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Tree cover and height estimation in the Fennoscandian tundra-taiga transition zone using multiangular MISR data / J. Heiskanen in Remote sensing of environment, vol 103 n° 1 (15 July 2006)
[article]
Titre : Tree cover and height estimation in the Fennoscandian tundra-taiga transition zone using multiangular MISR data Type de document : Article/Communication Auteurs : J. Heiskanen, Auteur Année de publication : 2006 Article en page(s) : pp 97 - 114 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] arbre (flore)
[Termes IGN] classification par réseau neuronal
[Termes IGN] détection de changement
[Termes IGN] Finlande
[Termes IGN] forêt boréale
[Termes IGN] image Terra-MISR
[Termes IGN] taïga
[Termes IGN] toundraRésumé : (Auteur) The tundra–taiga transition zone stretches around the northern hemisphere separating boreal forest to the south from treeless tundra to the north. Tree cover and height are important variables to characterize this vegetation transition. Accurate continuous fields of tree cover and height would enable the delineation of the forest extent according to different criterion and provide useful data for change detection of this climatically sensitive ecotone. This study examined if multiangular remote sensing data has potential to improve the accuracy of the tree cover and height estimates in relation to nadir-view data. The satellite data consisted of Multi-angle Imaging SpectroRadiometer (MISR) data at 275 m and 1.1 km resolutions. The study area was located in the Fennoscandian tundra–taiga transition zone, in northernmost Finland. The continuous fields of tree cover and height were estimated using neural networks, which were trained and assessed by high-resolution biotope inventory data. The spectral–angular data together produced lower estimation errors than single band nadir, multispectral nadir or single band multiangular data alone. RMSE of the tree cover estimates reduced from 7.8% (relative RMSE 67.4%) to 6.5% (56.1%) at 275 m resolution, and from 5.4% (49.2%) to 4.1% (36.9%) at 1.1 km resolution, when multispectral nadir data were used together with multiangular data. RMSE of the tree height estimates reduced from 2.3 m (44.3%) to 2.0 m (37.6%) and from 1.8 m (35.4%) to 1.3 m (25.4%), respectively. The largest estimation errors occurred in mires and in areas of dense shrub cover, but the use of multiangular data also reduced estimation errors in these areas. The results suggest that directional information has potential to improve the tree cover and height estimates, and hence the accuracy of the land cover change detection in the tundra–taiga transition zone. Copyright Elsevier Numéro de notice : A2006-285 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2006.03.015 En ligne : https://doi.org/10.1016/j.rse.2006.03.015 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28012
in Remote sensing of environment > vol 103 n° 1 (15 July 2006) . - pp 97 - 114[article]Incorporating domain knowledge and spatial relationships into land cover classifications: a rule-based approach / A.E. Daniels in International Journal of Remote Sensing IJRS, vol 27 n°12-13-14 (July 2006)
[article]
Titre : Incorporating domain knowledge and spatial relationships into land cover classifications: a rule-based approach Type de document : Article/Communication Auteurs : A.E. Daniels, Auteur Année de publication : 2006 Article en page(s) : pp 2949 - 2975 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] carte d'occupation du sol
[Termes IGN] classe d'objets
[Termes IGN] classification à base de connaissances
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] données auxiliaires
[Termes IGN] feuillu
[Termes IGN] forêt tropicale
[Termes IGN] interprétation automatique
[Termes IGN] occupation du sol
[Termes IGN] précision de la classificationRésumé : (Auteur) For some tropical regions, remote sensing of land cover yields unacceptable results, particularly as the number of land cover classes increases. This research explores the utility of incorporating domain knowledge and multiple algorithms into land cover classifications via a rule-based algorithm for a series of satellite images. The proposed technique integrates the fundamental, knowledge-based interpretation elements of remote sensing without sacrificing the ease and consistency of automated, algorithm-based processing. Compared with results from a traditional maximum likelihood algorithm, classification accuracy was improved substantially for each of the six land cover classes and all three years in the image series. Use of domain knowledge proved effective in accurately classifying problematic tropical land covers, such as tropical deciduous forest and seasonal wetlands. Results also suggest that ancillary data may be most useful in the classification of historic images, where the greatest improvement was observed relative to results from maximum likelihood. The cost of incorporating contextual knowledge and extensive spatial data sets may be justified, since results from the proposed technique suggest a considerable improvement in accuracy may be achieved. Copyright Taylor & Francis Numéro de notice : A2006-310 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160600567753 En ligne : https://doi.org/10.1080/01431160600567753 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28034
