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Laser scanning based growth analysis of plants as a new challenge for deformation monitoring / Jan Dupuis in Journal of applied geodesy, vol 10 n° 1 (March 2016)
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[article]
Titre : Laser scanning based growth analysis of plants as a new challenge for deformation monitoring Type de document : Article/Communication Auteurs : Jan Dupuis, Auteur ; Christoph Holst, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2016 Article en page(s) : pp 37 - 44 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes descripteurs IGN] B-Spline
[Termes descripteurs IGN] croissance végétale
[Termes descripteurs IGN] déformation géométrique
[Termes descripteurs IGN] données lidar
[Termes descripteurs IGN] données localisées 3D
[Termes descripteurs IGN] feuille (végétation)
[Termes descripteurs IGN] maillage par triangles
[Termes descripteurs IGN] tessellationRésumé : (auteur) Nowadays, the areal deformation analysis has become an important task in engineering geodesy. Thereby, not only manmade objects are of high interest, also natural objects, like plant organs, are focused more frequently. Thus, the analysis of leaf growth, i. e. the spatial development of the leaf surface, can be seen as a problem of deformation monitoring. In contrast to classical geodetic tasks, the absolute size of the deformation of the leaf surface is small, but usually great compared to the object size. Due to the optical characteristics of leaf surfaces, the point clouds, commonly acquired with high precision close-up laser scanners, provide a point-to-point distance that is small or equal compared to the measurement accuracy. Thus, the point clouds are usually processed and the leaf area is derived from a triangulation-based surface representation (mesh), resulting in a significant uncertainty of area calculation. In this paper, we illustrate the lacks of the mesh-based leaf area calculation. Using high precision gauge blocks as well as a number of tomato leaves, uncertainties of the area derivation are revealed and evaluated. The application of a B-spline approximation illustrates the advantages of an approximation-based approach and introduces the prospect for further research. Numéro de notice : A2016-552 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article En ligne : http://dx.doi.org/10.1515/jag-2015-0028 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81698
in Journal of applied geodesy > vol 10 n° 1 (March 2016) . - pp 37 - 44[article]Changes in thermal infrared spectra of plants caused by temperature and water stress / Maria F. Buitrago in ISPRS Journal of photogrammetry and remote sensing, vol 111 (January 2016)
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[article]
Titre : Changes in thermal infrared spectra of plants caused by temperature and water stress Type de document : Article/Communication Auteurs : Maria F. Buitrago, Auteur ; Thomas A. Groen, Auteur ; Christoph A. Hecker, Auteur ; Andrew K. Skidmore, Auteur Année de publication : 2016 Article en page(s) : pp 22 – 31 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes descripteurs IGN] bruit thermique
[Termes descripteurs IGN] détection de changement
[Termes descripteurs IGN] feuille (végétation)
[Termes descripteurs IGN] image thermique
[Termes descripteurs IGN] végétationRésumé : (auteur) Environmental stress causes changes in leaves and the structure of plants. Although physiological adaptations to stress by plants have been explored, the effect of stress on the spectral properties in the thermal part of the electromagnetic spectrum (3–16 μm) has not yet been investigated.
In this research two plant species (European beech, Fagus sylvatica and rhododendron, Rhododendron cf. catawbiense) that both grow naturally under temperature limited conditions were selected, representing deciduous and evergreen plants respectively. Besides TIR spectra, Leaf Water Content (LWC) and cuticle thickness were measured as possible variables that can explain the changes in TIR spectra.
