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How do trees respond to species mixing in experimental compared to observational studies? / Stephan Kambach in Ecology and evolution, vol 9 n° 19 (October 2019)
[article]
Titre : How do trees respond to species mixing in experimental compared to observational studies? Type de document : Article/Communication Auteurs : Stephan Kambach, Auteur ; Eric Allan, Auteur ; Simon Bilodeau‐Gauthier, Auteur ; David A. Coomes, Auteur ; Josephine Haase, Auteur ; Tommaso Jucker, Auteur ; Georges Kunstler, Auteur ; Sandra Müller, Auteur ; Charles Nock, Auteur ; Alain Paquette, Auteur ; Fons van der plas, Auteur ; Sophie Ratcliffe, Auteur ; Fabian Roger, Auteur ; Paloma Ruiz-Benito, Auteur ; Michael Scherer‐Lorenzen, Auteur ; Harald Auge, Auteur ; Olivier Bouriaud , Auteur ; et al., Auteur Année de publication : 2019 Projets : 3-projet - voir note / Article en page(s) : pp 11254 - 11265 Note générale : bibliographie
This paper is a joint effort of the working group sFundivEurope kindly supported by sDiv, the Synthesis Centre of the German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, funded by the German Research Foundation (FZT 118). The FunDivEUROPE project received funding from the European Union's Seventh Programme (FP7/2007–2013) under grant agreement No. 26517.Langues : Anglais (eng) Descripteur : [Termes IGN] biodiversité
[Termes IGN] croissance des arbres
[Termes IGN] diamètre des arbres
[Termes IGN] forêt de production
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] peuplement mélangé
[Termes IGN] productivité
[Vedettes matières IGN] SylvicultureRésumé : (auteur) For decades, ecologists have investigated the effects of tree species diversity on tree productivity at different scales and with different approaches ranging from observational to experimental study designs. Using data from five European national forest inventories (16,773 plots), six tree species diversity experiments (584 plots), and six networks of comparative plots (169 plots), we tested whether tree species growth responses to species mixing are consistent and therefore transferrable between those different research approaches. Our results confirm the general positive effect of tree species mixing on species growth (16% on average) but we found no consistency in species‐specific responses to mixing between any of the three approaches, even after restricting comparisons to only those plots that shared similar mixtures compositions and forest types. These findings highlight the necessity to consider results from different research approaches when selecting species mixtures that should maximize positive forest biodiversity and functioning relationships. Numéro de notice : A2019-616 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1002/ece3.5627 Date de publication en ligne : 10/09/2019 En ligne : https://doi.org/10.1002/ece3.5627 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95342
in Ecology and evolution > vol 9 n° 19 (October 2019) . - pp 11254 - 11265[article]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 Réflexions d’une paysagiste sur la progression des boisements spontanés dans les Alpes et les Pyrénées / Françoise Copin in Revue forestière française, vol 71 n° 4-5 (2019)
[article]
Titre : Réflexions d’une paysagiste sur la progression des boisements spontanés dans les Alpes et les Pyrénées Type de document : Article/Communication Auteurs : Françoise Copin, Auteur Année de publication : 2019 Article en page(s) : pp 423 - 436 Note générale : bibliographie Langues : Français (fre) Descripteur : [Termes IGN] Alpes (France)
[Termes IGN] aménagement forestier
[Termes IGN] boisement naturel
[Termes IGN] carte forestière
[Termes IGN] feuillu
[Termes IGN] forêt
[Termes IGN] forêt alpestre
[Termes IGN] histoire
[Termes IGN] Moyen-Age
[Termes IGN] Piémont (Italie)
[Termes IGN] Pinophyta
[Termes IGN] Pyrénées (montagne)
[Termes IGN] typologie forestière
[Vedettes matières IGN] SylvicultureRésumé : (auteur) Dans de nombreuses vallées des Alpes et des Pyrénées, la forêt est revenue sur des lieux autrefois habités, cultivés ou pâturés. Elle incarne le retour d’un sauvage qui s’inscrit en creux d’activités domestiques qui per- sistent (alpages, fonds de vallées). Deux hauts de vallées se rencontrant au col de Tende serviront d’exemple pour illustrer l’évolution des regards sur la forêt et proposer des pistes d’un projet de paysage cherchant l’équilibre entre des lieux domestiques et des espaces sauvages. Après cette approche, issue de son travail de fin d’études à l’École de la Nature et du Paysage de Blois, l’auteur propose un éclairage plus sociologique nourri par une enquête dans la vallée du Vicdessos. Des communes du Parc naturel régional des Pyrénées ariégeoises y conduisent des ouvertures paysagères en réaction à la progression du couvert forestier autour des villages. Ces interventions très localisées répondent à des enjeux écologiques de restauration de milieux ouverts, mais témoignent aussi et surtout d’un besoin de contrôle des habitats forestiers et de la faune asso- ciée. Dans les deux cas, le chantier est ouvert pour imaginer de nouveaux liens aux boisements spontanés. Numéro de notice : A2019-648 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.4267/2042/70824 En ligne : https://doi.org/10.4267/2042/70824 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97019
