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Mapping dead forest cover using a deep convolutional neural network and digital aerial photography / Jean-Daniel Sylvain in ISPRS Journal of photogrammetry and remote sensing, vol 156 (October 2019)
[article]
Titre : Mapping dead forest cover using a deep convolutional neural network and digital aerial photography Type de document : Article/Communication Auteurs : Jean-Daniel Sylvain, Auteur ; Guillaume Drolet, Auteur ; Nicolas Brown, Auteur Année de publication : 2019 Article en page(s) : pp 14 - 26 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] apprentissage profond
[Termes IGN] arbre mort
[Termes IGN] base de données forestières
[Termes IGN] classification par réseau neuronal convolutif
[Termes IGN] couvert forestier
[Termes IGN] feuillu
[Termes IGN] forêt boréale
[Termes IGN] image aérienne
[Termes IGN] orthoimage
[Termes IGN] peuplement mélangé
[Termes IGN] Pinophyta
[Termes IGN] Québec (Canada)
[Termes IGN] santé des forêtsRésumé : (Auteur) Tree mortality is an important forest ecosystem variable having uses in many applications such as forest health assessment, modelling stand dynamics and productivity, or planning wood harvesting operations. Because tree mortality is a spatially and temporally erratic process, rates and spatial patterns of tree mortality are difficult to estimate with traditional inventory methods. Remote sensing imagery has the potential to detect tree mortality at spatial scales required for accurately characterizing this process (e.g., landscape, region). Many efforts have been made in this sense, mostly using pixel- or object-based methods. In this study, we explored the potential of deep Convolutional Neural Networks (CNNs) to detect and map tree health status and functional type over entire regions. To do this, we built a database of around 290,000 photo-interpreted trees that served to extract and label image windows from 20 cm-resolution digital aerial images, for use in CNN training and evaluation. In this process, we also evaluated the effect of window size and spectral channel selection on classification accuracy, and we assessed if multiple realizations of a CNN, generated using different weight initializations, can be aggregated to provide more robust predictions. Finally, we extended our model with 5 additional classes to account for the diversity of landcovers found in our study area. When predicting tree health status only (live or dead), we obtained test accuracies of up to 94%, and up to 86% when predicting functional type only (broadleaf or needleleaf). Channel selection had a limited impact on overall classification accuracy, while window size increased the ability of the CNNs to predict plant functional type. The aggregation of multiple realizations of a CNN allowed us to avoid the selection of suboptimal models and help to remove much of the speckle effect when predicting on new aerial images. Test accuracies of plant functional type and health status were not affected in the extended model and were all above 95% for the 5 extra classes. Our results demonstrate the robustness of the CNN for between-scene variations in aerial photography and also suggest that this approach can be applied at operational level to map tree mortality across extensive territories. Numéro de notice : A2019-316 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2019.07.010 Date de publication en ligne : 02/08/2019 En ligne : https://doi.org/10.1016/j.isprsjprs.2019.07.010 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93353
in ISPRS Journal of photogrammetry and remote sensing > vol 156 (October 2019) . - pp 14 - 26[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2019101 RAB Revue Centre de documentation En réserve L003 Disponible 081-2019103 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2019102 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt The utility of terrestrial photogrammetry for assessment of tree volume and taper in boreal mixedwood forests / Christopher Mulverhill in Annals of Forest Science, Vol 76 n° 3 (September 2019)
[article]
Titre : The utility of terrestrial photogrammetry for assessment of tree volume and taper in boreal mixedwood forests Type de document : Article/Communication Auteurs : Christopher Mulverhill, Auteur ; Nicholas C. Coops, Auteur ; Piotr Tompalski, Auteur ; Christopher W. Bater, Auteur ; Adam R. Dick, Auteur Année de publication : 2019 Article en page(s) : pp 76 - 83 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] Abies balsamea
[Termes IGN] Alberta (Canada)
[Termes IGN] allométrie
[Termes IGN] betula papyrifera var. papyrifera
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] diamètre des arbres
[Termes IGN] données dendrométriques
[Termes IGN] forêt boréale
[Termes IGN] hauteur des arbres
[Termes IGN] image terrestre
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] peuplement mélangé
[Termes IGN] photogrammétrie terrestre
[Termes IGN] Picea glauca
[Termes IGN] Picea mariana
[Termes IGN] Pinus contorta
[Termes IGN] Populus tremuloides
[Termes IGN] semis de points
[Termes IGN] volume en boisRésumé : (auteur) Key Message: This study showed that digital terrestrial photogrammetry is able to produce accurate estimates of stem volume and diameter across a range of species and tree sizes that showed strong correspondence when compared with traditional inventory techniques. This paper demonstrates the utility of the technology for characterizing trees in complex habitats such as boreal mixedwood forests.
