Descripteur
Termes IGN > sciences naturelles > sciences de la vie > biologie > botanique > dendrologie > dendrométrie > diamètre à hauteur de poitrine
diamètre à hauteur de poitrineVoir aussi |
Documents disponibles dans cette catégorie (92)
Ajouter le résultat dans votre panier Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
Is tree age or tree size reducing height increment in Abies alba Mill. at its southernmost distribution limit? / Pasquale A. Marziliano in Annals of Forest Science, vol 76 n° 1 (March 2019)
[article]
Titre : Is tree age or tree size reducing height increment in Abies alba Mill. at its southernmost distribution limit? Type de document : Article/Communication Auteurs : Pasquale A. Marziliano, Auteur ; Roberto Tognetti, Auteur ; Fabio Lombardi, Auteur Année de publication : 2019 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies alba
[Termes IGN] allométrie
[Termes IGN] Apennins
[Termes IGN] croissance des arbres
[Termes IGN] dendrométrie
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] échantillonnage
[Termes IGN] hauteur des arbres
[Vedettes matières IGN] SylvicultureRésumé : (auteur) Key message : Conventional methods for estimating the current annual increment of stand volume are based on the uncertain assumption that height increment decreases with tree age. Conversely, size, rather than age, should be accounted for the observed senescence-related declines in relative growth rate and, consequently, implemented in silvicultural manuals. Results stem from a study on Abies alba Mill. at its southern limit of distribution.
Context : Many factors limit height increment when age and size increase in large-statured tree species. Height–diameter allometric relationships are commonly used measures of tree growth.
Aims : In this study, we tested if tree age was the main factor affecting the reduction in height increment of silver fir trees (Abies alba Mill.), verifying also whether tree size had a significant role in ecophysiological-biomechanical limitations to tree growth.
Methods : The study was carried out in a silver fir forest located in Southern Italy, at the southernmost distribution limit for this species. Through a stratified random sampling, 100 trees were selected. All the selected trees were then felled and the total tree height, height increments (internode distances), diameter at breast height, and diameter increments (ring widths) were measured.
Results : The analyses of allometric models and scaling coefficients showed that the correlation between tree age and height increment was not always significant.
Conclusion : We may conclude that tree age did not statistically explain the decrease in height increment in older trees. Instead, the increase in tree size and related physiological processes (expressed as product between diameter at breast height and tree height) explained the reduction in height increment in older trees and was the main factor limiting height growth trends in marginal population of silver fir.Numéro de notice : A2019-028 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-019-0803-5 Date de publication en ligne : 13/02/2019 En ligne : https://doi.org/10.1007/s13595-019-0803-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92036
in Annals of Forest Science > vol 76 n° 1 (March 2019)[article]Patterns of tree diameter distributions in managed and unmanaged Abies alba Mill. and Fagus sylvatica L. forest patches / Rafał Podlaski in Forest ecology and management, vol 435 (1 March 2019)
[article]
Titre : Patterns of tree diameter distributions in managed and unmanaged Abies alba Mill. and Fagus sylvatica L. forest patches Type de document : Article/Communication Auteurs : Rafał Podlaski, Auteur ; Tomasz Sobala, Auteur ; Maciej Kocurek, Auteur Année de publication : 2019 Article en page(s) : pp 7 - 105 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] Abies alba
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] diamètre des arbres
[Termes IGN] distribution spatiale
[Termes IGN] Europe centrale
[Termes IGN] Fagus sylvatica
[Termes IGN] forêt tempérée
[Termes IGN] hétérogénéité environnementale
[Termes IGN] phytogéographieRésumé : (Auteur) Temperate forests with shade-tolerant canopy tree species can develop vertical structures of varying complexity. Forests with Abies alba Mill. and Fagus sylvatica L. can be composed of one-, two-, and multi-storied patches and selection patches. A dominant view in forest ecology is that unmanaged forests tend to have greater structural heterogeneity than managed stands. Structural integrity, however, may differ among forest developmental stages. The main objective of this study was to compare the tree diameter complexity in managed and unmanaged patches during the early developmental stage.
