Centre dedocumentation
scientifique

Problems with models assessing influences of tree size and inter-tree competitive processes on individual tree growth: a cautionary tale / P.W. West in Journal of Forestry Research, vol 33 n° 2 (April 2022)  

Public [article]  inJournal of Forestry Research > vol 33 n° 2 (April 2022) . - pp 565 - 577 Titre : Problems with models assessing influences of tree size and inter-tree competitive processes on individual tree growth: a cautionary tale Type de document : Article/Communication Auteurs : P.W. West, Auteur ; D.A. Ratkowsky, Auteur Année de publication : 2022 Article en page(s) : pp 565 - 577 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] arbre (flore) [Termes IGN] Australie [Termes IGN] croissance végétale [Termes IGN] Eucalyptus pilularis [Termes IGN] forêt équienne [Termes IGN] hauteur des arbres [Termes IGN] modèle de croissance végétale [Termes IGN] régression non linéaire [Termes IGN] surface terrière [Vedettes matières IGN] Foresterie Résumé : (auteur) In forest growing at any one site, the growth rate of an individual tree is determined principally by its size, which reflects its metabolic capacity, and by competition from neighboring trees. Competitive effects of a tree may be proportional to its size; such competition is termed ‘symmetric’ and generally involves competition below ground for nutrients and water from the soil. Competition may also be ‘asymmetric’, where its effects are disproportionate to the size of the tree; this generally involves competition above ground for sunlight, when larger trees shade smaller, but the reverse cannot occur. This work examines three model systems often seen as exemplars relating individual tree growth rates to tree size and both competitive processes. Data of tree stem basal area growth rates in plots of even-aged, monoculture forest of blackbutt (Eucalyptus pilularis Smith) growing in sub-tropical eastern Australia were used to test these systems. It was found that none could distinguish between size and competitive effects at any time in any one stand and, thus, allow quantification of the contribution of each to explaining tree growth rates. They were prevented from doing so both by collinearity between the terms used to describe each of the effects and technical problems involved in the use of nonlinear least-squares regression to fit the models to any one data set. It is concluded that quite new approaches need to be devised if the effects on tree growth of tree size and competitive processes are to be quantified and modelled successfully. Numéro de notice : A2022-335 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article Date de publication en ligne : 04/10/2021 En ligne : https://doi.org/10.1007/s11676-021-01395-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100673 [article]

Assessing the dependencies of scots pine (Pinus sylvestris L.) structural characteristics and internal wood property variation / Ville Kankare in Forests, vol 13 n° 3 (March 2022)  

Public [article]  inForests > vol 13 n° 3 (March 2022) . - n° 397 Titre : Assessing the dependencies of scots pine (Pinus sylvestris L.) structural characteristics and internal wood property variation Type de document : Article/Communication Auteurs : Ville Kankare, Auteur ; Ninni Saarinen, Auteur ; Jiri Pyorala, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 397 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie [Termes IGN] biomasse forestière [Termes IGN] croissance des arbres [Termes IGN] dendrochronologie [Termes IGN] densité du bois [Termes IGN] diamètre à hauteur de poitrine [Termes IGN] données lidar [Termes IGN] éclaircie (sylviculture) [Termes IGN] Finlande [Termes IGN] forêt équienne [Termes IGN] modèle linéaire [Termes IGN] Pinus sylvestris [Termes IGN] puits de carbone [Termes IGN] semis de points [Termes IGN] structure d'un peuplement forestier [Termes IGN] variation de densité Résumé : (auteur) Wood density is well known to vary between tree species as well as within and between trees of a certain species depending on the growing environment causing uncertainties in forest biomass and carbon storage estimation. This has created a need to develop novel methodologies to obtain wood density information over multiple tree communities, landscapes, and ecoregions. Therefore, the aim of this study was to evaluate the dependencies between structural characteristics of Scots pine (Pinus sylvestris L.) tree communities and internal wood property (i.e., mean wood density and ring width) variations at breast height. Terrestrial laser scanning was used to derive the structural characteristics of even-aged Scots pine dominated forests with varying silvicultural treatments. Pearson’s correlations and linear mixed effect models were used to evaluate the interactions. The results show that varying silvicultural treatments did not have a statistically significant effect on the mean wood density. A notably stronger effect was observed between the structural characteristics and the mean ring width within varying treatments. It can be concluded that single time terrestrial laser scanning is capable of capturing the variability of structural characteristics and their interactions with mean ring width within different silvicultural treatments but not the variation of mean wood density. Numéro de notice : A2027-208 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.3390/f13030397 Date de publication en ligne : 28/02/2022 En ligne : https://doi.org/10.3390/f13030397 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100025 [article]

A stand-level growth and yield model for thinned and unthinned even-aged Scots pine forests in Norway / Christian Kuehne in Silva fennica, vol 56 n° 1 (January 2022)  

