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Sean C. Thomas - One of the best experts on this subject based on the ideXlab platform.
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variation in carbon and nitrogen concentration among major Woody tissue types in temperate trees
Canadian Journal of Forest Research, 2015Co-Authors: Adam R. Martin, Sossina Gezahegn, Sean C. ThomasAbstract:Quantifying variation in the Wood Chemical traits of trees is critical for parameterizing forest biogeoChemical budgets and models. Available data on Wood Chemical traits are based largely on samples taken from main stems; few studies have evaluated how Wood Chemical traits vary among major Woody tissue types. We examined variation in Wood carbon (C) and nitrogen (N) concentrations in 17 temperate tree species across five Woody tissue types: sapWood, heartWood, small branches, coarse roots, and bark; analyses were corrected for losses of volatile C. Both C and N varied significantly among tissue types, but differences were driven mainly by high C and N in bark, a pattern observed for nearly all species. Among nonbark tissue types, bivariate correlations among sapWood, heartWood, small branches, and coarse roots were highly significant and positive for Wood C (r = 0.88–0.98) and N (r = 0.66–0.95) concentrations. We suggest that intraspecific variation in C across tissue types is less important than intersp...
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Size-dependent changes in leaf and Wood Chemical traits in two Caribbean rainforest trees
Tree physiology, 2013Co-Authors: Adam R. Martin, Sean C. ThomasAbstract:Tree functional traits and their link to patterns of growth and demography are central to informing trait-based analyses of forest communities, and mechanistic models of forest dynamics. However, few data are available on how functional traits in trees vary through ontogeny, particularly in tropical species; and less is known about how patterns of size-dependent changes in traits may differ across species of contrasting life-history strategies. Here we describe size-dependent variation in seven leaf functional traits and four Wood Chemical traits, in two Dominican rainforest tree species (Dacryodes excelsa Vahl. and Miconia mirabilis (Aubl.) L.O. Williams), ranging from small saplings to the largest canopy trees. With one exception, all traits showed pronounced variation with tree size (diameter at breast height, DBH). Leaf mass per area (LMA), thickness and tissue density increased monotonically with DBH in both species. Leaf area, leaf nitrogen (N) and carbon (C) : nitrogen (N) ratios also varied significantly with DBH; however, these patterns were unimodal, with peak trait values preceding the DBH at reproductive onset in both species. Size-dependent changes in leaf structural traits (LMA and leaf thickness) were generally similar in both species, while traits associated with leaf-level investment in C gain (leaf area, leaf C : N ratio) showed contrasting ontogenetic trends between species. Wood starch concentration varied with DBH in both species, also showing unimodal patterns with peaks preceding size at reproductive onset. Wood C concentration increased linearly with DBH in both species, though significantly only in M. mirabilis. Size-dependent patterns in Wood Chemical traits were similar between both species. Our data demonstrate pronounced variation in functional traits through tree ontogeny, probably due to a combination of environmental factors and shifts in resource allocation. Such ontogenetic variation is comparable in magnitude with interspecific variation, and so should be accounted for in trait-based studies of forest dynamics, structure and function.
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Size-dependent changes in Wood Chemical traits: a comparison of neotropical saplings and large trees
AoB PLANTS, 2013Co-Authors: Adam R. Martin, Sean C. Thomas, Yong ZhaoAbstract:Wood anatomical traits are important correlates of life-history strategies among tree species, yet little is known about Wood Chemical traits. Additionally, size-dependent changes in Wood Chemical traits have been rarely examined,althoughthesechangesmayrepresent animportantaspectoftreeontogeny.Owingtoselectionforpatho- gen resistance and biomechanical stability, we predicted that saplings would show higher lignin (L) and Wood carbon (Cconv), and lower holocellulose (H) concentrations, compared with conspecific large trees. To test these expectations, we quantified H, L and Cconv in co-occurring Panamanian tree species at the large tree vs. sapling size classes. We also examined inter- and intraspecific patterns using multivariate and phylogenetic analyses. In 15 of 16 species, sapling L concentration was higher than that in conspecific large trees, and in all 16 species, sapling H was lower than that in conspecific large trees. In 16 of 24 species, Cconv was higher in saplings than conspecific large trees. All large-tree traits were unrelated to sapling values and were unrelated to four life-history variables. Wood Chemical traits did not show a phylogenetic signal in saplings, instead showing similar values across distantly related taxa; in large trees, only H showed a significant phylogenetic signal. Size-dependent changes in Wood chemistry show consistent and pre- dictable patterns, suggesting that ontogenetic changes in Wood Chemical traits are an important aspect of tree func- tional biology. Our results are consistent with the hypothesis that at early ontogenetic stages, trees are selected for greater L to defend against cellulose-decaying pathogens, or possibly to confer biomechanical stability.