Data were collected between 2016 and 2018 in the Świętokrzyskie Mountains in Central Europe. The investigated tree communities were dominated by A. alba and F. sylvatica. Sample plots representing the growing-up developmental stage were randomly selected; of these, 30 plots were in managed stands, and 30 plots were in unmanaged forests. The diameter at breast height (DBH) distribution patterns were determined using hierarchical cluster analysis (HCA), clustering indices, and finite mixture models.
Three main DBH distribution patterns were identified for the managed stands (K-A, K-B, and K-C). These patterns consisted of three or two sub-populations. The patterns represented structurally diversified patches composed of trees of all ages with multi-, three- or two-layered canopies and with intensive natural processes of regeneration. Two main DBH distribution patterns were identified for the unmanaged forests (S-A, and S-B). These patterns consisted of two clearly separated sub-populations. They are typical in patches with two-layered canopies, and the trees from the upper layer had a large share (40–60%). The distinguished DBH distribution patterns indicated there was greater tree size diversity in the managed stands than in the unmanaged forests. When comparing managed versus unmanaged patches, it is important to consider the developmental stage.Numéro de notice : A2019-185 Affiliation des auteurs : non IGN Thématique : FORET/MATHEMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2018.12.046 Date de publication en ligne : 04/01/2019 En ligne : https://doi.org/10.1016/j.foreco.2018.12.046 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92719
in Forest ecology and management > vol 435 (1 March 2019) . - pp 7 - 105[article]Single-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)
[article]
Titre : Single-image photogrammetry for deriving tree architectural traits in mature forest stands: a comparison with terrestrial laser scanning Type de document : Article/Communication Auteurs : Kamil Kędra, Auteur ; Ignacio Barbeito, Auteur ; Mathieu Dassot , Auteur ; Patrick Vallet, Auteur ; Anna Gazda, Auteur Année de publication : 2019 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] allométrie
[Termes IGN] analyse comparative
[Termes IGN] coefficient de corrélation
[Termes IGN] détection d'arbres
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] diamètre des arbres
[Termes IGN] forêt tempérée
[Termes IGN] hauteur des arbres
[Termes IGN] houppier
[Termes IGN] image isolée
[Termes IGN] Orléans, forêt domaniale d' (Loiret)
[Termes IGN] peuplement forestier
[Termes IGN] peuplement mélangé
[Termes IGN] Pinus sylvestris
[Termes IGN] Quercus (genre)
[Termes IGN] télémétrie laser terrestreRésumé : (auteur) Key message : We compared two methods for detailed individual tree measurements: single image photogrammetry (SIP), a simplified, low-cost method, and the state-of-the-art terrestrial laser scanning (TLS). Our results provide evidence that SIP can be successfully applied to obtain accurate tree architectural traits in mature forests.
Context : Tree crown variables are necessary in forest modelling; however, they are time consuming to measure directly, and they are measured in many different ways. We compare two methods to obtain crown variables: laser-based and image-based. TLS is an advanced technology for three-dimensional data acquisition; SIP is a simplified, low-cost method.
Aims : To elucidate differences between the methods, and validate SIP accuracy and usefulness for forest research, we investigated if (1) SIP and TLS measurements are in agreement in terms of the most widely used tree characteristics; (2) differences between the SIP traits and their TLS counterparts are constant throughout tree density and species composition; (3) tree architectural traits obtained with SIP explain differences in laser-based crown projection area (CPA), under different forest densities and stand compositions; and (4) CPA modelled with SIP variables is more accurate than CPA obtained with stem diameter-based allometric models. We also examined the correspondence between local tree densities extracted from images and from field measurements.
Methods : We compared TLS and SIP in a temperate pure sessile oak and mixed with Scots pine stands, in the Orléans Forest, France. Standard major axis regression was used to establish relations between laser-based and image-based tree height and diameter at breast height. Four SIP-derived traits were compared between the levels of stand density and species composition with a t test, in terms of deviations and biases to their TLS counterparts. We created a set of linear and linear mixed models (LMMs) of CPATLS, with SIP variables. Both laser-based and image-based stem diameters were used to estimate CPA with the published allometric equations; the results were then compared with the best predictive LMM, in terms of similarity with CPATLS measurement. Local tree density extracted from images was compared with field measurements in terms of basic statistics and correlation.
