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218 results on '"Denis Loustau"'

101. Interception loss, throughfall and stemflow in a maritime pine stand. II. An application of Gash's analytical model of interception

Author: André Granier, Denis Loustau, and Paul Berbigier
Subjects: Canopy, Hydrology, Stemflow, Evaporation rate, Plant cover, Environmental science, Storm, Leaf area index, Interception, Throughfall, Water Science and Technology
Abstract: Interception, throughfall and stemflow were determined in an 18-year-old maritime pine stand for a period of 30 months. This involved 71 rainfall events, each corresponding either to a single storm or to several storms. Gash's analytical model of interception was used to estimate the sensitivity of interception to canopy structure and climatic parameters. The seasonal cumulative interception loss corresponded to 12.6–21.0% of the amount of rainfall, whereas throughfall and stemflow accounted for 77–83% and 1–6%, respectively. On a seasonal basis, simulated data fitted the measured data satisfactorily (r2 = 0.75). The rainfall partitioning between interception, throughfall and stemflow was shown to be sensitive to (1) the rainfall regime, i.e. the relative importance of light storms to total rainfall, (2) the climatic parameters, rainfall rate and average evaporation rate during storms, and (3) the canopy structure parameters of the model. The low interception rate of the canopy was attributed primarily to the low leaf area index of the stand.
Published: 1992
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102. Carbon stable isotope ratio of phloem sugars in mature pine trees throughout the growing season: comparison of two extraction methods

Author: Jaleh Ghashghaie, Arthur Gessler, Catherine Lambrot, Camille Bathellier, Marion Devaux, Didier Bert, Denis Loustau, Jérôme Ogée, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Ecologie Systématique et Evolution (ESE), Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11), Biodiversité, Gènes & Communautés (BioGeCo), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB), University of Freiburg [Freiburg], and Centre National de la Recherche Scientifique (CNRS)
Subjects: 0106 biological sciences, Sucrose, [SDV]Life Sciences [q-bio], Carbohydrates, Growing season, Centrifugation, Chemical Fractionation, Phloem, 010603 evolutionary biology, 01 natural sciences, Analytical Chemistry, 03 medical and health sciences, chemistry.chemical_compound, Sugar, ComputingMilieux_MISCELLANEOUS, Spectroscopy, 030304 developmental biology, 0303 health sciences, Carbon Isotopes, Chromatography, Pinitol, biology, Stable isotope ratio, Plant Extracts, fungi, Organic Chemistry, food and beverages, Fructose, biology.organism_classification, Pinus, chemistry, [SDE]Environmental Sciences, Pinus pinaster, Seasons
Abstract: The study presents a comparison of two phloem sugar extraction methods. The amount of phloem sugar extracted and the carbon isotope composition (delta(13)C) of the total extracts and of the main phloem compounds separated by high-performance liquid chromatography (sucrose, glucose, fructose and pinitol) are compared. These two phloem sap extraction methods are exudation in distilled water and a new method using centrifugation, which avoids the addition of any solvent. We applied both extraction methods on phloem discs sampled from 38-year-old Pinus pinaster trees in south-western France throughout the period from June 2007 to December 2008 on different time-scales: hourly, daily and monthly. We found that the centrifugation method systematically extracted ca. 50% less compounds from the phloem discs than the exudation method. In addition, the two extraction methods provided similar delta(13)C values of the total extracts, but the values obtained by the exudation method were 0.6 per thousand more negative than those calculated from the mass balance using the individual constituents. Over the growing season, both extraction methods exhibited lower total sugar content and more (13)C-enriched phloem sap in summer compared with winter values. These findings suggest that both extraction methods can be applied to study the carbon isotope composition of phloem sap, and the centrifugation method has the advantage that no solvent has to be added. The exudation method, however, is more appropriate for the quantification of the amounts of phloem sugars.
Published: 2009
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103. A single-substrate model to interpret intra-annual stable isotope signals in tree-ring cellulose

Author: Didier Bert, Roderick C. Dewar, Lisa Wingate, Monique Pierre, Denis Loustau, Alexandre Bosc, Thierry Bariac, Michel Stievenard, Jérôme Ogée, Catherine Lambrot, Margaret M. Barbour, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Manaaki Whenua – Landcare Research [Lincoln], School of GeoSciences, University of Edinburgh, Biodiversité, Gènes & Communautés (BioGeCo), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Géochrononologie Traceurs Archéométrie (GEOTRAC), Biogéochimie et écologie des milieux continentaux (Bioemco), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS)
Subjects: 0106 biological sciences, 010504 meteorology & atmospheric sciences, Physiology, Climate, Plant Science, Dendroclimatology, Oxygen Isotopes, Atmospheric sciences, OXYGEN ISOTOPE, Models, Biological, 01 natural sciences, Trees, Carbon cycle, Soil, Dendrochronology, medicine, CARBON ISOTOPE, WATER CYCLE, Cellulose, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, Carbon Isotopes, biology, Stable isotope ratio, Ecology, 15. Life on land, Seasonality, Pinus, biology.organism_classification, medicine.disease, Wood, Substrate (marine biology), Carbon, Oxygen, XYLOGENESIS, Environmental science, Pinus pinaster, CARBON CYCLE, France, Seasons, DENDROCLIMATOLOGY, 010606 plant biology & botany, Cell wall thickening
Abstract: The carbon and oxygen stable isotope composition of wood cellulose (delta(13)C(cellulose) and delta(18)O(cellulose), respectively) reveal well-defined seasonal variations that contain valuable records of past climate, leaf gas exchange and carbon allocation dynamics within the trees. Here, we present a single-substrate model for wood growth to interpret seasonal isotopic signals collected in an even-aged maritime pine plantation growing in South-west France, where climate, soil and flux variables were also monitored. Observed seasonal patterns in delta(13)C(cellulose) and delta(18)O(cellulose) were different between years and individuals, and mostly captured by the model, suggesting that the single-substrate hypothesis is a good approximation for tree ring studies on Pinus pinaster, at least for the environmental conditions covered by this study. A sensitivity analysis revealed that the model was mostly affected by five isotopic discrimination factors and two leaf gas-exchange parameters. Modelled early wood signals were also very sensitive to the date when cell wall thickening begins (t(wt)). Our model could therefore be used to reconstruct t(wt) time series and improve our understanding of how climate influences this key parameter of xylogenesis.
Published: 2009
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104. Contributions of climate, leaf area index and leaf physiology to variation in gross primary production of six coniferous forests across Europe: a model-based analysis

Author: Paul Berbigier, Hans Verbeeck, Annikki Mäkelä, Pasi Kolari, Thomas Grünwald, Denis Loustau, Timo Vesala, Minna Pulkkinen, Meelis Mölder, Mika Aurela, Eero Nikinmaa, C. Bernhofer, Martti Perämäki, Remko A. Duursma, Pertti Hari, University of Helsinki, Finnish Meteorological Institute (FMI), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Lund University [Lund], Research Group of Plant and Vegetation Ecology - Department of Biology, University of Antwerp (UA), Laboratory of Plant Ecology, Department of Applied Ecology and Environmental Biology, and Universiteit Gent = Ghent University [Belgium] (UGENT)
Subjects: 0106 biological sciences, PROCESS-BASED MODEL, 010504 meteorology & atmospheric sciences, PRODUCTION PRIMAIRE, Physiology, Climate, Plant Science, Models, Biological, 01 natural sciences, Trees, FOREST CARBON UPTAKE, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Forest ecology, medicine, Ecosystem, Photosynthesis, Leaf area index, Biology, 0105 earth and related environmental sciences, Geography, Temperature, Temperate forest, Primary production, Carbon sink, FOREST PRODUCTIVITY, 15. Life on land, Seasonality, medicine.disease, Photosynthetic capacity, Carbon, Europe, Plant Leaves, Tracheophyta, 13. Climate action, Environmental science, INDICE FOLIAIRE, 010606 plant biology & botany
Abstract: International audience; Gross primary production (GPP) is the primary source of all carbon fluxes in the ecosystem. Understanding variation in this flux is vital to understanding variation in the carbon sink of forest ecosystems, and this would serve as input to forest production models. Using GPP derived from eddy-covariance (EC) measurements, it is now possible to determine the most important factor to scale GPP across sites. We use long-term EC measurements for six coniferous forest stands in Europe, for a total of 25 site-years, located on a gradient between southern France and northern Finland. Eddy-derived GPP varied threefold across the six sites, peak ecosystem leaf area index (LAI) (all-sided) varied from 4 to 22 m2 m-2 and mean annual temperature varied from -1 to 13C. A process-based model operating at a half-hourly time-step was parameterized with available information for each site, and explained 71-96% in variation between daily totals of GPP within site-years and 62% of annual total GPP across site-years. Using the parameterized model, we performed two simulation experiments: weather datasets were interchanged between sites, so that the model was used to predict GPP at some site using data from either a different year or a different site. The resulting bias in GPP prediction was related to several aggregated weather variables and was found to be closely related to the change in the effective temperature sum or mean annual temperature. High R 2s resulted even when using weather datasets from unrelated sites, providing a cautionary note on the interpretation of R 2 in model comparisons. A second experiment interchanged stand-structure information between sites, and the resulting bias was strongly related to the difference in LAI, or the difference in integrated absorbed light. Across the six sites, variation in mean annual temperature had more effect on simulated GPP than the variation in LAI, but both were important determinants of GPP. A sensitivity analysis of leaf physiology parameters showed that the quantum yield was the most influential parameter on annual GPP, followed by a parameter controlling the seasonality of photosynthesis and photosynthetic capacity. Overall, the results are promising for the development of a parsimonious model of GPP.
Published: 2009
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105. Adaptation of fine roots to annual fertilization and irrigation in a 13-year-old Pinus pinaster stand

Author: Mark R. Bakker, Jacques Guinberteau, E. Jolicoeur, P. Trichet, Laurent Augusto, Denis Loustau, Claude Plassard, Transfert Sol-Plante et Cycle des Eléments Minéraux dans les Ecosystèmes Cultivés (TCEM), Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB), Université de Moncton, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Ecologie Fonctionnelle et Biogéochimie des Sols (Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Ecole Nationale Supérieure Agronomique de Montpellier (ENSA M), and Unité de recherche Mycologie et Sécurité des Aliments (MycSA)
Subjects: 0106 biological sciences, Irrigation, ROOT TO SHOOT RATIOS, Physiology, HYPHAE, Plant Science, Root system, engineering.material, Biology, 01 natural sciences, Plant Roots, Trees, Nutrient, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, FINE ROOT DENSITY, Mycorrhizae, Fertilizers, 2. Zero hunger, Water, PIN MARITIME, Phosphorus, FINE ROOT MORPHOLOGY, 04 agricultural and veterinary sciences, 15. Life on land, biology.organism_classification, Pinus, 6. Clean water, Plant Leaves, ANNUAL RESOURCE OPTIMIZATION, Agronomy, Shoot, 040103 agronomy & agriculture, engineering, 0401 agriculture, forestry, and fisheries, Soil horizon, Pinus pinaster, Fertilizer, 010606 plant biology & botany, Woody plant
Abstract: International audience; Effects of fertilization and irrigation on fine roots and fungal hyphae were studied in 13-year-old maritime pine (Pinus pinaster Aït. in Soland), 7 years after the initiation of the treatments. The fertilization trials consisted of a phosphorus treatment, a complete fertilizer treatment (N, P, K, Ca and Mg), and an unfertilized treatment (control). Fertilizers were applied annually and were adjusted according to foliar target values. Two irrigation regimes (no irrigation and irrigation of a set amount each day) were applied from May to October. Root samples to depths of 120 cm were collected in summer of 2005, and the biomass of small roots (diameter 2–20 mm) and fine roots (diameter ≤ 2 mm) and fine root morphology were assessed. Biomass and length of hyphae were studied by a mesh ingrowth bag technique. Total fine root biomass in the litter and in the 0–120 cm soil profile ranged between 111 and 296 g m–2. Results derived from the measurements of biomass and root length, or root area, showed that both fertilizer treatments reduced the size of the fine root system, especially in the top soil layers, but did not affect small roots. Compared with control treatments, fine root morphology was affected by both fertilizer treatments with the fine roots having increased specific root length/area, and irrigation tended to reinforce this finer morphology. The amount of hyphae in the mesh ingrowth bags was higher in the fertilization and irrigation treatments than in the controls, suggesting further extension of the root system (ectomycorrhizal infection) and thus of the uptake system. Irrigation had no significant effect on the size of the fine root system, but resulted in a shallower rooting system. Total root to shoot ratios were unaffected by the treatments, but fine root mass:needle mass and fine root area index:leaf area index ratios decreased with increasing nutrient supply. Overall, compared with the control fine roots, increased nutrient supply resulted in a lower fine root biomass but the dynamic fraction of the finest roots was greater. Irrigation had only limited effects on fine root size, distribution and morphology.
Published: 2009
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106. Étude microclimatique de l'effet de la sécheresse sur l'évaporation d'une plantation de pins maritimes et du sous-bois

