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Above ground biomass estimation in an African tropical forest with lidar and hyperspectral data / Gaia Vaglio Laurin in ISPRS Journal of photogrammetry and remote sensing, vol 89 (March 2014)
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Titre : Above ground biomass estimation in an African tropical forest with lidar and hyperspectral data Type de document : Article/Communication Auteurs : Gaia Vaglio Laurin, Auteur ; Qi Chen, Auteur ; Jeremy A. Lindsell, Auteur ; David A. Coomes, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 49 - 58 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] Afrique tropicale
[Termes IGN] bilan du carbone
[Termes IGN] biomasse
[Termes IGN] données lidar
[Termes IGN] forêt tropicale
[Termes IGN] image hyperspectrale
[Termes IGN] modélisation de la forêtRésumé : (Auteur) The estimation of above ground biomass in forests is critical for carbon cycle modeling and climate change mitigation programs. Small footprint lidar provides accurate biomass estimates, but its application in tropical forests has been limited, particularly in Africa. Hyperspectral data record canopy spectral information that is potentially related to forest biomass. To assess lidar ability to retrieve biomass in an African forest and the usefulness of including hyperspectral information, we modeled biomass using small footprint lidar metrics as well as airborne hyperspectral bands and derived vegetation indexes. Partial Least Square Regression (PLSR) was adopted to cope with multiple inputs and multicollinearity issues; the Variable of Importance in the Projection was calculated to evaluate importance of individual predictors for biomass. Our findings showed that the integration of hyperspectral bands (R2 = 0.70) improved the model based on lidar alone (R2 = 0.64), this encouraging result call for additional research to clarify the possible role of hyperspectral data in tropical regions. Replacing the hyperspectral bands with vegetation indexes resulted in a smaller improvement (R2 = 0.67). Hyperspectral bands had limited predictive power (R2 = 0.36) when used alone. This analysis proves the efficiency of using PLSR with small-footprint lidar and high resolution hyperspectral data in tropical forests for biomass estimation. Results also suggest that high quality ground truth data is crucial for lidar-based AGB estimates in tropical African forests, especially if airborne lidar is used as an intermediate step of upscaling field-measured AGB to a larger area. Numéro de notice : A2014-124 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2014.01.001 En ligne : https://doi.org/10.1016/j.isprsjprs.2014.01.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33029
in ISPRS Journal of photogrammetry and remote sensing > vol 89 (March 2014) . - pp 49 - 58[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2014031 RAB Revue Centre de documentation En réserve L003 Disponible Assessing changes in species distribution from sequential large-scale forest inventories / Laura Hernandez in Annals of Forest Science, vol 71 n° 2 (March 2014)
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Titre : Assessing changes in species distribution from sequential large-scale forest inventories Type de document : Article/Communication Auteurs : Laura Hernandez, Auteur ; Isabel Canellas, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 161 - 171 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] changement climatique
[Termes IGN] Espagne
[Termes IGN] espèce végétale
[Termes IGN] estimation statistique
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] phytogéographie
[Termes IGN] Pyrénées (montagne)
[Termes IGN] répartition géographiqueRésumé : (Auteur) Context: It is assumed that global change is already affecting the composition, structure and distribution of forest ecosystems; however, detailed evidences of altitudinal and latitudinal shifts are still scarce. • Aims: To develop a method based on National Forest Inventory (NFI) to assess spatio-temporal changes in species distributions. • Methods: We develop an approach based on universal kriging to compare species distribution models from the different NFI cycles and regardless of the differences in the sampling schemes used. Furthermore, a confidence interval approach is used to assess significant changes in species distribution. The approach is applied to some of the southernmost populations of Pinus sylvestris and Fagus sylvatica in the Western Pyrenees over the last 40 years. • Results: An increase of the presence of the two species in the region was observed. Scots pine distribution has shifted about 1.5 km northwards over recent decades, whereas the European beech has extended its distribution southwards by about 2 km. Furthermore, the optimum altitude for both species has risen by about 200 m. As a result, the zone in which the two species coexist has been enlarged. • Conclusions: This approach provides a useful tool to compare NFI data from different sampling schemes, quantifying and testing significant shifts in tree species distribution over recent decades across geographical gradients. Numéro de notice : A2014-050 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s13595-013-0308-6 Date de publication en ligne : 12/07/2013 En ligne : https://doi.org/10.1007/s13595-013-0308-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32955