Results : Tree height and diameter at breast height were reliably represented by SIP (Pearson correlation coefficients r = 0.92 and 0.97, respectively). SIP measurements were affected by the stand composition factor; tree height attained higher mean absolute deviation (1.09 m) in mixed stands, compared to TLS, than in pure stands (0.66 m); crown width was more negatively biased in mixed stands (− 0.79 m), than in pure stands (− 0.05 m); and diameter at breast height and crown asymmetry were found unaffected. Crown width and mean branch angle were key SIP explanatory variables to predict CPATLS. The model was approximately 2-fold more accurate than the CPA allometric estimations with both laser-based and image-based stem diameters. SIP-derived local tree density was similar to the field-measured density in terms of mean and standard deviation (9.6 (3.5) and 9.4 (3.6) trees per plot, respectively); the correlation between both density measures was significantly positive (r = 0.76).
Conclusion : SIP-derived variables, such as crown width, mean branch angle, branch thickness, and crown asymmetry, were useful to explain tree architectural differences under different densities and stand compositions and may be implemented in many forest research applications. SIP may also provide a coarse measure of local competition, in terms of number of neighbouring trees. Our study provides the first test in mature forest stands, for SIP compared with TLS.Numéro de notice : A2019-044 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-018-0783-x Date de publication en ligne : 07/01/2019 En ligne : https://doi.org/10.1007/s13595-018-0783-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92050
in Annals of Forest Science > vol 76 n° 1 (March 2019)[article]Thinking outside the square: Evidence that plot shape and layout in forest inventories can bias estimates of stand metrics / Thomas S. H. Paul in Methods in ecology and evolution, vol 10 n° 3 (March 2019)
[article]
Titre : Thinking outside the square: Evidence that plot shape and layout in forest inventories can bias estimates of stand metrics Type de document : Article/Communication Auteurs : Thomas S. H. Paul, Auteur ; Mark O. Kimberley, Auteur ; Peter N. Beets, Auteur Année de publication : 2019 Article en page(s) : pp 381 - 388 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] cercle (géométrie)
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] erreur systématique
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] Nouvelle-Zélande
[Termes IGN] placette d'échantillonnage
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Plot‐based data collection is an important component of quantitative ecological research and is widely used. Some of the most extensive plot‐networks can be found in country‐wide forest inventories, which provide critical information about the state of forest ecosystems. While sampling designs for forest inventories have been well studied, plot design and installation has received less attention.
The New Zealand National Forest Inventory of natural forest uses a nested plot design with a 0.126 ha circular plot superimposed concentrically on a 0.04 ha square plot. Stems ≥ 60 cm diameter at breast height (DBH) are measured in the circular plot while stems ≥ 2.5 DBH are measured in the square plot. Stem density of ≥60 cm DBH stems measured in the circular plots were compared with those from square plots.
Stem densities estimated from square plot measurements were 23.7% higher than those estimated from circular plot measurements in the 2002–2007 inventory, and 18.4% higher in the 2009–2014 inventory. The main cause of this discrepancy appears to be due to the placement of plot boundaries during establishment of square plots. This effect may have resulted from a subconscious tendency of field teams to include large trees inside plots when laying out these boundaries. It is concluded that estimates from the circular plots are unlikely to be biased while those from the square plots are positively biased.
