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Wood quality of black spruce and balsam fir trees defoliated by spruce budworm: A case study in the boreal forest of Quebec, Canada / Carlos Paixao in Forest ecology and management, vol 437 (1 April 2019)
[article]
Titre : Wood quality of black spruce and balsam fir trees defoliated by spruce budworm: A case study in the boreal forest of Quebec, Canada Type de document : Article/Communication Auteurs : Carlos Paixao, Auteur ; Cornelia Krause, Auteur ; Hubert Morin, Auteur ; Alexis Achim, Auteur Année de publication : 2019 Article en page(s) : pp 201-210 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies balsamea
[Termes IGN] biomasse forestière
[Termes IGN] bois sur pied
[Termes IGN] croissance des arbres
[Termes IGN] défoliation
[Termes IGN] densité du bois
[Termes IGN] diamètre des arbres
[Termes IGN] données dendrométriques
[Termes IGN] forêt boréale
[Termes IGN] insecte nuisible
[Termes IGN] Picea mariana
[Termes IGN] qualité du bois
[Termes IGN] Québec (Canada)
[Termes IGN] télédétection aérienneRésumé : (auteur) Spruce budworm (SBW – Choristoneura fumiferana Clem.) is one of the most damaging defoliating insects in the coniferous forests of eastern North America. In Canada, the widely distributed balsam fir (Abies balsamea L. (Mill)) and black spruce (Picea mariana B.S.P. (Mill)) are its most important hosts. Defoliation by SBW reduces growth in the host trees and can lead to host mortality. Although SBW impacts on growth are well documented, much less is known about changes in wood properties resulting from defoliation. To address this knowledge gap, we sampled 36 SBW-infested stands located in the boreal forest of Quebec (Canada) to determine whether defoliation modifies the wood quality of affected trees. The selected stands had been subjected to one to four years of SBW defoliation. For both species, we assessed ring growth, wood density, and the anatomical characteristics of stem wood formed during the outbreak years. We determined that rings formed during the SBW outbreak had a significant and progressive loss of biomass production with a longer duration of defoliation. SBW significantly reduced latewood density in the second and third year of defoliation for black spruce and the third and fourth year for balsam fir. Average ring density was reduced only in black spruce and only after four years of defoliation. The observed changes in growth and density were associated with changes in anatomical features. While the cellular characteristics of the earlywood remained fairly constant, significant reductions occurred in latewood cell-wall thickness after three years of defoliation. Our study shows that not only do SBW outbreaks reduce annual radial growth, but the cellular characteristics in latewood cells are also modified momentarily. Thus, SBW outbreaks affect wood density and quality in both black spruce and balsam fir. Numéro de notice : A2019-484 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2019.01.032 Date de publication en ligne : 01/02/2019 En ligne : https://doi.org/10.1016/j.foreco.2019.01.032 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93661
in Forest ecology and management > vol 437 (1 April 2019) . - pp 201-210[article]Forest degradation and biomass loss along the Chocó region of Colombia / Victoria Meyer in Carbon Balance and Management, vol 14 (March 2019)
[article]
Titre : Forest degradation and biomass loss along the Chocó region of Colombia Type de document : Article/Communication Auteurs : Victoria Meyer, Auteur ; Sassan Saatchi, Auteur ; António Ferraz , Auteur ; Liang Xu, Auteur ; Duque Alvaro, Auteur ; Mariano Garcia, Auteur ; Mariano Chave, Auteur Année de publication : 2019 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] apprentissage automatique
[Termes IGN] biomasse aérienne
[Termes IGN] canopée
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] Colombie
[Termes IGN] densité du bois
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] dynamique de la végétation
[Termes IGN] dynamique spatiale
[Termes IGN] forêt tropicale
[Termes IGN] hauteur de la végétation
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] semis de pointsRésumé : (auteur) Background: Wet tropical forests of Chocó, along the Pacific Coast of Colombia, are known for their high plant diversity and endemic species. With increasing pressure of degradation and deforestation, these forests have been prioritized for conservation and carbon offset through Reducing Emissions from Deforestation and forest Degradation (REDD+) mechanisms. We provide the first regional assessment of forest structure and aboveground biomass using measurements from a combination of ground tree inventories and airborne Light Detection and Ranging (Lidar). More than 80,000 ha of lidar samples were collected based on a stratified random sampling to provide a regionally unbiased quantification of forest structure of Chocó across gradients of vegetation structure, disturbance and elevation. We developed a model to convert measurements of vertical structure of forests into aboveground biomass (AGB) for terra firme, wetlands, and mangrove forests. We used the Random Forest machine learning model and a formal uncertainty analysis to map forest height and AGB at 1-ha spatial resolution for the entire pacific coastal region using spaceborne data, extending from the coast to higher elevation of Andean forests.
