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| Author | Alméras, T.; Ghislain, B.; Clair, B.; Secerovic, A.; Pilate, G.; Fournier, M. | ||||
| Title | Quantifying the motor power of trees | Type | Journal Article | ||
| Year | 2018 | Publication  |
Trees | Abbreviated Journal | |
| Volume | 32 | Issue | 3 | Pages | 689-702 |
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| Abstract | Wood maturation strains can be estimated from the change in curvature that occurs when a stem grown staked in tilted position is released from the stake.
Trees have a motor system to enable upright growth in the field of gravity. This motor function is taken on by reaction wood, a special kind of wood that typically develops in leaning axes and generates mechanical force during its formation, curving up the stem and counteracting the effect of gravity or other mechanical disturbances. Quantifying the mechanical stress induced in wood during maturation is essential to many areas of research ranging from tree architecture to functional genomics. Here, we present a new method for quantifying wood maturation stress. It consists of tilting a tree, tying it to a stake, letting it grow in tilted position, and recording the change in stem curvature that occurs when the stem is released from the stake. A mechanical model is developed to make explicit the link between the change in curvature, maturation strain and morphological traits of the stem section. A parametric study is conducted to analyse how different parameters influence the change in curvature. This method is applied to the estimation of maturation strain in two different datasets. Results show that the method is able to detect genotypic variations in motor power expression. As predicted by the model, we observe that the change in stem curvature is correlated to stem diameter and diameter growth. In contrast, wood maturation strain is independent from these dimensional effects, and is suitable as an intrinsic parameter characterising the magnitude of the plant’s gravitropic reaction. |
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| ISSN | 1432-2285 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ Alméras2018 | Serial | 835 | ||
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| Author | Bossu, J.; Lehnebach, R.; Corn, S.; Regazzi, A.; Beauchene, J.; Clair, B. | ||||
| Title | Interlocked grain and density patterns in Bagassa guianensis: changes with ontogeny and mechanical consequences for trees | Type | Journal Article | ||
| Year | 2018 | Publication |
Trees | Abbreviated Journal | |
| Volume | 32 | Issue | 6 | Pages | 1643-1655 |
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| Abstract | Interlocked grain and basic density increase from pith to bark in Bagassa guianensis and greatly improve trunk torsional stiffness and wood tenacity in the radial plane. | ||||
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| ISSN | 1432-2285 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ Bossu2018 | Serial | 852 | ||
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| Author | Gonzalès-Melo, Andrès ; Posada, Juan Manuel ; Beauchêne, Jacques ; Lehnebach, Romain ; Leviennois, Sébastien ; Rivera, Katherine ; Clair, Bruno | ||||
| Title | Radial variations in wood functional traits in a rain forest from eastern Amazonia | Type | Journal Article | ||
| Year | 2021 | Publication |
Trees | Abbreviated Journal | |
| Volume | 36 | Issue | Pages | 569–581 | |
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| Abstract | Trees can modify their wood structure in response to changes in mechanical, hydraulic and storage demands during their life-cycles. Thus, examining radial variations in wood traits is important to expand our knowledge of tree functioning and species ecological strategies. Yet, several aspects of radial changes in wood functional traits are still poorly understood, especially in angiosperm trees from tropical humid forests. Here, we examined radial shifts in wood traits in trunks of tropical forest species and explored their potential ecological implications. We first examined radial variations in wood specific gravity (WSG). Then, we asked what anatomical traits drove radial variations in WSG, and whether WSG, vessel fraction and specific hydraulic conductivity vary independently from each other along the radius gradients. We measured WSG and eight wood anatomical traits, at different radial positions along the trunks, in 19 tree species with contrasting shade-tolerance from a lowland tropical forest in eastern Amazonia. Most species had significant radials shifts in WSG. Positive radial gradients in WSG (i.e., increments from pith to bark) were common among shade-intolerant species and were explained by different combinations of fiber and parenchyma traits, while negative radial shifts in WSG (e.g., decreases towards the bark) were present in shade-tolerants, but were generally weakly related to anatomical traits. We also found that, in general, WSG was unrelated to vessel fraction and specific hydraulic conductivity in any radial position. This study illustrates the contrasting radial variations in wood functional traits that occur in tree species from a humid lowland tropical forest. In particular, our results provide valuable insights into the anatomical traits driving WSG variations during tree development. These insights are important to expand our knowledge on tree ecological strategies by providing evidence on how wood allocation varies as trees grow, which in turn can be useful in studying trait-demography associations, and in estimating tree above-ground biomass. | ||||
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| Publisher | Springer Link | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1037 | ||
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| Author | Bompy, F.; Imbert, D.; Dulormne, M. | ||||
| Title | Impact patterns of soil salinity variations on the survival rate, growth performances, and physiology of Pterocarpus officinalis seedlings | Type | Journal Article | ||
| Year | 2015 | Publication |
Trees – Structure and Function | Abbreviated Journal | Trees – Structure and Function |
| Volume | 29 | Issue | 1 | Pages | 119-128 |
| Keywords | Acclimation; Leaf chemical composition; Leaf gas exchange; NaCl salinity; Tropical swamp forest; Vegetative growth | ||||
| Abstract | Key message: Pterocarpus officinalisis able to (1) improve its acclimation capacity if soil salinity increases slowly and (2) benefit from afreshwater episode.