Adam R. Martin - One of the best experts on this subject based on the ideXlab platform.
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variation in carbon and nitrogen concentration among major Woody tissue types in temperate trees
Canadian Journal of Forest Research, 2015Co-Authors: Adam R. Martin, Sossina Gezahegn, Sean C. ThomasAbstract:Quantifying variation in the Wood Chemical traits of trees is critical for parameterizing forest biogeoChemical budgets and models. Available data on Wood Chemical traits are based largely on samples taken from main stems; few studies have evaluated how Wood Chemical traits vary among major Woody tissue types. We examined variation in Wood carbon (C) and nitrogen (N) concentrations in 17 temperate tree species across five Woody tissue types: sapWood, heartWood, small branches, coarse roots, and bark; analyses were corrected for losses of volatile C. Both C and N varied significantly among tissue types, but differences were driven mainly by high C and N in bark, a pattern observed for nearly all species. Among nonbark tissue types, bivariate correlations among sapWood, heartWood, small branches, and coarse roots were highly significant and positive for Wood C (r = 0.88–0.98) and N (r = 0.66–0.95) concentrations. We suggest that intraspecific variation in C across tissue types is less important than intersp...
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Size-dependent changes in leaf and Wood Chemical traits in two Caribbean rainforest trees
Tree physiology, 2013Co-Authors: Adam R. Martin, Sean C. ThomasAbstract:Tree functional traits and their link to patterns of growth and demography are central to informing trait-based analyses of forest communities, and mechanistic models of forest dynamics. However, few data are available on how functional traits in trees vary through ontogeny, particularly in tropical species; and less is known about how patterns of size-dependent changes in traits may differ across species of contrasting life-history strategies. Here we describe size-dependent variation in seven leaf functional traits and four Wood Chemical traits, in two Dominican rainforest tree species (Dacryodes excelsa Vahl. and Miconia mirabilis (Aubl.) L.O. Williams), ranging from small saplings to the largest canopy trees. With one exception, all traits showed pronounced variation with tree size (diameter at breast height, DBH). Leaf mass per area (LMA), thickness and tissue density increased monotonically with DBH in both species. Leaf area, leaf nitrogen (N) and carbon (C) : nitrogen (N) ratios also varied significantly with DBH; however, these patterns were unimodal, with peak trait values preceding the DBH at reproductive onset in both species. Size-dependent changes in leaf structural traits (LMA and leaf thickness) were generally similar in both species, while traits associated with leaf-level investment in C gain (leaf area, leaf C : N ratio) showed contrasting ontogenetic trends between species. Wood starch concentration varied with DBH in both species, also showing unimodal patterns with peaks preceding size at reproductive onset. Wood C concentration increased linearly with DBH in both species, though significantly only in M. mirabilis. Size-dependent patterns in Wood Chemical traits were similar between both species. Our data demonstrate pronounced variation in functional traits through tree ontogeny, probably due to a combination of environmental factors and shifts in resource allocation. Such ontogenetic variation is comparable in magnitude with interspecific variation, and so should be accounted for in trait-based studies of forest dynamics, structure and function.
