共查询到20条相似文献,搜索用时 31 毫秒
1.
Andreas Gruber Jolanda Zimmermann Gerhard Wieser Walter Oberhuber 《Annals of Forest Science》2009,66(5):503-503
2.
Miloš Ivković Washington Gapare Harry Wu Sergio Espinoza Philippe Rozenberg 《Annals of Forest Science》2013,70(5):525-534
? Context
The correlation between tree ring width and density and short-term climate fluctuations may be a useful tool for predicting response of wood formation process to long-term climate change.? Aims
This study examined these correlations for different radiata pine genotypes and aimed at detecting potential genotype by climate interactions.? Methods
Four data sets comprising ring width and density of half- and full-sib radiata pine families were used. Correlations with climate variables were examined, after the extraction of the effect of cambial age.? Results
Cambial age explained the highest proportion of the ring to ring variation in all variables. Calendar year and year by family interaction explained a smaller but significant proportion of the variation. Rainfall had a positive correlation with ring width and, depending on test site, either a negative or positive correlation with ring density. Correlations between temperature during growing season and ring density were generally negative.? Conclusion
Climate variables that influence ring width and wood density can be identified from ring profiles, after removing the cambial age effect. Families can be selected that consistently show desirable response to climate features expected to become prevalent as a result of climate change. 相似文献3.
Models for predicting microfibril angle variation in Scots pine 总被引:1,自引:0,他引:1
David Auty Barry A. Gardiner Alexis Achim John R. Moore Andrew D. Cameron 《Annals of Forest Science》2013,70(2):209-218
Context
Microfibril angle (MFA) is one of the key determinants of solid timber performance due to its strong influence on the stiffness, strength, shrinkage properties and dimensional stability of wood.Aims
The aim of this study was to develop a model for predicting MFA variation in plantation-grown Scots pine (Pinus sylvestris L). A specific objective was to quantify the additional influence of growth rate on the radial variation in MFA.Methods
Twenty-three trees were sampled from four mature Scots pine stands in Scotland, UK. Pith-to-bark MFA profiles were obtained on 69 radial samples using scanning X-ray diffractometry. A nonlinear mixed-effects model based on a modified Michaelis–Menten equation was developed using cambial age and annual ring width as explanatory variables.Results
The largest source of variation in MFA (>90 %) was within trees, while between-tree variation represented just 7 % of the total. Microfibril angle decreased rapidly near the pith before reaching stable values in later annual rings. The effect of ring width on MFA was greater at higher cambial ages.Conclusion
A large proportion of the variation in MFA was explained by the fixed effects of cambial age and annual ring width. The final model is intended for integration into growth, yield and wood quality simulation systems. 相似文献4.
Context
The development of multiple trait selection indices for solid (structure) wood production in the Scots pine (Pinus sylvestris L.) breeding program requires genetic variances and covariances estimated among wood quality traits including stiffness.Aims
Genetic control and relationships among Scots pine growth, fiber, and wood quality traits were assessed by estimating heritability, phenotypic and genetic correlation using a Scots pine full-sib family trial.Method
Wood quality traits including clearwood and dynamic acoustic stiffness were measured using SilviScan and Hitman in a 40-year-old progeny trial and by sampling increment cores of 778 trees of 120 families. Genetic parameters were estimated using the mixed model by the ASReml software.Results
Heritability ranged from 0.147 to 0.306 for growth, earlywood, transition wood and latewood proportion traits and from 0.260 to 0.524 for fiber dimension, wood density, MFA and stiffness traits. The highly unfavorable genetic correlation between diameter and whole core density (?0.479) and clearwood stiffness (?0.506) and dynamic acoustic stiffness (?0.382) was observed in this study.Conclusion
The unfavorable genetic correlations between growth traits and stiffness indicate that multiple traits selection using optimal economic weights and optimal breeding strategies are recommended for the advanced Scots pine breeding program. 相似文献5.