Abstract: One likely effect of global change is an increase of the amplitude of salt variations in the soil of brackish coastal wetland forests. In the Antilles, such forests are dominated by the species Pterocarpus officinalis. The study aimed to determine the effect of 3 salinity levels (freshwater, moderate, and hypersalinity—i.e., 0, 10, and 30 ‰, respectively) and 3 patterns of salinity variation (fast or slow salinity increase, fluctuating salinity) on the growth and ecophysiology of P. officinalis seedlings. P. officinalis proved tolerant to 10 ‰ salinity, even if at this salt concentration the water constraint altered the plant’s water status and reduced stomatal conductance. No impact of the pattern of salinity variation was observed at 10 ‰. Seedlings were strongly affected by hypersalinity, but were able to acclimatize efficiently and to improve their performances (higher survival, total biomass, and photosynthesis) when salinity increased slowly. Young P. officinalis were also able to take advantage of a freshwater episode on the longer term, certainly through leaf desalination associated with enhanced photosynthesis and water use efficiency. Higher soil salinity and more intense dry seasons in the context of climate change could affect the stand-level regeneration potential of P. officinalis seedlings. © 2014, Springer-Verlag Berlin Heidelberg. |
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| Address | UMR ECOFOG-DYNECAR, UFR des Sciences Exactes et Naturelles, Université des Antilles et de la Guyane, Pointe-à-PitreGuadeloupe (F.W.I.), France | ||||
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| Notes | Export Date: 9 April 2015 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 595 | ||
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| Author | Morel, H.; Mangenet, T.; Beauchene, J.; Ruelle, J.; Nicolini, E.; Heuret, P.; Thibaut, B. | ||||
| Title | Seasonal variations in phenological traits: leaf shedding and cambial activity in Parkia nitida Miq. and Parkia velutina Benoist (Fabaceae) in tropical rainforest | Type | Journal Article | ||
| Year | 2015 | Publication |
Trees – Structure and Function | Abbreviated Journal | Trees – Structure and Function |
| Volume | 29 | Issue | 4 | Pages | 973-984 |
| Keywords | Cambial activity; Climate; French Guiana; Leaf shedding pattern; Tropical rainforest | ||||
| Abstract | Key message: In French Guiana, the leaf and cambium phenologies should not be considered only as exogenous-driven processes, as the dry season, but also as endogenous-driven, as tree development stage. Abstract: Studies of the periodicity of wood formation provide essential data on tree age and on factors that control tree growth. The aim of this work was to investigate cambial phenology and its relation with leaf phenology and climatic seasonality in two briefly deciduous tropical rainforest species belonging to the genus Parkia. Wood microcores were collected every 15 days from April 2009 to February 2012 from five trees of each species. The microcores were stained with cresyl violet acetate to facilitate counting the number of cells in the cambial zone, in the radial enlargement zone and wall-thickening zone. At the same time, we observed leaf shedding pattern in the crown of the same trees. In both species, cambial activity was significantly reduced during the leafless period. In P. nitida, these two concomitant events were observed during the dry season whereas in P. velutina they can occur anytime in the year with no apparent link with seasonality. In conclusion, the period of reduced cambial activity in some tropical rainforest trees may be independent of rainfall seasonality and not necessarily follow an annual cycle. It appears that leaf phenology is a good proxy to estimate cambial activity. © 2015, Springer-Verlag Berlin Heidelberg. | ||||
| Address | CNRS, UMR Laboratoire de Mécanique et Génie Civil de Montpellier, Montpellier, France | ||||
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| Notes | Export Date: 16 July 2015 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 610 | ||
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| Author | Hein, P.R.G.; Chaix, G.; Clair, B.; Brancheriau, L.; Gril, J. | ||||
| Title | Spatial variation of wood density, stiffness and microfibril angle along Eucalyptus trunks grown under contrasting growth conditions | Type | Journal Article | ||
| Year | 2016 | Publication |
Trees – Structure and Function | Abbreviated Journal | |
| Volume | 30 | Issue | 3 | Pages | 871-882 |
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| Abstract | Sloped terrains tend to produce trees with higher radial variation in wood density while at high wind speeds, the wood tends to present higher stiffness and lower MFA in Eucalyptus. | ||||
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| ISSN | 1432-2285 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ Hein2016 | Serial | 720 | ||
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| Author | Lehnebach, R.; Morel, H.; Bossu, J.; Le Moguédec, G.; Amusant, N.; Beauchene, J.; Nicolini, E. | ||||