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Size-dependent changes in Wood Chemical traits: a comparison of neotropical saplings and large trees
AoB PLANTS, 2013Co-Authors: Adam R. Martin, Sean C. Thomas, Yong ZhaoAbstract:Wood anatomical traits are important correlates of life-history strategies among tree species, yet little is known about Wood Chemical traits. Additionally, size-dependent changes in Wood Chemical traits have been rarely examined,althoughthesechangesmayrepresent animportantaspectoftreeontogeny.Owingtoselectionforpatho- gen resistance and biomechanical stability, we predicted that saplings would show higher lignin (L) and Wood carbon (Cconv), and lower holocellulose (H) concentrations, compared with conspecific large trees. To test these expectations, we quantified H, L and Cconv in co-occurring Panamanian tree species at the large tree vs. sapling size classes. We also examined inter- and intraspecific patterns using multivariate and phylogenetic analyses. In 15 of 16 species, sapling L concentration was higher than that in conspecific large trees, and in all 16 species, sapling H was lower than that in conspecific large trees. In 16 of 24 species, Cconv was higher in saplings than conspecific large trees. All large-tree traits were unrelated to sapling values and were unrelated to four life-history variables. Wood Chemical traits did not show a phylogenetic signal in saplings, instead showing similar values across distantly related taxa; in large trees, only H showed a significant phylogenetic signal. Size-dependent changes in Wood chemistry show consistent and pre- dictable patterns, suggesting that ontogenetic changes in Wood Chemical traits are an important aspect of tree func- tional biology. Our results are consistent with the hypothesis that at early ontogenetic stages, trees are selected for greater L to defend against cellulose-decaying pathogens, or possibly to confer biomechanical stability.
Yong Zhao - One of the best experts on this subject based on the ideXlab platform.
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Size-dependent changes in Wood Chemical traits: a comparison of neotropical saplings and large trees
AoB PLANTS, 2013Co-Authors: Adam R. Martin, Sean C. Thomas, Yong ZhaoAbstract:Wood anatomical traits are important correlates of life-history strategies among tree species, yet little is known about Wood Chemical traits. Additionally, size-dependent changes in Wood Chemical traits have been rarely examined,althoughthesechangesmayrepresent animportantaspectoftreeontogeny.Owingtoselectionforpatho- gen resistance and biomechanical stability, we predicted that saplings would show higher lignin (L) and Wood carbon (Cconv), and lower holocellulose (H) concentrations, compared with conspecific large trees. To test these expectations, we quantified H, L and Cconv in co-occurring Panamanian tree species at the large tree vs. sapling size classes. We also examined inter- and intraspecific patterns using multivariate and phylogenetic analyses. In 15 of 16 species, sapling L concentration was higher than that in conspecific large trees, and in all 16 species, sapling H was lower than that in conspecific large trees. In 16 of 24 species, Cconv was higher in saplings than conspecific large trees. All large-tree traits were unrelated to sapling values and were unrelated to four life-history variables. Wood Chemical traits did not show a phylogenetic signal in saplings, instead showing similar values across distantly related taxa; in large trees, only H showed a significant phylogenetic signal. Size-dependent changes in Wood chemistry show consistent and pre- dictable patterns, suggesting that ontogenetic changes in Wood Chemical traits are an important aspect of tree func- tional biology. Our results are consistent with the hypothesis that at early ontogenetic stages, trees are selected for greater L to defend against cellulose-decaying pathogens, or possibly to confer biomechanical stability.
Masaru Shibata - One of the best experts on this subject based on the ideXlab platform.
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Quantitative FT-Raman spectroscopy to measure Wood cell dimensions
The Analyst, 1999Co-Authors: Toshihiro Ona, Tetsuya Sonoda, Masaru Shibata, Kazuya Ito, Y. Ootake, Jyunichi Ohshima, Shinso Yokota, Nobuo YoshizawaAbstract:Vibrational spectroscopy is utilized to determine compounds. However, it has never been applied to quantify architecture of multicell biological specimens. By using Fourier transform Raman spectroscopy coupled with multivariate data analysis and Wood meal samples of Eucalyptus camaldulensis and E. globulus trees, cell width and cell wall thickness of vessels and fibers, which mainly constitute hardWood xylem, were successfully quantified with correlation coefficients >0.8, both in the calibration and in the prediction against microscopically measured values for all traits. The important frequencies were found to contain Wood Chemical and physical information.