Joana Vieira Sergio Rossi Filipe Campelo Cristina Nabais 《European Journal of Forest Research》2014,133(1):41-50
Neighboring trees growing under identical environmental conditions can exhibit different dynamics and periods of growth. Despite the recent advances in cambial biology, the exogenous and endogenous factors generating asynchronous xylem growths still remain undetermined. This study investigated timings and duration of xylem formation in maritime pine (Pinus pinaster Ait.) from an even-aged plantation in Portugal growing under Mediterranean climate. Cambial phenology and stem diameter were monitored weekly, from March to December 2010, on two classes of trees divided according to the tree ring widths of the last 15 years, but similar age and size: fast- and slow-growing trees. We tested the hypothesis that differences in tree ring widths result from cell production which in turn affects timings of xylogenesis and that the bimodal growth pattern, typical of the Mediterranean, originates from a double reactivation of the cambium: in spring and autumn. Cambial activity started earlier and ended later in fast-growing trees, confirming that cell production is a key factor determining the duration of xylogenesis. Intra-annual variations in stem diameter recorded by band dendrometers revealed two peaks of increment occurring in spring and late summer. However, the number of cambial cells did not increase in late summer, which suggested that the second peak of increment was caused by stem rehydration, rather than by a reactivation of cell division. These results demonstrated that the variability in the timings of xylem phenology observed among trees of the same age and size and growing under similar environmental conditions was closely related to cell production and not to age or size per se. 相似文献
6.
Félix P. Hartmann Cyrille B. K. Rathgeber Meriem Fournier Bruno Moulia 《Annals of Forest Science》2017,74(1):14
Key message
The emergence of the characteristic tree-ring pattern during xylogenesis is commonly thought to be controlled by a gradient of morphogen (auxin, TDIF peptide...). We show that this hypothesis accounts for several developmental aspects of wood formation, but not for the final anatomical structure.Context
Wood formation is a dynamic cellular process displaying three generic features: (i) meristematic cell proliferation is restricted to the small cambial zone, preventing exponential xylem radial growth along the growing season; (ii) developmental processes result in a stable zonation of the developing xylem; (iii) the resulting mature wood cells form the typical tree-ring structure made of early and late wood with a gradient of cell sizes, an important trait for wood functioning in trees and for lumber quality. The mechanisms producing these spatial-temporal patterns remain largely unknown. According to the often-cited morphogenetic-gradient hypothesis, a graded concentration profile of a signalling molecule (e.g. auxin, TDIF) controls xylogenesis by providing positional information to differentiating cells.Aims
We assessed the predictions of the morphogenetic-gradient theory.Methods
We developed a computational model of wood formation implementing hypotheses on how a morphogen flows through the developing xylem and controls cell division and growth and we tested it against data produced by studies monitoring wood formation in conifers.Results
We demonstrated that a morphogenetic gradient could indeed control xylem radial growth and wood-forming tissue zonation. However, it failed to explain the pattern of final cell sizes observed in tree-rings. We discussed the features that candidate additional regulatory mechanisms should meet.7.
Key message
Onset and cessation of radial and height increment of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) in southern Finland were independent phenomena. They both contributed to the increment period duration, which was a more crucial factor defining the magnitude of annual radial and height increment.Context
Phenology of diameter and height increment is a critical component of growth, also contributing to damage and survival of trees.Aims
We quantified annual variation in intra-annual tracheid production and height increment of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.).Methods
The number of tracheids and the day of the year for the onset and cessation of tracheid production were monitored from microcores collected repeatedly during growing seasons 2001–2012 in southern Finland. Weekly height increment was also measured in an adjacent sapling stand in 2008–2012.Results
The first tracheids in pine were found around mid-May and in spruce a week later. The cessation of the tracheid production occurred during the last week of August for both tree species. Increment onset and cessation were independent phenomena, both contributing to the magnitude of tracheid production via increment period duration, which appeared to be a more crucial factor defining the number of tracheids. Duration of the height increment period was also related to shoot length but the connection was less tight than the link between the duration of tracheid production and the number of tracheids. A thermal threshold around 100 d.d. (degree days) was found for the onset of radial increment. No single environmental factor triggered the cessation of tracheid production, but in some years, soil water availability appeared to play a role.Conclusion
The results indicate that extending growing seasons due to the climatic warming may increase growth in the Finnish forests.8.
Seasonal dynamics of wood formation: a comparison between pinning,microcoring and dendrometer measurements 总被引:1,自引:1,他引:0
Harri Mäkinen Jeong-Wook Seo Pekka Nöjd Uwe Schmitt Risto Jalkanen 《European Journal of Forest Research》2008,127(3):235-245
Three different methods were evaluated for analysing wood formation of Norway spruce [Picea abies (L.) Karst.] and Scots pine (Pinus sylvestris L.) in Finland. During two growing seasons, wood formation dynamics were determined both by wounding the cambium with a needle
followed by localisation of the wound-associated tissue modification after the growing season (pinning), and by extracting
small increment cores during the growing season (microcoring). Stem radius was additionally monitored with band dendrometers.