Author: Denis Loustau, A Diawara, Paul Berbigier, and Revues Inra, Import
Subjects: Plant Science, [SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, ComputingMilieux_MISCELLANEOUS
Abstract: L'evapotranspiration d'une plantation de pin maritime a ete suivie dans les Landes pendant la secheresse de l'annee 1989 (mai-septembre), par une methode microclimatique de bilan d'energie-fluctuations et la methode du debit de seve. Les methodes mathematiques de description de la regulation stomatique au niveau des arbres et du sous-bois sont discutees. Les evolutions des moyennes horaires des conductances de surface et leurs relations avec le rapport de l'evapotranspiration au rayonnement net absorbe par chaque strate (LE/R n ) pendant la phase diurne sont etudiees. Les valeurs journalieres de LE/R n pour les pins semblent dependre du stock d'eau du sol (0-75 cm)
Published: 1991
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107. Carbon dioxide and energy flux partitioning between the understorey and the overstorey of a maritime pine forest during a year with reduced soil water availability

Author: Denis Loustau, Eric Lamaud, Jean-Marc Bonnefond, M. Irvine, Nathalie Jarosz, Yves Brunet, Écologie fonctionnelle et physique de l'environnement (EPHYSE - UR1263), Institut National de la Recherche Agronomique (INRA), and Écologie fonctionnelle et physique de l'environnement (EPHYSE)
Subjects: 0106 biological sciences, Atmospheric Science, 010504 meteorology & atmospheric sciences, conifer forest, Eddy covariance, Sensible heat, 01 natural sciences, Sink (geography), Latent heat, eddy covariance, H2O, Ecosystem, WUE, Water content, 0105 earth and related environmental sciences, Hydrology, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, Global and Planetary Change, geography, geography.geographical_feature_category, Forestry, 15. Life on land, 13. Climate action, Soil water, Environmental science, CO2, GPP, Ecosystem respiration, Agronomy and Crop Science, respiration, 010606 plant biology & botany
Abstract: International audience; Carbon dioxide, water vapour and energy fluxes were measured above and within a maritime pine forest during an atypical year with long-lasting reduced soil water availibility. Energy balance closure was adequately good at both levels. As compared with what is usually observed at this site the ecosystem dissipated less energy via latent heat flux and more via sensible heat flux. The understorey canopy was responsible for a variable, significant component of the whole canopy fluxes of water vapour and carbon dioxide. The annual contribution of the understorey was 38% (154 mm) of the overall evaporation (399 mm) and 32% (89 mm) of the overall sensible heat flux (274 mm). The participation of the understorey reached 45% of the overall evaporation and 30% of the daytime overall assimilation during significant soil water deficit periods in summertime. Even during winter, understorey photosynthesis was consistent as it compensated soil and understorey respiration. The ecosystem behaved as a sink of carbon, with a negative annual carbon budget (-57 gC m-2). However, due to high soil water deficit, the annual ecosystem GPP was 40% less than usually observed at this site. This budget resulted from a sink of -131 gC m-2 for the overstorey and a source of +74 gC m-2 for the understorey. Moreover, on an annual basis the overstorey layer contributed to almost two thirds of the ecosystem respiration. Finally, the effect of long-lasting soil water deficit on the maritime pine forest was found more important than the effect of the heat wave and drought of summer 2003.
Published: 2008
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108. Impacts of climate change on temperate forests and interaction with management

Author: Denis Loustau, Jérôme Ogée, Michel Déqué, Jean-Luc Dupouey, Vincent BADEAU, Nicolas Viovy, Philippe Ciais, Marie Laure Desprez Loustau, Alain Roques, Isabelle Chuine, Florent Mouillot, ProdInra, Migration, Peter Freer-Smith (Editeur), Mark Broadmeadow (Editeur), Jim Lynch (Editeur), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Météo France, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Biodiversité, Gènes & Communautés (BioGeCo), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB), Unité de recherche Zoologie Forestière (URZF), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Institut de Recherche pour le Développement (IRD), Météo-France Direction Interrégionale Sud-Est (DIRSE), Météo-France, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)
Subjects: [SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, [SDV]Life Sciences [q-bio], CYCLES BIOGEOCHIMIQUES, [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS, ECOLOGIE
Abstract: International audience
Published: 2008

109. Improving models of forest nutrient export with equations that predict the nutrient concentration of tree compartments

Author: Pierre Trichet, J. Gelpe, Frédéric Lagane, Frédéric Danjon, Céline Meredieu, Didier Bert, Sylvain Pellerin, Denis Loustau, Annabel J. Porté, Laurent Augusto, Jacques Ranger, Alexandre Bosc, Transfert Sol-Plante et Cycle des Eléments Minéraux dans les Ecosystèmes Cultivés (TCEM), Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Biodiversité, Gènes & Communautés (BioGeCo), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB), Unité de recherche Biogéochimie des Ecosystèmes Forestiers (BEF), and Revues Inra, Import
Subjects: 0106 biological sciences, Forest management, chemistry.chemical_element, NUTRIENT, 01 natural sciences, landes, Nutrient, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, DENDROMETRIE DE L'ARBRE, Botany, biomasse, aquitaine, TREE DIMENSION, ComputingMilieux_MISCELLANEOUS, Biomass (ecology), Stem bark, pinus pinaster, Ecology, biology, PIN MARITIME, Forestry, 04 agricultural and veterinary sciences, 15. Life on land, NUTRIMENT, biology.organism_classification, Nitrogen, EXPORT, EXPORTATION, chemistry, Agronomy, visual_art, 040103 agronomy & agriculture, visual_art.visual_art_medium, 0401 agriculture, forestry, and fisheries, Pinus pinaster, Bark, [SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Tree species, analyse chimique, 010606 plant biology & botany
Abstract: International audience; The objective of this study was to explore the distribution of major nutrients (N, P, K, Ca and Mg) in the aboveground compartments of an intensively managed tree species (Pinus pinaster Ait.). A total of 53 trees were cut down in even-aged stands respectively 8, 16, 26, 32 and 40 years old. The nutrient concentrations of the aboveground compartments were analysed. Nutrient concentrations of foliage did not vary with any of the variables used, except needle age. Nutrient concentrations of living branches, stem bark, stem sapwood, stem heartwood, stemwood and stem decreased with increasing branch diameter, bark thickness, sapwood thickness and heartwood thickness, respectively. Beyond a certain value of the predictive variable (stem diameter approximate to 15 cm; branch diameter approximate to 2.5 cm), the concentration of all the nutrients stabilised. A 50 year-old pine stand was used to obtain a validation dataset for nitrogen concentration. For this nutrient, the regression relationships gave satisfactory estimates for most compartments (mean error = 12-25%) and particularly for the stem. A procedure is proposed to estimate the nutrient exports associated with harvests of Pinus pinaster biomass.
Published: 2008
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110. Forests, Carbon Cycle and Climate Change

Author: Denis Loustau and Denis Loustau
Subjects: Carbon cycle (Biogeochemistry)--France, Biogeochemical cycles--France
Abstract: This Print On Demand book will be sent within 3 weeks (metropolitan France) and in a separate package if you order another paperback book.Cet ouvrage en impression à la demande sera envoyé sous 3 semaines environ (France métropolitaine) et dans un colis séparé en cas de commande avec un autre livre papier.Les résultats présentés dans ce livre résument les principales observations du projet CARBOFOR, qui a réuni 52 scientifiques de 14 unités de recherche afin d'étudier les effets futurs du climat sur le cycle du carbone, la productivité et la vulnérabilité des forêts françaises. Ce livre expose le cycle du carbone actuel dans les forêts des climats tempérés et méditerranéens, la dynamique du carbone dans le sol et le stock total de carbone dans les forêts françaises, d'après les inventaires forestiers. Il donne un aperçu et illustre les principales méthodes de terrain permettant d'évaluer les stocks de carbone au sein de la biomasse des arbres. Des variations spatiales dans un schéma de changement climatique en France métropolitaine au cours du 21ème siècle sont décrits. Le livre prend ensuite en considération l'effet du changement climatique sur la phénologie des arbres et l'équilibre en carbone, l'évapotranspiration et la production d'une forêt ainsi que leur interaction de premier niveau avec les alternatives en matière de gestion forestière. L'effet du changement climatique sur la vulnérabilité de la forêt est analysée. Une étude de simulation similaire a été effectuée pour certains champignons pathogènes, en mettant l'accent tant sur le réchauffement que sur les modifications de pluviométrie. Les conséquences du changement climatique sur l'apparition d'incendies et sur le cycle du carbone des forêts dans la zone méditerranéenne sont également prises en compte. Une référence de valeur pour les chercheurs et les académiciens, les ingénieurs et les gestionnaires des eaux et forêts, ainsi que les étudiants en dernière année d'école d'écologie forestière, de modélisation écologique et de sylviculture.
Published: 2010

