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Comparisons of land cover and LAI estimates derived from ETM+ and MODIS for four sites in North America: a quality assessment of 2000/2001 provisional MODIS / W.B. Cohen in Remote sensing of environment, vol 88 n° 3 (15/12/2003)
[article]
Titre : Comparisons of land cover and LAI estimates derived from ETM+ and MODIS for four sites in North America: a quality assessment of 2000/2001 provisional MODIS Type de document : Article/Communication Auteurs : W.B. Cohen, Auteur ; T.K. Maiersperger, Auteur ; S.T. Gower, Auteur ; S.W. Running, Auteur ; et al., Auteur Année de publication : 2003 Article en page(s) : pp 233 - 255 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Advanced Very High Resolution Radiometer
[Termes IGN] agriculture
[Termes IGN] analyse comparative
[Termes IGN] forêt
[Termes IGN] image Landsat-ETM+
[Termes IGN] Leaf Area Index
[Termes IGN] Moderate Resolution Imaging Spectroradiometer
[Termes IGN] occupation du solRésumé : (Auteur) The MODIS land science team produces a number of standard products, including land cover and leaf area index (LAI). Critical to the success of MODIS and other sensor products is an independent evaluation of product quality. In that context, we describe a study using field data and Landsat ETM+ to map land cover and LAI at four 49-km2 sites in North America containing agricultural cropland (AGRO), prairie grassland (KONZ), boreal needleleaf forest, and temperate mixed forest. The purpose was to: (1) develop accurate maps of land cover, based on the MODIS IGBP (International Geosphere-Biosphere Programme) land cover classification scheme; (2) derive continuous surfaces of LAI that capture the mean and variability of the LAI field measurements; and (3) conduct initial MODIS validation exercises to assess the quality of early (i.e., provisional) MODIS products. ETM+ land cover maps varied in overall accuracy from 81% to 95%. The boreal forest was the most spatially complex, had the greatest number of classes, and the lowest accuracy. The intensive agricultural cropland had the simplest spatial structure, the least number of classes, and the highest overall accuracy. At each site, mapped LAI patterns generally followed patterns of land cover across the site. Predicted versus observed LAI indicated a high degree of correspondence between field-based measures and ETM+ predictions of LAI. Direct comparisons of ETM+ land cover maps with Collection 3 MODIS cover maps revealed several important distinctions and similarities. One obvious difference was associated with image/map resolution. ETM+ captured much of the spatial complexity of land cover at the sites. In contrast, the relatively coarse resolution of MODIS did not allow for that level of spatial detail. Over the extent of all sites, the greatest difference was an overprediction by MODIS of evergreen needleleaf forest cover at the boreal forest site, which consisted largely of open shrubland, woody savanna, and savanna. At the agricultural, temperate mixed forest, and prairie grassland sites, ETM+ and MODIS cover estimates were similar. Collection 3 MODISbased LAI estimates were considerably higher (up to 4m2 4m-2) than those based on ETM+ LAI at each site. There are numerous probable reasons for this, the most important being the algorithms' sensitivity to MODIS reflectance calibration, its use of a prelaunch AVHRR-based land cover map, and its apparent reliance on mainly red and near-IR reflectance. Samples of Collection 4 LAI products were examined and found to consist of significantly improved LAI predictions for KONZ, and to some extent for AGRO, but not for the other two sites. In this study, we demonstrate that MODIS reflectance data are highly correlated with LAI across three study sites, with relationships increasing in strength from 500 to 1000 m spatial resolution, when shortwave-infrared bands are included. Numéro de notice : A2003-345 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.06.006 En ligne : https://doi.org/10.1016/j.rse.2003.06.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26425
in Remote sensing of environment > vol 88 n° 3 (15/12/2003) . - pp 233 - 255[article]Geographical weighting as a further refinement to regression modelling: an example focused on the NDVI-rainfall relationship / Giles M. Foody in Remote sensing of environment, vol 88 n° 3 (15/12/2003)
[article]
Titre : Geographical weighting as a further refinement to regression modelling: an example focused on the NDVI-rainfall relationship Type de document : Article/Communication Auteurs : Giles M. Foody, Auteur Année de publication : 2003 Article en page(s) : pp 283 - 293 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] méthode des moindres carrés
[Termes IGN] modèle de régression
