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1.
Alexander Berrocal Johana Gaitan-Alvarez Roger Moya David Fernandez-Solis Edgar Ortiz-Malavassi 《林业研究》2020,31(2):667-676
To elucidate the development of heartwood,bark,sapwood,pith and specific gravity of wood in fastgrowing teak(Tectona grandis)plantations in Costa Rica,we sampled three trees in each of 55 plantations and modelled each variable with age,site and different tree heights.Age and stand density of plantations were significant correlated with stem diameter at breast height and total height of the tree.Formation of heartwood was initiated at the age of 4-year-old and increased in direct proportion with age.The age of plantation had a significant relationship with stem diameter at breast height,heartwood percentage,sapwood thickness,sapwood percentage,percentage of bark,pith diameter and percentage,and specify gravity.The model for these tree parameters was model with these parameters as dependent variable and in relation to age as independent variable. 相似文献
2.
《Scandinavian Journal of Forest Research》2012,27(1):41-53
Abstract This study focused on the amount of sapwood and its variation by means of computed tomographic (CT) imaging. Twenty-four trees were selected from four Norway spruce [Picea abies (L.) Karst.] stands in north-eastern France, varying in age, density and fertility. In each stand, sampled trees represented the dominant, co-dominant and suppressed strata. The heartwood/sapwood boundary was detected from the CT images, and the heartwood and sapwood amount and their variations were then evaluated. At the within-tree level sapwood width was relatively constant along the tree stem above the butt swelling and below the living crown. The between-tree sapwood width variations were partially explained by the total cross-sectional area of living branches. This result opens up the possibility of investigating within-tree allometric relationships. Sapwood width was found to be highly correlated with tree slendemess (tree height/breast height diameter) and with the relative height of the crown. This suggests that sapwood width could be readily predicted from conventional forest inventory measurements. The number of sapwood rings within the stem was largely dependent on cambial age, and could be determined dynamically using the concept of mean lifetime of sapwood rings. 相似文献
3.
Isabel Miranda Jorge Gominho Clara Araújo Helena Pereira 《European Journal of Forest Research》2014,133(1):81-87
Thirty families of Eucalyptus globulus L., established in a first-generation open-pollinated progeny test, were evaluated for the production of heartwood. Five trees of each family were harvested at 9 years of age, total tree height was measured and a cross-sectional disc was removed at 25 % stem height to estimate the amount of heartwood. The heartwood proportion of the stemwood cross-sectional area averaged 41 % with significant between-family variation (P = 0.016) ranging from 27 to 53 %. There were also important within-family differences with coefficients of variation of the mean between 4 and 48 %. Moderate heritability values were obtained for heartwood diameter and proportion (h 2 = 0.31 and 0.23, respectively) but low estimates were found for sapwood width (h 2 = 0.17). Strong positive genetic and phenotypic correlations of heartwood diameter were found with stem DBH and with heartwood proportion. Both correlation estimates indicated that larger trees tended to have more heartwood. The results indicate that there is an opportunity to reduce heartwood content in E. globulus through selection and breeding. 相似文献
4.
We evaluated heartwood, sapwood and bark content in teak trees. A total of 27 sample plots were laid out in teak plantations raised by State Forest Department in Karnataka covering different age groups... 相似文献
5.
We studied heartwood and sapwood variation in western redcedar (Thuja plicata) at three sites, including a 95-year-old naturally regenerated, unmanaged stand, a 35-year-old planted spacing trial, and a 30-year-old naturally regenerated stand to which thinning and fertilization treatments had been applied. In the 95-year-old stand, we studied within-tree variation in heartwood and sapwood. In the thinning/fertilization trial and the planted spacing trial, we studied effects of cultural practices and growth rate on heartwood and sapwood. In the trees that we studied, sapwood width was generally fairly narrow, rarely exceeding 3.5 cm. Heartwood formation in western redcedar appeared to begin at a relatively small stem diameter (7 cm) and at a young age, probably 10–15 years. The amount and proportion of heartwood increased with distance downward from the top of the tree, with the implication that older trees will contain a greater proportion of heartwood than younger trees. For any given age, it appears that cultural treatments that favor rapid growth will result in stems with greater amounts of both sapwood and heartwood, and a greater proportion of heartwood. 相似文献
6.
