A5019672593- Forest ecology and management
- Plant Water Relations and Carbon Dynamics
- Plant responses to elevated CO2
- Nuts composition and effects
- Soil Carbon and Nitrogen Dynamics
- Botany and Plant Ecology Studies
- Plant Physiology and Cultivation Studies
- Horticultural and Viticultural Research
- Tree-ring climate responses
- Tree Root and Stability Studies
- African Botany and Ecology Studies
- Forest Biomass Utilization and Management
- Agriculture and Rural Development Research
- Seedling growth and survival studies
- Leaf Properties and Growth Measurement
- Crop Yield and Soil Fertility
- Plant nutrient uptake and metabolism
- Ecology and Vegetation Dynamics Studies
- Forest Insect Ecology and Management
- Forest Ecology and Biodiversity Studies
- Agriculture, Plant Science, Crop Management
- Fern and Epiphyte Biology
- Bioenergy crop production and management
- Photosynthetic Processes and Mechanisms
- Peatlands and Wetlands Ecology
Université de Lorraine
2010-2024
AgroParisTech
2019-2024
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
1990-2024
University of French Guiana
2023
Physique et Physiologie Intégratives de l'Arbre en Environnement Fluctuant
1992-2023
Université des Antilles
2023
Interactions Arbres-Microorganismes
2022
Silva
2018-2020
Centre National de la Propriété Forestière
2019
Ecologie et Ecophysiologie Forestières
2008-2017
Non-structural carbohydrates (NSC) in plant tissue are frequently quantified to make inferences about responses environmental conditions. Laboratories publishing estimates of NSC woody plants use many different methods evaluate NSC. We asked whether the recent literature could be quantitatively compared among studies. also any differences laboratories were related extraction and quantification used determine starch sugar concentrations. These questions addressed by sending sub-samples...
The study of the fate assimilated carbon in respiratory fluxes field is needed to resolve residence and transfer times atmosphere–plant–soil system forest ecosystems, but it requires high frequency measurements isotopic composition evolved CO2. We developed a closed transparent chamber label whole crown tree labelling capable delivering 3-h pulse 99% 13CO2 field. compositions trunk soil CO2 effluxes were recorded continuously on two labelled one control trees by tuneable diode laser...
• Phloem is the main pathway for transferring photosynthates belowground. In situ13C pulse labelling of trees 8–10 m tall was conducted in field on 10 beech (Fagus sylvatica) trees, six sessile oak (Quercus petraea) and maritime pine (Pinus pinaster) throughout growing season. Respired 13CO2 from trunks tracked at different heights using tunable diode laser absorption spectrometry to determine time lags velocity carbon transfer (V). The isotope composition phloem extracts measured several...
Knowledge of the physiological mechanisms underlying species vulnerability to drought is critical for better understanding patterns tree mortality. Investigating plant adaptive strategies should thus help fill this knowledge gap, especially in tropical rainforests exhibiting high functional diversity. In a semi-controlled experiment using 12 rainforest species, we investigated diversity hydraulic and whether they determined ability saplings use stored non-structural carbohydrates during an...
We assessed the pools of non-structural nitrogen compounds (NSNC) through a year, thereby addressing question whether mature sessile oak [Quercus petraea (Matt.)Liebl.] and beech (Fagus sylvatica L.), which differ in wood anatomy growth patterns, exhibit contrasting seasonal dynamics NSNC as previously shown for carbohydrate (NSC) pools.Seasonal fluctuations (amino acids soluble proteins) NSC (starch sugars) were analyzed inner outer stem sapwood.In oak, showed marked variation within...
13 CO2 pulse-labelling experiments were performed in situ on adult beeches (Fagus sylvatica) and pines (Pinus pinaster) at different phenological stages to study seasonal interspecific short-term dynamics partitioning of recently assimilated carbon (C) leaves. Polar fraction (PF, including soluble sugars, amino acids organic acids) starch purified from foliage sampled during a 10-d chase period. C contents, isotopic compositions parameters determined bulk foliage, PF starch. Decrease amount...
Background and Aims The carbon (C) nitrogen (N) needed for plant growth can come either from soil N current photosynthesis or through remobilization of stored resources. contribution to new organ on a whole-plant basis is quite well known in deciduous woody plants evergreen conifers, but this information very limited broadleaf trees. This study compares the remobilized C construction organs spring, assesses importance different as sources 1-year-old potted seedlings four ecologically...
