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GCPs-free photogrammetry for estimating tree height and crown diameter in Arizona cypress plantation using UAV-mounted GNSS RTK / Morteza Pourreza in Forests, vol 13 n° 11 (November 2022)
[article]
Titre : GCPs-free photogrammetry for estimating tree height and crown diameter in Arizona cypress plantation using UAV-mounted GNSS RTK Type de document : Article/Communication Auteurs : Morteza Pourreza, Auteur ; Fardin Moradi, Auteur ; Mohammad Khosravi, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 1905 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] cupressus (genre)
[Termes IGN] diamètre des arbres
[Termes IGN] hauteur de vol
[Termes IGN] hauteur des arbres
[Termes IGN] image captée par drone
[Termes IGN] Iran
[Termes IGN] modèle numérique de surface de la canopée
[Termes IGN] point d'appui
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] structure-from-motionRésumé : (auteur) One of the main challenges of using unmanned aerial vehicles (UAVs) in forest data acquisition is the implementation of Ground Control Points (GCPs) as a mandatory step, which is sometimes impossible for inaccessible areas or within canopy closures. This study aimed to test the accuracy of a UAV-mounted GNSS RTK (real-time kinematic) system for calculating tree height and crown height without any GCPs. The study was conducted on a Cupressus arizonica (Greene., Arizona cypress) plantation on the Razi University Campus in Kermanshah, Iran. Arizona cypress is commonly planted as an ornamental tree. As it can tolerate harsh conditions, this species is highly appropriate for afforestation and reforestation projects. A total of 107 trees were subjected to field-measured dendrometric measurements (height and crown diameter). UAV data acquisition was performed at three altitudes of 25, 50, and 100 m using a local network RTK system (NRTK). The crown height model (CHM), derived from a digital surface model (DSM), was used to estimate tree height, and an inverse watershed segmentation (IWS) algorithm was used to estimate crown diameter. The results indicated that the means of tree height obtained from field measurements and UAV estimation were not significantly different, except for the mean values calculated at 100 m flight altitude. Additionally, the means of crown diameter reported from field measurements and UAV estimation at all flight altitudes were not statistically different. Root mean square error (RMSE Numéro de notice : A2022-838 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.3390/f13111905 Date de publication en ligne : 12/11/2022 En ligne : https://doi.org/10.3390/f13111905 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102039
in Forests > vol 13 n° 11 (November 2022) . - n° 1905[article]Automated detection of individual Juniper tree location and forest cover changes using Google Earth Engine / Sudeera Wickramarathna in Annals of forest research, vol 64 n° 1 (2021)
[article]
Titre : Automated detection of individual Juniper tree location and forest cover changes using Google Earth Engine Type de document : Article/Communication Auteurs : Sudeera Wickramarathna, Auteur ; Jamon Van Den Hoek, Auteur ; Bogdan Mihai Strimbu, Auteur Année de publication : 2021 Article en page(s) : pp 61 - 72 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] canopée
[Termes IGN] classification dirigée
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] couvert forestier
[Termes IGN] croissance des arbres
[Termes IGN] détection d'arbres
[Termes IGN] détection de changement
[Termes IGN] extraction de la végétation
[Termes IGN] Google Earth Engine
[Termes IGN] image à très haute résolution
[Termes IGN] image multibande
[Termes IGN] juniperus (genre)
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] Normalized Difference Water Index
[Termes IGN] Oregon (Etats-Unis)
