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Fleur Longuetaud Frédéric Mothe Philippe Santenoise Ndiaye Diop Jana Dlouha Meriem Fournier Christine Deleuze 《Annals of Forest Science》2017,74(3):64
? Key message
Intensive measurements of basic specific gravity and relative water content of lumens show that within-stem variations strongly depend on species and cannot be summarised through the typical patterns reported in the literature; breast height measurements are not always representative of the whole stem.? Context
Knowledge of the distribution of wood properties within the tree is essential for understanding tree physiology as well as for biomass estimations and for assessing the quality of wood products.? Aims
The radial and vertical variations of basic specific gravity (BSG) and relative water content of lumens (RWC L ) were studied for five species: Quercus petraea/robur, Fagus sylvatica, Acer pseudoplatanus, Abies alba and Pseudotsuga menziesii. The observations were compared with typical patterns of variations reported in the literature.? Methods
Wood discs were sampled regularly along tree stems and X-rayed in their fresh and oven-dry states.? Results
At breast height, BSG was found to clearly increase radially (pith to bark) for two species and to decrease for one species. For F. sylvatica and A. alba, the radial variations of BSG were rather U-shaped, with in particular inner wood areas showing respectively lower and higher BSG than the corresponding mature wood. RWC L increased generally from inner to outer area but wet sapwood was clearly distinguishable only for the coniferous species. Vertical variations of BSG and RWC L were strongly dependant on the species with usually non-linear patterns.? Conclusion
The observed variations of BSG were only partially in agreement with the reported typical radial patterns. Despite the vertical variations, the mean BSG of a cross-section at breast height appeared to be a good estimator of the mean BSG of the whole stem (although the difference was statistically significant for coniferous species), whereas breast height measurement of RWC L was not representative of the whole stem.11.
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Robert Schneider Martin Riopel David Pothier Lévis Côté 《Annals of Forest Science》2008,65(6):608-608
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Context
Information about variations in basic density (BD) and carbon content (%C) along tree stems is key to assessing forest carbon sinks.Aims
The aim of the study was to determine any differences in %C and BD between different woody tissues (bark, sapwood and heartwood) in two widespread European oak species (Quercus pyrenaica and Quercus petraea).Methods
Twenty trees were felled in northern Spain, and 317 discs cut from the trees were dried and analysed to determine %C and BD.Results
There were significant differences in %C between bark, heartwood and sapwood, and between species. There were also significant differences in BD between the tissues (heartwood?>?sapwood?>?bark), and the BD was higher in Q. petraea than in Q. pyrenaica. Both %C and BD varied along the stem.Conclusion
More accurate estimates of carbon contents were obtained by using specific values for different heights and anatomical parts, than by using single values. 相似文献19.
Jan Suszka Beata P. Plitta Marcin Michalak Barbara Bujarska-Borkowska Tadeusz Tylkowski Paweł Chmielarz 《Annals of Forest Science》2014,71(5):543-549