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Relations between various extracted basic densities and Wood Chemical components in Eucalyptus globulus
Journal of Wood Science, 1998Co-Authors: Tetsuya Sonoda, Masaru ShibataAbstract:Relations between various extracted basic densities and Wood Chemical components were investigated by their within-tree variations in Eucalyptus globulus for assistance in the prediction of the properties of Wood or Wood-derived products. Extraneous compounds affect the relations between various basic densities and Wood Chemical components such as holocellulose and the lignin syringyl/guaiacyl ratio. We also discuss the relation of various densities, the molar composition of neutral sugars constituting hemicellulose, and fiber morphology.
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Relationship between various extracted basic densities and Wood Chemical components in Eucalyptus camaldulensis
Wood Science and Technology, 1997Co-Authors: Toshihiro Ona, Tetsuya Sonoda, Kazuya Ito, Masaru ShibataAbstract:Relationship between various extracted basic densities and Wood Chemical components were investigated by their within-tree variations inEucalyptus camaldulensis for assistance in the prediction of the properties of Wood or Wood derived products. Within-tree variation was not observed for basic density because extraneous compounds masked it. However, extractives-free basic density, total extractives-free basic density and extraneous compounds-free basic density were high on the bark side and top parts in the trunk. These extracted basic densities were expected to have significant relationships to the fiber morphology causing the within-tree variations, and to be very important factors for Wood industries. These relationships were sought by correlations between extracted basic densities and Wood Chemical components based on their within-tree variations. Furthermore, fair relationships between extracted basic densities and hemicellulose composition were observed and speculation made as to the relationship to the constituent ratio of cell wall layers.
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Use of the radially divided increment core method to assess pulpWood quality for eucalypt breeding in E. camaldulensis and E. globulus
Appita Journal, 1996Co-Authors: Toshihiro Ona, Tetsuya Sonoda, Masaru Shibata, Kazuya Ito, Yutaka Tamai, Yasuo KojimoAbstract:Whole-tree pulp properties were predicted by regression equations using weighted averages of Wood properties at given heights below 3.3 m above ground. The most appropriate height was examined for the core sampling to assess pulpWood quality of Eucalyptus camaldulensis and E. globulus (age 14 years). Pulp properties considered were yield, sheet density, burst factor, breaking length, tear factor, folding endurance, unbleached brightness, and Kappa number and for Wood properties, basic density, extracted basic density, Wood Chemical composition, extractives-free Wood Chemical composition, lignin syringyl:guaiacyl ratio, and neutral sugar mol% constituting hemicellulose were utilized. The most appropriate heights were 2.3-2.8 m above ground for E. camaldulensis, and 2.8 m for E. globulus against all pulp properties, and 2.8 m for both species against pulpWood productivity, and were concluded to be 2.8 m overall for both species. As a result, the whole-tree pulp properties and pulpWood productivity could be estimated using one increment core with Chemical analysis of Wood properties only.
Philippe Gerardin - One of the best experts on this subject based on the ideXlab platform.
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Effect of heat treatment intensity on Wood Chemical composition and decay durability of Pinus patula.
European Journal of Wood and Wood Products, 2011Co-Authors: Ahmed Mohareb, Mathieu Petrissans, Peter Sirmah, Philippe GerardinAbstract:Heat treatment is an effective method to improve biological resistance of low natural durability Wood species. The aim of this study was to enhance the decay resistance of Pinus patula, an African low natural durability softWood species, via Wood thermal modification technique. Heat treatment was performed on Wood specimens under inert conditions at different heat treatment intensities to reach mass losses of 5, 10 and 15%. Heat treated specimens were exposed to fungal decay using the brown rot fungus Poria placenta. The Wood Chemical and elemental composition was determined as well as extractives toxicity before and after Wood thermal modification to understand the reasons of durability improvement. The treated specimens exhibited a significant increase in their durability against Wood decay in line with the severity of the treatment. Wood holocellulose was found to be distinctly more sensitive to the heating process than the lignin constituent. In addition, obvious correlations were observed between weight losses recorded after fungal exposure and both holocellulose decrease and lignin ratio increase. The same correlations were observed with the elemental composition changes allowing using the observed differences for predicting of Wood durability conferred by heat treatment. Furthermore, no significant differences were observed between the toxicity of Pinus patula Wood extractives before and after its thermal modification.