This study highlights the critical importance of plot design and plot placement in forest inventories to ensure that estimates of stand attributes are unbiased. Especially on undulating or uneven terrain, methods of determining whether trees are inside or outside plot boundaries of circular plots are likely to be more accurate than those typically used for square or rectangular plots.Numéro de notice : A2019-372 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1111/2041-210X.13113 Date de publication en ligne : 29/10/2018 En ligne : https://doi.org/10.1111/2041-210X.13113 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93409
in Methods in ecology and evolution > vol 10 n° 3 (March 2019) . - pp 381 - 388[article]Predicting tree diameter using allometry described by non-parametric locally-estimated copulas from tree dimensions derived from airborne laser scanning / Qing Xu in Forest ecology and management, vol 434 (28 February 2019)
[article]
Titre : Predicting tree diameter using allometry described by non-parametric locally-estimated copulas from tree dimensions derived from airborne laser scanning Type de document : Article/Communication Auteurs : Qing Xu, Auteur ; Bo Li, Auteur ; Matti Maltamo, Auteur ; Timo Tokola, Auteur ; Zhengyang Hou, Auteur Année de publication : 2019 Article en page(s) : pp 205 - 212 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] allométrie
[Termes IGN] analyse comparative
[Termes IGN] détection d'arbres
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] Finlande
[Termes IGN] hauteur des arbres
[Termes IGN] houppier
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] méthode des moindres carrés
[Termes IGN] télédétection par lidar
[Termes IGN] théorie des probabilitésRésumé : (auteur) Biomass inventories that employ airborne laser scanning (ALS) require models that can predict tree diameter at breast height (DBH) from ALS-derived tree dimensions, as ALS can usually not directly measure DBH due to scanning angle, inadequate point density and canopy obstruction. Although some work has been done in using correlation as a measure of dependence to describe the linear relationship between variable means, none has investigated the copula-based measure of dependence for the prediction of DBH from ALS-derived height and crown diameter. Following the application of a locally-estimated copula method to 79 sample plots in eastern Finland, we compared the performance of the copula method with a baseline local regression (LOESS) model and an ordinary least squares (OLS) model. We found that the copula method outperformed the OLS model by decreasing 30% of the root-mean-squared error (RMSE). The copula method performed slightly better than the LOESS model for the original sample, but the results of the bootstrap samples showed that the variance in RMSE was sixteen times lower in the copula method than the LOESS model, suggesting that the copula had a more consistent and robust model performance across the 10,000 bootstrap samples. Moreover, while the LOESS model only predicts the conditional mean of the response variable, the copula method can also predict median and other quantiles. Numéro de notice : A2019 - 012 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2018.12.020 Date de publication en ligne : 19/12/2018 En ligne : https://doi.org/10.1016/j.foreco.2018.12.020 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91615
in Forest ecology and management > vol 434 (28 February 2019) . - pp 205 - 212[article]A simple approach to forest structure classification using airborne laser scanning that can be adopted across bioregions / Syed Adnan in Forest ecology and management, vol 433 (15 February 2019)PermalinkPermalinkA growth-model-driven technique for tree stem diameter estimation by using airborne LiDAR data / Claudia Paris in IEEE Transactions on geoscience and remote sensing, vol 57 n° 1 (January 2019)PermalinkIs field-measured tree height as reliable as believed – A comparison study of tree height estimates from field measurement, airborne laser scanning and terrestrial laser scanning in a boreal forest / Yunsheng Wang in ISPRS Journal of photogrammetry and remote sensing, vol 147 (January 2019)PermalinkCan forest structural diversity be a response to anthropogenic stress? A case study in old-growth fir Abies alba Mill. stands / Rafał Podlaski in Annals of Forest Science, vol 75 n° 4 (December 2018)PermalinkA comparison of two methods of data collection for modelling productivity of harvesters: manual time study and follow-up study using on-board-computer stem records / Julia Brewer in Annals of forest research, vol 61 n° 1 (January - June 2018)PermalinkAirborne laser scanning for tree diameter distribution modelling: a comparison of different modelling alternatives in a tropical single-species plantation / Matti Maltamo in Forestry, an international journal of forest research, vol 91 n° 1 (January 2018)PermalinkTowards assessment of cork production through National Forest Inventories / Maria Pasalodos-Tato in Forestry, an international journal of forest research, vol 91 n° 1 (January 2018)PermalinkAutomatic mapping of forest stands based on three-dimensional point clouds derived from terrestrial laser-scanning / Tim Ritter in Forests, vol 8 n° 8 (August 2017)PermalinkForest modelling: the gamma shape mixture model and simulation of tree diameter distributions / Rafał Podlaski in Annals of Forest Science, vol 74 n° 2 (June 2017)Permalink