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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)
[article]
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]An improved species distribution model for Scots pine and downy oak under future climate change in the NW Italian Alps / Giorgio Vacchiano in Annals of Forest Science, vol 72 n° 3 (May 2015)
[article]
Titre : An improved species distribution model for Scots pine and downy oak under future climate change in the NW Italian Alps Type de document : Article/Communication Auteurs : Giorgio Vacchiano, Auteur ; Renzo Motta, Auteur Année de publication : 2015 Article en page(s) : pp 321 - 334 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] Aoste (val d')
[Termes IGN] distribution spatiale
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] Pinus sylvestris
[Termes IGN] Quercus pubescens
[Termes IGN] sécheresseRésumé : (auteur) Context : Scots pine is currently declining in most inner alpine sectors of southern Europe. The relative contribution of climate, land use change, and disturbances on the decline is poorly understood. What will be the future distribution of the species? Is vegetation shifting toward oak-dominated forests? What is the role of extreme drought years?
Aims : The aims of the study were to determine drivers of current distribution of Scots pine and downy oak in Aosta valley (SW Alps), to extrapolate species distribution models to year 2080 (Special Report on Emissions Scenarios (SRES) A1B), and to assess the correlation between pine vitality after the extreme droughts of 2003 and 2006, and modeled longterm vegetation changes.
Methods : Ensemble distribution models were created using climate, topography, soil, competition, natural disturbances, and land use. Species presence was derived from a regional forest inventory. Pine response to drought of 2003–2006 was assessed by Normalized Difference Vegetation Index (NDVI) differencing and correlated to modeled cover change between 2080 and present.
Results : Scots pine and downy oak were more likely to occur under higher climatic aridity. Scots pine was also associated to higher wildfire frequency, land use intensity, and lack of competition. In a warming scenario, pine experienced an elevational displacement. This was partially counteracted if no land abandonment was hypothesized. Downy oak cover increased in all scenarios. Short- and long-term drought responses of pine were unrelated.
Conclusion : Warming will induce an upward displacement of pine, but this can be partially mitigated by maintaining a more intense land use. The drought-induced decline in pine vitality after extreme years did not overlap to the modeled species response under climate warming; responses to short-term drought must be more thoroughly understood in order to predict community shifts.Numéro de notice : A2015-454 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s13595-014-0439-4 Date de publication en ligne : 19/12/2014 En ligne : https://doi.org/10.1007/s13595-014-0439-4 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77111
in Annals of Forest Science > vol 72 n° 3 (May 2015) . - pp 321 - 334[article]Augmenter le niveau de production de biomasse des cultures ligneuses dédiées ou semi-dédiées. Principaux enseignements du projet SYLVA BIOM / Jean-Charles Bastien in Revue forestière française, vol 67 n° 3 (mai 2015)
[article]
Titre : Augmenter le niveau de production de biomasse des cultures ligneuses dédiées ou semi-dédiées. Principaux enseignements du projet SYLVA BIOM Type de document : Article/Communication Auteurs : Jean-Charles Bastien, Auteur ; Alain Berthelot, Auteur ; Franck Brignolas, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 249 - 262 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] arbre (flore)
[Termes IGN] biomasse forestière
[Termes IGN] Populus (genre)
[Termes IGN] Salix (genre)
[Termes IGN] sylviculture
[Termes IGN] taillisRésumé : (auteur) Dans le cadre d’un traitement en taillis à courte ou très courte rotation (TCR et TTCR), le projet SYLVABIOM s’est appuyé sur le suivi de la croissance et de l’efficacité avec laquelle les arbres de trois espèces (Peuplier, Robinier et Saule) utilisent l’eau et l’azote dans un réseau de quatre sites ateliers, situés dans des stations contrastées. La pertinence du taux de méthylation de l’ADN en tant que marqueur précoce du niveau de productivité a également été évaluée. Dans le cadre d’un traitement en futaie à courte révolution (FCR), le projet a reposé sur la collecte de données de croissance et de biomasse dans les réseaux expérimentaux, pour construire