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Spectroscopic analysis of green, desiccated and dead tamarisk canopies / Ran Meng in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 3 (March 2015)
[article]
Titre : Spectroscopic analysis of green, desiccated and dead tamarisk canopies Type de document : Article/Communication Auteurs : Ran Meng, Auteur ; Philip E. Dennison, Auteur Année de publication : 2015 Article en page(s) : pp 199 - 207 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bande infrarouge
[Termes IGN] bande rouge
[Termes IGN] bande spectrale
[Termes IGN] insecte nuisible
[Termes IGN] rayonnement proche infrarouge
[Termes IGN] réflectance végétale
[Termes IGN] risque naturel
[Termes IGN] Tamarix (genre)Résumé : (auteur) Defoliation by the northern tamarisk beetle (Diorhabda carinulata) causes changes in the reflectance of tamarisk (Tamarix spp.) canopies. Cross correlogram spectral matching was used to examine spectral separability of green, yellow desiccated, brown desiccated, and dead tamarisk canopy types. Using a feature selection technique (the instability index), four spectral regions were identified as important for canopy type discrimination, including one red (645-693 nm), one near infrared (735-946 nm), and two shortwave infrared regions (1,960-2,090 nm and 2,400-2,478 nm). The random forests decision tree algorithm was used to compare classification performances of full-range and feature-selected hyperspectral spectra as well as simulated WorldView-2 spectra. Classification results indicated that the process of feature selection can reduce data redundancy and computation time while improving accuracy of tamarisk canopy type classification. Numéro de notice : A2015-969 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.14358/PERS.81.3.199-207 En ligne : https://doi.org/10.14358/PERS.81.3.199-207 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80027
in Photogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 3 (March 2015) . - pp 199 - 207[article]Retrieving surface variables by integrating ground measurements and earth observation data in forest canopies : a case study in Speuldersbos forest / Kitsiri Weligepolage (2015)
Titre : Retrieving surface variables by integrating ground measurements and earth observation data in forest canopies : a case study in Speuldersbos forest Type de document : Thèse/HDR Auteurs : Kitsiri Weligepolage, Auteur Editeur : Enschede [Pays Bas] : University of Twente Année de publication : 2015 Collection : ITC Dissertation num. 269 Importance : 148 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-90-365-3876-3 Note générale : bibliographie
University of Twente, Faculty of Geo-Information and Earth ObservationLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] aiguille
[Termes IGN] albedo
[Termes IGN] canopée
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] Fagus (genre)
[Termes IGN] hauteur des arbres
[Termes IGN] image AHS
[Termes IGN] image thermique
[Termes IGN] modèle numérique de surface de la canopée
[Termes IGN] Pinophyta
[Termes IGN] Pseudotsuga menziesii
[Termes IGN] réflectance végétale
[Termes IGN] rugosité
[Termes IGN] température au solRésumé : (auteur) The main objective of this study is to integrate tower-based measurements with ED data for estimating spatially and temporally distributed surface variables of a forest canopy for improved quantification of surface-atmosphere interactions. This study mainly focuses on three of the most important surface variables for estimating surface fluxes, namely the aerodynamic roughness, land surface albedo and land surface temperature.
In chapter 2, a framework is presented for estimating aerodynamic roughness parameters: the momentum roughness length (z0) and the displacement height (do) of a coniferous forest stand using remote sensing data. The specific objective of the study is to make use of high resolution Terrestrial Laser Scanning (TLS) data together with Airborne Laser Scanning (ALS) data to digitally map the upper canopy surface in order to generate high resolution digital Canopy Height Models (CHMs). The digital CHMs were subsequently used to extract surface geometric parameters of the upper canopy surface. Eventually the surface geometric parameters were used as input variables in the selected morphometric models to estimate aerodynamic roughness parameters. It was observed that the estimated values of zo and do depend very much on the selected model. Comparison of model estimated roughness parameters against the literature values for similar surface types has shown that the technique can be successfully applied to estimate forest surface roughness by tuning some of the model parameters to resemble the forest structure of the study area.