in International Journal of Remote Sensing IJRS > vol 27 n°12-13-14 (July 2006) . - pp 2949 - 2975[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 080-06071 RAB Revue Centre de documentation En réserve L003 Disponible On the optimization and selection of wavelet texture for feature extraction from high-resolution satellite imagery with application towards urban-tree delineation / Y.O. Ouma in International Journal of Remote Sensing IJRS, vol 27 n°1-2 (January 2006)
[article]
Titre : On the optimization and selection of wavelet texture for feature extraction from high-resolution satellite imagery with application towards urban-tree delineation Type de document : Article/Communication Auteurs : Y.O. Ouma, Auteur ; T.G. Ngigi, Auteur ; et al., Auteur Année de publication : 2006 Article en page(s) : pp 73 - 104 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse texturale
[Termes IGN] arbre urbain
[Termes IGN] données multiéchelles
[Termes IGN] extraction automatique
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] image à très haute résolution
[Termes IGN] image multibande
[Termes IGN] image Quickbird
[Termes IGN] optimisation (mathématiques)
[Termes IGN] texture d'image
[Termes IGN] transformation en ondelettesRésumé : (Auteur) Integration of spectral and multi-scale texture is proposed in order to improve the detection and classification of urban-trees from Quickbird imagery. Arguing that spatial -structure semantic information exits at a hierarchy of scales and that texture is a consequence of objects in the hierarchy, multi-scale wavelets decomposition is proposed for the extraction of vertical, horizontal and diagonal texture components. Pre-selection of texture sub-bands is achieved via mean, entropy, variance and second angular moment. The resulting sub-bands are analysed for separability between trees and similarly reflecting features, such as rice-paddy, grass/lawns, open ground and playground, based on KuIlbackLeibler (KL) divergence and Battacharyya distance. The results are ranked and classified with k-means. In comparison with the field data, KL gave the best results with omission and commission error of 4.4%. The proposed methodology has the ability to capture the increased natural variability in reflectance and improved the accuracy by 23.6%, in comparison with spectral-only. Numéro de notice : A2006-059 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160500295885 En ligne : https://doi.org/10.1080/01431160500295885 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27786
in International Journal of Remote Sensing IJRS > vol 27 n°1-2 (January 2006) . - pp 73 - 104[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 080-06011 RAB Revue Centre de documentation En réserve L003 Disponible Estimating forest biomass using small footprint LiDAR data: An individual tree-based approach that incorporates training data / Z.J. Bortolot in ISPRS Journal of photogrammetry and remote sensing, vol 59 n° 6 (November 2005)
[article]
Titre : Estimating forest biomass using small footprint LiDAR data: An individual tree-based approach that incorporates training data Type de document : Article/Communication Auteurs : Z.J. Bortolot, Auteur ; R. Wynne, Auteur Année de publication : 2005 Article en page(s) : pp 342 - 360 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] couvert forestier
[Termes IGN] données de terrain
[Termes IGN] données lidar
[Termes IGN] forêt tempérée
[Termes IGN] houppier
[Termes IGN] lasergrammétrie
[Termes IGN] masse végétale
[Termes IGN] optimisation (mathématiques)
[Termes IGN] Pinus taeda
[Termes IGN] régression
[Termes IGN] sylviculture
[Termes IGN] Virginie (Etats-Unis)Résumé : (Auteur) A new individual tree-based algorithm for determining forest biomass using small footprint LiDAR data was developed and tested. This algorithm combines computer vision and optimization techniques to become the first training data-based algorithm specifically designed for processing forest LiDAR data. The computer vision portion of the algorithm uses generic properties of trees in small footprint LiDAR canopy height models (CHMs) to locate trees and find their crown boundaries and heights. The ways in which these generic properties are used for a specific scene and image type is dependent on 11 parameters, nine of which are set using training data and the Nelder-Mead simplex optimization procedure. Training data consist of small sections of the LiDAR data and corresponding ground data. After training, the biomass present in areas without ground measurements is determined by developing a regression equation between properties derived from the LiDAR data of the training stands and biomass, and then applying the equation to the new areas. A first test of this technique was performed using 25 plots (radius = 15 m) in a loblolly pine plantation in central Virginia, USA (37.42N, 78.68W) that was not intensively managed, together with corresponding data from a LiDAR canopy height model (resolution = 0.5 m). Results show correlations (r) between actual and predicted aboveground biomass ranging between 0.59 and 0.82, and RMSEs between 13.6 and 140.4 t/ha depending on the selection of training and testing plots, and the minimum diameter at breast height (7 or 10 cm) of trees included in the biomass estimate. Correlations between LiDAR-derived plot density estimates were low (0.22 Numéro de notice : A2005-490 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2005.07.001 En ligne : https://doi.org/10.1016/j.isprsjprs.2005.07.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27626