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evaluation of thermally modified grevillea robusta heartWood as an alternative to shortage of Wood resource in kenya characterisation of physicoChemical properties and improvement of bio resistance
Bioresource Technology, 2007Co-Authors: Francis Mburu, Stephane Dumarcay, Francoise Huber, Mathieu Petrissans, Philippe GerardinAbstract:Abstract Heat treatment of Grevillea robusta , a tropical Wood species of low natural durability, was carried-out under inert conditions to improve its decay resistance. Resistance of heat treated samples was evaluated by malt agar block tests after three months of exposure to several Wood rotting fungi. Also resistance of heat treated Wood against termites was tested in the laboratory and in the field. Results showed that durability against fungi and termites was greatly improved after treatment. There was a good correlation between decay resistance and mass loss due to thermal treatment. Microscopic, FTIR and 13 C MAS NMR analysis were performed to characterize Wood Chemical and anatomical modifications that occur after treatment to understand the reasons of the durability improvement.
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xps characterization of Wood Chemical composition after heat treatment
Surface and Interface Analysis, 2006Co-Authors: Nguila G Inari, Mathieu Petrissans, Jacques Lambert, Jean-jacques Ehrhardt, Philippe GerardinAbstract:XPS was used to characterize the Chemical changes occurring after drying or applying a heat-treatment to beech Wood samples. Our results indicate that the surface of this air-exposed material could be strongly affected either by the ambient atmosphere during storage or by the complex atmosphere in the oven during drying or heat-treatment. However, the O/C ratio measured after removal of a thin slice of a few millimetres of an untreated sample is in reasonable agreement with that calculated from the wellestablished Chemical composition of beech. Through this methodology (equivalent to scraping for hard materials) it is expected to get a realistic characterization of the Wood. The reliability and repeatability of the XPS measurements have been checked and the method applied to the study of the Chemical changes of the beech samples subjected to heat-treatment. Heating at 240 °C induces a significant decrease of the O/C ratio from 0.55 before to 0.44 after the treatment. Heat-treatment induces also a decrease of the C2 carbon contribution (carbon atom bound to a single non-carbonyl oxygen) associated with an increase of the C1 carbon contribution (carbon atoms bound only to carbon or hydrogen atoms), in agreement with Chemical modifications reported previously in the literature. Thanks to the small analysed area of the equipment used in this study, different spots were analysed to demonstrate the presence or absence of a gradient of Chemical composition due to thermal degradation or migration of extractives from within the Wood structure to its surface. At the scale of our observations, the different Wood samples investigated (dried or heat treated) appear to be homogeneous. Copyright 2006 John Wiley & Sons, Ltd.
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XPS characterization of Wood Chemical composition after heat‐treatment
Surface and Interface Analysis, 2006Co-Authors: G. Nguila Inari, Mathieu Petrissans, Jacques Lambert, Jean-jacques Ehrhardt, Philippe GerardinAbstract:XPS was used to characterize the Chemical changes occurring after drying or applying a heat-treatment to beech Wood samples. Our results indicate that the surface of this air-exposed material could be strongly affected either by the ambient atmosphere during storage or by the complex atmosphere in the oven during drying or heat-treatment. However, the O/C ratio measured after removal of a thin slice of a few millimetres of an untreated sample is in reasonable agreement with that calculated from the wellestablished Chemical composition of beech. Through this methodology (equivalent to scraping for hard materials) it is expected to get a realistic characterization of the Wood. The reliability and repeatability of the XPS measurements have been checked and the method applied to the study of the Chemical changes of the beech samples subjected to heat-treatment. Heating at 240 °C induces a significant decrease of the O/C ratio from 0.55 before to 0.44 after the treatment. Heat-treatment induces also a decrease of the C2 carbon contribution (carbon atom bound to a single non-carbonyl oxygen) associated with an increase of the C1 carbon contribution (carbon atoms bound only to carbon or hydrogen atoms), in agreement with Chemical modifications reported previously in the literature. Thanks to the small analysed area of the equipment used in this study, different spots were analysed to demonstrate the presence or absence of a gradient of Chemical composition due to thermal degradation or migration of extractives from within the Wood structure to its surface. At the scale of our observations, the different Wood samples investigated (dried or heat treated) appear to be homogeneous. Copyright 2006 John Wiley & Sons, Ltd.
