scholarly journals Wood Density and Ring Width in Quercus rotundifolia Trees in Southern Portugal

Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1499
Author(s):  
Vicelina Sousa ◽  
Maria Emília Silva ◽  
José Luís Louzada ◽  
Helena Pereira

Quercus rotundifolia Lam., known as holm oak or evergreen oak, occurs naturally in the western Mediterranean region, mainly as part of the agroforestry or agrosilvopastoral systems in Portugal (“montado”) and Spain (“dehesa”), and is economically important for acorn production. Less attention has been given to Q. rotundifolia wood, and its density variability is not known, namely related to tree growth. The wood density of 20 Q. rotundifolia trees was measured along the radial direction by X-ray densitometry and the factors responsible for ring width and wood density variation within and between trees were investigated at two sites located within the main species region in southern Portugal. Ring width was significantly different between sites, with an average of 1.81 mm and 1.55 mm. Wood density was very high and averaged between 888 kg/m3 and 914 kg/m3 but not significantly different between sites. Ring width and wood density showed a positive and significant correlation at both sites. Cambial age was the main source of variation for ring width and wood density, while between-tree effects accounted for a considerable proportion of wood density variation. The results are an important contribution for the species valorisation aiming at high-value wood products, also adding knowledge on the species growth of interest for tree selection and sustainable management.

2011 ◽  
Vol 41 (6) ◽  
pp. 1212-1219 ◽  
Author(s):  
Sofia Knapic ◽  
José L. Louzada ◽  
Helena Pereira

The wood of Quercus faginea Lam. was studied regarding its density variation within and between trees using microdensitometry techniques in 10 trees growing in northern Portugal. The observations were made in mature trees at several height levels (stem base and 1.3, 3.4, 5.5, 7.6, and 9.7 m). Variance analysis was done considering the core cylinder (first 15 rings) and the sheath (last 10 rings) in relation to tree, height level, and ring effects and their interactions. The wood revealed a high mean density of 0.848 g·cm–3 with small differences between earlywood and latewood (0.717 and 0.908 g·cm–3, respectively). Latewood corresponded on average to 66% of the total ring width, which averaged 2.4 mm. Wood density decreased with height and radially from pith to cambium. However, within-tree variation was of very moderate magnitude although higher for juvenile wood. Variation between trees was also small (6% coefficient of variation of the mean) and higher for the mature wood. Quercus faginea wood compares favourably with other oak species with regard to density characteristics and may be considered for production of quality solid wood products.


Holzforschung ◽  
1999 ◽  
Vol 53 (2) ◽  
pp. 199-203 ◽  
Author(s):  
M. P. Denne ◽  
C. M. Cahalan ◽  
D. P. Aebischer

Summary To assess the likely effects of silvicultural treatment on the wood quality of Nothofagus nervosa grown in the UK, and the possibilities of independent selection within seed origins for density and growth rate, ring width and wood density were analysed from pith to bark of 19 trees. Variations in vessel lumen size, vessel number mm−2, and total lumen area mm−2 were analysed in ten trees. Since density increased by only 0.005g cm−3 per mm increase in ring width, silvicultural practices such as initial spacing and thinning are not likely to have a substantial effect on the wood density of rauli. Similarly, variation in density with cambial age was significant but relatively minor in the 40- and 60-year old trees of the present sample, suggesting that the rotation length is unlikely to have any practical influence on the density of rauli. Considerable between-tree differences in density were found which did not correspond to differences in ring width, suggesting it should be feasible to select independently for density and growth rate. These differences in density were associated with differences in both vessel lumen size and vessel number mm−2


Forests ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 452 ◽  
Author(s):  
A. Correa-Díaz ◽  
A. Gómez-Guerrero ◽  
J. J. Vargas-Hernández ◽  
P. Rozenberg ◽  
W. R. Horwath

Ongoing climate variability strongly affects high-elevation forests, influencing the wood formation process (e.g., xylogenesis). Furthermore, spatio-temporal studies to establish links of wood properties and tree performance are needed. Using linear mixed-effects models, empirical cumulative distribution functions, and spatial analysis, we explore time trends and space connections of wood density of Pinus hartwegii Lindl. to remotely sensed variables (Moderate Resolution Imaging Spectro-radiometer MODIS-derived) in two high-elevation forests in México, Tláloc (TLA) and Jocotitlán (JOC) Mountains. Results indicated that elevation and cambial age effects are important factors explaining wood density variation. Minimum earlywood—MID, average—AVE, and maximum latewood density—MXD were statistically similar between mountains (p > 0.05), but TLA showed a significant increase in MID over time with higher values after 1950. Wood density values and spatial correlations were site-dependent with TLA exhibiting the highest correlations between MXD and the Normalized Difference Vegetation Index (NDVI) of the spring season (r = 0.59, p < 0.05). Overall, correlations to remotely sensed information were positive with MXD, negative for MID and divergent for AVE. Historical temperature defines MID along the elevation gradient, while MXD was related to soil moisture only at low-elevation sites where soils are deeper. We found that two high-elevation forests, 115 km away from each other, with similar climate, soil, and vegetation, behaved differently regarding their xylogenesis, indicating the potential of using the link between wood micro-density and remotely sensed information to understand forest response to climate change effects.