Results: Upland Chocó forests have a mean canopy height of 21.8 m and AGB of 233.0 Mg/ha, while wetland forests are characterized by a lower height and AGB (13.5 m and 117.5 Mg/a). Mangroves have a lower mean height than upland forests (16.5 m), but have a similar AGB as upland forests (229.9 Mg/ha) due to their high wood density. Within the terra firme forest class, intact forests have the highest AGB (244.3 ± 34.8 Mg/ha) followed by degraded and secondary forests with 212.57 ± 62.40 Mg/ha of biomass. Forest degradation varies in biomass loss from small-scale selective logging and firewood harvesting to large-scale tree removals for gold mining, settlements, and illegal logging. Our findings suggest that the forest degradation has already caused the loss of more than 115 million tons of dry biomass, or 58 million tons of carbon.
Conclusions: Our assessment of carbon stocks and forest degradation can be used as a reference for reporting on the state of the Chocó forests to REDD+ projects and to encourage restoration efforts through conservation and climate mitigation policies.Numéro de notice : A2019-625 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1186/s13021-019-0117-9 Date de publication en ligne : 23/03/2019 En ligne : https://doi.org/10.1186/s13021-019-0117-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95368
in Carbon Balance and Management > vol 14 (March 2019)[article]Estimating net biomass production and loss from repeated measurements of trees in forests and woodlands: Formulae, biases and recommendations / Takashi S. Kohyama in Forest ecology and management, vol 433 (15 February 2019)
[article]
Titre : Estimating net biomass production and loss from repeated measurements of trees in forests and woodlands: Formulae, biases and recommendations Type de document : Article/Communication Auteurs : Takashi S. Kohyama, Auteur ; Tetsuo I. Kohyama, Auteur ; Douglas Sheil, Auteur Année de publication : 2019 Article en page(s) : pp 729 - 740 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] arbre mort
[Termes IGN] biomasse forestière
[Termes IGN] déboisement
[Termes IGN] densité du bois
[Termes IGN] écosystème forestier
[Termes IGN] erreur systématique
[Termes IGN] estimation statistique
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] production primaire brute
[Termes IGN] teneur en carbone
[Vedettes matières IGN] SylvicultureRésumé : (auteur) There is widespread interest in ensuring that assessment and knowledge of changes in forest biomass, and associated carbon gains or losses, are accurate and unbiased. Repeated measurements of individually-marked trees in permanent plots permit the estimation of rates of biomass production by tree growth and recruitment and of loss from mortality. But there are challenges, for example, simple estimates of production rate (i.e., the sum of biomass gain by growth of surviving trees and new recruits divided by census duration) decline as the census interval increases due to unrecorded growth. Even if we allow for these unobserved changes, additional biases may arise due to the non-independence of growth and mortality and to the heterogeneity and compositional changes within the forest. Here we examine these issues and demonstrate how problems can be minimized. We provide and compare alternative approaches to estimate net biomass production and loss from tree growth and mortality. Under the assumption that specific rates of biomass production and loss, i.e., turnover, are constant over time, we derive estimates of absolute biomass turnover rates that are independent of census duration. We show census-interval dependence of simple turnover rates grows with increasing specific turnover rates. While the time-dependent bias in simple estimates has previously been suggested to increase in proportion to the square of production, we show this relationship is approximately linear. Correlations between stem growth and mortality do not influence our estimates. We account for biomass gain by recruited stems without discounting their initial biomass in production estimates. We can reduce additional biases by accounting for differences in turnover among subpopulations (such as species, sites) and changes in their abundances. We provide worked examples from four forests covering a range of conditions (in Indonesia and Japan) and show the effects of accounting for these biases. For example, over five years in an Indonesian rain forest, simple estimates and instantaneous estimates neglecting species heterogeneity underestimated production by 4.9% and 1.6%, respectively when compared to comprehensive (instantaneous species-structured) estimates. Numéro de notice : A2019-010 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2018.11.010 Date de publication en ligne : 08/12/2018 En ligne : https://doi.org/10.1016/j.foreco.2018.11.010 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91604
