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A tree-based approach to estimate wood volume from lidar data: a case study in a pine plantation / Ahmed Hamrouni in Revue Française de Photogrammétrie et de Télédétection, n° 211 - 212 (juillet - décembre 2015)
[article]
Titre : A tree-based approach to estimate wood volume from lidar data: a case study in a pine plantation Type de document : Article/Communication Auteurs : Ahmed Hamrouni, Auteur ; Cédric Vega , Auteur ; Jean-Pierre Renaud , Auteur ; Sylvie Durrieu, Auteur ; Marine Bouvier, Auteur Année de publication : 2015 Article en page(s) : pp 63 - 70 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] cubage de peuplement
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] houppier
[Termes IGN] lasergrammétrie
[Termes IGN] Pinus (genre)
[Termes IGN] Pinus pinaster
[Termes IGN] placette d'échantillonnage
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Nous proposons une méthode pour estimer le volume d'arbres individuels d'une zone dominée par des pins maritimes, à partir de données LiDAR aéroporté. Le nuage de points a été segmenté à partir de l'algorithme PTrees. Pour chaque arbre segmenté, la hauteur du plus haut point, le volume de l'enveloppe du nuage et de l'enveloppe de la couronne ont été utilisés dans des modèles non linéaires pour prédire le volume total d'arbres mesurés sur le terrain. A l'arbre, les modèles testés permettent d'estimer le volume avec une erreur quadratique moyenne (RMSE) de l'ordre de 35%. Ce niveau d'erreur a plusieurs origines. Tout d'abord les volumes terrain ont été estimés à partir de tarifs de cubage qui décrivent un arbre moyen. Ainsi une variabilité autour de cet arbre moyen peut être induite par des variations de fertilité ou de sylviculture qui agissent localement sur la croissance des arbres. Le passage à la placette permet de diminuer la RMSE d'un facteur 2, autour de 15%. Ce changement d'échelle permet en effet de compenser les erreurs liées à la segmentation et qui se traduisent par des fausses détections d'arbres soit omissions qui génèrent des fusions de couronnes. Par ailleurs, nos résultats suggèrent que des paramètres de hauts niveaux, tel que la hauteur de la base du houppier, ou le volume de la couronne peuvent introduire du bruit dans les modèles. Nous recommandons donc de sélectionner les variables LiDAR afin de limiter la propagation d'erreur, tout en ajoutant des variables permettant de décrire l'environnement de l'arbre afin de mieux prendre en compte ses conditions de croissance. Numéro de notice : A2015-905 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueNat DOI : 10.52638/rfpt.2015.555 En ligne : https://doi.org/10.52638/rfpt.2015.555 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79562
in Revue Française de Photogrammétrie et de Télédétection > n° 211 - 212 (juillet - décembre 2015) . - pp 63 - 70[article]Comparing individual-tree approaches for predicting height growth of underplanted seedlings / John M. Lhotka in Annals of Forest Science, vol 72 n° 4 (June 2015)
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Titre : Comparing individual-tree approaches for predicting height growth of underplanted seedlings Type de document : Article/Communication Auteurs : John M. Lhotka, Auteur ; Edward F. Loewenstein, Auteur Année de publication : 2015 Article en page(s) : pp 469 - 477 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] canopée
[Termes IGN] Géorgie (Etats-Unis)
[Termes IGN] hauteur des arbres
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] Liriodendron tulipifera
[Termes IGN] modèle de croissance végétale
[Termes IGN] plantation forestière
[Termes IGN] Quercus nigra
[Termes IGN] sous-bois
[Termes IGN] sylvicultureRésumé : (auteur) Key message : Individual-tree seeding height growth models developed using tree inventory data were comparable to those requiring the unique observation of point-based canopy structure data at each seedling.
Context : Quantitative approaches describing the relationship between canopy structure and seedling growth can inform silvicultural decision making regarding the development of tree reproduction beneath a dominant forest canopy.
Aims : Individual-tree seedling growth models with canopy structure predictors derived from tree inventory data have not been well-explored. This study compared a model framework fit using point-based measures of canopy structure observed at the seedling level to one fit using area-wide canopy structure variables derived from standard inventory plot data.
Methods : Species-specific models predicting 5-year height growth were fit for cherrybark oak (Quercus pagoda Raf.), water oak (Quercus nigra L.), and yellow-poplar (Liriodendron tulipifera L.) underplanted within a canopy structure gradient created by silvicultural manipulation of a closed-canopy forest in Georgia, USA.
Results : Though the species varied in shade tolerance and growth rates, the general relationship between the predictor variables and height growth was similar among species and model type. Models highlight the importance of including predictor variables that describe seedling size along with openness and vertical structure of the forest canopy.