The development of heartwood and sapwood in maritime pine (Pinus pinaster Ait.) in relation with tree and cambial age and growth rate was studied in ten trees randomly sampled at harvest (54–85-year-old) in a commercial stand in central Portugal. Average ring width at stem base was 1.84 ± 0.34 mm for 50 years of age. Growth rate decreased with cambial age and for the same cambial age increased along the stem with tree height.
The number of heartwood rings was strongly correlated with cambial age. Heartwood formation was estimated to start at approximately 21 years of age and to proceed at a constant annual rate that increased with age (0.5 and 0.7 rings year−1 below and above 50 years of age). Within the tree, heartwood decreased with stem height, but in the lower part of the stem two patterns of variation were shown: a continuous decrease or an increase from stem base to a maximum at 2–3 m and a decrease afterwards. Sapwood radial width remained approximately constant within the tree and correlated positively with tree growth. 相似文献
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8.
The variation in extractives content in sapwood and heartwood was investigated among 12 trees in each of four commercial plantations of Eucalyptus globulus in central Portugal. The study was carried out at the 15% height level and extractions used successively dichloromethane, ethanol and water. At all sites, heartwood had significantly more extractives than sapwood, on average 3.8 and 2.4%, respectively. Most extractives consisted of ethanol soluble material (on average 52% of total extractives). Among the sites, there was a statistically significant difference in the content of extractives but the most important source of variation was the within-tree variation between sapwood and heartwood. Differences in the content of extractives were also observed among trees. A strong relation between extractives content and heartwood proportion was found. The potential loss of pulp yield and problems associated with accumulation of extractives are directly related to the heartwood proportion in the eucalypt stems. Forest management should take into account heartwood development and selection for minimising heartwood extractives. 相似文献
9.
Sofia Knapic Vanda Oliveira Marika Makkonen Isabel Pinto-Seppä Helena Pereira 《European Journal of Forest Research》2014,133(6):1007-1014
Maritime pine (Pinus pinaster Ait.) is an important timber and pulpwood species covering about 4 million ha in Portugal, Spain and France. This work studied the cross-sectional distribution of heartwood and sapwood along the stem using 3D modelling on 20 trees. The target was to assess the potential of this species for the industrial production of heartwood sawn products. The maritime pine stems were characterized by wide sapwood of 10 cm, in average, and the presence of heartwood at all height levels with constant diameter up to 35 % tree height, decreasing afterwards. In the radial section, the heartwood follows a circumferential-like shape which changes along the stem. Pith eccentricity index values were low and homogeneous regarding to stem and higher for heartwood. Heartwood cross-sectional shape was constant up to 45 % of total height of the tree and more elongated upwards. The constant heartwood diameter, low taper and pith eccentricity index, and an approximate circular shape up to 10 m height indicated these species’ potential to produce solid wood products made out of heartwood. 相似文献
10.
J. Wilkes 《Wood Science and Technology》1991,25(2):85-90
Summary The rate of heartwood development was examined at four heights in stems of Pinus radiata D. Don from 18 mature stands in south-eastern Australia. While the diameter of heartwood tended to be greatest at stump and breast heights, formation commenced earlier (i.e. with fewer sapwood rings) and/or progressed more rapidly 10–20 m above ground level. Appreciable variation in heartwood development was detected between trees in the same and different stands, with both environmental and genetic factors apparently important. Regression analyses involving three parameters of heartwood development (number of rings, diameter and percentage area) and stem characteristics including height, diameter and ring width suggested that heartwood formation is affected little by tree vigour in the post-juvenile growth phase. Rather it seems that the rate at which annual increments are included in heartwood is largely fixed for any particular height level and stem. Thus the amount (but not necessarily the percentage) or heartwood in a stem is substantially dependent on diameter growth early in tree life.The expert technical assistance of Mr. R. Colley is gratefully acknowledged. Valuable assistance in the measurement of heartwood dimensions was also provided by Ms. V. Kurz and Mr. C. Slatyer. Dr. R. K. Bamber and Mr. A. P. Wilkins offered particularly helpful advice 相似文献
11.
