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Determining tree height and crown diameter from high-resolution UAV imagery / Dimitrios Panagiotidis in International Journal of Remote Sensing IJRS, vol 38 n° 8-10 (April 2017)
[article]
Titre : Determining tree height and crown diameter from high-resolution UAV imagery Type de document : Article/Communication Auteurs : Dimitrios Panagiotidis, Auteur ; Azadeh Abdollahnejad, Auteur ; Peter Surový, Auteur ; Vasco Chiteculo, Auteur Année de publication : 2017 Article en page(s) : pp 2392 - 2410 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Betula pendula
[Termes IGN] hauteur des arbres
[Termes IGN] houppier
[Termes IGN] image aérienne
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] Larix decidua
[Termes IGN] modèle numérique de surface de la canopée
[Termes IGN] Picea abies
[Termes IGN] Pinus sylvestris
[Termes IGN] reconstruction 3D
[Termes IGN] séquence d'images
[Termes IGN] structure-from-motion
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Advances in computer vision and the parallel development of unmanned aerial vehicles (UAVs) allow for the extensive use of UAV in forest inventory and in indirect measurements of tree features. We used UAV-sensed high-resolution imagery through photogrammetry and Structure from Motion (SfM) to estimate tree heights and crown diameters. We reconstructed 3D structures from 2D image sequences for two study areas (25 × 25 m). Species composition for Plot 1 included Norway spruce (Picea abies L.) together with European larch (Larix decidua Mill.) and Scots pine (Pinus sylvestris L.), whereas Plot 2 was mainly Norway spruce and Scots pine together with scattered individuals of European larch and Silver birch (Betula pendula Roth.). The involved workflow used canopy height models (CHMs) for the extraction of height, the smoothing of raster images for the determination of the local maxima, and Inverse Watershed Segmentation (IWS) for the estimation of the crown diameters with the help of a geographical information system (GIS). Finally, we validated the accuracies of the two methods by comparing the UAV results with ground measurements. The results showed higher agreement between field and remote-sensed data for heights than for crown diameters based on RMSE%, which were in the range 11.42–12.62 for height and 14.29–18.56 for crown diameter. Overall, the accuracy of the results was acceptable and showed that the methods were feasible for detecting tree heights and crown diameter. Numéro de notice : A2017-683 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431161.2016.1264028 En ligne : http://dx.doi.org/10.1080/01431161.2016.1264028 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=87246
in International Journal of Remote Sensing IJRS > vol 38 n° 8-10 (April 2017) . - pp 2392 - 2410[article]Mapping forest attributes using data from stereophotogrammetry of aerial images and field data from the national forest inventory / Jonas Bohlin in Silva fennica, vol 51 n° 2 (2017)
[article]
Titre : Mapping forest attributes using data from stereophotogrammetry of aerial images and field data from the national forest inventory Type de document : Article/Communication Auteurs : Jonas Bohlin, Auteur ; Inka Bohlin, Auteur ; Jonas Jonzén, Auteur ; Mats Nilsson, Auteur Année de publication : 2017 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Betula (genre)
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] image aérienne
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] Picea abies
[Termes IGN] Pinus sylvestris
[Termes IGN] régression linéaire
[Termes IGN] semis de points
[Termes IGN] Suède
[Termes IGN] surface terrière
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Exploring the possibility to produce nation-wide forest attribute maps using stereophotogrammetry of aerial images, the national terrain model and data from the National Forest Inventory (NFI). The study areas are four image acquisition blocks in mid- and south Sweden. Regression models were developed and applied to 12.5 m × 12.5 m raster cells for each block and validation was done with an independent dataset of forest stands. Model performance was compared for eight different forest types separately and the accuracies between forest types clearly differs for both image- and LiDAR methods, but between methods the difference in accuracy is small at plot level. At stand level, the root mean square error in percent of the mean (RMSE%) were ranging: from 7.7% to 10.5% for mean height; from 12.0% to 17.8% for mean diameter; from 21.8% to 22.8% for stem volume; and from 17.7% to 21.1% for basal area. This study clearly shows that aerial images from the national image program together with field sample plots from the NFI can be used for large area forest attribute mapping. Numéro de notice : A2017-648 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.14214/sf.2021 En ligne : https://doi.org/10.14214/sf.2021 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=87007
in Silva fennica > vol 51 n° 2 (2017)[article]Dynamics of fungal community composition, decomposition and resulting deadwood properties in logs of Fagus sylvatica, Picea abies and Pinus sylvestris / Tobias Arnstadt in Forest ecology and management, vol 382 (15 December 2016)
[article]
Titre : Dynamics of fungal community composition, decomposition and resulting deadwood properties in logs of Fagus sylvatica, Picea abies and Pinus sylvestris Type de document : Article/Communication Auteurs : Tobias Arnstadt, Auteur ; Björn Hoppe, Auteur ; Harald Kellner, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 129 - 142 Langues : Anglais (eng) Descripteur : [Termes IGN] Allemagne
[Termes IGN] bois mort
[Termes IGN] Fagus sylvatica
[Termes IGN] Fungi
[Termes IGN] habitat d'espèce
[Termes IGN] habitat forestier
[Termes IGN] lignine
[Termes IGN] Picea abies
[Termes IGN] Pinus sylvestris
[Termes IGN] richesse floristique
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) In forest ecosystems, deadwood is an important component that provides habitat and contributes to nutrient cycles, as well as to carbon and water storage. The change of wood constituents, nutrients and microbial species richness in the field over the whole time of decomposition has only rarely been studied, in particular not in relation to oxidative enzyme activities (mediating lignin degradation) and different forest management regimes.