Context: Accurate knowledge of tree stem taper and volume are key components of forest inventories to manage and study forest resources. Recent developments have seen the increasing use of ground-based point clouds, including from digital terrestrial photogrammetry (DTP), to provide accurate estimates of these key forest attributes.
Aims: In this study, we evaluated the utility of DTP based on a small set of photos (12 per tree) for estimating stem volume and taper on a set of 15 trees from 6 different species (Populus tremuloides, Picea glauca, Pinus contorta latifolia, Betula papyrifera, Picea mariana, Abies balsamea) in a boreal mixedwood forest in Alberta, Canada.
Methods: We constructed accurate photogrammetric point clouds and derived taper and volume from three point cloud–based methods, which were then compared with estimates from conventional, field-based measurements. All methods were evaluated for their accuracy based on field-measured taper and volume of felled trees.
Results: Of the methods tested, we found that the point cloud–derived diameters in a taper curve matching approach performed the best at estimating diameters at the lowest parts of the stem ( 50% of total height). Using the field-measured DBH and height as inputs to calculate stem volume yielded the most accurate predictions; however, these were not significantly different from the best point cloud-based estimates.
Conclusion: The methodology confirmed that using a small set of photographs provided accurate estimates of individual tree DBH, taper, and volume across a range of species and size gradients (10.8–40.4 cm DBH).Numéro de notice : A2019-303 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-019-0852-9 Date de publication en ligne : 08/08/2019 En ligne : https://doi.org/10.1007/s13595-019-0852-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93226
in Annals of Forest Science > Vol 76 n° 3 (September 2019) . - pp 76 - 83[article]Effet de la diversité des essences sur la hauteur dominante / Patrick Vallet in Rendez-vous techniques, n° 57 (hiver 2018)
[article]
Titre : Effet de la diversité des essences sur la hauteur dominante Type de document : Article/Communication Auteurs : Patrick Vallet, Auteur ; Thomas Pérot, Auteur Année de publication : 2019 Article en page(s) : pp 3 - 10 Note générale : bibliographie Langues : Français (fre) Descripteur : [Termes IGN] croissance des arbres
[Termes IGN] peuplement mélangé
[Termes IGN] productivité
[Vedettes matières IGN] SylvicultureRésumé : (éditeur) L’étude du fonctionnement des peuplements mélangés n’est pas près de s’épuiser. En ce qui concerne l’effet du mélange sur la productivité, les travaux ont surtout porté sur la croissance radiale ou en surface terrière. Mais la productivité dépend aussi de l’influence du mélange sur la croissance en hauteur, plus difficile à appréhender : les deux effets sont-ils de même ampleur ? Vont-ils dans le même sens ? Quels sont les mécanismes ? Méthode d’étude et premières réponses. Numéro de notice : A2018-671 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95557
in Rendez-vous techniques > n° 57 (hiver 2018) . - pp 3 - 10[article]Exemplaires(1)
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Effet de la diversité des essences sur la hauteur dominante - pdf éditeurAdobe Acrobat PDF Climate change and mixed forests: how do altered survival probabilities impact economically desirable species proportions of Norway spruce and European beech? / Carola Paul in Annals of Forest Science, vol 76 n° 1 (March 2019)
[article]
Titre : Climate change and mixed forests: how do altered survival probabilities impact economically desirable species proportions of Norway spruce and European beech? Type de document : Article/Communication Auteurs : Carola Paul, Auteur ; Susanne Brandl, Auteur ; Stefan Friedrich, Auteur ; Wolfgang Falk, Auteur ; Fabian Härtl, Auteur ; Thomas Knoke, Auteur Année de publication : 2019 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Allemagne
[Termes IGN] aménagement forestier
[Termes IGN] analyse de survie
[Termes IGN] biodiversité végétale
[Termes IGN] changement climatique
[Termes IGN] Fagus sylvatica
[Termes IGN] gestion forestière durable
[Termes IGN] peuplement mélangé
[Termes IGN] Picea abies
[Termes IGN] reboisement
[Termes IGN] régénération (sylviculture)
[Termes IGN] restauration écologique
[Vedettes matières IGN] Economie forestièreRésumé : (auteur) Context : Climate change is expected to increase natural hazards in European forests. Uncertainty in expected tree mortality and resulting potential economic consequences complicate regeneration decisions.