Conclusion : While the two model frameworks had comparable fit statistics, the one with predictors derived from tree inventory data may have enhanced utility as it can be directly integrated into existing individual-tree forest growth simulators.Numéro de notice : A2015-424 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s13595-014-0453-6 Date de publication en ligne : 16/01/2015 En ligne : https://doi.org/10.1007/s13595-014-0453-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77014
in Annals of Forest Science > vol 72 n° 4 (June 2015) . - pp 469 - 477[article]Stand volume models based on stable metrics as from multiple ALS acquisitions in Eucalyptus plantations / Eric Bastos Görgens in Annals of Forest Science, vol 72 n° 4 (June 2015)
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Titre : Stand volume models based on stable metrics as from multiple ALS acquisitions in Eucalyptus plantations Type de document : Article/Communication Auteurs : Eric Bastos Görgens, Auteur ; Petteri Packalen, Auteur ; André Gracioso Peres da Silva, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 489 - 498 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] cubage de peuplement
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] données multisources
[Termes IGN] Eucalyptus (genre)
[Termes IGN] semis de points
[Termes IGN] spatial metricsRésumé : (auteur) Key message : The selection of stable metrics can generate reliable models between different data sets. The height metrics provide the greatest stability, specifically the higher percentiles and the mode. Height metrics transfer more predictive power than density metrics.
Context : In forestry, there is an increasing development of aerial laser scanning (ALS). The flight missions that permit to record ALS point clouds are not yet standardized. Therefore, there is a need to identify the metrics that permit to infer robust forest stand estimates from the different point cloud acquisitions.
Aims : The aim of this study is to identify stable metrics derived from different ALS data sets to be used as independent variable in stand volume models.
Methods : Three different ALS data sets were taken from the same Eucalyptus plantation on the same day, each differing from the others in terms of flight altitude, laser power, and pulse frequency rate. Two sets of best predictive models were obtained for each data set based on two approaches: a basic approach using noncollinear metrics and an exhaustive search, and a second approach that added a pairwise Kolmogorov-Smirnov test to select stable metrics.
Results : Height metrics proved more stable, especially higher percentiles (>50 %) and the mode. Models developed with stable metrics had similar performance compared to the basic approach.
Conclusion : Percentiles higher than 50 % and the mode proved stable for that 6-year-old Eucalyptus plantation with a very homogeneous vertical structure. Further research widening the scope in terms of age and heterogeneity of vertical profiles is needed.Numéro de notice : A2015-426 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1007/s13595-015-0457-x Date de publication en ligne : 28/01/2015 En ligne : https://doi.org/10.1007/s13595-015-0457-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77015
in Annals of Forest Science > vol 72 n° 4 (June 2015) . - pp 489 - 498[article]Validation of canopy height profile methodology for small-footprint full-waveform airborne LiDAR data in a discontinuous canopy environment / Karolina D. Fieber in ISPRS Journal of photogrammetry and remote sensing, vol 104 (June 2015)
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Titre : Validation of canopy height profile methodology for small-footprint full-waveform airborne LiDAR data in a discontinuous canopy environment Type de document : Article/Communication Auteurs : Karolina D. Fieber, Auteur ; Ian J. Davenport, Auteur ; Mihai A. Tanase, Auteur ; James M. Ferryman, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 144 - 157 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] Australie
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] forme d'onde pleine
[Termes IGN] hauteur des arbres
[Termes IGN] Leaf Area Index
[Termes IGN] modèle numérique de surface de la canopéeRésumé : (auteur) A Canopy Height Profile (CHP) procedure presented in Harding et al. (2001) for large footprint LiDAR data was tested in a closed canopy environment as a way of extracting vertical foliage profiles from LiDAR raw-waveform. In this study, an adaptation of this method to small-footprint data has been shown, tested and validated in an Australian sparse canopy forest at plot- and site-level. Further, the methodology itself has been enhanced by implementing a dataset-adjusted reflectance ratio calculation according to Armston et al. (2013) in the processing chain, and tested against a fixed ratio of 0.5 estimated for the laser wavelength of 1550 nm. As a by-product of the methodology, effective leaf area index (LAIe) estimates were derived and compared to hemispherical photography values. To assess the influence of LiDAR aggregation area size on the estimates in a sparse canopy environment, LiDAR CHPs and LAIes were generated by aggregating waveforms to plot- and site-level footprints (plot/site-aggregated) as well as in 5 m grids (grid-processed). LiDAR