To describe wood decomposition, we selected coarse woody debris (CWD) in form of 197 logs of Fagus sylvatica, Picea abies and Pinus sylvestris in forests with different management regimes across three regions in Germany. They were sampled and analyzed for wood density, water content, wood constituents (Klason and acid-soluble lignin, organic extractives, water-soluble lignin fragments), carbon, nitrogen and metals (Al, Ca, Cu, K, Mg, Mn and Zn). Furthermore, the activities of oxidative enzymes like laccase, manganese peroxidase, and general peroxidase were measured. Since filamentous fungi (Basidiomycota, Ascomycota) are the major biological agents of wood decomposition, fungal species richness based on sporocarps and molecular fingerprints was recorded.
Higher forest management intensity had a negative effect on deadwood volume and in consequence on fungal species richness (sporocarps), but hardly to other analyzed variables. Furthermore, there were significant differences between the tree species for the concentrations of wood constituents and most nutrients as well as the activities of oxidative enzymes, although their course during decomposition was mostly similar among the tree species. We found that molecular species richness increased with the period of decomposition in contrast to the number of fruiting species, which was highest in the intermediate stage of decomposition. Both types of species richness increased with increasing volume of the CWD logs. Regarding the entire period of decomposition, white-rot fungi (WRF), based on identification of sporocarps, were the most abundant group of wood-decaying fungi in all three tree species. This corresponds well with the overall presence of laccase and peroxidases and the concomitant substantial loss of lignin, which points to the importance of these enzymes in deadwood decomposition. We found a continuous decomposition and decline of volume-related concentrations in wood constituents and nutrients with time of decomposition. Contrary to volume-related concentrations, the concentrations related to dry mass frequently increased.Numéro de notice : A2016-765 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1016/j.foreco.2016.10.004 En ligne : http://dx.doi.org/10.1016/j.foreco.2016.10.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82401
in Forest ecology and management > vol 382 (15 December 2016) . - pp 129 - 142[article]Tree diversity effect on dominant height in temperate forest / Patrick Vallet in Forest ecology and management, vol 381 (1 December 2016)
[article]
Titre : Tree diversity effect on dominant height in temperate forest Type de document : Article/Communication Auteurs : Patrick Vallet, Auteur ; Thomas Pérot, Auteur Année de publication : 2016 Article en page(s) : pp 106 - 114 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies alba
[Termes IGN] biodiversité végétale
[Termes IGN] Fagus sylvatica
[Termes IGN] forêt tempérée
[Termes IGN] hauteur des arbres
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] peuplement forestier
[Termes IGN] Picea abies
[Termes IGN] Pinus sylvestris
[Termes IGN] Quercus sessiliflora
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) For forest ecosystems, studies dealing with diversity-productivity relationships are often based on diameter increment observations. Studying how height growth is affected by species interactions can provide new insights on this issue. We studied the mixture effect on dominant height growth in order to answer two questions. Do species interactions in mixed forest modify the dominant height growth of species? Does the diversity effect on diameter found in previous studies correspond to actual overyielding, or rather to an effect on allocation of growth between diameter and height?
We used the French National Forest Inventory (NFI) data to model the mixture effect on dominant height. We included biophysical factors in the models to compare the dominant height of mixed and monospecific stands, all other parameters being equal. We studied five target species – Quercus petraea (Matt.) Liebl., Fagus sylvatica L., Picea abies (L.) Karst., Abies alba Mill., and Pinus sylvestris L. – in association with sixteen other species.