Chapter 3 describes the use of these two aerodynamic methods to estimate momentum roughness length and displacement height of Douglas fir forest using simultaneous micrometeorological and flux measurements. When the flux-gradient method was used to objectively determine zo and do, corrections for roughness sub-layer effects proved to be important. A new iterative method is employed to solve the set of equations when the corrections were made. In the absence of experimentally determined roughness sub-layer height, the corrections of Harman and Finnigan (2007) yielded the best overall estimates of aerodynamic parameters. Comparison with results of over 25 other studies has shown that the results obtained in this work fit the general trend rather well. Two quadratic relationships are proposed to predict do and ha based on the observed mean tree height. These simple relationships can be easily incorporated to large scale land surface models, provided that spatially distributed tree height information is available. The flux-variance technique is shown to be robust even when measurements are made in the roughness sub-layer. However the technique cannot be objectively used to estimate zo and do as no explicit method exists to select the exact value for coefficient C1.
A detailed investigation of stand level surface albedo variability of a patchwork forest is presented in chapter 4. The top of the canopy reflectance in the visible and near-infrared domain retrieved from airborne and satellite imageries were integrated to estimate spatially distributed surface albedo while the tower-based radiation measurements in the solar-reflective region were used to obtain the temporal variation of surface albedo over a needleleaf forest canopy. The diurnal variation of surface albedo is consistent with the previous findings for needleleaf forest canopies. The spatial mean surface albedo values estimated from remote sensing data for needleleaf (pure Douglas fir), broadleaf (pure Beech) and mixed forest classes are 0.09, 0.13 and 0.11 respectively. Both visual characteristics and descriptive statistics indicate that with increased pixel size, the spatial variability of albedo progressively decreases. The semivariogram analysis was more insightful to perceive the nature and causes of albedo spatial variability in different forest classes in relation to sensor spatial resolution.
Finally a theoretical basis for directional LST estimation from top of the atmosphere radiance measurements is presented along with a spatio-temporal analysis of remotely sensed LST and concurrently carried out ground-based radiation together with contact temperature measurements in a Douglas fir forest. For the analysis we used remotely sensed TIR data from Airborne Hyperspectral Scanner to estimate spatially distributed LST of forested area. The AHS sensor, with 10 thermal bands covering the range between 8 and 13pm of the electromagnetic spectrum is an example of the new generation of airborne sensors with multispectral thermal infrared capabilities. The data acquired from the AHS sensors provided the opportunity to retrieve the directional LST of the forest canopy with a very high spatial resolution for both nadir and oblique view angles. Also the concurrent tower-based temperature measurements provided limited ground truth for a spatio-temporal analysis of surface temperature in an area covered with Douglas fir trees. The method adopted here for concurrent determination of LST and LSE is the widely-used TES algorithm together with the MODTRAN4 preprocessor for calculating the required atmospheric contributions. AHS derived average temperature values are generally in good agreement with the tower based component temperature measured at 24 m level whereas the component temperatures (trunk) measured at 17 m are consistently higher. It may be noted that in comparison with off-nadir radiometric temperature the TES method provides average LST with RMSE around 1.9K while the corresponding value with respect to component temperature measured at 24 m is around 1.4 K.Note de contenu : 1- Introduction
2- Estimation of canopy aerodynamic roughness using morphometric methods
3- Effects of sub-layer corrections on the roughness parametrization of a Douglas fir forest
4- Effects of spatial resolution on estimating surface albedo
5- Retrieving directional temperature using multiplatform thermal data
6- Conclusion and recommendationsNuméro de notice : 14944 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Thèse étrangère Note de thèse : PhD : Geo-Information and Earth Observation : University of Twente : 2015 En ligne : https://research.utwente.nl/en/publications/retrieving-surface-variables-by-inte [...] Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77060 Documents numériques
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14944 Retrieving surface variablesAdobe Acrobat PDF Retrieving the stand age from a retrospective detection of multinannual forest changes using Landsat data. Application on the heavily managed maritime pine forest in Southwestern France from a 30-year Landsat time-series (1984–2014) / Dominique Guyon (2015)