in Forest ecology and management > vol 433 (15 February 2019) . - pp 729 - 740[article]Analysis and modelling of the wood density variability of the French forest species for the assessment of the forest biomass under climatic change [diaporama] / Jean-Michel Leban (2019)
Titre : Analysis and modelling of the wood density variability of the French forest species for the assessment of the forest biomass under climatic change [diaporama] Type de document : Article/Communication Auteurs : Jean-Michel Leban , Auteur ; Baptiste Kerfriden , Auteur ; Jean-Daniel Bontemps , Auteur Editeur : Paris, Orléans, Nancy, ... [France] : Institut National de la Recherche Agronomique INRA Année de publication : 2019 Projets : XyloDensMap / Leban, Jean-Michel Conférence : IUFRO 2019, 25th World Congress 29/09/2019 05/10/2019 Curitiba Brésil OA abstracts only Importance : 9 p. Langues : Anglais (eng) Descripteur : [Termes IGN] biomasse forestière
[Termes IGN] changement climatique
[Termes IGN] densité du bois
[Termes IGN] forêt tempérée
[Termes IGN] France (administrative)
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) There is an increasing demand on the monitoring of the forest resources, on forests statistics, and on projections of future forest resource availability especially in terms of biomass (Leban & Bontemps, 2016). We developed a new method to enrich the forest information produced by the French National French Inventory by the measurement of the wood density. This technological innovation permits the fast and reliable measurement of the wood density on unprepared increments cores collected in the forests by the NFI staff. The cores are passed through a medical Xray scanner. Since 2015, about thirty thousand cores were sampled each year. At the end of this project, in November 2019 we will have a novel data base with wood density measurements on more than one hundred thousand increment cores. We will present several preliminary results that illustrate the different ways to enrich forest information, e.g. (i) the reassessment of the total standing biomass for the main forest species and (ii) the wood density models that can be used for the simulation of the forest biomass changes at the national level for different climatic hypothesis. We will present and discuss the perspective for the analysis and the sharing of this new data base that combines at the national scale level wood density and the usual forest inventory measurements such as DBH, height, age etc. Such data base pave the avenue for a better understanding of the biomass production along different climatic and trophic gradients. Numéro de notice : C2019-072 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans En ligne : http://docs.gip-ecofor.org/public/B4i-LEBAN-XyloDensMap_project-Analysis_and_mod [...] Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98949 Documents numériques
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Analysis and modelling of the wood density variability ... - diaporamaAdobe Acrobat PDF Biomass ratio varies along soil water availability : An analysis based on wood density data collected by the French NFI / Baptiste Kerfriden (2019)
Titre : Biomass ratio varies along soil water availability : An analysis based on wood density data collected by the French NFI Type de document : Article/Communication Auteurs : Baptiste Kerfriden , Auteur ; Jean-Daniel Bontemps , Auteur ; Jean-Michel Leban , Auteur Editeur : Paris [France] : Institut national de recherche pour l’agriculture, l’alimentation et l’environnement INRAE (2020-) Année de publication : 2019 Conférence : Conference 2019, A century of national forest inventories – informing past, present and future decisions 19/05/2019 21/05/2019 Oslo Norvège programme sans actes Langues : Anglais (eng) Descripteur : [Termes IGN] biomasse forestière
[Termes IGN] changement climatique
[Termes IGN] composition d'un peuplement forestier
[Termes IGN] densité du bois
[Termes IGN] humidité du sol
[Termes IGN] inventaire forestier national (données France)
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Biomass ratio is a state variable allowing the conversion of the forest growing stock into biomass (Kauppi et al., 2006). This variable is most often considered constant per tree species despite the huge range of intraspecific variability of basic density. Indeed, the factors that influence wood density are numerous: tree growth and age, competition (e.g. forest structure), genetics as well as intra and inter annual climatic variations. In light of such diversity, scientific research into forest biomass characteristics is required to better incorporate the heterogeneity of forests in the forest carbon accounting methods (Bowen et al., 2011).