111. CO2 balance of boreal, temperate, and tropical forests derived from a global database

Author: Jeffrey Q. Chambers, Eero Nikinmaa, Richard Harding, Philippe Ciais, Carlos A. Sierra, Timo Vesala, Gabriel Pita, S. L. Piao, T. Laurila, Pasi Kolari, Andrew D. Richardson, G. Le Maire, Paul J. Hanson, Scott V. Ollinger, Guenther Seufert, Lisa Wingate, Ivan A. Janssens, Timothy J. Griffis, Achim Grelle, J. W. Munger, Bruce D. Cook, Olivier Roupsard, David Y. Hollinger, Kenneth J. Davis, Dario Papale, Sebastiaan Luyssaert, Christian Bernhofer, Jean-Marc Bonnefond, Marc Aubinet, Damien Bonal, Thomas Grünwald, Markus Reichstein, Corinna Rebmann, Denis Loustau, Gabriele Guidolotti, I. Inglima, Laurent Misson, Lucy R. Hutyra, Fredrik Lagergren, Ernst Detlef Schulze, J. Mateus, Werner L. Kutsch, Martin Jung, Leonardo Montagnani, Anders Lindroth, María José Sanz, A. Granier, Jianwu Tang, Mirco Migliavacca, Giorgio Matteucci, Eddy Moors, John Moncrieff, Yadvinder Malhi, Beverly E. Law, John Grace, Marie-Louise Smith, Birgit Gielen, Kevin Black, Michael L. Goulden, Christian Beer, Riccardo Valentini, A. J. Dolman, Nobuko Saigusa, Bart Kruijt, Luiz E. O. C. Aragão, Department of Biology, University of Antwerp (UA), Centre Interdisciplinaire de Recherche Ions Lasers (CIRIL), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Faculty of Information Sciences and Engineering, University of Canberra, Department of Biogeochemical Integration [Jena], Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Department of Forest Environment and Resources, University of Tuscia, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China, affiliation inconnue, Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China, Max-Planck-Institut für Biogeochemie (MPI-BGC), Écologie fonctionnelle et physique de l'environnement (EPHYSE - UR1263), Institut National de la Recherche Agronomique (INRA), CNR-ISAFOM, School of Geography and the Environment, Environmental Change Institute, University of Oxford [Oxford], AgroBio Tech GxABT, Univ Liege Gembloux Agrobio Tech, Tech Univ Dresden, Inst Hydrol and Meteorol, Dept Meteorol, D-01737 Tharandt, Germany, Ecologie des forêts de Guyane (ECOFOG), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Ecology and Evolutionary Biology, Tulane University, University of New Orleans, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Georgia Institute of Technology [Atlanta], PennState Meteorology Department, Pennsylvania State University (Penn State), Penn State System-Penn State System, Faculty of Earth and Life Sciences [Amsterdam] (FALW), Vrije Universiteit Amsterdam [Amsterdam] (VU), Research Group of Plant and Vegetation Ecology, School of Geosciences [Edinburgh], University of Edinburgh, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Department of Ecology, Uppsala, Uppsala University, Department soil, water & climate, University of Minnesota [Twin Cities], University of Minnesota System-University of Minnesota System, Department of Computer Science [Dresden], Technische Universität Dresden (TUD), Centre for Ecology and Hydrology [Wallingford] (CEH), Natural Environment Research Council (NERC), NE Research Station, USDA Forest Service, Urban Design and Planning, University of Washington [Seattle], Forest Ecology and Management [Helsinki], Department of Forest Sciences [Helsinki], Faculty of Agriculture and Forestry [Helsinki], University of Helsinki-University of Helsinki-Faculty of Agriculture and Forestry [Helsinki], University of Helsinki-University of Helsinki, Earth System Science-Climate Change, Centre for Water and Climate [Wageningen], Max-Planck-Gesellschaft, Department of Physical Geography and Ecosystem Science [Lund], Lund University [Lund], Finnish Meteorological Institute (FMI), College of Forestry, Oregon State University (OSU), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Unité de Recherches Forestières, Environmental Change Institute, School of Geography and the Environment, Imperial College London, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Servizi Forestali, Provincia Autonoma di Bolzano, Agenzia per l'Ambiente, Alterra [Wageningen] (ESS-CC), Department of Earth and Planetary Sciences [Cambridge, USA] (EPS), Harvard University [Cambridge], Analyse et Traitement Informatique de la Langue Française (ATILF), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), National Cancer Institute [Bethesda] (NCI-NIH), National Institutes of Health [Bethesda] (NIH), Fonctionnement et pilotage des écosystèmes de plantations (Cirad-Persyst-UPR 80 Ecosystèmes de plantations), Département Performances des systèmes de production et de transformation tropicaux (Cirad-PERSYST), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Department of Forest Science and Environment, Department of Physical Sciences [Helsinki], University of Helsinki, Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University [Beijing], Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institute of Hydrology and Meteorology [Tharandt], Technische Universität Dresden = Dresden University of Technology (TU Dresden), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), ICOS-ATC (ICOS-ATC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Department of Ecology, Swedish University of Agricultural Sciences (SLU), University of Minnesota [Twin Cities] (UMN), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Unité de recherches forestières (BORDX PIERR UR ), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Fonctionnement et pilotage des écosystèmes de plantations (UPR Ecosystèmes de plantations), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Università degli studi della Tuscia [Viterbo], University of Oxford, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Helsingin yliopisto = Helsingfors universitet = University of Helsinki-Helsingin yliopisto = Helsingfors universitet = University of Helsinki-Faculty of Agriculture and Forestry [Helsinki], Helsingin yliopisto = Helsingfors universitet = University of Helsinki-Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Harvard University, Helsingin yliopisto = Helsingfors universitet = University of Helsinki, and Hydrology and Geo-environmental sciences
Subjects: 0106 biological sciences, F40 - Écologie végétale, 010504 meteorology & atmospheric sciences, P40 - Météorologie et climatologie, [SDV]Life Sciences [q-bio], Biome, Atmospheric carbon cycle, Carbon sequestration, computer.software_genre, 01 natural sciences, SDG 17 - Partnerships for the Goals, carbon cycle, Forest ecology, SDG 13 - Climate Action, forest ecosystems, global database, gross primary productivity, net ecosystem productivity, net primary productivity, Environmental Chemistry, Ecosystem, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, General Environmental Science, Global and Planetary Change, Ecology, Database, Primary production, 15. Life on land, C30 - Documentation et information, 13. Climate action, Environmental science, Terrestrial ecosystem, [SDV.EE.BIO]Life Sciences [q-bio]/Ecology, environment/Bioclimatology, Ecosystem ecology, computer, 010606 plant biology & botany
Abstract: International audience; Terrestrial ecosystems sequester 2.1 Pg of atmospheric carbon annually. A large amount of the terrestrial sink is realized by forests. However, considerable uncertainties remain regarding the fate of this carbon over both short and long timescales. Relevant data to address these uncertainties are being collected at many sites around the world, but syntheses of these data are still sparse. To facilitate future synthesis activities, we have assembled a comprehensive global database for forest ecosystems, which includes carbon budget variables (fluxes and stocks), ecosystem traits (e.g. leaf area index, age), as well as ancillary site information such as management regime, climate, and soil characteristics. This publicly available database can be used to quantify global, regional or biome-specific carbon budgets; to re-examine established relationships; to test emerging hypotheses about ecosystem functioning [e.g. a constant net ecosystem production (NEP) to gross primary production (GPP) ratio]; and as benchmarks for model evaluations. In this paper, we present the first analysis of this database. We discuss the climatic influences on GPP, net primary production (NPP) and NEP and present the CO2 balances for boreal, temperate, and tropical forest biomes based on micrometeorological, ecophysiological, and biometric flux and inventory estimates. Globally, GPP of forests benefited from higher temperatures and precipitation whereas NPP saturated above either a threshold of 1500 mm precipitation or a mean annual temperature of 10 degrees C. The global pattern in NEP was insensitive to climate and is hypothesized to be mainly determined by nonclimatic conditions such as successional stage, management, site history, and site disturbance. In all biomes, closing the CO2 balance required the introduction of substantial biome-specific closure terms. Nonclosure was taken as an indication that respiratory processes, advection, and non-CO2 carbon fluxes are not presently being adequately accounted for.
Published: 2007
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112. L’observation des effets du changement global sur les écosystèmes continentaux

Author: Denis Loustau, Écologie fonctionnelle et physique de l'environnement (EPHYSE), and Institut National de la Recherche Agronomique (INRA)
Subjects: changement climatique, réseau d'observation, productivité, télédétection, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, écosystème, phénologie, ComputingMilieux_MISCELLANEOUS, écosystème forestier
Abstract: National audience
Published: 2007

113. Carbon sequestration in terrestrial ecosystems: facts and methods

Author: Denis Loustau, Écologie fonctionnelle et physique de l'environnement (EPHYSE), and Institut National de la Recherche Agronomique (INRA)
Subjects: cycle du carbone, [SDE.MCG]Environmental Sciences/Global Changes, bilan de carbone, Milieux et Changements globaux, écosystème, ComputingMilieux_MISCELLANEOUS
Abstract: National audience
Published: 2007

114. Impact du changement climatique sur la production des forêts françaises : résultats du projet CARBOFOR

Author: Alexandre Bosc, Denis Loustau, Jérôme Ogée, Hendrik Davi, Christophe François, Michel Déqué, Christine Le Bas, Nicolas Saby, Gérome Pignard, Nabila Hamza, Nicolas Viovy, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Ecologie Systématique et Evolution (ESE), Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), InfoSol (InfoSol), Inventaire Forestier National (IFN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: National audience
Published: 2007

115. Spring and autumnal P availability, fine root properties and functional mycorrhizal diversity across Pinus pinaster stands with different productivity in southwest France

Author: Claude Plassard, Mark Ronald Bakker, Pierre Trichet, Céline Meredieu, Frederic Danjon, Jacques Guinberteau, Laurent AUGUSTO, Etienne Saur, Odile Domergue, Antoine Galiana, Yves Prin, Arif Ali Muhammad, Philippe Hinsinger, Benoît Jaillard, Sylvain Pellerin, Denis Loustau, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Transfert Sol-Plante et Cycle des Eléments Minéraux dans les Ecosystèmes Cultivés (TCEM), Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Unité de recherche Mycologie et Sécurité des Aliments (MycSA), Laboratoire des symbioses tropicales et méditerranéennes (UMR LSTM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Montpellier 1 (UM1)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)
Subjects: pinus pinaster, [SDV]Life Sciences [q-bio], PIN MARITIME, P34 - Biologie du sol, F50 - Anatomie et morphologie des plantes, fertilisation, landes, phosphore, F62 - Physiologie végétale : croissance et développement, K10 - Production forestière, racine, mycorhize, productivité, [SDE]Environmental Sciences, aquitaine, ComputingMilieux_MISCELLANEOUS
Abstract: The Pinus pinaster forest in south west France covers 0.9 million hectares, mainly on acidic sandy, nutrient-poor spodosols. This forest produces the fifth of French wood and is characterized by a large variation in productivity. We aimed at linking these variations to plant root, mycorrhizal parameters and nutritional soil status. Twenty-seven sites were selected so as to cover a range of site productivity, phosphorus and nitrogen fertility and water availability levels. These include fertilizer trials and other monitoring sites both on humid and dry environments. Site productivity was estimated from a standard forest inventory operated in 2005. In April and November 2006 eight pairs of sample points were chosen in the tree lines and between the tree lines closeto randomly distributed trees. Soil P status (Olsen P and total organic P), diversity and phosphatase activities of ectomycorrhizae (ECM) and their associated bacteria were determined in 15x8 cm cylindric soil cores. Also, the following root parameters were measured: Fine Root Length Density (FRLD), Specific Root Length (SRL), vitality of apices and ECM colonization degree. Grouping samples according to sample position, fertilization, stand age or water availability shows that both P forms were greater in April than in November. Olsen P level was significantly higher only between the tree lines of annually fertilized plots compared to all other plots. All root parameters were significantly higher in November than in April. Only SRL and vitality of apices increased as a response to P fertilization. On the contrary, P-solubilizing capacities of mycorrhizospheric bacteria were greater in control plots with no P fertilizer. ECM pNPPase activities were always measurable and tended to decrease as a response to intensive fertilization. Differences between sites were striking. Although multivariate statistical analyses should help us to draw the relationships between tree productivity, biotic and abiotic factors in the root environment, our first results suggest that biotic parameters may be more sensitive than physical parameters to sylvicultural treatments and environmental conditions. (Texte intégral)
Published: 2007

116. Evidence for soil water control on carbon and water dynamics in European forests during the extremely dry year: 2003