| Title | Heartwood/sapwood profile and the tradeoff between trunk and crown increment in a natural forest: the case study of a tropical tree (Dicorynia guianensis Amsh., Fabaceae) | Type | Journal Article | ||
| Year | 2017 | Publication |
Trees – Structure and Function | Abbreviated Journal | Trees – Structure and Function |
| Volume | 31 | Issue | 1 | Pages | 199-214 |
| Keywords | Dicorynia guianensis; Growth allocation; Heartwood; Ontogeny; Sapwood; Tropical tree | ||||
| Abstract | Key message: Sapwood area and the radial growth rate of the trunk follow the same pattern at breast height, with an initial increase and subsequent constant value, resulting from the increasing growth allocation toward the crown rather than tree decline. Heartwood area and heartwood volume in the trunk increase more rapidly after this shift occurs. Abstract: Sapwood (SW) and heartwood (HW) are two functionally distinct classifications of wood in perennial stems for which quantities can vary greatly in tropical trees. Numerous positive correlations have been found between the radial growth rate (RGR) and SW quantity; however, variations in the SW/HW quantities have not been studied in light of the ontogenetic variation of RGR. Wood core sampling, intensive measurements of tree structure (number of branches, stem volumes), and radial growth monitoring were performed on an abundant and highly exploited tree species in French Guiana (Dicorynia guianensis) to investigate the relationship between RGR, SW/HW quantity, tree structure, and their variations on the course of a tree’s ontogeny. SW area and RGR followed the same pattern of variation throughout tree development, both increasing first and reaching a steady state after 50 cm DBH (diameter at breast height). After this value, we observed a strong increase in both the HW area and HW volume increment, concomitant with a more rapid increase in crown volume. The stabilization of RGR for trees with DBH > 50 cm was related not to a tree’s decline but rather to an increasing wood allocation to the crown, confirming that RGR at breast height is a poor indicator of whole-tree growth for bigger individuals. We also confirmed that HW formation is an ontogenetic process managing SW quantity that is continuously and increasingly produced within the crown as the tree grows. This study highlights the effect of growth-mediated ontogenetic changes on the localization of water and carbohydrate storage within a tree, resulting from SW and HW dynamics throughout tree ontogeny. © 2016, Springer-Verlag Berlin Heidelberg. | ||||
| Address | CIRAD, UMR EcoFoG, BP701, Kourou Cedex, French Guiana | ||||
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| Notes | Export Date: 19 February 2017 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 733 | ||
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| Author | Christensen-Dalsgaard, K.K.; Ennos, A.R.; Fournier, M. | ||||
| Title | Are radial changes in vascular anatomy mechanically induced or an ageing process? Evidence from observations on buttressed tree root systems | Type | Journal Article | ||
| Year | 2008 | Publication |
Trees-Structure and Function | Abbreviated Journal | Trees-Struct. Funct. |
| Volume | 22 | Issue | 4 | Pages | 543-550 |
| Keywords | wood; anatomy; mechanical loading; tree development; vessels | ||||
| Abstract | To investigate the effect of changes in mechanical loading conditions on radial anatomical patterns, we here compare the trunk with the roots in two locations of three species of buttressed trees. The proximal part of the buttress roots is highly mechanically loaded throughout juvenile growth whereas the distal part of the buttresses is though to be mechanically unimportant at formation but become progressively more mechanically loaded during growth. We measured the frequency and diameter of the vessels and the vessel area fraction, and from this calculated the specific conductivity of tissue samples of the core-, intermediate- and outer wood. As in previous studies there was an increase in vessel size, vessel area fraction and specific conductivity from the pith to the bark in the trunk. In the proximal part of the buttress roots, however, there was no increase in vessel size and conductivity from core wood and out in agreement with the high mechanical loading found here throughout growth. There was instead a decrease in vessel size, vessel area fraction and specific conductivity from core- to outer wood in the distal part of the buttress roots in accordance with the increase in mechanical loading. Hence, it appears that the radial anatomical patterns are not a passive function of cambial ageing but may be modified in response to local mechanical loading. | ||||
| Address | [Christensen-Dalsgaard, Karen K.] Univ Alberta, Edmonton, AB T6G 2E3, Canada, Email: kkchrist@ualberta.ca | ||||
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| ISSN | 0931-1890 | ISBN | Medium | ||