Stephen C. Sillett Robert Van Pelt George W. Koch Anthony R. Ambrose Allyson L. Carroll Marie E. Antoine Brett M. Mifsud 《Forest Ecology and Management》2010
How long forest trees can sustain wood production with increasing age remains an open question, primarily because whole-crown structure and growth cannot be readily measured from the ground or on felled trees. We climbed and directly measured crown structures and growth rates of 43 un-suppressed individuals (site trees) of the two tallest species – Eucalyptus regnans and Sequoia sempervirens – representing a wide range of tree sizes and ages. In both species, ground-level measurements of annual growth, including height, ring width, and basal area increment, exhibited the oft-reported trend of decreasing growth (or no change in growth) with age, yet wood production of the entire main trunk and whole crown both increased with size and age up to and including the largest and oldest trees we measured. The balance between structural metrics of whole-crown respiratory demands (cambium area, inner bark volume, sapwood volume, and heartwood deposition area) and photosynthetic capacity (leaf area and green bark area) was statistically independent of size but not age. After accounting for the effect of size, trees with lower potential respiratory demands grew more than trees with higher potential respiratory demands per unit photosynthetic area. The strongest determinant of tree energy balance was the ratio of aboveground cambium area to leaf area. Among the site trees we examined, over 85% of the variation in annual wood production was explained by variation in size, and the proportion of total aboveground wood production in appendages (branches, limbs, and reiterated trunks) increased linearly with size. With increasing age in both species, the proportion of annual wood production converted to heartwood increased in main trunks and appendages. The oldest tree we measured produced more heartwood in its main trunk over 651 years (351 m3) than contained in any tree we measured <1500 years old. The two tallest tree species achieve similar stature despite divergent growth dynamics and ecologies. At one extreme, E. regnans attains great size quickly but dies relatively young because trees are susceptible to fire and fungi. At the other extreme, S. sempervirens attains great size more slowly but has a long lifespan because trees resist fire and prioritize investment in decay-resistant heartwood. Increasing wood production as trees age is a mechanism underlying the maintenance of biomass accumulation during forest development and the carbon-sink capacity of old-growth forests. 相似文献
12.
Leaf area is commonly estimated as a function of sapwood area. However, because sapwood changes to heartwood over time, it has not previously been possible to reconstruct either the sapwood area or the leaf area of older trees into the past. In this study, we report a method for reconstructing the development of the sapwood area of dominant and codominant balsam fir (Abies balsamea (L.) Mill.). The technique is based on establishing a species-specific relationship between the number of annual growth rings in the sapwood area and tree age. Because the number of annual growth rings in the sapwood of balsam fir at a given age was found to be independent of site quality and stand density, the number of rings in sapwood (NRS) can be predicted from the age of a tree thus: NRS = 14.818 (1 - e(-0.031 age)), unweighted R(2) = 0.80, and NRS = 2.490 (1 - e(-0.038 age)), unweighted R(2) = 0.64, for measurements at breast height and at the base of the live crown, respectively. These nonlinear asymptotic regression models based only on age, were not improved by adding other tree variables such as diameter at breast height, diameter at the base of the live crown, total tree height or percent live crown. 相似文献
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14.
Ana Lourenço Isabel Baptista Jorge Gominho Helena Pereira 《Journal of Wood Science》2008,54(6):464-469
The pulping wood quality of Acacia melanoxylon was evaluated in relation to the presence of heartwood. The sapwood and heartwood from 20 trees from four sites in Portugal
were evaluated separately at 5% stem height level in terms of chemical composition and kraft pulping aptitude. Heartwood had
more extractives than sapwood ranging from 7.4% to 9.5% and from 4.0% to 4.2%, respectively, and with a heartwood-to-sapwood
ratio for extractives ranging from 1.9 to 2.3. The major component of heartwood extractives was made up of ethanol-soluble
compounds (70% of total extractives). Lignin content was similar in sapwood and heartwood (21.5% and 20.7%, respectively)
as well as the sugar composition. Site did not influence the chemical composition. Pulping heartwood differed from sapwood
in chemical and optical terms: lower values of pulp yield (53% vs 56% respectively), higher kappa number (11 vs. 7), and lower
brightness (28% vs 49%). Acacia melanoxylon wood showed an overall good pulping aptitude, but the presence of heartwood should be taken into account because it decreases
the raw-material quality for pulping. Heartwood content should therefore be considered as a quality variable when using A. melanoxylon wood in pulp industries 相似文献
15.