[Termes IGN] réflectanceRésumé : (auteur) Tree detection is the first step in the appraisal of a forest, especially when the focus is monitoring the growth of tree canopy. The acquisition of annual very high-resolution aerial images by the National Agriculture Imagery Program (NAIP) and their accessibility through Google Earth Engine (GEE) supports the delineation of tree canopies and change over time in a cost and time-effective manner. The objectives of this study are to develop an automated method to detect the crowns of individual western Juniper (Juniperus occidentalis) trees and to assess the change of forest cover from multispectral 1-meter resolution NAIP images collected from 2009 to 2016, in Oregon, USA. The Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), and Ratio Vegetation Index (RVI), were calculated from the NAIP images, in addition to the red-green-blue-near infrared bands. To identify the most suitable approach for individual tree crown identification, we created two training datasets: one considering yearly images separately and one merging all images, irrespective of the year. We segmented individual tree crowns using a random forest algorithm implemented in GEE and seven rasters, namely the reflectance of four spectral bands as recorded by the NAIP images (i.e., the red-green-blue-near infrared) and three calculated indices (i.e., NDVI, NDWI, and RVI). We compared the estimated location of the trees, computed as the centroid of the crown, with the visually identified treetops, which were considered as validation locations. We found that tree location errors were smaller when years were analyzed individually than by merging the years. Measurements of completeness (74%), correctness (94%), and mean accuracy detection (82 %) show promising performance of the random forest algorithm in crown delineation, considering that only four original input bands were used for crown segmentation. The change in the calculated crown area for western juniper follows a sinusoidal curve, with a decrease from 2011 to 2012 and an increase from 2012 to 2014. The proposed approach has the potential to estimate individual tree locations and forest cover area dynamics at broad spatial scales using regularly collected airborne imagery with easy-to-implement methods. Numéro de notice : A2021-779 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.15287/afr.2020.2145 Date de publication en ligne : 28/06/2021 En ligne : https://doi.org/10.15287/afr.2020.2145 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98846
in Annals of forest research > vol 64 n° 1 (2021) . - pp 61 - 72[article]Analyzing the role of pulse density and voxelization parameters on full-waveform LiDAR-derived metrics / Pablo Crespo-Peremarch in ISPRS Journal of photogrammetry and remote sensing, vol 146 (December 2018)
[article]
Titre : Analyzing the role of pulse density and voxelization parameters on full-waveform LiDAR-derived metrics Type de document : Article/Communication Auteurs : Pablo Crespo-Peremarch, Auteur ; Luis Ángel Ruiz, Auteur ; Angel Balaguer-Beser, Auteur ; Javier Estornell, Auteur Année de publication : 2018 Article en page(s) : pp 453 - 464 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] Abies grandis
[Termes IGN] Acer macrophyllum
[Termes IGN] amplitude
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] étalonnage en vol
[Termes IGN] filtrage du bruit
[Termes IGN] forme d'onde pleine
[Termes IGN] impulsion laser
[Termes IGN] lidar à retour d'onde complète
[Termes IGN] Oregon (Etats-Unis)
[Termes IGN] prétraitement du signal
[Termes IGN] Pseudotsuga menziesii
[Termes IGN] Thuja plicata
[Termes IGN] Tsuga heterophylla
[Termes IGN] voxelRésumé : (auteur) LiDAR full-waveform (LFW) pulse density is not homogeneous along study areas due to overlap between contiguous flight stripes and, to a lesser extent, variations in height, velocity and altitude of the platform. As a result, LFW-derived metrics extracted at the same spot but at different pulse densities differ, which is called “side-lap effect”. Moreover, this effect is reflected in forest stand estimates, since they are predicted from LFW-derived metrics. This study was undertaken to analyze LFW-derived metric variations according to pulse density, voxel size and value assignation method in order to reduce the side-lap effect. Thirty LiDAR samples with a minimum density of 16 pulses.m−2 were selected from the testing area and randomly reduced to 2 pulses.m−2 with an interval of 1 pulse.m−2, then metrics were extracted and compared for each sample and pulse density at different voxel sizes and assignation values. Results show that LFW-derived metric variations as a function of pulse density follow a negative exponential