Public [article]  inSilva fennica > vol 56 n° 1 (January 2022) . - n° 1 Titre : A stand-level growth and yield model for thinned and unthinned even-aged Scots pine forests in Norway Type de document : Article/Communication Auteurs : Christian Kuehne, Auteur ; J. Paul McLean, Auteur ; Kobra Maleki, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 1 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] branche (arbre) [Termes IGN] éclaircie (sylviculture) [Termes IGN] forêt équienne [Termes IGN] gestion forestière [Termes IGN] hauteur des arbres [Termes IGN] modèle de croissance végétale [Termes IGN] Norvège [Termes IGN] Pinus sylvestris [Termes IGN] rendement [Termes IGN] surface terrière [Termes IGN] volume en bois [Vedettes matières IGN] Sylviculture Résumé : (auteur) Management of Scots pine (Pinus sylvestris L.) in Norway requires a forest growth and yield model suitable for describing stand dynamics of even-aged forests under contemporary climatic conditions with and without the effects of silvicultural thinning. A system of equations forming such a stand-level growth and yield model fitted to long-term experimental data is presented here. The growth and yield model consists of component equations for (i) dominant height, (ii) stem density (number of stems per hectare), (iii) total basal area, (iv) and total stem volume fitted simultaneously using seemingly unrelated regression. The component equations for stem density, basal area, and volume include a thinning modifier to forecast stand dynamics in thinned stands. It was shown that thinning significantly increased basal area and volume growth while reducing competition related mortality. No significant effect of thinning was found on dominant height. Model examination by means of various fit statistics indicated no obvious bias and improvement in prediction accuracy in comparison to existing models in general. An application of the developed stand-level model comparing different management scenarios exhibited plausible long-term behavior and we propose this is therefore suitable for national deployment. Numéro de notice : A2022-171 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.14214/sf.10627 Date de publication en ligne : 26/01/2022 En ligne : https://doi.org/10.14214/sf.10627 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99806 [article]

Improving the Fagacées growth model with an expanded common beech (Fagus sylvatica L.) data series from France and Germany / Gilles Le Moguédec in Annals of Forest Science [en ligne], vol 78 n° 4 (December 2021)  

Public [article]  inAnnals of Forest Science [en ligne] > vol 78 n° 4 (December 2021) . - n° 84 Titre : Improving the Fagacées growth model with an expanded common beech (Fagus sylvatica L.) data series from France and Germany Type de document : Article/Communication Auteurs : Gilles Le Moguédec, Auteur ; Sidonie Artru, Auteur ; Axel Albrecht, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 84 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] allométrie [Termes IGN] Fagus sylvatica [Termes IGN] forêt équienne [Termes IGN] France (administrative) [Termes IGN] hauteur des arbres [Termes IGN] jeu de données [Termes IGN] modèle de croissance végétale [Termes IGN] modélisation de la forêt [Termes IGN] Quercus (genre) [Termes IGN] République fédérale d'Allemagne [Vedettes matières IGN] Inventaire forestier Résumé : (auteur) Key message: The Fagacées growth model was originally designed for application in the Northern half of France. It is a robust model with potential applicability to a larger area, though this potential has not yet been verified. We added new data to the original parameterization data set and our results show that the Fagacées formalism can be generalized. Context: The Fagacées growth and yield model was designed for the management of pure even-aged stands of European beech and served as a prototype to build models for other tree species. Aims: The objective of this study was to improve the growth components of the Fagacées model with additional data from North-Western France to South-Western Germany. Material and methods: Our model was calibrated on several forest inventory data sets. The first one (F) is the original data set that was used to elaborate the equations in the Fagacées model. The second one (F+) is the original data set extended with additional measurements on the same sites and on new sites in Northern France. The third (G) adds complementary data from a forest network in Southwestern Germany. The last one (A) is the aggregate of all these data sets. Results: Fitting the original model equations on the extended F+ dataset led us to modify the equation for stand basal area increment. This new equation also fit the German dataset well. The other equations could be applied to all datasets, some with the same parameter values and some after recalibrating according to the dataset. Conclusion: We conclude that the general form of the model’s equations is appropriate for application to other regions, but that a recalibration of the equations is preferable in order to reflect local conditions. The advantage of our approach is that fewer data are required to recalibrate an existing equation than to establish an entirely new one. Numéro de notice : A2021-695 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-021-01086-9 Date de publication en ligne : 20/09/2021 En ligne : https://doi.org/10.1007/s13595-021-01086-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98525 [article]

Effects of thinning practice, high pruning and slash management on crop tree and stand growth in young even-aged stands of planted silver birch (Betula pendula Roth) / Jens Peter Skovsgaard in Forests, vol 12 n° 2 (February 2021)  