For Norway spruce, pinning and microcoring yielded similar dates for the onset of wood formation. The timing of wood production
during the growing season was also similar for pinning and microcoring. For Scots pine, the onset of wood formation was recorded
from microcores almost 2 weeks later than from pinning samples. In Scots pine, microcore measurements also produced somewhat
later cessation dates for tracheid formation than the pinning samples. For both tree species, the total number of tracheids
formed during the growing season was, however, about the same for pinning and microcoring. Dendrometer results clearly differed
from those of pinning and microcoring. In particular, the dendrometers showed an increase of stem radius considerably earlier
in spring, when the other methods did not detect wood formation. Thus, pinning and microcoring currently represent the most
reliable techniques for detailed monitoring of wood formation. 相似文献
9.
Models of the longitudinal distribution of ring area as a function of tree and stand attributes for four major Canadian conifers 总被引:1,自引:0,他引:1
Context
It is widely accepted that ring area increment generally increases from the tree apex to the crown base and is more-or-less constant below the crown base (Pressler’s law), but few quantitative models of this distribution have been developed.Aims
The aim of this study was to develop a model of ring area increment using easily obtained crown features and other tree or stand characteristics in order to further the understanding and prediction of tree growth, form, and wood quality.Methods
The models were fit to stem analysis observations from white spruce, black spruce, balsam fir, and lodgepole pine.Results
In the final model, which includes tree crown and stand variables, ring area increment within the crown region was slightly curvilinear, the slope of ring area increment below the crown was non-zero, and the effect of butt swell was appreciable up-to a relative height of 0.10.Conclusions
The high accuracy of the mixed effects model suggests that the three-component model form is appropriate for describing ring area profiles, whereas some tree-to-tree variation remains unexplained. The tree and stand variables used in these models can be easily measured in the field or obtained from remote sensing techniques. 相似文献10.
Using density management diagrams to assess crown fire potential in Pinus pinaster Ait. stands 总被引:1,自引:0,他引:1
Ibán Gómez-Vázquez Paulo M. Fernandes Manuel Arias-Rodil Marcos Barrio-Anta Fernando Castedo-Dorado 《Annals of Forest Science》2014,71(4):473-484
Context
Density management diagrams (DMDs) are useful for designing, displaying and evaluating alternative density management regimes for a given stand-level management objective. The inclusion of variables related to crown fire potential within DMDs has not previously been considered.Aims
The aim of this study was to include isolines of variables related to crown fire initiation and spread in DMDs to enable identification of stand structures associated with different types of wildfire.Methods
Biometric and fuel data from maritime pine (Pinus pinaster Ait.) stands in NW Spain were used to construct DMDs. Different surface and crown fire behaviour models were used together to estimate crown fire potential.Results
The crown fire potential varied greatly throughout development of the maritime pine stands. Low stands were more prone to crowning. The type of crown fire was mainly determined by stand density.Conclusion
The DMDs developed can be used to identify relationships between stand structure and crown fire potential, thus enabling the design of thinning schedules aimed at reducing the likelihood of crowning. 相似文献11.
Vladimír Račko František Kačík Oľga Mišíková Pavol Hlaváč Igor Čunderlík Jaroslav Ďurkovič 《Annals of Forest Science》2018,75(3):82
Key message
Fungal infection was outlined as a potential reason for the onset of indented annual growth ring formation during the juvenile phase of hazel wood growth. Annual growth ring indentations resulted from the formation of disturbed zones which originated solely in close proximity to leaf traces.Context
Hazel wood is an abnormal type of woody tissue that is formed as a result of exogenous stimuli that may trigger long-term responses in the cambium. Cambial responses produce anatomical alterations in the surrounding xylem tissue that can be observed as an indentation of annual growth rings. The chemical profiles of lignan hydroxymatairesinol may provide an indication of its possible role in the protection of a living tree against the spread of a fungal or microbial infection at the onset of indentation.Aims
The objectives of this study were to reveal the anatomical differences in the altered woody tissue of Picea abies hazel wood at both the onset and the later stages of annual growth ring indentation and to determine the chemical profiles for hydroxymatairesinol upon elicitation by a fungal infection in the disturbed zones.Methods
Light and scanning electron microscopy observations were carried out on radial, tangential, and cross sections of hazel wood zones separated from P. abies stems. Concentrations of hydroxymatairesinol were determined for both the disturbed zones and the non-indented zones using a gradient high-performance liquid chromatography.Results
The formation of disturbed zones was accompanied by significant changes in both the direction and width of the tracheids which produced an abnormal formation of intertwined and twisted tracheids. Fungal hyphae, radial cell wall cracks, and unusually large cross-field pitting were all found in the tracheids of the disturbed zones.Conclusion
The content of hydroxymatairesinol in the acetone extract determined from the disturbed zones was 3.4 times greater than that present in the non-disturbed tissues. By means of vascular dysfunction in the leaf traces, host trees responded to the fungal infection by plugging the lumens of conductive leaf trace tissue and filling the vascular pathway with polyphenolic compound deposits.12.