Author: Hannu Ilvesniemi, Markus Reichstein, C. Nys, Corinna Rebmann, André Granier, Qiuwang Wang, Marianne Peiffer, Bernard Longdoz, Eddy Moors, B. Heinesch, Fredrik Lagergren, Gabriel Pita, Philippe Ciais, Timo Vesala, Serge Rambal, J. Mateus, Leonardo Montagnani, Kim Pilegaard, Anders Lindroth, Osvaldo Facini, Denis Loustau, Giacomo Grassi, Paul Berbigier, Alexander Knohl, Barbara Köstner, John Tenhunen, Petri Keronen, Abel Rodrigues, Jukka Pumpanen, M. Aubinet, Thomas Grünwald, Guenther Seufert, Ivan A. Janssens, Dario Papale, Nathalie Bréda, Eva Falge, Christian Bernhofer, Nina Buchmann, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Università degli studi della Tuscia [Viterbo], Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft, Department of Biology, University of Antwerp (UA), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ICOS-ATC (ICOS-ATC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Unité de Physique, Faculté Universitaire des Sciences Agronomiques de Gembloux, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Institute of Plant Sciences, National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Institute for Environment and Sustainability of the JRC, Partenaires INRAE, Finnish Forest Research Institute, Helsingin yliopisto = Helsingfors universitet = University of Helsinki, University of California [Berkeley] (UC Berkeley), University of California (UC), Lund University [Lund], Instituto Superior Técnico, Agenzia Provinciale per l’Ambiente, Ripartizione Foreste di Bolzano, Unité de recherche Biogéochimie des Ecosystèmes Forestiers (BEF), Wageningen University and Research Centre (WUR), Risø National Laboratory for Sustainable Energy (Risø DTU), Danmarks Tekniske Universitet = Technical University of Denmark (DTU), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Estaçao Florestal Nacional, Tuscia University, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Consiglio Nazionale delle Ricerche (CNR), University of Helsinki, University of California [Berkeley], University of California, Technical University of Denmark [Lyngby] (DTU), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud])
Subjects: 0106 biological sciences, Atmospheric Science, 010504 meteorology & atmospheric sciences, drought, 01 natural sciences, Water balance, water balance, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, boreal aspen forest, Alterra - Centre for Water and Climate, net ecosystem carbon balance, Wageningen Environmental Research, waterbalans, fagus-sylvatica l, beech forest, Transpiration, scots pine, Global and Planetary Change, Ecology, food and beverages, Forestry, deciduous forest, Throughfall, west-europa, Carbon and water fluxes, Soil horizon, severe drought, Ecosystem respiration, Interception, leaf-area index, Alterra - Centrum Water en Klimaat, soil water, netto ecosysteem koolstofbalans, Modelling, droogte, Forest, 0105 earth and related environmental sciences, forests, Hydrology, Drought, fungi, Primary production, ecosystem co2 exchange, bodemwater, 15. Life on land, sap flow measurements, 13. Climate action, Soil water, Environmental science, canopy conductance, bossen, Agronomy and Crop Science, western europe, 010606 plant biology & botany
Abstract: International audience; The drought of 2003 was exceptionally severe in many regions of Europe, both in duration and in intensity. In some areas, especially in Germany and France, it was the strongest drought for the last 50 years, lasting for more than 6 months. We used continuous carbon and water flux measurements at 12 European monitoring sites covering various forest ecosystem types and a large climatic range in order to characterise the consequences of this drought on ecosystems functioning. As soil water content in the root zone was only monitored in a few sites, a daily water balance model was implemented at each stand to estimate the water balance terms: trees and understorey transpiration, rainfall interception, throughfall, drainage in the different soil layers and soil water content. This model calculated the onset date, duration and intensity of the soil water shortage (called water stress) using measured climate and site properties: leaf area index and phenology that both determine tree transpiration and rainfall interception, soil characteristics and root distribution, both influencing water absorption and drainage. At sites where soil water content was measured, we observed a good agreement between measured and modelled soil water content. Our analysis showed a wide spatial distribution of drought stress over Europe, with a maximum intensity within a large band extending from Portugal to NE Germany. Vapour fluxes in all the investigated sites were reduced by drought, due to stomatal closure, when the relative extractable water in soil (REW) dropped below ca. 0.4. Rainfall events during the drought, however, typically induced rapid restoration of vapour fluxes. Similar to the water vapour fluxes, the net ecosystem production decreased with increasing water stress at all the sites. Both gross primary production (GPP) and total ecosystem respiration (TER) also decreased when REW dropped below 0.4 and 0.2, for GPP and TER, respectively. A higher sensitivity to drought was found in the beech, and surprisingly, in the broadleaved Mediterranean forests; the coniferous stands (spruce and pine) appeared to be less drought-sensitive. The effect of drought on tree growth was also large at the three sites where the annual tree growth was measured. Especially in beech, this growth reduction was more pronounced in the year following the drought (2004). Such lag effects on tree growth should be considered an important feature in forest ecosystems, which may enhance vulnerability to more frequent climate extremes. (c) 2007 Elsevier B.V. All rights reserved.
Published: 2007
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117. The likely impact of elevated [CO2], nitrogen deposition, increased temperature and management on carbon sequestration in temperate and boreal forest ecosystems: a literature review

Author: Denis Loustau, Achim Grelle, Göran I. Ågren, Tornas Lundmark, Seppo Kellomäki, Marcel van Oijen, M. Francesca Cotrufo, Ritta Hyvönen, Tryggve Persson, Ivan A. Janssens, Göran Wallin, Rarn Oren, Paul Jarvis, Anders Lindroth, Michael G. Ryan, Alf Ekblad, Bjarni D. Sigurdsson, Monika Strömgren, Kim Pilegaard, Richard J. Norby, Sune Linder, Michael Freeman, Swedish University of Agricultural Sciences (SLU), Southern Swedish Forest Research Centre, Seconda Università degli studi di Napoli, Örebro University, University of Antwerp (UA), University of Joensuu, Lund University [Lund], Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Environmental Sciences Division [Oak Ridge], Oak Ridge National Laboratory [Oak Ridge] (ORNL), UT-Battelle, LLC-UT-Battelle, LLC, Duke University [Durham], Technical University of Denmark [Lyngby] (DTU), Forest Service, United States Department of Agriculture, University of Iceland, Natural Environment Research Council (NERC), Department of Plant and Environmental Sciences, and University of Gothenburg (GU)
Subjects: 0106 biological sciences, 010504 meteorology & atmospheric sciences, Nitrogen, Physiology, Growing season, Plant Science, Carbon sequestration, 01 natural sciences, Trees, Forest ecology, Temperate climate, Ecosystem, Nitrogen cycle, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, 2. Zero hunger, Ecology, Soil organic matter, Temperature, Primary production, Carbon Dioxide, 15. Life on land, Carbon, [SDV.BV.PEP]Life Sciences [q-bio]/Vegetal Biology/Phytopathology and phytopharmacy, Agronomy, 13. Climate action, Environmental science, 010606 plant biology & botany
Abstract: Temperate and boreal forest ecosystems contain a large part of the carbon stored on land, in the form of both biomass and soil organic matter. Increasing atmospheric [CO2], increasing temperature, elevated nitrogen deposition and intensified management will change this C store. Well documented single-factor responses of net primary production are: higher photosynthetic rate (the main [CO2] response); increasing length of growing season (the main temperature response); and higher leaf-area index (the main N deposition and partly [CO2] response). Soil organic matter will increase with increasing litter input, although priming may decrease the soil C stock initially, but litter quality effects should be minimal (response to [CO2], N deposition, and temperature); will decrease because of increasing temperature; and will increase because of retardation of decomposition with N deposition, although the rate of decomposition of high-quality litter can be increased and that of low-quality litter decreased. Single-factor responses can be misleading because of interactions between factors, in particular those between N and other factors, and indirect effects such as increased N availability from temperature-induced decomposition. In the long term the strength of feedbacks, for example the increasing demand for N from increased growth, will dominate over short-term responses to single factors. However, management has considerable potential for controlling the C store.
Published: 2007
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118. Reduction of ecosystem productivity and respiration during the European summer 2003 climate anomaly: a joint flux tower, remote sensing and modelling analysis

Author: Werner L. Kutsch, Vincent Allard, Alexander Knohl, Martin Heimann, Guenther Seufert, Giovanni Manca, Jean-Marc Ourcival, Riccardo Valentini, Nina Buchmann, Jérôme Ogée, Philippe Ciais, Serge Rambal, Dario Papale, Timo Vesala, Wolfgang Cramer, Denis Loustau, Jukka Pumpanen, M. Aubinet, Bernard Heinesch, Thomas Grünwald, Steven W. Running, André Granier, Sibyll Schaphoff, Maosheng Zhao, Ch. Bernhofer, Nicolas Viovy, María José Sanz, Jean-François Soussana, Franco Miglietta, Markus Reichstein, Arnaud Carrara, Kim Pilegaard, Giorgio Matteucci, Department of Biogeochemical Integration [Jena], Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Department of Forest Environment and Resources (DISAFRI), University of Tuscia, Montana State University (MSU), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Écologie fonctionnelle et physique de l'environnement (EPHYSE - UR1263), Institut National de la Recherche Agronomique (INRA), INRA Clermont-Ferrand (INRA Clermont), Unité de Physique des Biosystèmes, unité de physique, Faculté des Sciences Agronomiques, Académie universitaire Wallonie-Europe, CNR-CSITE, Institute of Hydrology and Meteorology, Max-Planck-Gesellschaft, Université de Liège, Georg-August-University [Göttingen], Johann Heinrich von Thünen-Institut, Interactions Sol Plante Atmosphère (ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institute of agroenvironmental and forest biology (CNR-IBAF), School of Architecture, Civil and Environmental Engineering (ENAC), Laboratory of Ecohydrology (ECHO), Ecole Polytechnique Fédérale de Lausanne (EPFL), Biosystems Division [Roskilde], Risø National Laboratory for Sustainable Energy (Risø DTU), Technical University of Denmark [Lyngby] (DTU)-Technical University of Denmark [Lyngby] (DTU), University of Helsinki, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Potsdam Institute for Climate Impact Research (PIK), European Commission, Unité Mixte de Recherche sur l'Ecosystème Prairial - UMR (UREP), Institut National de la Recherche Agronomique (INRA)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS), Institut des Sciences Moléculaires de Marseille (ISM2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), European Project: 28980,CARBOEUROPE-IP, European Project: 0639235(2007), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), ICOS-ATC (ICOS-ATC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modélisation des Surfaces et Interfaces Continentales (MOSAIC), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Interactions Sol Plante Atmosphère (UMR ISPA), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Unité de recherche Agronomie de Clermont (URAC), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Università degli studi della Tuscia [Viterbo], Danmarks Tekniske Universitet = Technical University of Denmark (DTU)-Danmarks Tekniske Universitet = Technical University of Denmark (DTU), Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Fundacion CEAM, University of California [Berkeley] (UC Berkeley), University of California (UC), CNR-ISAFOM, CNR IBIMET, Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Risø National Laboratory, Danish Ministry of Science, Technology and Innovation, JOINT RESEARCH CENTER EUROPEAN COMMISSION, Partenaires IRSTEA, and Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
Subjects: 010504 meteorology & atmospheric sciences, Eddy covariance, Climate change, drought, ecosystem productivity, 01 natural sciences, FluxNet, Evapotranspiration, eddy covariance, Environmental Chemistry, Ecosystem, 0105 earth and related environmental sciences, General Environmental Science, Remote sensing, carbon balance, Global and Planetary Change, Ecology, Biosphere, 04 agricultural and veterinary sciences, 15. Life on land, ecosystem modelling, climate change, 13. Climate action, Photosynthetically active radiation, Climatology, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Environmental science, Ecosystem respiration, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract: International audience; The European CARBOEUROPE/FLUXNET monitoring sites, spatial remote sensing observations via the EOS‐MODIS sensor and ecosystem modelling provide independent and complementary views on the effect of the 2003 heatwave on the European biosphere's productivity and carbon balance. In our analysis, these data streams consistently demonstrate a strong negative anomaly of the primary productivity during the summer of 2003. FLUXNET eddy‐covariance data indicate that the drop in productivity was not primarily caused by high temperatures (‘heat stress’) but rather by limitation of water (drought stress) and that, contrary to the classical expectation about a heat wave, not only gross primary productivity but also ecosystem respiration declined by up to more than to 80gCm$^{-2}$month$^{-1}$. Anomalies of carbon and water fluxes were strongly correlated. While there are large between‐site differences in water‐use efficiency (WUE, 1–6 kg Ckg$^{−1}$H$_2$O) here defined as gross carbon uptake divided by evapotranspiration (WUE=GPP/ET), the year‐to‐year changes in WUE were small (
Published: 2007
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119. Effets de la fertilisation et de l’irrigation sur le statut P du sol et les activités phosphatases

Author: Arif Ali Muhammad, Céline Meredieu, Mark Ronald Bakker, Pierre Trichet, Jacques Guinberteau, Laurent AUGUSTO, Etienne Saur, Odile Domergue, Antoine Galiana, Yves Prin, Denis Loustau, Claude Plassard, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Biodiversité, Gènes & Communautés (BioGeCo), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB), Transfert Sol-Plante et Cycle des Eléments Minéraux dans les Ecosystèmes Cultivés (TCEM), Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Unité de recherche Mycologie et Sécurité des Aliments (MycSA), Laboratoire des symbioses tropicales et méditerranéennes (UMR LSTM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Montpellier 1 (UM1)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)
Subjects: ECTOMYCORHIZE, PHOSPHORE ORGANIQUE TOTAL, [SDV]Life Sciences [q-bio], MORPHOTYPES, [SDE]Environmental Sciences, PIN MARITIME, PHOSPHORE OLSEN, ComputingMilieux_MISCELLANEOUS
Abstract: National audience
Published: 2007

120. Impacts of climate change on temperate forests and interaction with management

Author: P. Ciais, P. H. Freer-Smith, Vincent Badeau, M. L. Desprez-Loustau, Jérôme Ogée, Florent Mouillot, A. Roques, Michel Déqué, Denis Loustau, M. S. J. Broadmeadow, Eric Dufrêne, Isabelle Chuine, Nicolas Viovy, J. M. Lynch, and J. L. Dupouey
Subjects: Agroforestry, Forest management, Biodiversity, Climate change, Biogeochemistry, Environmental science, Soil classification, Environmental impact assessment, Soil fertility, Temperate rainforest
Published: 2007
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121. The European terrestrial biosphere affected by the 2005 and 2003 climate anomalies: comparative analysis of processes and spatial patterns