in ISPRS Journal of photogrammetry and remote sensing > vol 59 n° 6 (November 2005) . - pp 342 - 360[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-05041 SL Revue Centre de documentation Revues en salle Disponible Effects of forest environment and survey protocol on GPS accuracy / Christian Piedallu in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 9 (September 2005)
[article]
Titre : Effects of forest environment and survey protocol on GPS accuracy Type de document : Article/Communication Auteurs : Christian Piedallu, Auteur ; Jean-Claude Gégout, Auteur Année de publication : 2005 Article en page(s) : pp 1070 - 1078 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] acquisition de données
[Termes IGN] affaiblissement géométrique de la précision
[Termes IGN] analyse comparative
[Termes IGN] antenne GPS
[Termes IGN] correction différentielle
[Termes IGN] couvert forestier
[Termes IGN] feuillu
[Termes IGN] forêt
[Termes IGN] GPS en mode différentiel
[Termes IGN] instrumentation Trimble
[Termes IGN] positionnement par GPS
[Termes IGN] précision de localisation
[Termes IGN] récepteur GPS
[Termes IGN] ressources naturelles
[Termes IGN] saisonRésumé : (Auteur) The aim of the study is to test GPS equipment receivers commonly used for natural resource management, and to quantify recording rate and positioning quality under different conditions, the objective being to assist GPS users in their choices. Four factors were evaluated: (a) the type of receiver: three ranges of GPS equipment were compared; (b) forest cover effects (three covers were tested: open cover, coppice and deciduous high forest); (c) the effects of GPS survey components: the number of recordings (between 1 and 300), the Position Dilution of Precision (PDOP) thresholding (between 4 and 50), the time interval between recordings (between 1 and 15 seconds), and the differential correction effect; and (d) the season (winter and summer). A GPS survey was carried out and a database of 140,000 readings was established, from which a large number of random rover files were extracted for each combination of factors. It appears the only factor not to be significant is the seasonal effect. The type of equipment used and the forest cover effect both modify positioning accuracy by a factor of 2 or 3, as does the use of differential correction for Trimble receivers in open cover. Increasing the number of recordings and the time interval between recordings, and decreasing the PDOP threshold, improve precision, with a different effect according to the GPS receiver and the forest cover. The effect is generally more pronounced under high forest cover. The combined effects of GPS survey components produce significant changes in accuracy at the expense of the time spent in acquiring data. Numéro de notice : A2005-390 Affiliation des auteurs : non IGN Thématique : FORET/POSITIONNEMENT Nature : Article DOI : 10.14358/PERS.71.9.1071 En ligne : https://doi.org/10.14358/PERS.71.9.1071 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27526
in Photogrammetric Engineering & Remote Sensing, PERS > vol 71 n° 9 (September 2005) . - pp 1070 - 1078[article]Mapping tropical forest structure in south-eastern Madagascar using remote sensing and artificial neural networks / J.C. Ingram in Remote sensing of environment, vol 94 n° 4 (28/02/2005)PermalinkMise en place d'un réseau français d'arboretums pour une valorisation coordonnée des ressources ligneuses ex situ / Stéphanie Brachet (2005)PermalinkThird expert meeting on harmonizing forest-related definitions for use by various stakeholders, Rome, Italy, 17 - 19 January 2005 / Wulf Killmann (2005)PermalinkLIDAR-based geometric reconstruction of boreal type forest stands at single tree level for forest and wildland fire management / F. Morsdorf in Remote sensing of environment, vol 92 n° 3 (30 August 2004)PermalinkWavelet transform applied to EO-1 hyperspectral data for forest LAI and crown closure mapping / R. Pu in Remote sensing of environment, vol 91 n° 2 (30/05/2004)PermalinkSeeing the trees in the forest: Using Lidar and multispectral data fusion with local filtering and variable window size for estimating tree height / S.C. Pospecu in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 5 (May 2004)PermalinkEstimation of timber volume and stem density based on scanning laser altimetry and expected tree size distribution functions / Matti Maltamo in Remote sensing of environment, vol 90 n° 3 (15/04/2004)PermalinkThe spatial distribution of indigenous forest and its composition in the Wellington region, New Zealand, from ETM+ satellite imagery / J.R. Dymond in Remote sensing of environment, vol 90 n° 1 (15/03/2004)PermalinkAutomated classification of aerial photographs: detection of forest borders and single trees / André Dufour in Geoinformatics, vol 7 n° 2 (01/03/2004)PermalinkToward universal broad leaf chlorophyll indices using PROSPECT simulated database and hyperspectral reflectance measurements / G. Le Maire in Remote sensing of environment, vol 89 n° 1 (15/01/2004)Permalink