in Annals of Forest Science > vol 71 n° 2 (March 2014) . - pp 161 - 171[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 016-2014021 SL Revue Centre de documentation Revues en salle Disponible Données géographiques et construction institutionnelle d’une région transnationale. Le SOIA comme objet-frontière ? / Raphael Pieroni in Revue internationale de géomatique, vol 24 n° 1 (mars – mai 2014)
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Titre : Données géographiques et construction institutionnelle d’une région transnationale. Le SOIA comme objet-frontière ? Type de document : Article/Communication Auteurs : Raphael Pieroni, Auteur ; Bernard Debarbieux, Auteur Année de publication : 2014 Article en page(s) : pp 67 - 85 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Infrastructure de données
[Termes IGN] Alpes
[Termes IGN] carte transfrontalière
[Termes IGN] France (administrative)
[Termes IGN] frontière
[Termes IGN] infrastructure nationale des données localisées
[Termes IGN] institution administrative
[Termes IGN] région
[Termes IGN] Suisse
[Termes IGN] système d'information géographiqueRésumé : (Auteur) Le rôle des bases de données géographiques dans le processus de construction régionale est resté à ce jour très marginal au sein des études régionales. Cet article étudie dans quelle mesure de telles bases de données constituent un opérateur, une modalité de l’institutionnalisation d’une région transnationale émergente. Il mobilise pour cela les concepts d’objet-intermédiaire et d’objet-frontière, adoptés avec succès en anthropologie des sciences et des techniques. L’article se propose de le faire à l’échelle du périmètre de la Convention alpine avec une attention particulière portée sur le Système d’observation et d’information des Alpes (SOIA). Il montre que les difficultés apparaissant dans la création du SOIA sont révélatrices de celles rencontrées dans la construction institutionnelle de la Convention alpine. Cet article repose sur un corpus d’une dizaine d’entretiens étendus ainsi que de nombreux rapports internes aux institutions concernées. Numéro de notice : A2014-179 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.3166/rig.24.67-85 En ligne : https://doi.org/10.3166/rig.24.67-85 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33084
in Revue internationale de géomatique > vol 24 n° 1 (mars – mai 2014) . - pp 67 - 85[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 047-2014011 SL Revue Centre de documentation Revues en salle Disponible Oceanwide precise determination of sea surface height from in-situ measurements on cargo ships / Ole Roggenbuck in Marine geodesy, vol 37 n° 1 (March - May 2014)
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Titre : Oceanwide precise determination of sea surface height from in-situ measurements on cargo ships Type de document : Article/Communication Auteurs : Ole Roggenbuck, Auteur ; Jörg Reinking, Auteur ; Alexander Härting, Auteur Année de publication : 2014 Article en page(s) : pp 77 - 96 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse comparative
[Termes IGN] données GNSS
[Termes IGN] données Jason
[Termes IGN] hauteurs de mer
[Termes IGN] Pacifique (océan)
[Termes IGN] précision centimétrique
[Vedettes matières IGN] AltimétrieRésumé : (Auteur) Thanks to the latest developments in GNSS data processing the antenna heights aboard a ship can be determined with accuracies of up to 5 cm, also in the open ocean. These heights are a good basis to derive precise in-situ data of sea surface heights independently from satellite altimetry. However, for a reliable determination of sea surface heights, some essential hydrostatic and hydrodynamic corrections must be considered, as explained in this paper. Furthermore, an ocean wide determination of sea surface height from measurements on a container ship in the Pacific Ocean is presented. The results are compared with those from the Jason-2 altimeter. Numéro de notice : A2015-164 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1080/01490419.2013.868385 Date de publication en ligne : 14/01/2019 En ligne : https://doi.org/10.1080/01490419.2013.868385 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75851
in Marine geodesy > vol 37 n° 1 (March - May 2014) . - pp 77 - 96[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 230-2014011 RAB Revue Centre de documentation En réserve L003 Disponible The impact of the dynamic sea surface topography on the quasi-geoid in shallow coastal waters / D.C. Slobbe in Journal of geodesy, vol 88 n° 3 (March 2014)