The results demonstrated that both species, when exposed to either water or temperature stress, showed significant changes in their TIR spectra. The changes in TIR in response to stress were similar within a species, regardless of the stress imposed on them. However, changes in TIR spectra differed between species. For rhododendron emissivity in TIR increased under stress while for beech it decreased. Both species showed depletion of Leaf Water Content (LWC) under stress, ruling LWC out as a main cause for the change in the TIR spectra. Cuticle thickness remained constant for beech, but increased for rhododendron. This suggests that changes in emissivity may be linked to changes in the cuticle thickness and possibly the structure of cuticle. It is known that spectral changes in this region have a close connection with microstructure and biochemistry of leaves. We propose detailed measurements of these changes in the cuticle to analyze the effect of microstructure on TIR spectra.Numéro de notice : A2016-038 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.11.003 date de publication en ligne : 08/12/2015 En ligne : https://doi.org/10.1016/j.isprsjprs.2015.11.003 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79517
in ISPRS Journal of photogrammetry and remote sensing > vol 111 (January 2016) . - pp 22 – 31[article]Microwave unmixing with video segmentation for inferring broadleaf and needleleaf brightness temperatures and abundances from mixed forest observations / Lingjia Gu in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)
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Titre : Microwave unmixing with video segmentation for inferring broadleaf and needleleaf brightness temperatures and abundances from mixed forest observations Type de document : Article/Communication Auteurs : Lingjia Gu, Auteur ; Kai Zhao, Auteur ; Bormin Huang, Auteur Année de publication : 2016 Article en page(s) : pp 279 - 286 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes descripteurs IGN] aiguille
[Termes descripteurs IGN] densité de la végétation
[Termes descripteurs IGN] feuille (végétation)
[Termes descripteurs IGN] peuplement forestier
[Termes descripteurs IGN] peuplement mélangé
[Termes descripteurs IGN] segmentation d'image
[Termes descripteurs IGN] traitement d'image
[Termes descripteurs IGN] vidéo numériqueRésumé : (Auteur) Passive microwave sensors have better capability of penetrating forest layers to obtain more information from forest canopy and ground surface. For forest management, it is useful to study passive microwave signals from forests. Passive microwave sensors can detect signals from needleleaf, broadleaf, and mixed forests. The observed brightness temperature of a mixed forest can be approximated by a linear combination of the needleleaf and broadleaf brightness temperatures weighted by their respective abundances. For a mixed forest observed by an N-band microwave radiometer with horizontal and vertical polarizations, there are 2 N observed brightness temperatures. It is desirable to infer 4 N + 2 unknowns: 2 N broadleaf brightness temperatures, 2 N needleleaf brightness temperatures, 1 broadleaf abundance, and 1 needleleaf abundance. This is a challenging underdetermined problem. In this paper, we devise a novel method that combines microwave unmixing with video segmentation for inferring broadleaf and needleleaf brightness temperatures and abundances from mixed forests. We propose an improved Otsu method for video segmentation to infer broadleaf and needleleaf abundances. The brightness temperatures of needleleaf and broadleaf trees can then be solved by the nonnegative least squares solution. For our mixed forest unmixing problem, it turns out that the ordinary least squares solution yields the desired positive brightness temperatures. The experimental results demonstrate that the proposed method is able to unmix broadleaf and needleleaf brightness temperatures and abundances well. The absolute differences between the reconstructed and observed brightness temperatures of the mixed forest are well within 1 K. Numéro de notice : A2016-069 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern En ligne : http://dx.doi.org/10.1109/TGRS.2015.2455151 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79831
in IEEE Transactions on geoscience and remote sensing > vol 54 n° 1 (January 2016) . - pp 279 - 286[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2016011 SL Revue Centre de documentation Revues en salle Disponible Combining leaf physiology, hyperspectral imaging and partial least squares-regression (PLS-R) for grapevine water status assessment / Tal Rapaport in ISPRS Journal of photogrammetry and remote sensing, vol 109 (November 2015)
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Titre : Combining leaf physiology, hyperspectral imaging and partial least squares-regression (PLS-R) for grapevine water status assessment Type de document : Article/Communication Auteurs : Tal Rapaport, Auteur Année de publication : 2015 Article en page(s) : pp 88 - 97 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes descripteurs IGN] bande visible
[Termes descripteurs IGN] bilan hydrique
[Termes descripteurs IGN] feuille (végétation)
[Termes descripteurs IGN] image hyperspectrale
[Termes descripteurs IGN] méthode des moindres carrés
[Termes descripteurs IGN] rayonnement proche infrarouge
[Termes descripteurs IGN] régression
[Termes descripteurs IGN] teneur en eau de la végétation