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| Notes | ISI:000257385200014 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 136 | ||
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| Author | Ruelle, J.; Yoshida, M.; Clair, B.; Thibaut, B. | ||||
| Title | Peculiar tension wood structure in Laetia procera (Poepp.) Eichl. (Flacourtiaceae) | Type | Journal Article | ||
| Year | 2007 | Publication |
Trees-Structure and Function | Abbreviated Journal | Trees-Struct. Funct. |
| Volume | 21 | Issue | 3 | Pages | 345-355 |
| Keywords | tension wood; tropical rainforest species; UV microspectrophotometry; scanning electron microscopy; cellulose microfibril angle | ||||
| Abstract | Tension wood of Laetia procera (Poepp.) Eichl. (Flacourtiaceae), a neo-tropical forest species, shows a peculiar secondary wall structure, with an alternance of thick and thin layers, while opposite wood of this species has a typical secondary wall structure (S1 + S2 + S3). Samples for the study of microstructural properties were collected upon the estimation of growth stresses in the living tree, in order to analyze the correlation of the former with the latter. Investigation using optical microscopy, scanning electron microscopy and UV microspectrophotometry allowed the description of the anatomy, ultra-structure and chemistry of this peculiar polylaminate secondary wall. In the thick layers, cellulose microfibril angle is very low (i.e., microfibril orientation is close to fibre axis) and cellulose microfibrils are well organized and parallel to each other. In the thin layers, microfibrils (only observable in the inner layer) are less organized and are oriented with a large angle relative to the axis of the cell. Thick layers are lightly lignified although thin layers show a higher content of lignin, close to that of opposite wood secondary wall. The more the wood was under tensile stress, the less the secondary wall was lignified, and lower the syringyl on guaiacyl lignin units' ratio was. The innermost layer of the secondary wall looks like a typical S3 layer with large microfibril angle and lignin occurrence. The interest of this kind of structure for the understanding of stress generation is discussed. | ||||
| Address | UMR EcoFoG, Kourou 97387, French Guiana, Email: ruelle_j@kourou.cirad.fr | ||||
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| ISSN | 0931-1890 | ISBN | Medium | ||
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| Notes | ISI:000246206200009 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 163 | ||
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| Author | Leroy, C.; Gueroult, M.; Wahyuni, N.S.; Escoute, J.; Cereghino, R.; Sabatier, S.; Auclair, D. | ||||
| Title | Morphogenetic trends in the morphological, optical and biochemical features of phyllodes in Acacia mangium Willd (Mimosaceae) | Type | Journal Article | ||
| Year | 2009 | Publication |
Trees-Structure and Function | Abbreviated Journal | Trees-Struct. Funct. |
| Volume | 23 | Issue | 1 | Pages | 37-49 |
| Keywords | Chlorophyll; Phyllode morphology; Phyllode anatomy; Nitrogen; Optical properties; Plant architecture | ||||
| Abstract | Endogenous variations in the annual growth of trees suggest that similar trends would occur in phyllodes. In comparison to leaves, the characteristics of phyllodes are less well known, hence this study examines the effects of architectural position and age of tree on the phyllodes of Acacia mangium. Phyllodes were investigated on 1-, 2-, and 3-year-old trees from three axis positions within the crown. We focused on the morphological, optical and biochemical traits of the phyllodes. The increase in phyllode area and lamina thickness is more pronounced in the older trees. Leaf mass area (LMA), stomatal density, nitrogen and chlorophyll content increase with tree age. The values of these characteristics decrease from the main stem to the lower branches for the older trees. Phyllode light absorptance increased with tree age whereas reflectance was higher for the upper position compared to the lower position within the crown. Carotenoid content and chlorophyll a/b ratio were higher for the younger phyllodes of younger trees. Increasing tree size induced modifications in the phyllode characteristics which are influenced by both morphogenetic and light gradients within the crown. This study demonstrated pronounced changes in terms of morphological and functional indicators of photosynthetic capacity in relation to phyllode position within the crown and to tree age. These morphogenetic effects on the phyllode characteristics should be taken into account in studies on phenotypic plasticity. | ||||
| Address | [Sabatier, Sylvie] CIRAD, UMR AMAP BotAnique & BioinforMat Architecture, F-34398 Montpellier 5, France, Email: sylvie-annabel.sabatier@cirad.fr | ||||
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| ISSN | 0931-1890 | ISBN | Medium | ||
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| Notes | ISI:000262538700005 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 206 | ||
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