model similar to the exponential semivariogram curve, increasing sharply until they reach a certain pulse density, where they become stable. This value represents the minimum pulse density (MPD) in the study area to optimally minimize the side-lap effect. This effect can also be reduced with pulse densities lower than the MPD modifying LFW parameters (i.e. voxel size and assignation value). Results show that LFW-derived metrics are not equally influenced by pulse density, such as number of peaks (NP) and ROUGHness of the outermost canopy (ROUGH) that may be discarded for further analyses at large voxel sizes, given that they are highly influenced by pulse density. In addition, side-lap effect can be reduced by either increasing pulse density or voxel size, or modifying the assignation value. In practice, this leads to a proper estimate of forest stand variables using LFW data. Numéro de notice : A2018-543 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2018.10.012 Date de publication en ligne : 05/11/2018 En ligne : https://doi.org/10.1016/j.isprsjprs.2018.10.012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91569
in ISPRS Journal of photogrammetry and remote sensing > vol 146 (December 2018) . - pp 453 - 464[article]Exemplaires(3)
Code-barres Cote Support Localisation Section Disponibilité 081-2018131 RAB Revue Centre de documentation En réserve L003 Disponible 081-2018133 DEP-EXM Revue LASTIG Dépôt en unité Exclu du prêt 081-2018132 DEP-EAF Revue Nancy Dépôt en unité Exclu du prêt Evaluation of 10-year temporal and spatial variability in structure and growth across contrasting commercial thinning treatments in spruce-fir forests of northern Maine, USA / Christian Kuehne in Annals of Forest Science, vol 75 n° 1 (March 2018)
[article]
Titre : Evaluation of 10-year temporal and spatial variability in structure and growth across contrasting commercial thinning treatments in spruce-fir forests of northern Maine, USA Type de document : Article/Communication Auteurs : Christian Kuehne, Auteur ; Aaron R. Weiskittel, Auteur ; Arne Pommerening, Auteur ; Robert G. Wagner, Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies balsamea
[Termes IGN] arbre aléatoire
[Termes IGN] éclaircie (sylviculture)
[Termes IGN] Maine (Etats-Unis)
[Termes IGN] Picea rubens
[Termes IGN] Pinus strobus
[Termes IGN] station forestière
[Termes IGN] thuja (genre)
[Vedettes matières IGN] SylvicultureRésumé : (Auteur) Key message: Detailed measures of growth pattern and structural heterogeneity applied in this study helped to quantify the immediate effects of various thinning regimes on forest structure and the resulting alterations in tree size as well as observed longer term stand dynamics.
Context: Forest management, stand structure, and tree growth are highly inter-correlated. Prior analyses, however, have resulted in mixed outcomes with limited success in revealing ecological mechanisms.
Aims: The study aimed at evaluating the relationship between forest structure and stand dynamics by applying several sophisticated measures of growth pattern and structural heterogeneity.
Methods : Data from a controlled and fully stem-mapped commercial thinning experiment with seven contrasting treatments including a non-thinned control at six locations across the Acadian Forest of Maine, USA, was used. Stand-level attributes examined included tree size and growth heterogeneity, spatial tree distribution, and growth dominance.
Results: Thinning generally reduced stand structural heterogeneity compared to the non-thinned control. In addition, the spatial arrangement of trees changed from fully random (non-thinned control) to a more clustered (removal of dominant and co-dominant individuals) or regular distribution (removal of intermediate and suppressed individuals). Overall, stand growth exhibited increasing (non-thinned control, removal of intermediate and suppressed individuals) or decreasing growth dominance of large trees (removal of co-dominant competitors). Forwarder trails increased basal area growth of individual trees up to a distance from the trail of approximately 5 m.
Conclusion: Findings of this study validate an earlier insight according to which interactions between management practices, forest structure, and tree growth form a permanent feedback loop.