Titre : Retrieving the stand age from a retrospective detection of multinannual forest changes using Landsat data. Application on the heavily managed maritime pine forest in Southwestern France from a 30-year Landsat time-series (1984–2014) Type de document : Article/Communication Auteurs : Dominique Guyon, Auteur ; Sylvio Laventure, Auteur ; Thierry Bélouard , Auteur ; Jean-Charles Samalens, Auteur ; Jean-Pierre Wigneron, Auteur Editeur : New York : Institute of Electrical and Electronics Engineers IEEE Année de publication : 2015 Conférence : IGARSS 2015, International Geoscience And Remote Sensing Symposium 26/07/2015 31/07/2015 Milan Italie Proceedings IEEE Importance : pp 1968 - 1971 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] dendrométrie
[Termes IGN] détection de changement
[Termes IGN] dommage matériel
[Termes IGN] image Landsat
[Termes IGN] Landes (40)
[Termes IGN] masque
[Termes IGN] Pinus pinaster
[Termes IGN] réflectance végétale
[Termes IGN] série temporelle
[Termes IGN] tempêteRésumé : (auteur) The availability of Landsat data (Landsat 4, 5, 7 and 8) from ~30 years makes it possible to analyze the forest long term dynamics at high resolution (30m). The performances of the Landsat time-series have been already demonstrated for mapping and monitoring the annual clear-cuts and the storm damage in the Landes Forest, that covers ~1 million ha in southwestern France and that is heavily managed with even-aged stands with rather short rotations after clear-cut harvesting. Our objectives aimed at improving, automating, and enriching these previous methods. This was to operationally produce over the whole Landes Forest not only (1) the annual maps of clear-cutting from 1984 up the current year but also (2) the map of the current age that was derived from the forest change detected every year since 1984. The developed methodology used the time-series of surface reflectance and cloud mask provided for Landsat by USGS and sought to cope the possible absence of cloud-free image during the interest season or the numerous missing data in Landsat 7 images after 2002. The retrospective processing of the Landsat time-series from 1984 to 2014 made it possible the prediction of actual current age with a satisfactory accuracy. Numéro de notice : C2015-056 Affiliation des auteurs : IGN+Ext (2012-2019) Thématique : FORET/IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1109/IGARSS.2015.7326182 Date de publication en ligne : 12/11/2015 En ligne : http://dx.doi.org/10.1109/IGARSS.2015.7326182 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91800 Seeing through shadow: Modelling surface irradiance for topographic correction of Landsat ETM+ data / Tobias Schulmann in ISPRS Journal of photogrammetry and remote sensing, vol 99 (January 2015)
[article]
Titre : Seeing through shadow: Modelling surface irradiance for topographic correction of Landsat ETM+ data Type de document : Article/Communication Auteurs : Tobias Schulmann, Auteur ; Marwan Katurji, Auteur ; Peyman Zawar-Reza, Auteur Année de publication : 2015 Article en page(s) : pp 14 - 24 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] aérosol
[Termes IGN] albedo
[Termes IGN] correction des ombres
[Termes IGN] montagne
[Termes IGN] Nouvelle-Zélande
[Termes IGN] pente
[Termes IGN] réflectance de surface
[Termes IGN] transfert radiatifRésumé : (Auteur) Despite advances in remote sensing, retrieving surface properties at high resolutions in complex terrain is a major challenge. Slope and aspect as well as the topography surrounding a target impact surface insolation and lead to variability in calculated surface reflectance even for homogeneous land cover. Retrieval of surface reflectance is particularly problematic in case of topographic shading, where the total irradiation at the surface is a combination of diffuse irradiation and terrain-reflected irradiation from nearby slopes. To facilitate the retrieval of surface reflectance from high-resolution optical remote sensing, we have explored the feasibility of using a three dimensional radiative transfer code to simulate gridded surface irradiance for a View the MathML source∼37km2 area in the New Zealand Southern Alps. We have tested the sensitivity of simulated irradiance and calculated surface reflectance both in- and outside shaded areas to atmospheric aerosol content, surface albedo, atmospheric boundary layer structure and different solar spectra. Retrieved surface reflectance has been shown to be highly sensitive to atmospheric aerosols and surface albedo, particularly for areas shaded by topography. Not considering atmospheric aerosols in topographic correction can increase derived surface reflectance by well over 50%, while terrain-reflected irradiance can contribute 40% to surface reflectance in shaded areas, even for wider valleys. Both factors should therefore be considered in topographic correction of satellite imagery, even for relatively aerosol-free atmospheres and low surface albedo. Topographic correction for the whole scene was performed with the model settings resulting in the smallest RMSD between surface reflectivity in shaded and unshaded areas of similar land cover. Topographic correction based on 3D radiative transfer simulations has proven to effectively remove topographic effects and almost equalise derived mean reflectance in- and outside shaded areas. While the effective removal of shadows likely requires a higher dynamic range than Landsat’s ETM+ can offer, we suggest further evaluation of this approach in future studies at other sites and with other sensors. Numéro de notice : A2014-634 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2014.10.004 En ligne : https://doi.org/10.1016/j.isprsjprs.2014.10.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75060