Aims : This study aims to analyze the economic consequences of altered survival probabilities for mixing Norway spruce (Picea abies L. Karst.) and European beech (Fagus sylvatica L.) under different climate change scenarios. We investigate whether management strategies such as species selection and type of mixture (mixed stands vs. block mixture) could mitigate adverse financial effects of climate change.
Methods : The bio-economic modelling approach combines a parametric survival model with modern portfolio theory. We estimate the economically optimal species mix under climate change, accounting for the biophysical and economic effects of tree mixtures. The approach is demonstrated using an example from Southeast Germany.
Results : The optimal tree species mixtures under simulated climate change effects could buffer but not completely mitigate undesirable economic consequences. Even under optimally mixed forest stands, the risk-adjusted economic value decreased by 28%. Mixed stands economically outperform block mixtures for all climate scenarios.
Conclusion : Our results underline the importance of mixed stands to mitigate the economic consequences of climate change. Mechanistic bio-economic models help to understand consequences of uncertain input variables and to design purposeful adaptation strategies.Numéro de notice : A2019-041 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-018-0793-8 Date de publication en ligne : 08/02/2019 En ligne : https://doi.org/10.1007/s13595-018-0793-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92039
in Annals of Forest Science > vol 76 n° 1 (March 2019)[article]Single-image photogrammetry for deriving tree architectural traits in mature forest stands: a comparison with terrestrial laser scanning / Kamil Kędra in Annals of Forest Science, vol 76 n° 1 (March 2019)
[article]
Titre : Single-image photogrammetry for deriving tree architectural traits in mature forest stands: a comparison with terrestrial laser scanning Type de document : Article/Communication Auteurs : Kamil Kędra, Auteur ; Ignacio Barbeito, Auteur ; Mathieu Dassot , Auteur ; Patrick Vallet, Auteur ; Anna Gazda, Auteur Année de publication : 2019 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] allométrie
[Termes IGN] analyse comparative
[Termes IGN] coefficient de corrélation
[Termes IGN] détection d'arbres
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] diamètre des arbres
[Termes IGN] forêt tempérée
[Termes IGN] hauteur des arbres
[Termes IGN] houppier
[Termes IGN] image isolée
[Termes IGN] Orléans, forêt domaniale d' (Loiret)
[Termes IGN] peuplement forestier
[Termes IGN] peuplement mélangé
[Termes IGN] Pinus sylvestris
[Termes IGN] Quercus (genre)
[Termes IGN] télémétrie laser terrestreRésumé : (auteur) Key message : We compared two methods for detailed individual tree measurements: single image photogrammetry (SIP), a simplified, low-cost method, and the state-of-the-art terrestrial laser scanning (TLS). Our results provide evidence that SIP can be successfully applied to obtain accurate tree architectural traits in mature forests.
Context : Tree crown variables are necessary in forest modelling; however, they are time consuming to measure directly, and they are measured in many different ways. We compare two methods to obtain crown variables: laser-based and image-based. TLS is an advanced technology for three-dimensional data acquisition; SIP is a simplified, low-cost method.