Author: Markus Reichstein, Viovy, N., Philippe Ciais, Mahecha, M., Aubinet, M., Barcza, Z., Beer, C., Bernhofer, C., Alain Carrara, André Granier, Grünwald, T., Haszpra, L., Nathalie Jarosz, Kutsch, W., Richard Joffre, Denis Loustau, Nagy, Z., Ourcival, J., Papale, D., Pinter, K., Serge Rambal, Sanz, M., Zähle, S., Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Université de Liège, Department of Meteorology [Budapest], Institute of Geography and Earth Sciences [Budapest], Faculty of Sciences [Budapest], Eötvös Loránd University (ELTE)-Eötvös Loránd University (ELTE)-Faculty of Sciences [Budapest], Eötvös Loránd University (ELTE)-Eötvös Loránd University (ELTE), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Centro de Estudios Ambientales del Mediterraneo, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Hungarian Meteorological Service (OMSz), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Szent István University, Tuscia University, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Hungarian Meteorological Service (OMSZ), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Università degli studi della Tuscia [Viterbo]
Subjects: carbon and water fluxes, interannual variability, télédétection, [SDV]Life Sciences [q-bio], ecosystem modelling, écosystème, flux, remote sensing, climate extremes, [SDE]Environmental Sciences, carbone, ComputingMilieux_MISCELLANEOUS, modélisation
Abstract: International audience
Published: 2006

122. Sensitivity of water and carbon fluxes to climate changes from 1960 to 2100 in european forest ecosystems

Author: Serge Rambal, C. François, A. Granier, Eddy Moors, Denis Loustau, Alexandre Bosc, Eric Dufrêne, Hendrik Davi, G. Le Maire, Unité de Recherches Forestières Méditerranéennes (URFM), Institut National de la Recherche Agronomique (INRA), Ecologie Systématique et Evolution (ESE), Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), and Wageningen University and Research Centre (WUR)
Subjects: modeling canopy photosynthesis, Atmospheric Science, CARBON SINK, 010504 meteorology & atmospheric sciences, CLIMATE CHANGE, Eddy covariance, Carbon sequestration, 01 natural sciences, Carbon cycle, FOREST ECOSYSTEM, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, global radiation, PHENOLOGY, Alterra - Centre for Water and Climate, HETRE COMMUN, Wageningen Environmental Research, direct component, CHENE ROUGE, 0105 earth and related environmental sciences, beech forest, Hydrology, increasing co2, Global and Planetary Change, atmospheric co2, elevated co2 concentration, Primary production, Carbon sink, PIN MARITIME, Forestry, 04 agricultural and veterinary sciences, 15. Life on land, Evergreen, pine forest, CANOPY SCALE, Deciduous, 13. Climate action, 040103 agronomy & agriculture, seasonal drought, CHENE VERT, 0401 agriculture, forestry, and fisheries, Environmental science, Ecosystem respiration, Agronomy and Crop Science, temperature response, Alterra - Centrum Water en Klimaat, PINUS SYLVESTRIS
Abstract: International audience; The effects of climate changes on carbon and water fluxes are quantified using a physiologically multi-layer, process-based model containing a carbon allocation model and coupled with a soil model (CASTANEA). The model is first evaluated on four EUROFLUX sites using eddy covariance data, which provide estimates of carbon and water fluxes at the ecosystem scale. It correctly reproduces the diurnal fluxes and the seasonal pattern. Thereafter simulations were conducted on six French forest ecosystems representative of three climatic areas (oceanic, continental and Mediterranean areas) dominated by deciduous species (Fagus sylvatica, Quercus robur), coniferous species (Pinus pinaster, Pinus sylvestris) or sclerophyllous evergreen species (Quercus ilex). The model is driven by the results of a meteorological model (ARPEGE) following the B2 scenario of IPCC. From 1960 to 2100, the average temperature increases by 3.1 °C (30%) and the rainfall during summer decreases by 68 mm (−27%). For all the sites, between the two periods, the simulations predict on average a gross primary production (GPP) increase of 513 g(C) m−2 (+38%). This increase is relatively steep until 2020, followed by a slowing down of the GPP rise due to an increase of the effect of water stress. Contrary to GPP, the ecosystem respiration (Reco) raises at a constant rate (350 g(C) m−2 i.e. 31% from 1960 to 2100). The dynamics of the net ecosystem productivity (GPP minus Reco) is the consequence of the effect on both GPP and Reco and differs per site. The ecosystems always remain carbon sinks however the sink strength globally decreases for coniferous (−8%), increases for sclerophyllous evergreen (+34%) and strongly increases for deciduous forest (+67%) that largely benefits by the lengthening of the foliated period. The separately quantified effects of the main variables (temperature, length of foliated season, CO2 fertilization, drought effect), show that the magnitude of these effects depends on the species and the climatic zone.
Published: 2006
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123. The CarboEurope regional experiment strategy

Author: Bruno Piguet, Vincenzo Magliulo, G. Facon, Bruno Neininger, L. F. Tolk, R. Ronda, R. Macatangay, María José Sanz, S. Körner, Eric Lamaud, Denis Loustau, A. J. Dolman, Yves Brunet, Michel Ramonet, C. Sarrat, Philippe Ciais, Marco Esposito, Ronald Hutjes, Joël Noilhan, Jan Elbers, Aurore Brut, Pierre Béziat, Nathalie Jarosz, Y. Scholz, Patrick Durand, G. Pérez-Landa, Beniamino Gioli, A. Butet, Franco Miglietta, Eric Ceschia, P. Glademard, Christoph Gerbig, O. Schrems, VU University Amsterdam, Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'aérologie (LAERO), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Consiglio Nazionale delle Ricerche (CNR), Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), ICOS-RAMCES (ICOS-RAMCES), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), ICOS-ATC (ICOS-ATC), MetAir AG, Wageningen University and Research Centre (WUR), University of Bremen, Centro de Estudios Ambientales del Mediterraneo, University of Stuttgart, Centre National d’Etudes Spatiales, Centre d'études spatiales de la biosphère (CESBIO), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Vrije Universiteit Amsterdam [Amsterdam] (VU), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Vrije universiteit = Free university of Amsterdam [Amsterdam] (VU), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), and Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Atmospheric Science, 010504 meteorology & atmospheric sciences, atmospheric transport, [SDV]Life Sciences [q-bio], Mesoscale meteorology, Climate change, hapex-mobilhy, 01 natural sciences, scale, greenhouse gases, BOUNDARY-LAYER BUDGETS, ATMOSPHERIC TRANSPORT, HAPEX-MOBILHY, CO2, CARBON, SURFACE, MODEL, SCALE, FLUX, EXCHANGE, Alterra - Centre for Water and Climate, surface, Wageningen Environmental Research, meteorology, Physics::Atmospheric and Oceanic Physics, 0105 earth and related environmental sciences, climatic change, model, carbon, Carbon exchange, exchange, carbon dioxide, frankrijk, klimaatverandering, 04 agricultural and veterinary sciences, boundary-layer budgets, flux, kooldioxide, 13. Climate action, CARBOEUROPE, Greenhouse gas, Climatology, meteorologie, [SDE]Environmental Sciences, 040103 agronomy & agriculture, co2, 0401 agriculture, forestry, and fisheries, Environmental science, Concentration gradient, france, broeikasgassen, Alterra - Centrum Water en Klimaat
Abstract: Quantification of sources and sinks of carbon at global and regional scales requires not only a good description of the land sources and sinks of carbon, but also of the synoptic and mesoscale meteorology. An experiment was performed in Les Landes, southwest France, during May¿June 2005, to determine the variability in concentration gradients and fluxes of CO2. The CarboEurope Regional Experiment Strategy (CERES; see also http://carboregional.mediasfrance.org/index) aimed to produce aggregated estimates of the carbon balance of a region that can be meaningfully compared to those obtained from the smallest downscaled information of atmospheric measurements and continental-scale inversions. We deployed several aircraft to concentration sample the CO2 and fluxes over the whole area, while fixed stations observed the fluxes and concentrations at high accuracy. Several (mesoscale) meteorological modeling tools were used to plan the experiment and flight patterns. Results show that at regional scale the relation between profiles and fluxes is not obvious, and is strongly influenced by airmass history and mesoscale flow patterns. In particular, we show from an analysis of data for a single day that taking either the concentration at several locations as representative of local fluxes or taking the flux measurements at those sites as representative of larger regions would lead to incorrect conclusions about the distribution of sources and sinks of carbon. Joint consideration of the synoptic and regional flow, fluxes, and land surface is required for a correct interpretation. This calls for an experimental and modeling strategy that takes into account the large spatial gradients in concentrations and the variability in sources and sinks that arise from different land use types. We briefly describe how such an analysis can be performed and evaluate the usefulness of the data for planning of future networks or longer campaigns with reduced experimental efforts.
Published: 2006
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124. Impacts régionalisés : cycle du carbone, hydrologie, production forestière des forêts de plaine

Author: Denis Loustau, Alexandre Bosc, Antoine Colin, Nathalie Bréda, André Granier, Christophe François, Henrik Davi, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), Inventaire Forestier National (IFN), Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Ecologie Systématique et Evolution (ESE), and Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: National audience
Published: 2005

125. Europe-wide reduction in primary productivity caused by the heat and drought in 2003

Author: Arnaud Carrara, Petri Keronen, Jean-François Soussana, Vincent Allard, Serge Rambal, A. Granier, Pierre Friedlingstein, Frédéric Chevallier, Markus Reichstein, Andrew D. Friend, Giorgio Matteucci, Philippe Ciais, Ernst Detlef Schulze, Timo Vesala, Thomas Grünwald, Riccardo Valentini, N. de Noblet, Bernard Heinesch, Kim Pilegaard, Alexander Knohl, Giovanni Manca, Franco Miglietta, Jean-Marc Ourcival, Nicolas Viovy, María José Sanz, Gerhard Krinner, M. Aubinet, Denis Loustau, Dario Papale, Jérôme Ogée, C. Bernhofer, G. Seufert, Nina Buchmann, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ICOS-ATC (ICOS-ATC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Università degli studi della Tuscia [Viterbo], Potsdam Institute for Climate Impact Research (PIK), Modélisation des Surfaces et Interfaces Continentales (MOSAIC), Ecologie et Ecophysiologie Forestière, Institut National de la Recherche Agronomique (INRA), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Unité de recherche Agronomie de Clermont (URAC), Institute of Plant Sciences, University of Bern, Faculté des Sciences Agronomiques, Académie universitaire Wallonie-Europe, Institute of Hydrology and Meteorology [Dresden], Technische Universität Dresden = Dresden University of Technology (TU Dresden), Foundation CEAM, Modélisation INVerse pour les mesures atmosphériques et SATellitaires (SATINV), Extrèmes : Statistiques, Impacts et Régionalisation (ESTIMR), Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft, Department of Physical Sciences [Helsinki], Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Department of Environmental Science, Policy, and Management [Berkeley] (ESPM), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), CNR-ISAFOM, JRC Institute for Environment and Sustainability (IES), European Commission - Joint Research Centre [Ispra] (JRC), Istituto di Biometeorologia [Firenze] (IBIMET), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Biosystems Division [Roskilde], Risø National Laboratory for Sustainable Energy (Risø DTU), Danmarks Tekniske Universitet = Technical University of Denmark (DTU)-Danmarks Tekniske Universitet = Technical University of Denmark (DTU), CARBOEUROPE-IP (European Union), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Department of Forest Environment and Resources (DISAFRI), University of Tuscia, University of Helsinki, University of California [Berkeley], University of California-University of California, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Consiglio Nazionale delle Ricerche (CNR), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Technical University of Denmark [Lyngby] (DTU)-Technical University of Denmark [Lyngby] (DTU), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Écologie fonctionnelle et physique de l'environnement (EPHYSE - UR1263), Unité de recherche d'Agronomie (UA), Technische Universität Dresden (TUD), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3)
Subjects: Crops, Agricultural, Greenhouse Effect, 0106 biological sciences, Hot Temperature, Time Factors, 010504 meteorology & atmospheric sciences, PRODUCTION PRIMAIRE, Rain, Carbon sequestration, Atmospheric sciences, 01 natural sciences, Carbon cycle, Disasters, chemistry.chemical_compound, Temperate climate, Ecosystem, Greenhouse effect, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, 0105 earth and related environmental sciences, 2. Zero hunger, Multidisciplinary, Atmosphere, Ecology, Carbon Dioxide, 15. Life on land, Carbon, Europe, chemistry, Productivity (ecology), 13. Climate action, Carbon dioxide, Environmental science, Ecosystem respiration, 010606 plant biology & botany
Abstract: International audience; Future climate warming is expected to enhance plant growth in temperate ecosystems and to increase carbon sequestration. But although severe regional heatwaves may become more frequent in a changing climate their impact on terrestrial carbon cycling is unclear. Here we report measurements of ecosystem carbon dioxide fluxes, remotely sensed radiation absorbed by plants, and country-level crop yields taken during the European heatwave in 2003.We use a terrestrial biosphere simulation model to assess continental-scale changes in primary productivity during 2003, and their consequences for the net carbon balance. We estimate a 30 per cent reduction in gross primary productivity over Europe, which resulted in a strong anomalous net source of carbon dioxide (0.5 Pg Cyr21) to the atmosphere and reversed the effect of four years of net ecosystem carbon sequestration. Our results suggest that productivity reduction in eastern and western Europe can be explained by rainfall deficit and extreme summer heat, respectively. We also find that ecosystem respiration decreased together with gross primary productivity, rather than accelerating with the temperature rise. Model results, corroborated by historical records of crop yields, suggest that such a reduction in Europe's primary productivity is unprecedented during the last century. An increase in future drought events could turn temperate ecosystems into carbon sources, contributing to positive carbon-climate feedbacks already anticipated in the tropics and at high latitudes.
Published: 2005
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126. Micrometeorology and flux partitioning between forest understorey and overstorey: a synthesis based on FLUXNET data