Shakti S. Chauhan Monika Sharma Jimmy Thomas Luis A. Apiolaza David A. Collings John C. F. Walker 《Annals of Forest Science》2013,70(4):439-449
? Introduction
There has been an increasing interest in very early selection of radiata pine to reduce the breeding cycle for solid wood products. For such selection, new approaches are required to assess wood quality in wood from very young stems.? Methods
Nursery seedlings of clones of radiata pine were grown in leant condition using two leaning strategies for 18–20 months. Opposite wood and compression wood were isolated from the leaning stems and tested for dynamic modulus of elasticity, density, longitudinal shrinkage, volumetric shrinkage and compression wood area using new methods evolved for testing small size samples quickly and reliably. The methods were tested for their efficiency in differentiating clones by their wood properties.? Results
Leaning of stems provided distinct opposite and compression wood for testing. Automated image analysis method used for compression wood area assessment was found to be a quick and effective method for processing large number of samples from young stems. Compression wood was characterised by high basic density, high longitudinal shrinkage and low volumetric shrinkage than that of opposite wood. Acoustic velocity in opposite wood had a strong negative association with longitudinal shrinkage. The study signifies the importance of preventing mixing of opposite wood with compression wood while assessing wood quality in young stems thus making leaning a critical strategy. The comparison of wood properties of opposite wood revealed significant differences between clones. Opposite wood of the clone with the lowest dynamic modulus of elasticity exhibited the highest longitudinal shrinkage.? Conclusion
Significant differences in measurable wood properties between clones suggest the prospects of early selection for solid wood products. 相似文献13.
14.
Eitaro Fukatsu Miyoko Tsubomura Yoshitake Fujisawa Ryogo Nakada 《Annals of Forest Science》2013,70(5):451-459
Context
Wood density is an important component of wood quality, and it is therefore important to assess whether it can be subject to genetic improvement.Aim and methods
We assessed the potential for genetic improvement of wood density in Larix kaempferi by recording components of annual growth rings. A full diallel mating test based on six plus L. kaempferi trees was used. Trees were 29 years old. Wood density was recorded by soft X-ray densitometry, and genetic parameters and genetic gains were computed.Results
Wood density of mature wood was highly heritable, and the largest heritability (0.78) was reached at age 25. Specific combining ability and reciprocal effects displayed very low variance. The age–age correlation of overall wood density was very high (>0.94). The genetic correlation between overall wood density and basal cross-sectional area was positive after age 10. Early selection at age 6 would account for 69 % of the genetic gain from direct selection at age 28 in terms of wood density.Conclusion
Genetic improvement of wood density could be achieved by mass selection and a simultaneous selection for radial increment in L. kaempferi; early selection for wood density can be achieved in this species. 相似文献15.
Daniel Moreno-Fernández Isabel Cañellas Rafael Calama Javier Gordo Mariola Sánchez-González 《Annals of Forest Science》2013,70(8):761-768
Context
Edible stone pine (Pinus pinea L.) nut is a forest product which provides the highest incomes to the owners of stone pine forests.Aim
The objective of this work is to evaluate the effect of first thinning on growth and cone production in an artificially regenerated stand in order to determine optimum intensity.Methods
A thinning trial was installed in 2004 to compare two thinning regimes (heavy and moderate) and a control treatment. From 2004 to 2012, six inventories of forest attributes were carried out, and the cone crop was harvested annually. We evaluated the effect of thinnings on growth using repeated measures analysis of variance with a mixed model approach. With regards to cone production, we first estimated the probability of finding cones in a tree by applying a generalized mixed model and then estimated cone production by using a mixed model, including climatic variables.Results
We found that thinning had a positive influence on tree diameter increment. Thinning increased the probability of finding cones and cone production. However, significant differences between heavy and moderate thinnings were not found.Conclusion
We recommend early silvicultural treatments in stone pine stands to favor the development of trees and larger edible pine nut production. 相似文献16.