in Revue forestière française > vol 71 n° 4-5 (2019) . - pp 423 - 436[article]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]Two contemporary and efficient two-stage sampling methods for estimating the volume of forest stands: a brief overview and unified mathematical description / Aristeidis Georgakis in Open journal of forestry, vol 9 n° 3 (July 2019)
[article]
Titre : Two contemporary and efficient two-stage sampling methods for estimating the volume of forest stands: a brief overview and unified mathematical description Type de document : Article/Communication Auteurs : Aristeidis Georgakis, Auteur ; Georgios Stamatellos, Auteur Année de publication : 2019 Article en page(s) : pp 241 - 254 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] échantillonnage
[Termes IGN] estimation statistique
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] peuplement forestier
[Termes IGN] surface terrière
[Termes IGN] volume en bois
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Big Basal Area Factor (Big BAF) and Point-3P are two-stage sampling methods. In the first stage the sampling units, in both methods, are Bitterlich points where the selection of the trees is proportional to their basal area. In the second stage, sampling units are trees which are a subset of the first stage trees. In the Big BAF method, the probability of selecting trees in the second stage is made proportional to the two BAFs’ ratio, with a basal area factor larger than that of the first stage. In the Point-3P method the probability of selecting trees, in the second stage, is based on the height prediction and use of a specific random number table. Estimates of the forest stands’ volume and their sampling errors are based on the theory of the product of two random variables. The increasing error in the second stage is small, but the total cost of measuring the trees is much smaller than simply using the first stage, with all the trees measured. In general, the two sampling methods are modern and cost-effective approaches that can be applied in forest stand inventories for forest management purposes and are receiving the growing interest of researchers in the current decade. Numéro de notice : A2019-381 Affiliation des auteurs : non IGN Thématique : FORET/MATHEMATIQUE Nature : Article DOI : 10.4236/ojf.2019.93013 En ligne : https://doi.org/10.4236/ojf.2019.93013 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93460
in Open journal of forestry > vol 9 n° 3 (July 2019) . - pp 241 - 254[article]A general method for the classification of forest stands using species composition and vertical and horizontal structure / Miquel De Cáceres in Annals of Forest Science, vol 76 n° 2 (June 2019)PermalinkGenetic diversity and structure of Silver fir (Abies alba Mill.) at the south-eastern limit of its distribution range / Maria Teodosiu in Annals of forest research, vol 62 n° 2 (June - December 2019)PermalinkEstimating architecture-based metabolic scaling exponents of tropical trees using terrestrial LiDAR and 3D modelling / Alvaro Lau in Forest ecology and management, vol 439 (1 May 2019)PermalinkModel-based investigation on the effects of spatial evenness, and size selection in thinning of Picea abies stands / Peter Fransson in Scandinavian journal of forest research, vol 34 n° 3 (May 2019)PermalinkEffet de la diversité des essences sur la hauteur dominante / Patrick Vallet in Rendez-vous techniques, n° 57 (hiver 2018)PermalinkClimate 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)PermalinkSingle-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)PermalinkEffect of forest structure on stand productivity in Central European forests depends on developmental stage and tree species diversity / Laura Zeller in Forest ecology and management, vol 434 (28 February 2019)PermalinkUsing LiDAR to develop high-resolution reference models of forest structure and spatial pattern / Haley L. Wiggins in Forest ecology and management, vol 434 (28 February 2019)PermalinkLeaf area density from airborne LiDAR: Comparing sensors and resolutions in a temperate broadleaf forest ecosystem / Aaron G. Kamoske in Forest ecology and management, vol 433 (15 February 2019)Permalink