Aims : To elucidate differences between the methods, and validate SIP accuracy and usefulness for forest research, we investigated if (1) SIP and TLS measurements are in agreement in terms of the most widely used tree characteristics; (2) differences between the SIP traits and their TLS counterparts are constant throughout tree density and species composition; (3) tree architectural traits obtained with SIP explain differences in laser-based crown projection area (CPA), under different forest densities and stand compositions; and (4) CPA modelled with SIP variables is more accurate than CPA obtained with stem diameter-based allometric models. We also examined the correspondence between local tree densities extracted from images and from field measurements.
Methods : We compared TLS and SIP in a temperate pure sessile oak and mixed with Scots pine stands, in the Orléans Forest, France. Standard major axis regression was used to establish relations between laser-based and image-based tree height and diameter at breast height. Four SIP-derived traits were compared between the levels of stand density and species composition with a t test, in terms of deviations and biases to their TLS counterparts. We created a set of linear and linear mixed models (LMMs) of CPATLS, with SIP variables. Both laser-based and image-based stem diameters were used to estimate CPA with the published allometric equations; the results were then compared with the best predictive LMM, in terms of similarity with CPATLS measurement. Local tree density extracted from images was compared with field measurements in terms of basic statistics and correlation.
Results : Tree height and diameter at breast height were reliably represented by SIP (Pearson correlation coefficients r = 0.92 and 0.97, respectively). SIP measurements were affected by the stand composition factor; tree height attained higher mean absolute deviation (1.09 m) in mixed stands, compared to TLS, than in pure stands (0.66 m); crown width was more negatively biased in mixed stands (− 0.79 m), than in pure stands (− 0.05 m); and diameter at breast height and crown asymmetry were found unaffected. Crown width and mean branch angle were key SIP explanatory variables to predict CPATLS. The model was approximately 2-fold more accurate than the CPA allometric estimations with both laser-based and image-based stem diameters. SIP-derived local tree density was similar to the field-measured density in terms of mean and standard deviation (9.6 (3.5) and 9.4 (3.6) trees per plot, respectively); the correlation between both density measures was significantly positive (r = 0.76).
Conclusion : SIP-derived variables, such as crown width, mean branch angle, branch thickness, and crown asymmetry, were useful to explain tree architectural differences under different densities and stand compositions and may be implemented in many forest research applications. SIP may also provide a coarse measure of local competition, in terms of number of neighbouring trees. Our study provides the first test in mature forest stands, for SIP compared with TLS.Numéro de notice : A2019-044 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-018-0783-x Date de publication en ligne : 07/01/2019 En ligne : https://doi.org/10.1007/s13595-018-0783-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92050
in Annals of Forest Science > vol 76 n° 1 (March 2019)[article]Species mixing effects on forest productivity : A case study at stand-, species- and tree-level in the Netherlands / Huicui Lu in Forests, vol 9 n° 11 (November 2018)PermalinkSilvicultural climatic turning point for European beech and sessile oak in Western Europe derived from national forest inventories / Klara Dolos in Forest ecology and management, vol 373 (1 August 2016)PermalinkMicrowave 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)PermalinkVariation in irradiance, soil features and regeneration patterns in experimental forest canopy gaps / Urša Vilhar in Annals of Forest Science, vol 72 n° 2 (March - april 2015)PermalinkBases d'une gestion durable des forêts mélangées : résultats d'un projet de recherche mené sur quatre ans / Thomas Cordonnier in Rendez-vous techniques, n° 27-28 (hiver - printemps 2010)PermalinkComment estimer la lumière dans le sous-bois forestier à partir des caractéristiques dendrométriques des peuplements ? / Philippe Balandier ; André Marquier ; Sandrine Perret ; Catherine Collet ; Benoît Courbaud in Rendez-vous techniques, n° 27-28 (hiver - printemps 2010)PermalinkDynamique des forêts mélangées sur le Mont-Ventoux : effets de l'altitude et de la gestion / Philippe Dreyfus in Rendez-vous techniques, n° 27-28 (hiver - printemps 