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Investigating 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)
[article]
Titre : Investigating the possible impact of atmospheric CO2 increase on Araucaria araucana wood density Type de document : Article/Communication Auteurs : Paulina E. Pinto, Auteur ; Jean-Daniel Bontemps , Auteur ; Jean-Claude Pierrat, Auteur ; Tony Franceschini, Auteur ; Pierre Gelhaye, Auteur ; Jean-Claude Gégout, Auteur ; Jean-Michel Leban , Auteur Année de publication : 2016 Article en page(s) : pp 389 - 401 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Environnement
[Termes IGN] Araucaria araucana
[Termes IGN] Chili
[Termes IGN] Cordillère des Andes
[Termes IGN] dendrométrie
[Termes IGN] densité du bois
[Termes IGN] forêt tempérée
[Termes IGN] puits de carboneRésumé : (auteur) Our aim was to investigate the possible enhancing role of long-term atmospheric CO2 increase on wood density as an essential component of biomass sequestration. We therefore assessed the long-term evolution of wood density over pre-industrial and contemporary periods, in a regional context free of management practices, atmospheric deposition and with restricted climatic change. Dominant trees of Araucaria araucana were sampled in 37 stands distributed throughout its natural distribution over temperate forests of the Chilean Andes Cordillera. Mean ring density (MRD) at 1.30 m was measured by X-ray micro-densitometry. A third-century MRD chronology was built after MRD standardisation by the effects of cambial age and radial growth, simultaneously estimated from a statistical model from rings of the pre-industrial period (1700–1850) to avoid any temporal bias. The age-alone standardised MRD chronology showed restricted fluctuations ranging between 2.0 and 3.2 % over the last three centuries. Multi-decennial fluctuations between ring width and MRD were found qualitatively synchronous and opposed. Accordingly, MRD fluctuations were removed with the age and growth standardisation, highlighting the absence of a historical wood density trend at constant ring size over the whole period. Over the most recent decades however, a slight increase in density was identified, with loss of synchronisation to radial growth. The absence of a long-term signal in wood density of A. araucana, in a context of restricted anthropogenic influence, differs markedly from reports of significant decreases in the Northern Hemisphere. We conclude as part of the analysis done that until now, increasing atmospheric CO2 unlikely would have an impact in wood density. Numéro de notice : A2016--085 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10342-016-0942-2 Date de publication en ligne : 03/03/2016 En ligne : http://doi.org/10.1007/s10342-016-0942-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84570
in European Journal of Forest Research > vol 135 n° 2 (April 2016) . - pp 389 - 401[article]When tree rings behave like foam : moderate historical decrease in the mean ring density of common beech paralleling a strong historical growth increase / Jean-Daniel Bontemps in Annals of Forest Science, Vol 70 n° 4 (June 2013)
[article]
Titre : When tree rings behave like foam : moderate historical decrease in the mean ring density of common beech paralleling a strong historical growth increase Type de document : Article/Communication Auteurs : Jean-Daniel Bontemps , Auteur ; Pierre Gelhaye, Auteur ; Gérard Nepveu, Auteur ; Jean-Christophe Hervé (1961-2017) , Auteur Année de publication : 2013 Article en page(s) : pp 329 - 343 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse diachronique
[Termes IGN] croissance des arbres
[Termes IGN] dendrologie
[Termes IGN] dendrométrie
[Termes IGN] densité du bois
[Termes IGN] estimation statistique
[Termes IGN] Fagus sylvatica
[Termes IGN] puits de carbone
[Vedettes matières IGN] BotaniqueRésumé : (auteur) Context : While historical increases in forest growth have been largely documented, investigations on historical wood density changes remain anecdotic. They suggest possible density decreases in softwoods and ring-porous hardwoods, but are lacking for diffuse-porous hardwoods.
Aims : To evaluate the historical change in mean ring density of common beech, in a regional context where a ring-porous hardwood and a softwood have been studied, and assess the additional effect of past historical increases in radial growth (+50 % over 100 years), resulting from the existence of a positive ring size–density relationship in broadleaved species.
Methods : Seventy-four trees in 28 stands were sampled in Northeastern France to accurately separate developmental stage and historical signals in ring attributes. First, the historical change in mean ring density at 1.30 m (X-ray microdensitometry) was estimated statistically, at constant developmental stage and ring width. The effect of past growth increases was then added to assess the net historical change in wood density.
Results : A progressive centennial decrease in mean ring density of −55 kg m−3 (−7.5 %) was identified (−10 % following the most recent decline). The centennial growth increase induced a maximum +25 kg m−3 increase in mean ring density, whose net variation thus remained negative (−30 kg m−3).
Conclusions : This finding of a moderate but significant decrease in wood density that exceeds the effect of the positive growth change extends earlier reports obtained on other wood patterns in a same regional context and elsewhere. Despite their origin not being understood, such decreases hence form an issue for forest carbon accounting.Numéro de notice : A2013-828 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Article DOI : 10.1007/s13595-013-0263-2 Date de publication en ligne : 21/02/2013 En ligne : https://doi.org/10.1007/s13595-013-0263-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83727
in Annals of Forest Science > Vol 70 n° 4 (June 2013) . - pp 329 - 343[article]