profiles were then compared to field biomass profiles generated based on field tree measurements. The correlation between field and LiDAR profiles was very high, with a mean R2 of 0.75 at plot-level and 0.86 at site-level for 55 plots and the corresponding 11 sites. Gridding had almost no impact on the correlation between LiDAR and field profiles (only marginally improvement), nor did the dataset-adjusted reflectance ratio. However, gridding and the dataset-adjusted reflectance ratio were found to improve the correlation between raw-waveform LiDAR and hemispherical photography LAIe estimates, yielding the highest correlations of 0.61 at plot-level and of 0.83 at site-level. This proved the validity of the approach and superiority of dataset-adjusted reflectance ratio of Armston et al. (2013) over a fixed ratio of 0.5 for LAIe estimation, as well as showed the adequacy of small-footprint LiDAR data for LAIe estimation in discontinuous canopy forests. Numéro de notice : A2015-702 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.03.001 En ligne : https://doi.org/10.1016/j.isprsjprs.2015.03.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78338
in ISPRS Journal of photogrammetry and remote sensing > vol 104 (June 2015) . - pp 144 - 157[article]Lidar detection of the ten tallest trees in the Tennessee portion of the Great Smoky Mountains national park / Chris W. Strother in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 5 (May 2015)
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Titre : Lidar detection of the ten tallest trees in the Tennessee portion of the Great Smoky Mountains national park Type de document : Article/Communication Auteurs : Chris W. Strother, Auteur ; Marguerite Madden, Auteur ; Thomas R. Jordan, Auteur ; Andrea Presotto, Auteur Année de publication : 2015 Article en page(s) : pp 407 - 413 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] arbre (flore)
[Termes IGN] arbre remarquable
[Termes IGN] hauteur des arbres
[Termes IGN] lever mobile
[Termes IGN] modèle numérique de surface
[Termes IGN] parc naturel
[Termes IGN] Tennessee (Etats-Unis)Résumé : (auteur) This paper describes a method for predicting the locations and heights of the ten tallest trees in the Tennessee portion of the Great Smoky Mountains National Park. Iterative computation tools were utilized to process the data along with the lidar derived bare earth digital elevation models and digital surface models to create canopy height models for the Tennessee portion of the park. A height threshold of 51.8 meters was chosen as the minimum value for a tree of extraordinary height. Ten potential sites containing tall trees were identified using this methodology, and seven of the top ten ranking trees’ heights were field measured using accepted forestry methodology. The trees detected using these methods are potentially the tallest trees ever measured on the East Coast of the United States. These methods show that unique tall trees can be successfully detected in a large, heterogeneous forest area using lidar data. Numéro de notice : A2015-975 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.81.5.407 En ligne : https://doi.org/10.14358/PERS.81.5.407 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80045
in Photogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 5 (May 2015) . - pp 407 - 413[article]Individual-based approach as a useful tool to disentangle the relative importance of tree age, size and inter-tree competition in dendroclimatic studies / Vicente Rozas in iForest, biogeosciences and forestry, vol 8 n° 2 (April 2015)PermalinkMapping aboveground biomass in northern japanese forests using the ALOS PRISM digital surface model / Takeshi Motohka in IEEE Transactions on geoscience and remote sensing, vol 53 n° 4 (April 2015)PermalinkForest inventory attribute estimation using airborne laser scanning, aerial stereo imagery, radargrammetry and interferometry–Finnish experiences of the 3D techniques / Markus Holopainen in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol II-3 W4 (March 2015)PermalinkCharacterizing stand-level forest canopy cover and height using Landsat time series, samples of airborne LiDAR, and the Random Forest algorithm / Oumer S. Ahmed in ISPRS Journal of photogrammetry and remote sensing, vol 101 (March 2015)PermalinkTree species biomass and carbon stock measurement using ground based-LiDAR / Gurveek Singh Maan in Geocarto international, vol 30 n° 3 - 4 (March - April 2015)PermalinkValidation of terrestrial laser scanning data using conventional forest inventory methods / Taye Mengesha in European Journal of Forest Research, vol 134 n° 2 (March 2015)PermalinkCapabilities of BIOMASS tomography for investigating tropical forests / Ho Tong Minh Dinh in IEEE Transactions on geoscience and remote sensing, vol 53 n° 2 (February 2015)PermalinkEstimation of the mean tree height of forest stands by photogrammetric measurement using digital aerial images of high spatial resolution / Ivan Balenović in Annals of forest research, vol 58 n° 1 (January 2015)PermalinkForest structure indicators based on tree size inequality and their relationships to airborne laser scanning / Rubén Valbuena (2015)PermalinkJuniperus phoenicea growing on cliffs: dendrochronology and wiggle-matching applied to the oldest trees in France / C. Mathaux (2015)Permalink