2010)PermalinkInstaller des semis de chênes dans les pinèdes à pin d’Alep en phase de renouvellement / Bernard Prévosto in Forêt méditerranéenne, vol 31 n° 1 (mars 2010)PermalinkModélisation de la croissance des peuplements mélangés chêne-pin : des enseignements importants pour la sylviculture de ces peuplements / Christine Micheneau ; Christine Deleuze-Brezins ; Jean-François Dhôte ; Myriam Legay in Rendez-vous techniques, n° 27-28 (hiver - printemps 2010)PermalinkResponse to canopy opening does not act as a filter to Fagus sylvatica and Acer sp. advance regeneration in a mixed temperate forest / Blandine Caquet in Annals of Forest Science, vol 67 n° 1 (January-February 2010)PermalinkHybridization between Quercus robur and Q. petraea in a mixed oak stand in Denmark / J. Jensen in Annals of Forest Science, Vol 66 n° 7 (October - November 2009)PermalinkComparing volume growth in pure and mixed stands of Pinus sylvestris and Quercus pyrenaica / Miren del Río in Annals of Forest Science, Vol 66 n° 5 (July - August 2009)PermalinkNatural stand structures, disturbance regimes and successional dynamics in the Eurasian boreal forests: a review with special reference to Russian studies / Ekaterina Shorohova in Annals of Forest Science, Vol 66 n° 2 (march 2009)PermalinkLeaf water status and stem xylem flux in relation to soil drought in five temperate broad-leaved tree species with contrasting water use strategies / Paul Köcher in Annals of Forest Science, Vol 66 n° 1 (January - February 2009)PermalinkWhy and where do adult trees die in a young secondary temperate forest? The role of neighbourhood / José Miguel Olano in Annals of Forest Science, Vol 66 n° 1 (January - February 2009)PermalinkGérer l'alisier dans les peuplements mélangés / Georg Josef Wilhelm in Forêt entreprise, n° 184 (2009/1)PermalinkAménagement et aide à la décision : restitution de l'atelier 2a / Christine Deleuze in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkConduite de peuplements mélangés en forêts de montagne : exemple d'une collaboration chercheurs-gestionnaires / Xavier Gauquelin in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkDynamiques du Sapin, du Hêtre et des Pins d'ans l'arrière-pays méditerranéen : de la modélisation à l'aide à la gestion / Philippe Dreyfus in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkEtudier et comprendre une forêt mélangée, une tâche difficile : réflexions basées sur le développement des recherches en forêts boréale, tempérée et tropicale / Alain Franc in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkForêt mélangée et maintien de la diversité génétique / François Lefèvre in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkLes forêts mélangées en France métropolitaine : Caractérisation à partir des résultats de l'Inventaire forestier national / François Morneau in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkDes forêts mélangées pour composer avec les changements climatiques / Myriam Legay in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkLe forum d'échange des ateliers REGEFOR 2007 : une diversité d'activités dédiées aux forêts hétérogènes / Sandrine Landeau in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkLes interactions entre espèces d'arbres dans les mélanges illustrées par le cas des feuillus et des conifères dans les forêts de montagne / Richard Michalet in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkLe mélange d'essences est-il favorable à la diversité végétale en forêt ? / Stéphane Barbier in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkLes peuplements forestiers mélangés. Introduction aux ateliers Recherche et gestion forestière (REGEFOR) 2007 / Sandrine Landeau in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkLes peuplements mélangés : enjeux et interrogations des gestionnaires / Thierry Sardin in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkPour alléger le suivi des plantations : le mélange avec des essences secondaires / Jacques Becquey in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkA propos des plantations mélangées de Chêne sessile, Pin laricio de Corse et Pin sylvestre / Jean-Paul Nebout in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkQuels modèles de croissance pour les peuplements mélangés ? Exemple du mélange Chêne sessile - Pin sylvestre / Thomas Pérot in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkRésistance aux vents forts des peuplements forestiers, et notamment des mélanges d'espèces / Francis Colin in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkLe risque sanitaire dans les forêts mélangées / Hervé Jactel in Revue forestière française, vol 60 n° 2 (mars - avril 2008)Permalink