Author: Laurent Misson, Baldocchi, D. D., Black, T. A., Yves Brunet, Dorsey, J. R., Falk, M., Goldstein, A. H., Granier, A., Mark Irvine, Nathalie Jarosz, Eric Lamaud, Law, B. E., Bernard Longdoz, Denis Loustau, Mckay, M., Paw, K. T., Vickers, D., Wilson, K. B., ProdInra, Migration, Unité de bioclimatologie, Institut National de la Recherche Agronomique (INRA), Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Unité d'écophysiologie forestière, and Écologie fonctionnelle et physique de l'environnement (EPHYSE)
Subjects: [SDE.MCG] Environmental Sciences/Global Changes, [SDE.MCG]Environmental Sciences/Global Changes
Abstract: International audience; Because most forests are multi-specific and vertically heterogeneous, understanding the functioning of such complex ecosystems remains a challenge for quantifying and modeling the fluxes of CO2 between the atmosphere and the vegetation at regional scale. In particular, there is lack of knowledge concerning flux partitioning between overstorey and understorey of forests across different climates and forest types. The main objective of this study is to compare the micrometeorology and the fluxes of CO2, water and sensible heat measured by the eddy-covariance method above and below the main canopy of different forests. The eight study sites are part of the Fluxnet network, and range through various climates and structural types. Across these different biomes, the leaf area index (LAI) of the overstorey is the main factor influencing flux footprint and turbulent mixing below the canopy, and flux partitioning between overstorey and understorey. Wind direction and rates of turbulent mixing generally differ between the two levels for close canopies and low wind speed in the boundary layer. Forcing of understorey turbulent mixing by overstorey conditions is stronger in case of low overstorey LAI, while trunk space flow tends to decouple from that in the boundary layer in closed canopies. Vertical light extinction is positively correlated with overstorey LAI. During the day, efflux of CO2 from the understorey is positively related to soil temperature. Uptake of CO2 by the understorey only occurs if a significant amount of light penetrates through the overstorey and reaches a significant amount of understorey leaf area. During the night, the probability that CO2 emitted from the soil reach the top of the canopy is negatively correlated with overstorey LAI. These results will help developing sound ecosystem modeling schemes for quantifying carbon budgets at regional scales, taking into account the wide variety of mixed and vertically complex forest canopies.
Published: 2005

127. On the separation of net ecosystem exchange into assimilation and ecosystem respiration: review and improved algorithm

Author: Katka Havránková, Thomas Grünwald, Timo Vesala, Annalea Lohila, Alexander Knohl, Marc Aubinet, Franco Miglietta, Nina Buchmann, A. Granier, Denis Loustau, Eva Falge, Tilden P. Meyers, Francesco Primo Vaccari, Dennis D. Baldocchi, Jukka Pumpanen, Eyal Rotenberg, Tuomas Laurila, Hannu Ilvesniemi, María José Sanz, Dalibor Janouš, John Tenhunen, Christian Bernhofer, Dario Papale, Tagir G. Gilmanov, Jean-Marc Ourcival, Giorgio Matteucci, Dan Yakir, Riccardo Valentini, Paul Berbigier, Serge Rambal, G. Seufert, Markus Reichstein, Tuscia University, University of Bayreuth, University of California [Berkeley], University of California, Université de Liège, Unité de bioclimatologie, Institut National de la Recherche Agronomique (INRA), Technische Universität Dresden = Dresden University of Technology (TU Dresden), Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft, South Dakota State University (SDSTATE), Unité d'écophysiologie forestière, Czech Academy of Sciences [Prague] (CAS), Finnish Forest Research Institute, Finnish Meteorological Institute (FMI), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institute for Environment and Sustainability of the JRC, Partenaires INRAE, National Oceanic and Atmospheric Administration (NOAA), Consiglio Nazionale delle Ricerche (CNR), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), University of Helsinki, Weizmann Institute of Science [Rehovot, Israël], and Centro de Estudios Ambientales del Mediterraneo
Subjects: Mediterranean climate, 010504 meteorology & atmospheric sciences, ecosystem respiration, [SDE.MCG]Environmental Sciences/Global Changes, Eddy covariance, Atmospheric sciences, 01 natural sciences, computational methods, FluxNet, eddy covariance, Environmental Chemistry, Ecosystem, 0105 earth and related environmental sciences, General Environmental Science, carbon balance, Global and Planetary Change, Ecology, 04 agricultural and veterinary sciences, 15. Life on land, Evergreen forest, Deciduous, Boreal, 13. Climate action, 040103 agronomy & agriculture, temperature sensitivity of respiration, 0401 agriculture, forestry, and fisheries, Environmental science, gross carbon uptake, Ecosystem respiration
Abstract: International audience; This paper discusses the advantages and disadvantages of the different methods that separate net ecosystem exchange (NEE) into its major components, gross ecosystem carbon uptake (GEP) and ecosystem respiration (Reco). In particular, we analyse the effect of the extrapolation of night-time values of ecosystem respiration into the daytime; this is usually done with a temperature response function that is derived from long-term data sets. For this analysis, we used 16 one-year-long data sets of carbon dioxide exchange measurements from European and US-American eddy covariance networks. These sites span from the boreal to Mediterranean climates, and include deciduous and evergreen forest, scrubland and crop ecosystems. We show that the temperature sensitivity of Reco, derived from long-term (annual) data sets, does not reflect the short-term temperature sensitivity that is effective when extrapolating from night- to daytime. Specifically, in summer active ecosystems the long-term temperature sensitivity exceeds the short-term sensitivity. Thus, in those ecosystems, the application of a long-term temperature sensitivity to the extrapolation of respiration from night to day leads to a systematic overestimation of ecosystem respiration from halfhourly to annual time-scales, which can reach 425% for an annual budget and which consequently affects estimates of GEP. Conversely, in summer passive (Mediterranean) ecosystems, the long-term temperature sensitivity is lower than the short-term temperature sensitivity resulting in underestimation of annual sums of respiration. We introduce a new generic algorithm that derives a short-term temperature sensitivity of Reco from eddy covariance data that applies this to the extrapolation from night- to daytime, and that further performs a filling of data gaps that exploits both, the covariance between fluxes and meteorological drivers and the temporal structure of the fluxes. While this algorithm should give less biased estimates of GEP and Reco, we discuss the remaining biases and recommend that eddy covariance measurements are still backed by ancillary flux measurements that can reduce the uncertainties inherent in the eddy covariance data.
Published: 2005
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128. Carbon balance of coniferous forests growing in contrasting climates: model-based analysis

Author: Paul Berbigier, Denis Loustau, Belinda E. Medlyn, Achim Grelle, Lisa Wingate, Paul G. Jarvis, Bjarni D. Sigurdsson, Sune Linder, Ross E. McMurtrie, Robert Clement, University of New South Wales [Sydney] (UNSW), Unité de bioclimatologie, Institut National de la Recherche Agronomique (INRA), School of GeoSciences, University of Edinburgh, Swedish University of Agricultural Sciences (SLU), Écologie fonctionnelle et physique de l'environnement (EPHYSE), Southern Swedish Forest Research Centre, and Forest Service
Subjects: 0106 biological sciences, Atmospheric Science, 010504 meteorology & atmospheric sciences, net ecosystem exchange, [SDE.MCG]Environmental Sciences/Global Changes, Eddy covariance, eddy correlation, 01 natural sciences, soil, Soil respiration, modelling, Forest ecology, Ecosystem, Leaf area index, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Global and Planetary Change, Biomass (ecology), Ecology, bilan carbone, Forestry, 15. Life on land, forest ecosystem, 13. Climate action, Photosynthetically active radiation, Environmental science, Ecosystem respiration, Agronomy and Crop Science, respiration, 010606 plant biology & botany
Abstract: Forest carbon exchange contributes significantly to the global carbon balance and is therefore being monitored around the world, most notably using eddy covariance technology. In order to extrapolate from these measurements, we need to understand why carbon balance (or net ecosystem production, NEP) differs among forests. Here, we use a detailed model of forest carbon exchange applied to three coniferous European forests with differing NEP to pinpoint reasons for the differences among these sites. The model was parameterised using extensive ecophysiological data obtained at each site. These data gave evidence of major differences among sites in climate, leaf physiology, respiring biomass, leaf area index, and soil and biomass respiration rates. The model was compared with eddy covariance data and found to satisfactorily simulate carbon exchange by each forest. Simulations were then run which interchanged canopy structure, physiology and meteorology among sites, allowing us to quantify the contribution of each factor to the inter-site differences in gross primary productivity (GPP), ecosystem respiration (RE) and NEP. The most important factor was the difference in respiration rates, particularly soil respiration rates, among sites. Climate was also very important, with differences in incident photosynthetically active radiation (PAR) affecting GPP and differences in temperature affecting both GPP and RE. Effects of leaf area index, respiring biomass and leaf physiology on NEP were secondary, but still substantial. The work provides detailed quantitative evidence of the major factors causing differences in NEP among coniferous forests.
Published: 2005
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129. Variation of the photosynthetic capacity across a chronosequence of maritime pine correlates with needle phosphorus concentration

