red-edge at 720-730 and 702 nm. Ratios of the magnitude of the derivative at 725 to that at 702 nm were less in areas where gas was present. This ratio enabled identification of stress due to gas leakage up to 7 days before visible symptoms were observed and also at the edges of gassed plots where visible symptoms were not expressed. The technique was able to identify stress responses to long-term leaks in all the crops tested but to short-term leaks only in grass. This study therefore suggests that under appropriate conditions remote sensing could be used to detect pipeline gas leaks from decreases in the ratio of peaks within the red-edge.Numéro de notice : A2004-334 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2004.06.002 En ligne : https://doi.org/10.1016/j.rse.2004.06.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26861
in Remote sensing of environment > vol 92 n° 2 (15/08/2004) . - pp 207 - 217[article]Evaporing estimation in the Yellow River basin, China using integrated NDVI data / R. Sun in International Journal of Remote Sensing IJRS, vol 25 n° 13 (July 2004)PermalinkUsing Thematic Mapper data for change detection and sustainable use of cultivated land: a case study in the Yellow River delta, China / G.X. Zhao in International Journal of Remote Sensing IJRS, vol 25 n° 13 (July 2004)PermalinkPotential of using NOAA-AVHRR data for estimating irrigated area to help solve an inter-state water dispute / V.K. Boken in International Journal of Remote Sensing IJRS, vol 25 n° 12 (June 2004)PermalinkAssessing the effects of human-induced land degradation in the former homelands of northern South Africa with a 1 km AVHRR NDVI time-series / K.J. Wessels in Remote sensing of environment, vol 91 n° 1 (15/05/2004)PermalinkClassification of contamination in salt marsh plant using hyperspectral reflectance / M.D. Wilson in IEEE Transactions on geoscience and remote sensing, vol 42 n° 5 (May 2004)PermalinkHyperspectral vegetation indices and novel algorithms for predicting green LAI of crop canopies: modelling and validation in the context of precision agriculture / D. Haboudane in Remote sensing of environment, vol 90 n° 3 (15/04/2004)PermalinkAirborne measurement of hot spot reflectance signatures / F. Camacho-De Coca in Remote sensing of environment, vol 90 n° 1 (15/03/2004)PermalinkDynamique de la déforestation et agriculture pionnière dans le sud-ouest de Madagascar : exploitation diachronique de l'imagerie satellitale haute résolution / F. Lasry in Photo interprétation, vol 40 n° 1 (Mars 2004)PermalinkInvestigation into small-format camera sensors for level development of USDA GIS of crop compliance / S.D. Lyle in Surveying and land information science, vol 64 n° 1 (01/03/2004)PermalinkThe consequences of urban transformation on net primary productivity in the United States / M.L. Imhoff in Remote sensing of environment, vol 89 n° 4 (29/02/2004)Permalink