Comparing needle and shoot phenology with xylem development on three conifer species in Italy 总被引:1,自引:0,他引:1
17.
Context
Although drought is generally considered the main environmental constraint in Mediterranean environments, the ability to acclimate to and tolerate frost in early developmental stages can be a determinant for seedling survival of many Mediterranean tree species like stone pine (Pinus pinea L.).Aims
The aim of this study was to assess the impact of the developmental stage of naturally regenerated stone pine individuals on tolerance to low temperature (LT) from summer to late autumn and in spring, at a highly continental site in central Spain. Specifically, we tested to what extent the differences in tolerance are related to shoot heteroblasty.Methods
We assessed LT tolerance of needles from individuals at three age classes (class C1: seedlings, class C2: 4- to 8-year-old saplings and class C3: >9-year-old saplings) over nine dates from summer to spring.Results
LT tolerance displayed severe seasonal trends and differed between age classes. It usually increased with sapling age. Such differences were tightly related to heteroblasty of the shoots. Our results point to a higher LT tolerance associated with larger leaf dry mass per unit area (LMA) values. No impact of late frosts on shoot growth rates was detected during this study.Conclusions
Developmental changes during early plant growth seem to play a role in frost tolerance of stone pine seedlings, a finding which furthers our understanding of regeneration dynamics in this species in areas with continental influence. 相似文献18.
? Context
The rising demand of energy wood for heating purposes in Germany leads to concerns regarding the overexploitation of forests. A major aspect is the impact of whole-tree harvesting on long-term productivity of forest soils.? Aims
This study aimed to analyze the effects of nutrient removal on productivity using the historically prevalent practice of litter raking. Since there is a lack of controlled whole-tree harvesting experiments in Germany, we used litter raking as a surrogate management practice entailing the removal of nutrients from forest stands.? Methods
We used three sites with documented litter raking to analyze the effects of nutrient removal on productivity using dendroecological methods: two recent litter removal experiments in two Scots pine stands (Siegenburg and Burglengenfeld) and one oak stand (Eichhall) with documented historic litter raking. Basal area increment (BAI) and tree-ring characteristics were compared between periods with litter raking and the preceding periods for both treatment and control plots.? Results
For the two Scots pine sites with a relatively short litter raking period, no effects of litter raking on BAI could be ascribed to nutrient removal. On the oak site with a longer history of litter utilization, the loss in BAI due to litter raking amounts to 22 % during the period with active raking and to still 17 % in the recovery period.? Conclusions
These results contribute to the still very limited understanding about the impact of whole-tree harvesting on forest productivity in Germany by laying down an upper limit of possible effects due to nutrient removal, as nutrient loss by litter raking tends to be higher than nutrient loss by whole-tree harvesting. 相似文献19.
Jorge Olivar Stella Bogino Cyrille Rathgeber Vivien Bonnesoeur Felipe Bravo 《Annals of Forest Science》2014,71(3):395-404
? Context
Modification of stand density by thinning may buffer the response of tree growth and vigor to changes in climate by enhancing soil water availability.? Aims
We tested the impact of thinning intensity on cambial growth of Aleppo pine (Pinus halepensis L.) under semi-arid, Mediterranean conditions.? Methods
A multiple thinning experiment was established on an Aleppo pine plantation in Spain. We analysed the stem growth dynamics of two different crown classes under four different thinning intensities (15 %, 30 %, and 45 % removal of the basal area) for 2 years, based on biweekly band dendrometer recordings. Local relative extractable soil water was derived from the use of a water balance model Biljou© (available at https://appgeodb.nancy.inra.fr/biljou/) and used as an explanatory variable.? Results
Radial growth was mainly controlled by soil water availability during the growing season, and differed by crown class. The growth rates of dominant trees were significantly higher than the growth rates of suppressed trees. Removal of 30 % and 45 % of the initial basal area produced a growth release in both dominant and suppressed trees that did not occur under less intense thinning treatments.? Conclusions
Soil water availability was the main driver of radial growth during the growing season. Forest management confirmed its value for ameliorating the effects of water limitations on individual tree growth. These results may help managers understand how altering stand density will differentially affect diameter growth responses of Aleppo pine to short-term climatic fluctuations, promoting forests that are resilient to future climatic conditions. 相似文献20.