[Termes descripteurs IGN] viticultureRésumé : (auteur) Physiological measurements are considered to be the most accurate way of assessing plant water status, but they might also be time-consuming, costly and intrusive. Since visible (VIS)-to-shortwave infrared (SWIR) imaging spectrometers are able to monitor various bio-chemical alterations in the leaf, such narrow-band instruments may offer a faster, less expensive and non-destructive alternative. This requires an intelligent downsizing of broad and noisy hyperspectra into the few most physiologically-sensitive wavelengths. In the current study, hyperspectral signatures of water-stressed grapevine leaves (Vitis vinifera L. cv. Cabernet Sauvignon) were correlated to values of midday leaf water potential (Ψl), stomatal conductance (gs) and non-photochemical quenching (NPQ) under controlled conditions, using the partial least squares-regression (PLS-R) technique. It was found that opposite reflectance trends at 530–550 nm and around 1500 nm – associated with independent changes in photoprotective pigment contents and water availability, respectively – were indicative of stress-induced alterations in Ψl, gs and NPQ. Furthermore, combining the spectral responses at these VIS and SWIR regions yielded three normalized water balance indices (WABIs), which were superior to various widely-used reflectance models in predicting physiological values at both the leaf and canopy levels. The potential of the novel WABI formulations also under field conditions demonstrates their applicability for water status monitoring and irrigation scheduling. Numéro de notice : A2015-857 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern En ligne : http://dx.doi.org/10.1016/j.isprsjprs.2015.09.003 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79239
in ISPRS Journal of photogrammetry and remote sensing > vol 109 (November 2015) . - pp 88 - 97[article]Evaluating the impact of leaf-on and leaf-off airborne laser scanning data on the estimation of forest inventory attributes with the area-based approach / Joanne C. White in Canadian Journal of Forest Research, vol 45 n° 11 (November 2015)
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Titre : Evaluating the impact of leaf-on and leaf-off airborne laser scanning data on the estimation of forest inventory attributes with the area-based approach Type de document : Article/Communication Auteurs : Joanne C. White, Auteur ; John T.T.R. Arnett, Auteur ; Michael A. Wulder, Auteur ; Piotr Tompalski, Auteur ; Nicholas C. Coops, Auteur Année de publication : 2015 Article en page(s) : pp 1498 - 1513 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes descripteurs IGN] Alberta (Canada)
[Termes descripteurs IGN] données lidar
[Termes descripteurs IGN] données localisées 3D
[Termes descripteurs IGN] feuille (végétation)
[Termes descripteurs IGN] feuillu
[Termes descripteurs IGN] hauteur des arbres
[Termes descripteurs IGN] inventaire forestier étranger (données)
[Termes descripteurs IGN] modèle numérique de surface
[Termes descripteurs IGN] pinophyta
[Termes descripteurs IGN] Pinus contorta
[Termes descripteurs IGN] placette d'échantillonnageRésumé : (auteur) Dans cette étude, nous explorons les conséquences de l’utilisation des données de balayage laser aéroporté (BLA), acquises avec ou sans feuilles, sur les résultats d’un modèle par surface dans une forêt dominée par le pin tordu latifolié (Pinus contorta var. latifolia Engelm.) dans les contreforts des montagnes Rocheuses en Alberta, au Canada. Nous avons examiné huit caractéristiques de la forêt : la hauteur dominante, la hauteur moyenne, la hauteur moyenne de Lorey, la surface terrière, le diamètre moyen quadratique, le volume marchand, le volume total et la biomasse aérienne totale. Nous avons utilisé 787 placettes au sol pour l’élaboration du modèle, stratifiées par les conditions d’acquisition du BLA (avec ou sans feuilles) et le type forestier dominant (conifères ou feuillus). Nous avons également généré des modèles regroupés qui combinaient les données de BLA avec feuilles aux données sans feuilles, et des modèles génériques qui combinent les données des placettes de tous les types forestiers. Nous avons évalué les différences dans les mesures de BLA et les résultats des modèles avec ou sans feuilles, ainsi que les impacts du regroupement des données de BLA avec et sans feuilles, de la création de modèles génériques et de l’application des modèles étalonnés avec feuilles aux données sans feuilles (et vice versa). En général, les mesures de BLA avec et sans feuilles n’étaient pas significativement différentes (p Numéro de notice : A2015-671 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article En ligne : http://www.nrcresearchpress.com/doi/full/10.1139/cjfr-2015-0192 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78287
in Canadian Journal of Forest Research > vol 45 n° 11 (November 2015) . - pp 1498 - 1513[article]Modeling of the permittivity of holly leaves in frozen environments / Xiaokang Kou in IEEE Transactions on geoscience and remote sensing, vol 53 n° 11 (November 2015)
PermalinkA geometric method for wood-leaf separation using terrestrial and simulated Lidar data / Shengli Tao in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 10 (October 2015)
PermalinkEvaluating leaf chlorophyll content prediction from multispectral remote sensing data within a physically-based modelling framework / H. Croft in ISPRS Journal of photogrammetry and remote sensing, vol 102 (April 2015)
PermalinkRetrieving surface variables by integrating ground measurements and earth observation data in forest canopies : a case study in Speuldersbos forest / Kitsiri Weligepolage (2015)
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Permalink3D tree reconstruction from simulated small footprint waveform lidar / Jiaying Wu in Photogrammetric Engineering & Remote Sensing, PERS, vol 79 n° 12 (December 2013)
Permalink3-D voxel-based solid modeling of a broad-leaved tree for accurate volume estimation using portable scanning lidar / Fumiki Hosoi in ISPRS Journal of photogrammetry and remote sensing, vol 82 (August 2013)
PermalinkAssessing the impact of hydrocarbon leakages on vegetation using reflectance spectroscopy / I.D. Sanches in ISPRS Journal of photogrammetry and remote sensing, vol 78 (April 2013)
PermalinkMulti-wavelength canopy LiDAR for remote sensing of vegetation: Design and system performance / G. Wei in ISPRS Journal of photogrammetry and remote sensing, vol 69 (April 2012)
PermalinkLeaf morphological analyses in four European oak species (Quercus) and their hybrids: A comparison of traditional and geometric morphometric methods / Vicenzo Viscosi in Plant Biosystems, vol 143 n° 3 (November 2009)
PermalinkComparing needle and shoot phenology with xylem development on three conifer species in Italy / Sergio Rossi in Annals of Forest Science, Vol 66 n° 2 (march 2009)
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