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] précipitationRésumé : (Auteur) The regression analyses undertaken commonly in remote sensing are aspatial, ignoring the locational information associated with each sample site at which the variables under study were measured. Typically, basic ordinary least squares regression analysis is used to derive a relationship that is believed to be uniformly applicable across the study area. Although such global analyses may appear satisfactory, often with large coefficients of determination derived, they may provide an inappropriate description of the relationship between the variables under study. In particular, a global regression analysis may miss local detail that can be significant if the relationship is spatially nonstationary. Local statistical approaches, such as geographically weighted regression, include the spatial coordinates of the sample sites in the analysis and may provide a more appropriate basis for the investigation of the relationship between variables. The potential value of geographically weighted regression to the remote sensing community is illustrated with reference to the relationship between the normalised difference vegetation index (NDVI) and rainfall over north Africa and the Middle East over an 8-year period. For each year, spatial non-stationarity was evident, particularly with regard to the slope parameter of the regression model. Moreover, the conventional ordinary least squares regression models, while superficially strong (minimum R2 == 0.67), were relatively poor local descriptors of the relationship. Relative to this, the geographically weighted approach to regression provided considerably stronger relationships from the same data sets (minimum R2 = 0.96) as well as highlighting areas of local variation. The implications of the difference in the outputs from the two types of regression analysis are illustrated with reference to the use of the derived NDVI-rainfall relationships in mapping desert extent. For example, with the data relating to 1987 the southern limit of the Sahara was generally estimated to lie at a more southerly position when the relationship derived from OLS rather than geographically weighted regression was used. Numéro de notice : A2003-346 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.08.004 En ligne : https://doi.org/10.1016/j.rse.2003.08.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26426
in Remote sensing of environment > vol 88 n° 3 (15/12/2003) . - pp 283 - 293[article]Training a neural network with a canopy reflectance model to estimate crop leaf area index / F. Mark Danson in International Journal of Remote Sensing IJRS, vol 24 n° 23 (December 2003)
[article]
Titre : Training a neural network with a canopy reflectance model to estimate crop leaf area index Type de document : Article/Communication Auteurs : F. Mark Danson, Auteur ; C.S. Rowland, Auteur Année de publication : 2003 Article en page(s) : pp 4891 - 4905 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] betterave sucrière
[Termes IGN] classification par réseau neuronal
[Termes IGN] indice de végétation
[Termes IGN] Leaf Area Index
[Termes IGN] neurone artificiel
[Termes IGN] réflectance végétaleRésumé : (Auteur) This paper outlines the strategies available for estimating the biophysical properties of crop canopies from remotely sensed data. Spectral reflectance and biophysical data were obtained over 132 plots of sugar beet (Beta vulgaris L.) and in the first part of the paper the strength of the relationships between vegetation indices (VI) and leaf area index (LAI) are examined. In the second part, an approach is tested in which a canopy reflectance model is used to generate simulated spectra for a wide range of biophysical conditions and these data are used to train an artificial neural network (ANN). The advantage of the second approach is that a priori knowledge of the measurement conditions including soil reflectance, canopy architecture and solar position can be included explicitly in the modelling. The results show that the estimation of sugar beet LAI using a trained neural network is more reliable than the use of VI and has the potential to replace the use of VI for operational applications. The use of a priori data on the variation in soil spectral reflectance gave rise to a small increase in LAI estimation accuracy. Numéro de notice : A2003-315 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000070319 En ligne : https://doi.org/10.1080/0143116031000070319 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22611
in International Journal of Remote Sensing IJRS > vol 24 n° 23 (December 2003) . - pp 4891 - 4905[article]Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 080-03231 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Usefulness of spectral reflectance indices as durum wheat yield predictors under contrasting Mediterranean conditions / C. Royo in International Journal of Remote Sensing IJRS, vol 24 n° 22 (November 2003)
[article]
Titre : Usefulness of spectral reflectance indices as durum wheat yield predictors under contrasting Mediterranean conditions Type de document : Article/Communication Auteurs : C. Royo, Auteur ; N. Aparicio, Auteur ; D. Villegas, Auteur ; J. Casadesus, Auteur ; P. Monneveux, Auteur ; J.L. Araus, Auteur Année de publication : 2003 Article en page(s) : pp 4403 - 4419 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] blé (céréale)
[Termes IGN] couvert végétal
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] réflectance spectrale
[Termes IGN] réflectance végétale