Materials and methods: In 2016 and 2017 over fifty five thousands increment cores were collected in the field by the French NFI. Wood density measurements were performed at INRA (Leban et al., 2019, this conference) and combined with the French NFI calculation system, biomass ratio can now be computed as a standard. This quantity can now be depicted over stratification variables such as soil water availability. An exploratory and ANOVA-assisted analysis of this gradient was performed.
Results: Biomass ratio was found strongly related to soil water availability, with a decrease of biomass ratio at the hardwood and softwood scale, but no correlation were found at the specie level. Explanations come from the species repartition along the gradients from high wood density to low density driven by soil water availability.
Conclusion: Wood density data acquired on the French NFI allow major steps forward toward the proper estimate of forest biomass resources and of carbon sequestration. Biomass ratio was found correlated with climatic contexts, suggesting that biomass sequestration at constant volume may increase in a warmer climate. But this change will be made through change of composition of the forest rather than an adaptation of the species.Numéro de notice : C2019-049 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Poster nature-HAL : Poster-avec-CL DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95768 CarDen: A software for fast measurement of wood density on increment cores by CT scanning / Philippe Jacquin in Computers and Electronics in Agriculture, vol 156 (January 2019)PermalinkWood density reduced while wood volume growth accelerated in Central European forests since 1870 / Hans Pretzsch in Forest ecology and management, vol 429 (1 December 2018)PermalinkWithin- and between-tree variation of wood density components in Pinus nigra at six sites in Portugal / Alexandra Dias in Annals of Forest Science, vol 75 n° 2 (June 2018)PermalinkMapping forest characteristics at fine resolution across large landscapes of the southeastern united states using NAIP imagery and FIA field plot data / John Hogland in ISPRS International journal of geo-information, vol 7 n° 4 (April 2018)PermalinkA critical analysis of methods for rapid and nondestructive determination of wood density in standing trees / Shan Gao in Annals of Forest Science, vol 74 n° 2 (June 2017)PermalinkX-ray microdensitometry of wood: A review of existing principles and devices / Philippe Jacquin in Dendrochronologia, vol 42 (March 2017)PermalinkWithin-stem maps of wood density and water content for characterization of species: a case study on three hardwood and two softwood species / Fleur Longuetaud in Annals of Forest Science, vol 73 n° 3 (September 2016)PermalinkAllometric models for estimating tree volume and aboveground biomass in lowland forests of Tanzania / Wilson Ancelm Mugasha in International journal of forestry research, vol 2016 ([01/08/2016])PermalinkVariations in the natural density of European oak wood affect thermal degradation during thermal modification / Joël Hamada in Annals of Forest Science, vol 73 n° 2 (June 2016)PermalinkInvestigating the possible impact of atmospheric CO2 increase on Araucaria araucana wood density / Paulina E. Pinto in European Journal of Forest Research, vol 135 n° 2 (April 2016)Permalink