Author: Denis Loustau, Lisa Cantet, Alexandre Bosc, Sylvain Delzon, Écologie fonctionnelle et physique de l'environnement (EPHYSE), Institut National de la Recherche Agronomique (INRA), and Revues Inra, Import
Subjects: 0106 biological sciences, feuille, Phosphorus concentration, nutrient limitation---Pinus pinaster Ait, Chronosequence, Pinus pinaster Ait, DECLIN DE PRODUCTIVITE, 010603 evolutionary biology, 01 natural sciences, NPP DECLINE, VITESSE MAXIMALE DE CARBOXYLATION, MAXIMUM CARBOXYLATION RATE, NUTRIENT LIMITATION, PIN MARITIME, landes, maximum carboxylation rate, déclin de productivité, teneur en phosphore, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Botany, forest aging, aquitaine, photosynthèse, vitesse maximale de carboxylation, pinus pinaster, Ecology, Chemistry, Forestry, vieillissement, 15. Life on land, phosphore, NPP decline, [SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, france, 010606 plant biology & botany
Abstract: Changes in needle photosynthetic capacity has been studied across a chronosequence of four maritime pine stands aged 10-, 32-, 54- and 91-yr. We determined photosynthetic parameters from response curves of assimilation rate to air CO2 concentration (A-Ci) and radiation (A-Q) using gas exchange measurements on branches in the laboratory. Our data showed no shift in photosynthetic parameters (Vcmax, Jmax, a and Rd) with increasing stand age. This result means that the decline in productivity observed throughout our maritime pine chronosequence cannot be explained by a decrease in photosynthetic capacity but by a decline in stomatal conductance evidenced in a previous paper [7]. However, Vcmax was higher in the 32-yr-old stand compared to the other stands and theses between-stand differences were explained by leaf phosphorus concentration. Moreover, additional data of Vcmax suggest that the photosynthetic capacity may be higher at younger stages due to initial fertilisation. Therefore the P nutrition may contribute to productivity decline over the duration of the management cycle., Les variations de la capacité de la photosynthèse des aiguilles de pin maritime dans une chronoséquence sont corrélées à celles des teneurs en phosphore. Nous avons étudié l'évolution des capacités photosynthétiques foliaires dans une chronoséquence constituée de quatre peuplements équiennes de Pin maritime âgés de 10, 32, 54 et 91 ans. Les paramètres photosynthétiques ont été estimés sur des courbes de réponse du taux d'assimilation à la concentration en CO2 (A-Ci) et à la lumière (A-Q) obtenues à partir de mesures d'échange gazeux foliaire. Dans la chronoséquence étudiée, aucune tendance n'a été mise en évidence entre les paramètres photosynthétiques (Vcmax, Jmax, a et Rd) et l'âge du peuplement. Ce résultat démontre que le déclin de productivité foliaire observée dans la chronoséquence ne peut être expliqué par les capacités photosynthétiques, mais bien par une diminution de la conductance stomatique mise en évidence dans un précédent article [7]. Toutefois, des valeurs de Vcmax plus élevées ont été observées dans le peuplement de 32 ans. Ces variations de capacités photosynthétiques entre peuplements sont bien expliquées par la teneur foliaire en phosphore. L'ajout de données antérieures suggère cependant des taux supérieurs de capacités photosynthétiques chez les jeunes peuplements sans doute en lien avec une fertilisation lors de la plantation. La nutrition en phosphore pourrait ainsi contribuer au déclin de productivité dans le contexte sylvicole des Landes de Gascogne.
Published: 2005
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130. Agrometeorological research and applications needed to prepare agriculture and forestry to 21st century climate change

Author: Denis Loustau, Bernard Seguin, Eric Malézieux, Michel Déqué, Victorine Pérarnaud, Météo France, Agroclim (AGROCLIM), Institut National de la Recherche Agronomique (INRA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS), and Unité de recherches forestières (BORDX PIERR UR )
Subjects: Atmospheric Science, Modèle, 010504 meteorology & atmospheric sciences, P40 - Météorologie et climatologie, Télédétection, [SDV]Life Sciences [q-bio], F08 - Systèmes et modes de culture, Vulnerability, Climate change, 01 natural sciences, Ressource agricole, Forest ecology, Adaptation, Météorologie, 0105 earth and related environmental sciences, 2. Zero hunger, Changement climatique, Global and Planetary Change, business.industry, Regionalisation, Foresterie, Forestry, Agriculture, 04 agricultural and veterinary sciences, 15. Life on land, Donnée météorologique, continuum sol plante atmosphère, 13. Climate action, Agroécosystème, Greenhouse gas, [SDE]Environmental Sciences, 040103 agronomy & agriculture, agrométéorologie, 0401 agriculture, forestry, and fisheries, Environmental science, Crop simulation model, business, Downscaling
Abstract: International audience; The adaptation of agriculture and forestry to the climate of the twenty-first century supposes that research projects will be conducted cooperatively between meteorologists, agronomists, soil scientists, hydrologists, and modellers. To prepare for it, it is appropriate first of all to study the variations in the climate of the past using extensive, homogenised series of meteorological or phenological data. General circulation models constitute the basic tool in order to predict future changes in climate. They will be improved, and the regionalisation techniques used for downscaling climate predictions will also be made more efficient. Crop simulation models using input data from the general circulation models applied at the regional level ought to be the favoured tools to allow the extrapolation of the major trends on yield, consumption of water, fertilisers, pesticides, the environment and rural development. For this, they have to be validated according to the available agronomical data, particularly the available phenological series on cultivated crops. In addition, climate change would have impact on crop diseases and parasites, as well as on weeds. Very few studies have been carried out in this field. It is also necessary to quantify in a more accurate way the stocks and fluxes of carbon in large forest ecosystems, simulate their future, and assess the vulnerability of the various forest species to a change in climate. This is all the more important in that some propagate species choices must be made in the course of the next ten years in plantations which will experience changed climate. More broadly speaking, we shall have not only to try hard to research new agricultural and forestry practices which will reduce greenhouse gas emissions or promote the storage of carbon, but it will also be indispensable to prepare the adaptation of numerous rural communities for the climate change (with special reference to least developed countries in tropical areas, where malnutrition is a common threat). This can be accomplished with a series of new environmental management practices suited to the new climatic order.
Published: 2005
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131. Hydraulic responses to height growth in maritime pine trees

Author: Roderick C. Dewar, Denis Loustau, M. Sartore, Sylvain Delzon, Régis Burlett, Écologie fonctionnelle et physique de l'environnement (EPHYSE), and Institut National de la Recherche Agronomique (INRA)
Subjects: 0106 biological sciences, STOMATAL REGULATION, Stomatal conductance, Physiology, Chronosequence, Plant Science, 010603 evolutionary biology, 01 natural sciences, WATER POTENTIAL, Water balance, HYDRAULIC CONDUCTANCE, Botany, Potential gradient, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, biology, Xylem, Conductance, PIN MARITIME, 15. Life on land, biology.organism_classification, Agronomy, Productivity (ecology), Environmental science, Pinus pinaster, TREE HEIGHT, 010606 plant biology & botany
Abstract: International audience; As trees grow taller, decreased xylem path conductance imposes a major constraint on plant water and carbon balance, and is thus a key factor underlying forest productivity decline with age. The responses of stomatal conductance, leaf area: sapwood area ratio (A(L) : A(S)) and soil-leaf water potential gradient (DeltaPsi(S-L)) to height growth were investigated in maritime pine trees. Extensive measurements of in situ sap flow, stomatal conductance and (non-gravitational) needle water potential ((&UPsi;) over tilde (L) = Psi(L) - rho(w)gh) were made during 2 years in a chronosequence of four even-aged stands, under both wet and dry soil conditions. Under wet soil conditions, (&UPsi;) over tilde (L) was systematically lower in taller trees on account of differences in gravitational potential. In contrast, under dry soil conditions, our measurements clearly showed that (&UPsi;) over tilde (L) was maintained above a minimum threshold value of -2.0 MPa independently of tree height, thus limiting the range of compensatory change in DeltaPsi(S-L). Although a decrease in the A(L) : A(S) ratio occurred with tree height, this compensation was not sufficient to prevent a decline in leaf-specific hydraulic conductance, K-L (50% lower in 30 m trees than in 10 m trees). An associated decline in stomatal conductance with tree height thus occurred to maintain a balance between water supply and demand. Both the increased investment in non-productive versus productive tissues (A(S) : A(L)) and stomatal closure may have contributed to the observed decrease in tree growth efficiency with increasing tree height (by a factor of three from smallest to tallest trees), although other growth-limiting responses (e.g. soil nutrient sequestration, increased respiratory costs) cannot be excluded
Published: 2004
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132. Modelling as a forest management decision tool in response to climate change regional impacts of climate change on wood production and carbon storage in temperate forests

Author: Denis Loustau, Alexandre Bosc, Colin, A., Jérôme Ogée, Michel Déqué, Cloppet, E., Dominique Arrouays, Christine Le Bas, Nicolas Saby, Pignard, J., Nawel Hamza, François, C., Dufrene, E., Hendrik Davi, Soudani, K., Viovy, N., Philippe Ciais, André Granier, Nathalie Breda, Vincent Badeau, Jean-Luc Dupouey, Marie Laure Desprez Loustau, Benoit Marçais, Cécile Robin, Richard Joffre, ProdInra, Migration, Unité de bioclimatologie, Institut National de la Recherche Agronomique (INRA), InfoSol (InfoSol), Unité de recherche Science du Sol (USS), Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Unité Mixte de Recherche en Santé Végétale (INRA/ENITA) (UMRSV), Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut des Sciences de la Vigne et du Vin (ISVV), and Unité de recherche pathologie forestière
Subjects: [SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, HETRE, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, BILAN CARBONE, PIN MARITIME, ComputingMilieux_MISCELLANEOUS, CHENE
Abstract: National audience
Published: 2004

133. Transpiration et conductance stomatique du pin maritime en situation de contrainte hydrique

Author: Denis Loustau, Domaine Expérimental de l'Hermitage (PIERROTON UE), Institut National de la Recherche Agronomique (INRA), AIP 'Protection et valorisation des ressources en eau', INRA, Contrat : Compte rendu du projet, and Superviseur : Denis Loustau
Subjects: [SDV]Life Sciences [q-bio]
Published: 1993

134. Economie de l'eau au niveau sol, arbres et peuplements dans des écosystèmes forestiers de basse altitude. Incidence sur la croissance et l'état de santé des peuplements

Author: Denis Loustau, Domaine Expérimental de l'Hermitage (PIERROTON UE), Institut National de la Recherche Agronomique (INRA), MRE, INRA, and Superviseur : Denis Loustau
Subjects: [SDV]Life Sciences [q-bio]
Published: 1993

135. Variability of stem and branch maintenance respiration in a Pinus pinaster tree

Author: Denis Loustau, Alexandre Bosc, Agnès de Grandcourt, Unité de recherches forestières (BORDX PIERR UR ), Institut National de la Recherche Agronomique (INRA), Ecologie des forêts de Guyane (ECOFOG), Ecole Nationale du Génie Rural, des Eaux et des Forêts (ENGREF)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-Centre National de la Recherche Scientifique (CNRS), ProdInra, Archive Ouverte, and Unité de Recherches Forestières
Subjects: 0106 biological sciences, Maintenance respiration, Plant Stems, Physiology, Cell Respiration, Q10, PIN MARITIME, Plant Science, Biology, biology.organism_classification, Pinus, 010603 evolutionary biology, 01 natural sciences, Trees, Horticulture, Dry weight, ANALYSE, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Botany, Pinus pinaster, Tree (set theory), Phloem, [SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Temperature response, 010606 plant biology & botany
Abstract: The relationship between maintenance respiration (Rm) of woody organs and their structural characteristics was explored in adult Pinus pinaster Ait. trees. We measured Rm on 75 stem and branch segments of different ages (from 3 to 24 years) and diameters (from 1 to 35 cm). The temperature response of Rm was derived from field measurements based on a classical exponential function with Q10 = 2.13. Relationships between Rm and the dimensions of the woody organs were analyzed under controlled conditions in the laboratory. The surface area of a woody organ was a better predictor of Rm than volume, but surface area failed to account for the observed within-tree variability of Rm among stems, branches and twigs. Two simple models were proposed to predict the variability of Rm at 15 degrees C in an adult tree. Model 1, a linear function model based on the dry mass and nitrogen concentration of sapwood and phloem tissues, explained most of the variability of Rm in branches and stems (R2 = 0.97). We concluded that the respective contributions of the phloem and sapwood depend on the location and diameter of the woody organ. Model 2, a power-law function model based on the length, diameter and age of the sample, explained the same variance of Rm as Model 1 and is appropriate for scaling Rm to the stand level. Models 1 and 2 appear to explain a larger variability of Rm than models based on stem area or sapwood mass.
Published: 2003

136. Effets de la co-limitation en phosphore et en carbone sur la croissance et la morphologie du pin maritime (Pinus pinaster Aït.)