[Termes IGN] rendement agricoleRésumé : (Auteur) Early prediction of crop yield can be an important tool for identifying promising genotypes in breeding programmes. To assess whether measurements of canopy reflectance at given stages of development could be used for yield forecasting and to identify the most appropriate indices, locations and growth stages for durum wheat yield assessment, nine field experiments, each including 20 or 25 durum wheat (Triticum turgidum L. var durum) genotypes, were carried out under a wide range of Mediterranean conditions. Canopy reflectance was recorded with a portable field spectroradiometer at several times from booting to physiological maturity. and nine indices were further derived. Grain yield15 was measured at harvesting. The results indicated that milkgrain stage was the most appropriate developmental stage for yield assessment. However, some indices were also sensitive to yield variations when determined at anthesis or even heading or booting. The capacity of spectral reflectance indices to forecast grain yield increased on locations that allowed genotypes to express their yield potentiality. Reflectance at 550 nm (R550), water index (WI), photochemical reflectance index (PRI). structural independent pigment index (SIPI), normalized difference vegetation index (NDVI) and simple ratio (SR) explained jointly a 95.7% of yield varlability when all the experiments were analysed together, 92% being explained by R550. When regression analyses were carried out separately for each experiment, spectral reflectance indices explained from 17.3% to 65.2% of total variation in yield. and the indices that best explained differences in yield were experimentdependent. Our data suggest that reflectance at 680 nm (R680), WI and SR may be suitable estimators of durum wheat grain yield under Mediterranean conditions, when determined at milkgrain stage. Numéro de notice : A2003-310 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000150059 En ligne : https://doi.org/10.1080/0143116031000150059 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22606
in International Journal of Remote Sensing IJRS > vol 24 n° 22 (November 2003) . - pp 4403 - 4419[article]Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 080-03221 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Land-use and land-cover change, urban heat island phenomenon, and health implications: a remote sensing approach / C.P. Lo in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 9 (September 2003)
[article]
Titre : Land-use and land-cover change, urban heat island phenomenon, and health implications: a remote sensing approach Type de document : Article/Communication Auteurs : C.P. Lo, Auteur ; D.A. Quattrochi, Auteur Année de publication : 2003 Article en page(s) : pp 1053 - 1063 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] Atlanta (Géorgie)
[Termes IGN] classification non dirigée
[Termes IGN] image Landsat-MSS
[Termes IGN] image Landsat-TM
[Termes IGN] milieu rural
[Termes IGN] milieu urbain
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] occupation du sol
[Termes IGN] ozone
[Termes IGN] pollution atmosphérique
[Termes IGN] risque sanitaire
[Termes IGN] santé
[Termes IGN] température de surface
[Termes IGN] utilisation du solNuméro de notice : A2003-235 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.69.9.1053 En ligne : https://doi.org/10.14358/PERS.69.9.1053 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22530
in Photogrammetric Engineering & Remote Sensing, PERS > vol 69 n° 9 (September 2003) . - pp 1053 - 1063[article]AVHRR-based spectral vegetation Index for quantitative assessment of vegetation state and productivity: calibration and validation / F. Kogan in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 8 (August 2003)PermalinkApplications and research using remote sensing for rangeland management / E.R. Hunt in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 6 (June 2003)PermalinkRemote sensing for crop management / P.J. Pinter in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 6 (June 2003)PermalinkSatellite multi-sensor data analysis of urban surface temperatures and Landcover / B. Dousset in ISPRS Journal of photogrammetry and remote sensing, vol 58 n° 1-2 (June - December 2003)PermalinkA comparative analysis of scanned maps and imagery for mapping applications / Costas Armenakis in ISPRS Journal of photogrammetry and remote sensing, vol 57 n° 5-6 (April - May 2003)PermalinkExpert system house detection in high spatial resolution: Imagery using size, shape, and context / J.A. Tullis in Geocarto international, vol 18 n° 1 (March - May 2003)PermalinkAssessment of the possible drought impact on farm production in the SE of the province of Buenos Aires, Argentina / T. Hartmann in ISPRS Journal of photogrammetry and remote sensing, vol 57 n° 4 (February - March 2003)PermalinkSchätzung von Vegetationsparametern aus multispektralen Fernerkundungsdaten / F. Kurz (2003)PermalinkAssessment of regional forest and scrub productivity using a coupled vegetation process model with remote sensing / Nicholas C. Coops in Geocarto international, vol 17 n° 4 (December 2002 - February 2003)PermalinkIncorporating surface emissivity into a thermal atmospheric correction / N.A. Brunsell in Photogrammetric Engineering & Remote Sensing, PERS, vol 68 n° 12 (December 2002)Permalink