Time series of carbon fluxes in individual Scots pine (Pinus sylvestris L.) trees were constructed based on biomass measurements and information about component-specific turnover and respiration rates. Foliage, branch, stem sapwood, heartwood and bark components of aboveground biomass were measured in 117 trees sampled from 17 stands varying in age, density and site fertility. A subsample of 32 trees was measured for belowground biomass excluding fine roots. Biomass of fine roots was estimated from the results of an earlier study. Statistical models were constructed to predict dry mass (DW) of components from tree height and basal area, and time derivatives of these models were used to estimate biomass increments from height growth and basal area growth. Biomass growth (G) was estimated by adding estimated biomass turnover rates to increments, and gross photosynthetic production (P) was estimated by adding estimated component respiration rates to growth. The method, which predicts the time course of G, P and biomass increment in individual trees as functions of height growth and basal area growth, was applied to eight example trees representing different dominance positions and site fertilities. Estimated G and P of the example trees varied with competition, site fertility and tree height, reaching maximum values of 22 and 43 kg(DW) year(-1), respectively. The site types did not show marked differences in productivity of trees of the same height, although height growth was greater on the fertile site. The G:P ratio decreased with tree height from 65 to 45%. Growth allocation to needles and branches increased with increasing dominance, whereas growth allocation to the stem decreased. Growth allocation to branches decreased and growth allocation to coarse roots increased with increasing tree size. Trees at the poor site allocated 49% more to fine roots than trees at the fertile site. The belowground parts accounted for 25 to 55% of annual G, increasing with tree size and decreasing with site fertility. Annual G and P per unit needle mass varied over the ranges 1.9-2.4 and 3.5-4.0 kg(DW) kg(-1), respectively. The relationship between P and needle mass in the example trees was linear and relatively independent of competition, site fertility and age. 相似文献
16.
Aleš Kadunc 《European Journal of Forest Research》2007,126(3):349-358
Sycamore (Acer pseudoplatanus L.) is a tree species with highly valuable wood. Similar to European beech (Fagus sylvatica L.), the stemwood of sycamore can be devalued due to the discolouration i.e. brown heart (hearwood discolouration, hereafter).
This paper aims to establish the influence of tree traits and site characteristics on the formation of heartwood discolouration
and the possibility of predicting the occurrence of heartwood discolouration. For this purpose, 351 sycamore trees from 38
sites in Slovenia, most of them on carbonate bedrock and in the mountain vegetation belt, were analysed. Stem analysis was
carried out on all the trees and the age, diameter at breast height (dbh), height of crown base, forking and crown size, were
established. On the stump and upper fronts of the first and second logs, the maximum heartwood discolouration diameter was
measured. Using logistic regression, the positive influence of age, relative crown length and average diameter increment on
the formation of heartwood discolouration was ascertained. Conversely, the probability of heartwood discolouration was diminished
by diameter increment in the last 20 years. In the less productive sites, the probability of formation of heartwood discolouration
was relatively high in small diameter trees, but it increased slowly with diameter. Tree forking also contributed to a large
extent of the heartwood discolouration. After the diameter at breast height achieves 45 cm, the formation of heartwood discolouration
on the first log is highly probable. As in beech, the heartwood discolouration increases along the stem axis up to a height
of 6–8 m, and decreases in the higher parts of the tree. 相似文献
17.