Trees will have to cope with increasing levels of CO2 and ozone in the atmosphere. The purpose this work was assess whether lignification process could be altered wood poplars under elevated and/or ozone. Young were exposed either charcoal-filtered air (control), (800 μl l−1), (200 nl l−1) or a combination controlled chambers. Lignification analysed at different levels: biosynthesis pathway activities (enzyme transcript), lignin content, capacity incorporate new assimilates by using 13C...
We used long-term in situ 15N labeling of the soil to investigate contribution two main nitrogen (N) sources (N uptake versus N reserves) sun shoot growth from bud burst full leaf expansion 50-year-old sessile oaks. Recovery by growing compartments (leaves, twigs and buds) presence phloem sap were checked weekly. During first 2 weeks following burst, remobilized contributed ∼90% total leaves twigs. Nitrogen started concomitantly with remobilization but only slightly burst. However, fraction...
Soil nitrogen can alter storage and remobilization of carbon in forest trees affect growth responses to elevated dioxide concentration ([CO(2)]). We investigated these effects oak saplings (Quercus robur L.) exposed for two years ambient or twice [CO(2)] combination with low- (LN, 0.6 mmol N l(-1)) high-nitrogen (HN, 6.1 fertilization. Autumn retranslocation efficiency from senescing leaves was less HN than LN saplings, but about 15% sapling lost the litter. During dormant season,...
The distribution of carbon (C) into whole grapevine fruiting cuttings was investigated during flower development to determine the relative contribution inflorescence and leaf photoassimilates in total C balance investigate their partitioning towards other plant organs. A 13C labelling procedure used label by leaves inflorescences grapevine. Investigations were carried out at various stages flower/berry development, from separated cluster fruit set, using with four (Vitis vinifera L. cv....
ABSTRACT Non‐structural carbohydrates (NSC) are considered as indicators of the balance between tree carbon sources and sinks reflect functional strategies throughout different biomes. However, little is known about contribution NSC to economics, in particular, whether leaf, stem coarse root traits co‐ordinate together into a whole‐tree economics spectrum. Twenty‐four (including content) were measured leaves, xylem up 90 angiosperm species temperate, Mediterranean tropical climates. By...
Forest trees adopt effective strategies to optimize nitrogen (N) use through internal N recycling. In the context of more recurrent environmental stresses due climate change, question remains whether increased frequency drought or defoliation threatens this recycling strategy. We submitted 8-year-old beech 2 years either severe (Dro) manual (Def) create a state starvation. At end second year before leaf senescence, we labeled foliage Dro and Def trees, as well that control (Co) with...
Wood performs several functions to ensure tree survival and carbon allocation a finite stem volume leads trade-offs among cell types. It is not known what extent these modify functional if they are consistent across climates evolutionary lineages. Twelve wood traits were measured in stems coarse roots 60 adult angiosperm species from temperate, Mediterranean tropical climates. Regardless of climate, clear occurred cellular fractions, but did translate into specific trade-offs. density was...
Changes in use of both stored and newly synthesized sources carbon (C) nitrogen (N) were investigated during rooting leafy cuttings Larix x eurolepis A. Henry. We used dual (13)C (15)N long-term labeling reserves stock plants followed isotope dilution the labels to determine respective proportions C N derived from plant (Q(C,old), Q(N,old)) (Q(C,new), Q(N,new)). also assessed their partitioning into growing needles roots. Because development occurred over several months, destructive harvests...
Pedunculate oak (Quercus robur L.) seedlings were grown for 3 or 4 months (second- and third-flush stages) in greenhouses at two atmospheric CO2 concentrations ([CO2]) (350 700 micromol mol(-1)) nitrogen fertilization regimes (6.1 0.61 mmol N l(-1) nutrient solution). Combined effects of [CO2] on partitioning newly acquired carbon (C) (N) assessed by dual 13C 15N short-term labeling the second- stage development. In low-N treatment, root growth, but not shoot was stimulated elevated [CO2],...
Abstract Estimating symbiotic di‐nitrogen (N 2 ) fixation is challenging, especially when working with woody N fixers in field trials. Fortunately, isotope methods based on 15 natural abundance or artificial enrichment (dilution method) make it possible to estimate the proportion of nitrogen derived from atmosphere (Ndfa) ‐fixing species. These have been extensively used for herbaceous species, much less tree species such as alder and acacia, rarely black locust ( Robinia pseudoacacia ). The...