des tarifs compartimentés (bois de tronc, écorce, branches et feuilles) d’essences forestières à croissance rapide peu ou pas documentées. Des différences significatives ont été mises en évidence, tant en TCR qu’en TTCR, entre les trois espèces, et entre génotypes au sein d’une espèce, pour la production en biomasse, ses déterminants phénologiques, foliaires et architecturaux et l’efficience d’utilisation des ressources. Les relations complexes entre ces caractères sont modulées en fonction des conditions pédoclimatiques et de la densité de plantation. La mesure du taux de méthylation de l’ADN d’apex ou de feuilles pourrait constituer un bon prédicteur du potentiel de croissance chez le Peuplier. Des productions moyennes annuelles de biomasse comprises entre 7 et 13 tonnes de matière sèche par hectare et par an peuvent être espérées autour de 20 ans avec des conifères à croissance rapide cultivés en FCR sur d’autres gammes de stations que les espèces cultivées en TCR ou TTCR. Des gains génétiques très importants sur la production de biomasse sont par ailleurs offerts par sélection de génotypes performants. Numéro de notice : A2015-837 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.4267/2042/58175 En ligne : https://doi.org/10.4267/2042/58175 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79143
in Revue forestière française > vol 67 n° 3 (mai 2015) . - pp 249 - 262[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 133-2015031 SL Revue Centre de documentation Revues en salle Disponible Evaluating leaf chlorophyll content prediction from multispectral remote sensing data within a physically-based modelling framework / H. Croft in ISPRS Journal of photogrammetry and remote sensing, vol 102 (April 2015)
[article]
Titre : Evaluating leaf chlorophyll content prediction from multispectral remote sensing data within a physically-based modelling framework Type de document : Article/Communication Auteurs : H. Croft, Auteur ; Jing M. Chen, Auteur ; Y. Zhang, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 85 - 95 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] Acer saccharum
[Termes IGN] aiguille
[Termes IGN] image Landsat-TM
[Termes IGN] indice de stress
[Termes IGN] Leaf Area Index
[Termes IGN] modèle de transfert radiatif
[Termes IGN] Picea mariana
[Termes IGN] Pinus banksiana
[Termes IGN] Populus tremuloides
[Termes IGN] réflectance végétale
[Termes IGN] surveillance forestière
[Termes IGN] teneur en chlorophylle des feuillesRésumé : (auteur) Accurate modelling of leaf chlorophyll content over a range of spatial and temporal scales is central to monitoring vegetation stress and physiological condition, and vegetation response to different ecological, climatic and anthropogenic drivers. A process-based modelling approach can account for variation in other factors affecting canopy reflectance, providing a more accurate estimate of chlorophyll content across different vegetation species, time-frames, and broader spatial extents. However, physically-based modelling studies usually use hyperspectral data, neglecting a wealth of data from broadband and multispectral sources. In this study, we assessed the potential for using canopy (4-Scale) and leaf radiative transfer (PROSPECT4/5) models to estimate leaf chlorophyll content using canopy Landsat satellite data and simulated Landsat bands from leaf level hyperspectral reflectance data. Over 600 leaf samples were used to test the performance of PROSPECT for different vegetation species, including black spruce (Picea mariana), sugar maple (Acer saccharum), trembling aspen (Populus tremuloides) and jack pine (Pinus banksiana). At the leaf level, hyperspectral and simulated Landsat bands showed very similar results to laboratory measured chlorophyll (R2 = 0.77 and R2 = 0.75, respectively). Comparisons between PROSPECT4 modelled chlorophyll from simulated Landsat and hyperspectral spectra showed a very close correspondence (R2 = 0.97, root mean square error (RMSE) = 3.01 μg/cm2), as did simulated reflectance bands from other broadband and narrowband sensors (MODIS: R2 = 0.99, RMSE = 1.80 μg/cm2; MERIS: R2 = 0.97, RMSE = 2.50 μg/cm2 and SPOT5 HRG: R2 = 0.96, RMSE = 5.38 μg/cm2). Modelled leaf chlorophyll content from Landsat 5 TM canopy reflectance data, acquired from over 40 ground validation sites, demonstrated a strong relationship with measured leaf chlorophyll content (R2 = 0.78, RMSE = 8.73 μg/cm2, p Numéro de notice : A2015-691 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.01.008 En ligne : https://doi.org/10.1016/j.isprsjprs.2015.01.008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78326