Mixture effects on dominant height were weak, though often significant. They were either positive or negative according to species association. We showed that mixture effect on dominant height corresponds to a leveling process between species: the taller one limits its growth while the smaller one’s growth increases. Furthermore, most of the time, mixture effects on dominant height are in the same direction as those found on diameter, though with a lower magnitude. Our results confirm that tree diversity results in overyielding rather than in a different allocation of volume between the parts of the tree.Numéro de notice : A2016-703 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1016/j.foreco.2016.09.024 En ligne : http://dx.doi.org/10.1016/j.foreco.2016.09.024 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82072
in Forest ecology and management > vol 381 (1 December 2016) . - pp 106 - 114[article]Automatic segment-level tree species recognition using high resolution aerial winter imagery / Anton Kuzmin in European journal of remote sensing, vol 49 n° 1 (2016)
[article]
Titre : Automatic segment-level tree species recognition using high resolution aerial winter imagery Type de document : Article/Communication Auteurs : Anton Kuzmin, Auteur ; Lauri Korhonen, Auteur ; Terhikki Manninen, Auteur ; Matti Maltamo, Auteur Année de publication : 2016 Article en page(s) : pp 239 - 259 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse d'image orientée objet
[Termes IGN] analyse discriminante
[Termes IGN] betula pubescens
[Termes IGN] composition floristique
[Termes IGN] forêt boréale
[Termes IGN] hélicoptère
[Termes IGN] hiver
[Termes IGN] image à ultra haute résolution
[Termes IGN] image aérienne
[Termes IGN] neige
[Termes IGN] Picea abies
[Termes IGN] Pinus sylvestrisRésumé : (auteur) Our objective was to automatically recognize the species composition of a boreal forest from high-resolution airborne winter imagery. The forest floor was covered by snow so that the contrast between the crowns and the background was maximized. The images were taken from a helicopter flying at low altitude so that fine details of the canopy structure could be distinguished. Segments created by an object-oriented image processing were used as a basis for a linear discriminant analysis, which aimed at separating the three dominant tree species occurring in the area: Scots pine, Norway spruce, and downy birch. In a cross validation, the classification showed an overall accuracy of 81.9%, and a kappa coefficient of 0.73. Numéro de notice : A2016-831 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.5721/EuJRS20164914 En ligne : http://dx.doi.org/10.5721/EuJRS20164914 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82714
in European journal of remote sensing > vol 49 n° 1 (2016) . - pp 239 - 259[article]Dead wood availability in managed Swedish forests – Policy outcomes and implications for biodiversity / Bengt Gunnar Jonsson in Forest ecology and management, vol 376 (15 September 2016)PermalinkTree species identity mediates mechanisms of top soil carbon sequestration in a Norway spruce and European beech mixed forest / Enrique Andivia in Annals of Forest Science, vol 73 n° 2 (June 2016)PermalinkEstimating over- and understorey canopy density of temperate mixed stands by airborne LiDAR data / Hooman Latifi in Forestry, an international journal of forest research, vol 89 n° 1 (January 2016)PermalinkLa forêt en chiffres et en cartes / Institut national de l'information géographique et forestière (2012 -) (2016)PermalinkComparison of linear mixed effects model and generalized model of the tree height-diameter relationship / Z. Adamec in Journal of forest science, vol 61 n° 10 (October 2015)PermalinkVariables related to nitrogen deposition improve defoliation models for European forests / Marco Ferretti in Annals of Forest Science, vol 72 n° 7 (October 2015)PermalinkFORESTIMATOR : un plugin QGIS d'estimation de la hauteur dominante et du site index de peuplements résineux à partir de Lidar aérien / Laurent Dedry in Revue Française de Photogrammétrie et de Télédétection, n° 211 - 212 (juillet - décembre 2015)PermalinkSite suitability for tree species: Is there a positive relation between a tree species’ occurrence and its growth? / Klara Dolos in European Journal of Forest Research, vol 134 n° 4 (July 2015)PermalinkDeveloping predictive models of wind damage in Austrian forests / Ferenc Pasztor in Annals of Forest Science, vol 72 n° 3 (May 2015)PermalinkDo competition-density rule and self-thinning rule agree? / Sonja Vospernik in Annals of Forest Science, vol 72 n° 3 (May 2015)Permalink