KeywordsNuméro de notice : A2018-315 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-018-0697-7 Date de publication en ligne : 26/02/2018 En ligne : https://doi.org/10.1007/s13595-018-0697-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90439
in Annals of Forest Science > vol 75 n° 1 (March 2018)[article]Estimation of forest aboveground biomass from HJ1B imagery using a canopy reflectance model and a forest growth model / Xinyun Wang in Geocarto international, vol 33 n° 2 (February 2018)
[article]
Titre : Estimation of forest aboveground biomass from HJ1B imagery using a canopy reflectance model and a forest growth model Type de document : Article/Communication Auteurs : Xinyun Wang, Auteur ; Yige Guo, Auteur ; Jie He, Auteur ; Lingtong Du, Auteur ; Tianhua Hu, Auteur Année de publication : 2018 Article en page(s) : pp 148 - 162 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] biomasse aérienne
[Termes IGN] Chine
[Termes IGN] image HJ-1B
[Termes IGN] juniperus (genre)
[Termes IGN] modèle de croissance végétale
[Termes IGN] Pinophyta
[Termes IGN] Pinus (genre)
[Termes IGN] Populus (genre)
[Termes IGN] réflectance végétale
[Termes IGN] steppe
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] Ulmus (genre)Mots-clés libres : stochastic Gradient boosting Résumé : (Auteur) Accurately estimating the spatial distribution of forest aboveground biomass (AGB) is important because of its carbon budget forms part of the global carbon cycle. This paper presented three methods for obtaining forest AGB based on a forest growth model, a Multiple-Forward-Mode (MFM) method and a stochastic gradient boosting (SGB) model. A Li-Strahler geometric-optical canopy reflectance model (GOMS) with the ZELIG forest growth model was run using HJ1B imagery to derive forest AGB. GOMS-ZELIG simulated data were used to train the SGB model and AGB estimation. The GOMS-ZELIG AGB estimation was evaluated for 24 field-measured data and compared against the GOMS-SGB model and GOMS-MFM biomass predictions from multispectral HJ1B data. The results show that the estimation accuracy of the GOMS-MFM model is slightly higher than that of the GOMS-SGB model. The GOMS-ZELIG and GOMS-MFM models are considerably more accurate at estimating forest AGB in arid and semiarid regions. Numéro de notice : A2018-032 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2016.1232438 En ligne : https://doi.org/10.1080/10106049.2016.1232438 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89205
in Geocarto international > vol 33 n° 2 (February 2018) . - pp 148 - 162[article]Mapping spatial distribution of forest age in China / Yuan Zhang in Earth and space science, vol 4 n° 3 (March 2017)PermalinkDistribution patterns of forest species along an Atlantic-Mediterranean environmental gradient: an approach from forest inventory data / A. Olthoff in Forestry, an international journal of forest research, vol 89 n° 1 (January 2016)PermalinkJuniperus phoenicea growing on cliffs: dendrochronology and wiggle-matching applied to the oldest trees in France / C. Mathaux (2015)PermalinkApproche syntaxonomique et écologique des formations à Genévrier thurifère (Juniperus thurifera L.) dans les Alpes françaises / Luc Garraud in Ecologia mediterranea, vol 40 n° 1 (2014)PermalinkPhytosociological characterization of the Juniperus phoenicea L. subsp. turbinata (Guss.) Nyman formations in the Italo-Tyrrhenian Province (Mediterranean Region) / Lorenzo Gianguzzi in Plant sociology, vol 49 n° 2 (December 2012)PermalinkDocument d’objectifs des sites Natura 2000 N° FR 9301616 « Grand canyon du Verdon et plateau de La palud » - Directive « habitats » et N°FR 9312022 « Verdon » (partie est) - Directive « Oiseaux ». Annexe 1 Données biologiques (document définitif) / Anne Ferment (2010)PermalinkLe Calocèdre : essais de provenances en climat méditerranéen et premiers résultats / Thierry Fauconnier in Forêt méditerranéenne, vol 30 n° 1 (mars 2009)PermalinkProcessing Hyperion and ALI for forest classification / D.G. Goodenough in IEEE Transactions on geoscience and remote sensing, vol 41 n° 6 (June 2003)PermalinkContribution à l'étude des groupements forestiers et pré-forestiers du Maroc oriental / Pierre Quézel in Studia Botanica, vol 10 (1992)PermalinkPiornales, enebrales y pinares oromediterráneos (Pino-Cytision oromediterranei) en el Sistema Central / Salvador Rivas-Martinez in Lazaroa, n° 7 (1985)Permalink