Douglas-fir (Pseudotsuga menziesii) is one of the best timber conifers providing long sawnwood components. Original from North America, it has been planted in Europe on approximately 550 thousand ha. Twenty Douglas-fir trees growing in two sites in Portugal were studied regarding ring analysis, heartwood, sapwood and bark development, and taper. The radial growth rate was 7.1 and 6.6 mm year−1 at stem base for 45- and 50-year-old trees, respectively, in the two sites. Initial growth rate was slower, increasing until about 20 years and decreasing afterwards. Heartwood proportion represented on average 49% of the cross section in the lower part of the stem and decreased upwards. Heartwood formation was estimated to start at a cambial age of 8–9 years and increasing by 0.7–0.9 rings year−1. Sapwood width was on average 75 mm at stem base, decreasing upwards. Bark was 26–27 mm thick at stem base, where it represented 15% of the cross-sectional area and decreased to 3–5 mm at the top. Stemwood and heartwood tapers were on average 15 mm m−1 in the lower stem part and 21 and 18 mm m−1, respectively, in the upper part. Douglas-fir showed a good potential for the mountain areas of Portugal, and under the silvicultural conditions of both stands the trees presented ring homogeneity, small conicity and low taper suitable for long wood components.
相似文献18.
Tropical moist forests are notable for their richness in tree species. The presence of such a diverse tree flora presents potential problems for scaling up estimates of water use from individual trees to entire stands and for drawing generalizations about physiological regulation of water use in tropical trees. We measured sapwood area or sap flow, or both, in 27 co-occurring canopy species in a Panamanian forest to determine the extent to which relationships between tree size, sapwood area and sap flow were species-specific, or whether they were constrained by universal functional relationships between tree size, conducting xylem area, and water use. For the 24 species in which active xylem area was estimated over a range of size classes, diameter at breast height (DBH) accounted for 98% of the variation in sapwood area and 67% of the variation in sapwood depth when data for all species were combined. The DBH alone also accounted for > or = 90% of the variation in both maximum and total daily sap flux density in the outermost 2 cm of sapwood for all species taken together. Maximum sap flux density measured near the base of the tree occurred at about 1,400 h in the largest trees and 1,130 h in the smallest trees studied, and DBH accounted for 93% of the variation in the time of day at which maximum sap flow occurred. The shared relationship between tree size and time of maximum sap flow at the base of the tree suggests that a common relationship between diurnal stem water storage capacity and tree size existed. These results are consistent with a recent hypothesis that allometric scaling of plant vascular systems, and therefore water use, is universal. 相似文献
19.
Wei Wang Yuichi Hanai Chisato Takenaka Rie Tomioka Kazuya Iizuka Hajime Ozawa 《Journal of Forest Research》2016,21(5):251-258
Absorption of radiocesium (137Cs and 134Cs) through bark, and its subsequent translocation into wood and needles, has been suggested as a potential source of tree contamination, but the process is not well understood. Field experiments were conducted to confirm whether Cs could enter a Japanese cedar tree through the bark and how Cs moves within a tree. Stable Cs (133Cs) was applied to the bark at 1.2-m height on 10- and 26-year-old Japanese cedars. The 133Cs concentrations were determined in the bark, sapwood, and heartwood (for 26-year-old cedar only) of stem disks from several heights, as well as in current-year needles from the canopy. The 133Cs concentrations were considerably higher in the sapwood and heartwood of stem disks from 1.2-m height in treated trees than in untreated trees, suggesting that 133Cs penetrated the bark to enter the wood. The average 133Cs concentrations were higher in the heartwood than the sapwood, indicating 133Cs accumulation in the heartwood. High 133Cs concentrations in the needles of treated trees implied acropetal movement of 133Cs to actively growing organs. Our results demonstrate that Cs can enter Japanese cedar trees through the bark and that Cs is transported radially to the heartwood and vertically to the apex. 相似文献
20.
Scots pine (Pinus sylvestris) sapwood was investigated for variation in treatability using the wood modifying agent, furfuryl alcohol (FA) in water. The
variation in treatability within trees, between trees and between different stands of Scots pine was studied. Investigated
variables that reduced the residual variance significantly were: site location, latitude of site, height of trees, annual
ring width, vertical and horizontal position in the tree and method of drying. Linear mixed model statistics were used and
tree number was handled as a random variable. The best model reduced the treatability residual variance by 67%. Location was
the single factor affecting treatability most. Differences in latitude between locations may be the reason for that. Latitude
correlated negatively with the treatability. Within the trees, the treatability of sapwood increased with distance from ground
and with distance from heartwood border. A small, but significantly better treatability was found for kiln dried wood (60°C)
compared to air dried wood (20°C). 相似文献