in ISPRS Journal of photogrammetry and remote sensing > vol 99 (January 2015) . - pp 14 - 24[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2015011 RAB Revue Centre de documentation En réserve L003 Disponible Motion blur disturbs – the influence of motion-blurred images in photogrammetry / T. Sieberth in Photogrammetric record, vol 29 n° 148 (December 2014 - February 2015)
[article]
Titre : Motion blur disturbs – the influence of motion-blurred images in photogrammetry Type de document : Article/Communication Auteurs : T. Sieberth, Auteur ; R. Wackrow, Auteur ; Jim H. Chandler, Auteur Année de publication : 2014 Article en page(s) : pp 434 – 453 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] flou
[Termes IGN] image à haute résolution
[Termes IGN] tâche claire
[Termes IGN] traitement d'imageRésumé : (Auteur) Unmanned aerial vehicles (UAVs) have become an interesting and active research topic for photogrammetry. Current research is based on images acquired by UAVs which have a high ground resolution and good spectral resolution due to low flight altitudes combined with a high-resolution camera. One of the main problems preventing full automation of data processing of UAV imagery is the unknown degradation effect of blur caused by camera movement during image acquisition. The purpose of this paper is to analyse the influence of blur on photogrammetric image processing. Images with precisely known motion blur were produced to determine the effect. It was found that even small blurs affect normal photogrammetric processes significantly. Although operator intervention might be time consuming, it can ensure that the results are still of acceptable accuracy. Numéro de notice : A2014-649 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/phor.12082 Date de publication en ligne : 16/12/2014 En ligne : https://doi.org/10.1111/phor.12082 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75095
in Photogrammetric record > vol 29 n° 148 (December 2014 - February 2015) . - pp 434 – 453[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 106-2014041 RAB Revue Centre de documentation En réserve L003 Disponible Retrieval of spectral reflectance of high resolution multispectral imagery acquired with an autonomous unmanned aerial vehicle: AggieAir™ / Bushra Zaman in Photogrammetric Engineering & Remote Sensing, PERS, vol 80 n° 12 (December 2014)PermalinkAssessment of crop foliar nitrogen using a novel dual-wavelength laser system and implications for conducting laser-based plant physiology / Jan U.H. Eitel in ISPRS Journal of photogrammetry and remote sensing, vol 97 (November 2014)PermalinkEstimating leaf chlorophyll of barley at different growth stages using spectral indices to reduce soil background and canopy structure effects / Kiyun Yu in ISPRS Journal of photogrammetry and remote sensing, vol 97 (November 2014)PermalinkRecovering quantitative remote sensing products contaminated by thick clouds and shadows using multitemporal dictionary learning / X. Li in IEEE Transactions on geoscience and remote sensing, vol 52 n° 11 tome 1 (November 2014)PermalinkThe Normalization of surface anisotropy effects present in SEVIRI reflectances by using the MODIS BRDF method / Simon Richard Proud in IEEE Transactions on geoscience and remote sensing, vol 52 n° 10 tome 1 (October 2014)PermalinkSpectral-angle-based Laplacian Eigenmaps for non linear dimensionality reduction of hyperspectral imagery / L. Yan in Photogrammetric Engineering & Remote Sensing, PERS, vol 80 n° 9 (September 2014)PermalinkDeriving Predictive relationships of carotenoid content at the canopy level in a conifer forest using hyperspectral imagery and model simulation / Rocío Hernández-Clemente in IEEE Transactions on geoscience and remote sensing, vol 52 n° 8 Tome 2 (August 2014)PermalinkSpectral identification of materials by reflectance spectral library search / Rama Rao Nidamanuri in Geocarto international, vol 29 n° 5 - 6 (August - October 2014)PermalinkCrop type classification by simultaneous use of satellite images of different resolutions / Mark W. Liu in IEEE Transactions on geoscience and remote sensing, vol 52 n° 6 Tome 2 (June 2014)PermalinkLaboratory measurements of plant drying: Implications to estimate moisture content from radiative transfer models in two temperate species / Sara Jurdao in Photogrammetric Engineering & Remote Sensing, PERS, vol 80 n° 5 (May 2014)Permalink