2013 ◽  
Vol 70 (5) ◽  
pp. 525-534 ◽  
Author(s):  
Miloš Ivković ◽  
Washington Gapare ◽  
Harry Wu ◽  
Sergio Espinoza ◽  
Philippe Rozenberg

1994 ◽  
Vol 24 (9) ◽  
pp. 1818-1823 ◽  
Author(s):  
S.Y. Zhang ◽  
G. Nepveu ◽  
R. Eyono Owoundi

Twenty-three trees of European oak (Quercuspetraea (Matt) Liebl. and Quercusrobur L.) were collected from northeastern France to study intratree and intertree variation in the following characteristics: (i) wood density as well as earlywood density and latewood density; (ii) various types of wood shrinkage; and (iii) ring width and its components. Both intratree variation and intertree variation in the three characteristics are significant, but intertree variation is generally smaller. However, the relative magnitude of intertree variation varies with characteristic: intertree variation accounts for about 40% of the total variation in radial, tangential, and volumetric wood shrinkage, 32.5% of the total variation in ring width, and 12.6% of the total variation in wood density. Furthermore, the intertree variation is closely and positively related to the intratree variation: among the three characteristics studied, both intertree variation and intratree variation were highest for ring width and its components, and lowest for wood density and its components. In addition, intratree variation increased remarkably with increasing tree age in these species. In general, intratree variation in wood density and wood shrinkage depends more on cambial age than on ring width. The present study, together with the information available so far, suggests that the quality of European oak wood could be significantly improved.


Trees ◽  
2013 ◽  
Vol 27 (4) ◽  
pp. 913-925 ◽  
Author(s):  
Tony Franceschini ◽  
Fleur Longuetaud ◽  
Jean-Daniel Bontemps ◽  
Olivier Bouriaud ◽  
Benoît-Damien Caritey ◽  
...  

2018 ◽  
Vol 48 ◽  
pp. 40-51 ◽  
Author(s):  
Astrid Vannoppen ◽  
Pascal Boeckx ◽  
Tom De Mil ◽  
Vincent Kint ◽  
Quentin Ponette ◽  
...  

2014 ◽  
Vol 44 (2) ◽  
pp. 136-144 ◽  
Author(s):  
Riikka Piispanen ◽  
Jaakko Heinonen ◽  
Sauli Valkonen ◽  
Harri Mäkinen ◽  
Sven-Olof Lundqvist ◽  
...  

This study focused on wood density and annual ring width in Norway spruce (Picea abies (L.) Karst.) grown in uneven-aged stands (UAS). In total, 96 trees were harvested from five UAS that had been managed by single-tree selection for decades. A data set of 27 trees from even-aged stands (EAS) was used for comparison. In the UAS trees, high density and narrow annual rings were found in the juvenile wood near the pith. Thereafter, wood density rapidly decreased until the 20th annual ring, followed by an increase toward the bark. In the outermost rings, wood density again slightly decreased. The trends in wood density in the UAS trees correspond with those reported for naturally regenerated, even-aged Norway spruce stands, with the exception of the decrease in the outermost rings. A mixed linear model with ring width, cambial age, and canopy position as fixed parameters accounted for 53% of the variation in wood density of the UAS trees. In contrast to UAS trees, EAS trees showed increased wood density in the outer rings as a result of decreasing growth rate. The abrupt change in wood density of UAS trees may affect the properties of timber sawn close to the pith.


1993 ◽  
Vol 23 (12) ◽  
pp. 2587-2593 ◽  
Author(s):  
Shu-Yin Zhang ◽  
Ruben Eyono Owoundi ◽  
Gérard Nepveu ◽  
Frédéric Mothe ◽  
Jean-François Dhôte

Wood density in relation to cambial age and ring width was studied in 23 trees of European oak (Quercuspetraea (Matt) Liebl. and Quercusrobur L.) from northeast France, and based on these relationships, a model predicting intratree wood density through cambial age and ring width was developed. Wood density is closely correlated with both cambial age and ring width, but its relationships with cambial age and ring width, to some extent, vary from tree to tree. The variation, however, does not show an appreciable pattern with tree height. The model developed is able to predict satisfactorily the average wood density of growth rings in European oak, and to explain the main part of the variation in wood density of individual trees. Furthermore, the model appears also possible to predict the average density of a given small piece of wood from any part of the merchantable bole of the trees. A general model, however, accounts for a relatively low percentage of the variation because there is large intertree variability of wood density in the species. The simulation results reveal that the dynamic silviculture applied to European oak might result in the production of denser and more uniform (in the sense of the radial variation of wood density) wood, compared with classical silviculture.


2018 ◽  
Vol 64 (No. 3) ◽  
pp. 101-107
Author(s):  
Foti Dafni ◽  
Passialis Costas ◽  
Voulgaridis Elias ◽  
Skaltsoyiannes Apostolos ◽  
Tsaktsira Maria

Wood density, tracheid length and growth rate were measured in Aleppo pine scions, 21–23 years old, and in Brutia pine rootstocks. In regard to the relationship between cambial age and dry density the results showed that the density increased with cambial age in both scions and rootstocks while the differences between Aleppo pine and Brutia pine were small. The relationship between cambial age and tracheid length showed an increase of tracheid length with cambial age. Differences between scions and rootstocks were small. From the last relationship it can be extracted that juvenile wood is produced in both scions and rootstocks although the Aleppo pine branches which were used for grafting were genetically matured. Between ring width and dry density and between ring width and tracheid length no statistical correlations were found either in scions or in rootstocks. The tracheid length in mature wood was higher than in juvenile wood. An increase of tracheid length with ring width was observed only in the case of juvenile wood.


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