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Titre : The impact of the dynamic sea surface topography on the quasi-geoid in shallow coastal waters Type de document : Article/Communication Auteurs : D.C. Slobbe, Auteur ; R. Klees, Auteur Année de publication : 2014 Article en page(s) : pp 241 - 261 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] levé gravimétrique
[Termes IGN] marée océanique
[Termes IGN] Nord, mer du
[Termes IGN] quasi-géoïde
[Termes IGN] surface de la mer
[Termes IGN] topographieRésumé : (Auteur) In this study, we examine the impact of instantaneous dynamic sea surface topography (DT) corrections to be applied to altimeter-derived sea surface slopes on the quasi-geoid in the shallow and coastal waters of the North Sea. In particular, we investigate the added value of DT corrections obtained from a shallow-water hydrodynamic model. These corrections comprise the contributions of ocean tides, wind- and pressure-driven (surge), and density-driven (baroclinic) water-level variations including the interactions between them. As a reference, we used tidal corrections derived from the global ocean tide model GOT4.7, surge corrections derived from the MOG2D model, and corrections for the time-averaged baroclinic contribution computed as differences between the DTU10 mean sea surface model and the EGG08 quasi-geoid. From a spectral analysis, we found that the baroclinic and surge parts of the DT mainly contribute to improvements in the signal-to-noise ratio (SNR) at longer wavelengths down to 100200 km and that the improvements increase towards the southern North Sea. We also found that the shallow-water hydrodynamic model provides better tidal corrections compared to the GOT4.7 global ocean tide model, which are most pronounced in the southern North Sea and affect almost the entire spectrum. Very small differences (mostly below +2 cm ) are observed between the quasi-geoid solutions obtained using the different sets of DT corrections. We showed that the variance component estimation provides too optimistic variance factors for the shipboard data set relative to the altimeter-derived quasi-geoid slopes. Hence, the limited impact of DT corrections is due to the fact that altimeter-derived quasi-geoid slopes hardly contribute to the estimated quasi-geoid if shipboard gravity data are included. When computing quasi-geoid solutions without shipboard gravity data, we found that less accurate or incomplete DT corrections may cause errors in the quasi-geoid with systematic spatial patterns. These systematic patterns disappear or are reduced significantly when using the DT corrections provided by the shallow-water hydrodynamic model. The main contributor to this improvement is the better tidal correction provided by the shallow-water hydrodynamic model compared to the GOT4.7 global ocean tide model. Seen the improvements of the global ocean tide models over the last two decades, we expect that in the near future global ocean tide models perform as well as dedicated regional models such as DCSM. Critical issue is, however, access to high-quality local bathymetric data. Numéro de notice : A2014-134 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-013-0679-3 Date de publication en ligne : 18/12/2013 En ligne : https://doi.org/10.1007/s00190-013-0679-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33039
in Journal of geodesy > vol 88 n° 3 (March 2014) . - pp 241 - 261[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2014031 SL Revue Centre de documentation Revues en salle Disponible Vallée des merveilles : relevés topographiques et SIG archéologique / Gabriel Vatin in XYZ, n° 138 (mars - mai 2014)
PermalinkApplication of frequency ratio and likelihood ratio model for geo-spatial modelling of landslide hazard vulnerability assessment and zonation: a case study from the Sikkim Himalayas in India / L.P. Sharma in Geocarto international, vol 29 n° 1 - 2 (February - April 2014)
PermalinkPlusieurs scanners pour surveiller une rampe / Vincent Barras in Géomatique suisse, vol 112 n° 2 (01/02/2014)
PermalinkSpatial patterns of historical growth changes in Norway spruce across western European mountains and the key effect of climate warming / Marie Charru in Trees, vol 28 n° 1 (February 2014)
PermalinkBilan énergétique de la France pour 2013 / CGDD Commissariat Général au Développement Durable (2014)
PermalinkEvaluation of MODIS data for improved monitoring of the Caspian Sea / Ayoub Moradi in International Journal of Remote Sensing IJRS, vol 35 n° 16 (January 2014)
PermalinkPermalinkLes indicateurs de développement durable pour les territoires, édition 2014 / CGDD Commissariat Général au Développement Durable (2014)
PermalinkIndividual tree segmentation over large areas using airborne LiDAR point cloud and very high resolution optical imagery / Yuchu Qin (2014)
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PermalinkMethod comparisons of forest attribute estimations based on different remote sensing sources, including Lidar. The Vosges case study / Nicolas Py (2014)
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