Public [article]  inForests > vol 12 n° 2 (February 2021) . - n° 225 Titre : Effects of thinning practice, high pruning and slash management on crop tree and stand growth in young even-aged stands of planted silver birch (Betula pendula Roth) Type de document : Article/Communication Auteurs : Jens Peter Skovsgaard, Auteur ; Ulf Johansson, Auteur ; Emma Hölmstrom, Auteur ; Rebecka McCarthy Tune, Auteur ; Clémentine Ols , Auteur ; Giulia Attocchi, Auteur Année de publication : 2021 Projets : ARBRE / AgroParisTech, LUE / Université de Lorraine Article en page(s) : n° 225 Note générale : bibliographie This work was supported by the Swedish forest-owner association Södra and the Swedish national research program Future Forests. C. Ols was funded by the French National Research Agency (ANR-11-LABX-0002-01 and ANR-15-IDEX-04-LUE) during her review and editing of the paper. Langues : Anglais (eng) Descripteur : [Termes IGN] Betula pendula [Termes IGN] Canada [Termes IGN] croissance des arbres [Termes IGN] éclaircie (sylviculture) [Termes IGN] élagage (sylviculture) [Termes IGN] étude d'impact [Termes IGN] forêt équienne [Termes IGN] Suède [Termes IGN] volume en bois [Vedettes matières IGN] Sylviculture Résumé : (auteur) The objective was to quantify the influence of thinning, high pruning and slash management on crop tree and stand growth in young even-aged stands of planted silver birch (Betula pendula Roth). This study was based on two field experiments, aged six and eleven years at initiation and re-measured after six and eight years, respectively. Treatments included the unthinned control, moderate thinning mainly from below (removing 28–33% of standing volume), point thinning to favor 300 trees per ha and with no thinning elsewhere in the plot (removing 16–25%), and heavy thinning leaving 600 evenly distributed potential future crop trees per ha (removing 64–75%). Slash management (extraction or retention) was applied to heavily thinned plots. High pruning removing 30–70% of the green crown was carried out in some plots with point or heavy thinning on 300 or 600 trees per ha, respectively. Stand volume growth increased with increasing pre-treatment mean annual volume increment and decreased with increasing thinning intensity as compared to the unthinned control. LS-means estimates indicated a reduction for moderate thinning by 14%, for point thinning by 12% and for heavy thinning (combined with pruning) by 62%. However, in the youngest experiment, heavy thinning (without pruning) reduced growth by 54%. Combining these results with results from a similar experiment in Canada, the reduction in stand volume growth (RedIv%) depending on thinning removal (RemV%), both expressed as a percentage of the unthinned control, was quantified as RedIv% = −23.67 + 1.16·RemV% (calibration range: 30–83%). For heavy thinning (large quantities of slash), slash extraction resulted in no reduction in stand volume growth as compared to slash retention. The instantaneous numeric reduction in the average stem diameter of the 300 thickest trees per ha (D300) due to thinning was 3.5, 15–21% and 955–11% with moderate, point and heavy thinning, respectively. The subsequent average annual increase in D300 during the observation period was 8.5%, 25 and 18%, respectively. In the youngest experiment, pruning in unthinned plots led to a reduction in the annual increase of D300 by 14%, and heavy thinning in unpruned plots led to an increase by 30%. The growth of pre-selected potential future crop trees increased with increasing thinning intensity. In heavily thinned plots, pruning reduced growth increasingly with increasing pruning severity; LS-means estimates indicated 21% larger growth on stem diameter for unpruned trees and 3% for pruned trees. As an adverse side effect, heavily thinned plots with only 600 trees per ha were at increased risk of windthrow for some years after the thinning intervention. In the oldest experiment, 95–21% of the trees in these plots were damaged by wind. Numéro de notice : A2021-171 Affiliation des auteurs : LIF+Ext (2020- ) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/f12020225 Date de publication en ligne : 16/02/2021 En ligne : https://doi.org/10.3390/f12020225 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97132 [article]

Boreal peatland forests: ditch network maintenance effort and water protection in a forest rotation framework / Jenny Miettinen in Canadian Journal of Forest Research, vol 50 n° 10 (October 2020)  

Permalink

FORESTIMATOR : 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)  

Permalink

Significant differences and curvilinearity in the self-thinning relationships of 11 temperate tree species assessed from forest inventory data / Marie Charru in Annals of Forest Science, Vol 69 n° 2 (March 2012)  

Permalink

Tree diameter, height and stocking in even-aged forests / Jerome K. Vanclay in Annals of Forest Science, Vol 66 n° 7 (October - November 2009)  

Permalink

Les sols du massif forestier des Landes de Gascogne : formation, histoire, propriétés et variabilité spatiale / Claudy Jolivet in Revue forestière française, vol 59 n° 1 (janvier - février 2007)  

Permalink