in ISPRS Journal of photogrammetry and remote sensing > vol 102 (April 2015) . - pp 85 - 95[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)
[article]
Titre : Individual-based approach as a useful tool to disentangle the relative importance of tree age, size and inter-tree competition in dendroclimatic studies Type de document : Article/Communication Auteurs : Vicente Rozas, Auteur Année de publication : 2015 Article en page(s) : pp 187 - 194 Langues : Anglais (eng) Descripteur : [Termes IGN] changement climatique
[Termes IGN] dendrochronologie
[Termes IGN] feuillu
[Termes IGN] hauteur des arbres
[Termes IGN] Quercus pedunculata
[Termes IGN] stress hydrique
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) In this work, an individual-based approach was used to assess the relative importance of tree age, size, and competition in modulating the individual dendroclimatic response of Quercus robur L. This was performed in a multi-aged forest in northwestern Spain under a wet Atlantic climate. All trees in five replicated forest stands with homogeneous soil conditions were mapped and inter-tree competition was quantified with a distance-dependent competition index. Tree rings of cored trees were crossdated and total age was estimated on individuals where the pith was missed. The climatic response was evaluated by bootstrapped correlations of individual tree-ring chronologies with climatic records. Inter-annual growth variation, i.e., mean sensitivity, was independent of tree age and bole diameter, but modulated by competition. Water excess in previous summer-autumn and spring negatively affected growth, while warmer September conditions favored growth. Individual response to climate was independent of tree age, but related to the joint effect of tree bole diameter and competition. Larger oaks in less competitive environments responded more plastically to climatic stress, while smaller trees under high competition levels were less responsive to climate. Strong inter-tree competition reduced growth plasticity but amplified the vulnerability of smaller oaks to the particularly rainy conditions of the study area. These findings suggest that inter-tree competition is a relevant size-mediated extrinsic factor that can potentially modulate individual radial growth variation and its response to limiting climatic conditions in temperate deciduous forests. This study highlights the value of individual-based approach as a useful tool that informs about the relative contribution of factors modulating the climatic response of tree-ring growth. Numéro de notice : A2015-120 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3832/ifor1249-007 Date de publication en ligne : 21/08/2014 En ligne : https://doi.org/10.3832/ifor1249-007 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75670
in iForest, biogeosciences and forestry > vol 8 n° 2 (April 2015) . - pp 187 - 194[article]Association of tree and plot characteristics with microhabitat formation in European beech and Douglas-fir forests / Susanne Winter in European Journal of Forest Research, vol 134 n° 2 (March 2015)PermalinkBiomass estimation with high resolution satellite images: A case study of Quercus rotundifolia / Adelia M.O. Sousa in ISPRS Journal of photogrammetry and remote sensing, vol 101 (March 2015)PermalinkEvaluating the utility of the medium-spatial resolution Landsat 8 multispectral sensor in quantifying aboveground biomass in uMgeni catchment, South Africa / Timothy Dube in ISPRS Journal of photogrammetry and remote sensing, vol 101 (March 2015)PermalinkSpectroscopic analysis of green, desiccated and dead tamarisk canopies / Ran Meng in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 3 (March 2015)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)PermalinkNon-invasive forest litter characterization using full-wave inversion of microwave radar data / Frédéric André in IEEE Transactions on geoscience and remote sensing, vol 53 n° 2 (February 2015)PermalinkPermalinkMODIS-based vegetation index has sufficient sensitivity to indicate stand-level intra-seasonal climatic stress in oak and beech forests / Tomáš Hlásny in Annals of Forest Science, vol 72 n° 1 (January 2015)PermalinkRetrieving surface variables by integrating ground measurements and earth observation data in forest canopies : a case study in Speuldersbos forest / Kitsiri Weligepolage (2015)PermalinkSatellite data as indicators of tree biomass growth and forest dieback in a Mediterranean holm oak forest / Romà Ogaya in Annals of Forest Science, vol 72 n° 1 (January 2015)Permalink