Author: Alissar Cheaïb, Alain Mollier, Sylvain Pellerin, Stéphane Thunot, Catherine Lambrot, Denis Loustau, ProdInra, Migration, Institut National de la Recherche Agronomique (INRA), Unité d'agronomie, and Unité de recherches forestières (BORDX PIERR UR )
Subjects: [SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: National audience
Published: 2003

137. Clear-cutting effects on soil organic matter content and quality in a temperate maritime pine forest a spatial and temporal assessment

Author: Claudy Jolivet, Dominique Arrouays, Bourhis, F., Hocine Bourennane, Andreux, F., Leveque, J., Richer-De-Forges, Anne C., Rémi Chaussod, Denis Loustau, Pierre Trichet, Didier Bert, Angers, D., Chantigny, M., Chadoeuf, Joel J., Henri Ciesielski, ProdInra, Migration, Unité de recherche Science du Sol (USS), Institut National de la Recherche Agronomique (INRA), Microbiologie, Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), Unité de recherches forestières (BORDX PIERR UR ), Biostatistique et Processus Spatiaux (BioSP), and Laboratoire d'Analyses des Sols (LAS)
Subjects: [SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, ECHANTILLONAGE, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, VARIABILITE SPATIO-TEMPORELLE, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2002

138. Seasonal and interannual variations in carbon isotope discrimination in a maritime pine (Pinus pinaster) stand assessed from the isotopic composition of cellulose in annual rings

Author: Denis Loustau, Annabel J. Porté, ProdInra, Migration, Unité de Recherches Forestières Méditerranéennes (URFM), Institut National de la Recherche Agronomique (INRA), and Unité de recherches forestières (BORDX PIERR UR )
Subjects: 0106 biological sciences, Delta, 010504 meteorology & atmospheric sciences, Physiology, Vapour Pressure Deficit, chemistry.chemical_element, Plant Science, Atmospheric sciences, 01 natural sciences, Trees, Water balance, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, VARIABILITE INTERARBRE, Dendrochronology, Cellulose, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Carbon Isotopes, biology, Plant Stems, Ecology, PIN MARITIME, Water, 15. Life on land, biology.organism_classification, Pinus, DEFICIT DE VAPEUR D'EAU, chemistry, Isotopes of carbon, Soil water, Environmental science, Pinus pinaster, France, Seasons, [SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Carbon, TENEUR EN EAU DU SOL, 010606 plant biology & botany
Abstract: Stable carbon isotope composition (delta; per thousand) was measured on cellulose extracted from maritime pine (Pinus pinaster Ait.) tree rings to investigate inter-tree and interannual variability (7 trees, 20 rings per tree, each ring divided into early and late wood). A model of stand primary production coupled to water balance was used to calculate the stand annual water-use efficiency (WUE). Inter-tree variability in discrimination (maximum 2.88 per thousand in late wood in 1989, 2.69 per thousand in early wood in 1983) was as large as interannual variation (maximum 2.72 per thousand in late wood, 2.05 per thousand in early wood). Tree size did not explain these differences. Relationships were found between annual discrimination and climate variables such as annual rainfall, summer temperature and vapor pressure deficit (VPD). Higher correlations were found with late wood discrimination. Early wood discrimination was shown to be related to previous-year late wood discrimination. Late wood discrimination was also related to soil water availability. Stand annual WUE was only weakly related to tree ring carbon discrimination.
Published: 2001

139. Effects of variable root damage caused by Phytophthora cinnamomi on water relations of chestnut saplings

Author: Marion Maurel, Denis Loustau, Cécile Robin, Marie-Laure Desprez-Loustau, Xavier Capdevielle, Unité Mixte de Recherche en Santé Végétale (INRA/ENITA) (UMRSV), Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut des Sciences de la Vigne et du Vin (ISVV), Unité de recherches forestières (BORDX PIERR UR ), and Institut National de la Recherche Agronomique (INRA)
Subjects: 0106 biological sciences, Stomatal conductance, arbre forestier, [SDV]Life Sciences [q-bio], split-root, potentiel hydrique foliaire, MYCOLOGIE, Phytophthora cinnamomi, 010603 evolutionary biology, 01 natural sciences, leaf water potential, phytophthora cinnamomi, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, castanea sativa, Botany, conductance stomatique, Phycomycetes, Water content, water stress---Castanea sativa, castanea, ComputingMilieux_MISCELLANEOUS, Transpiration, châtaignier, 2. Zero hunger, Ecology, biology, Inoculation, food and beverages, Forestry, 15. Life on land, biology.organism_classification, 6. Clean water, maladie des plantes, Fagaceae, racine, Horticulture, stomatal conductance, Phytophthora, stress hydrique, 010606 plant biology & botany
Abstract: International audience; The effects of Phytophthora cinnamomi root damage on water relations of chestnut (Castanea sativa) saplings were investigated. The relationship between root damage severity and impact on water relations was studied using a four compartment split-root system. Saplings were submitted to five inoculation levels and two watering conditions: normal (well-watered) or restricted watering. In well-watered saplings, stomatal conductance and whole plant transpiration rate were negatively correlated to the proportion of necrotic roots. Nevertheless, plant hydraulic conductance and leaf water potential were only affected above 90% necrotic roots. Interaction between root damage and water restriction was difficult to assess, since soil moisture decreased only slightly in infested compartments. However, saplings under restricted watering displayed lower stomatal conductance and transpiration values, regardless of root damage severity. Furthermore, the threshold of root damage leading to a decrease in leaf water potential was lower under restricted watering than under normal watering.; Effets de dégâts racinaires variables causés par Phytophthora cinnamomi sur le fonctionnement hydrique de jeunes châtaigniers. Les effets des dégâts racinaires causés par Phytophthora cinnamomi sur le fonctionnement hydrique de jeunes châtaigniers (Castanea sativa) ont été étudiés. Afin de relier les effets observés à la sévérité des dégâts racinaires, un système de "split-root " à quatre compartiments a été utilisé. Les arbres ont été soumis à cinq niveaux d'inoculation et à deux régimes hydriques (arrosage normal ou arrosage réduit). Chez les arbres normalement arrosés, une diminution linéaire de la conductance stomatique et de la transpiration avec la proportion de racines nécrosées a été observée. Cependant, la conductance hydraulique de l'arbre et le potentiel hydrique foliaire n'ont été affectés qu'à partir de 90 % de racines nécrosées. L'interaction entre les dégâts racinaires et la restriction en eau a été difficile à évaluer car l'humidité du sol a faiblement baissé dans les compartiments inoculés. Cependant, les arbres soumis a une restriction en eau avaient une conductance stomatique et une transpiration faibles quelle que soit la proportion de racines nécrosées. De plus, le seuil de dégâts racinaires entraînant une baisse de potentiel hydrique foliaire était plus faible chez les arbres soumis à une restriction en eau que chez les arbres normalement arrosés.
Published: 2001
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140. Silvicultural factors influencing windthrow in maritime pine stands

Author: Jean-Michel Carnus, Didier Bert, Véronique Cucchi, Pierre Trichet, Denis Loustau, Unité de recherches forestières (BORDX PIERR UR ), and Institut National de la Recherche Agronomique (INRA)
Subjects: arbre forestier, densité, pinus pinaster, [SDV]Life Sciences [q-bio], PIN MARITIME, ZONE DE CHABLIS, plantation, sylviculture, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2001

141. Estimating the foliage area of Maritime pine (Pinus pinaster Aït.) branches and crowns with application to modelling the foliage area distribution in the crown

Author: Annabel J. Porté, Alexandre Bosc, Denis Loustau, and I. Champion
Subjects: 0106 biological sciences, allometric relationship---pin maritime, 010504 meteorology & atmospheric sciences, Ecology, biology, Crown (botany), Forestry, 15. Life on land, maritime pine, biology.organism_classification, surface foliaire, 01 natural sciences, foliage distribution, Geography, foliage area, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Botany, Pinus pinaster, distribution foliaire, relations allométriques, 010606 plant biology & botany, 0105 earth and related environmental sciences
Abstract: International audience; Destructive measurements of architecture and biomass were performed on 63 trees from three Pinus pinaster stands (5, 21 and 26 year-old) in order to determine the quantity and distribution of foliage area inside the crown. Allometric equations were developed per site and needle age, which allowed to correctly calculate ($R^2 = 0.71$ to 0.79) the foliage area of a branch, knowing its basal diameter and its relative insertion height in the crown. Using these equations, we estimated total crown foliage area. A non-linear function of tree diameter and tree age was fitted to these data ($R^2 = 0.82$ and 0.88). On the 5 and 26 year-old stands, we combined the branch level models and the architectural measurements to develop probability functions describing the vertical and horizontal foliage area distributions inside the crown. The parameters of the beta functions varied with needle and stand age, foliage being located mostly in the upper and outer part of the crown for the adult tree, whereas it was more abundant in the inner and lower parts of the crown in the 5 year-old trees. A simple representation of crown shape was added to the study, so that knowing tree age and diameter, it could be possible to fully describe the quantity of foliage area and its localisation inside a maritime pine crown.; Estimation de la surface foliaire de branches et de houppiers de Pin maritime (Pinus pinaster Aït.) et son application pour modéliser la distribution de la surface foliaire dans le houppier. Afin de déterminer la quantité et la distribution de la surface foliaire dans un houppier de pin maritime, nous avons réalisé une analyse destructive de l'architecture et de la biomasse de 63 arbres issus de trois peuplements âgés de 5, 21 et 26 ans. Des équations allométriques par peuplement et année foliaire permettent de calculer correctement ($R^2 = 0,71$ à 0,79) la surface foliaire d'une branche connaissant son diamètre et sa hauteur relative d'insertion. L'utilisation de ces équations a permis d'estimer la surface foliaire totale du houppier. Un modèle arbre correspondant à une fonction puissance du diamètre de l'arbre et de l'inverse de son âge a été ajusté sur ces valeurs ($R^2 = 0,80$ et 0,88). D'autre part, la combinaison des modèles branches et des mesures architecturales a permis de paramétrer des fonctions de type bêta, sur les sites de 5 et 26 ans, décrivant les distributions verticales et horizontales de la surface foliaire dans le houppier. Leurs paramètres variaient avec l'âge du site et de la cohorte : le feuillage étant localisé dans la partie supérieure et extérieure du houppier chez les arbres adultes, et davantage vers le bas et l'intérieur de la couronne des arbres de 5 ans. Une représentation simplifiée de la forme du houppier a été ajoutée à l'établissement des profils de surface foliaire afin que la connaissance de l'âge et du diamètre à 1,30 m d'un pin maritime suffisent à établir une description quantitative et qualitative de son feuillage.
Published: 2000
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142. Respiration as the main determinant of carbon balance in European forests

Author: Leonardo Montagnani, Anders Lindroth, Eddy Moors, John Moncrieff, A. Granier, K. Morgenstern, Marc Aubinet, A. Ibrom, N.O. Jensen, Denis Loustau, Kim Pilegaard, Christian Bernhofer, Üllar Rannik, Achim Grelle, Paul G. Jarvis, A. J. Dolman, H. Thorgeirsson, Andrew S. Kowalski, Giorgio Matteucci, Robert Clement, Jón Guðmundsson, Riccardo Valentini, Patrick Gross, Thomas Grünwald, Paul Berbigier, Ernst Detlef Schulze, Timo Vesala, Reinhart Ceulemans, Corinna Rebmann, and Stefano Minerbi
Subjects: Multidisciplinary, 010504 meteorology & atmospheric sciences, Ecology, Carbon sink, Biosphere, Primary production, 04 agricultural and veterinary sciences, 15. Life on land, Carbon sequestration, Atmospheric sciences, 01 natural sciences, Carbon cycle, 13. Climate action, Forest ecology, 040103 agronomy & agriculture, Life Science, 0401 agriculture, forestry, and fisheries, Environmental science, Ecosystem, Wageningen Environmental Research, Ecosystem respiration, 0105 earth and related environmental sciences
Abstract: Carbon exchange between the terrestrial biosphere and the atmosphere is one of the key processes that need to be assessed in the context of the Kyoto Protocol1. Several studies suggest that the terrestrial biosphere is gaining carbon2,3,4,5,6,7,8, but these estimates are obtained primarily by indirect methods, and the factors that control terrestrial carbon exchange, its magnitude and primary locations, are under debate. Here we present data of net ecosystem carbon exchange, collected between 1996 and 1998 from 15 European forests, which confirm that many European forest ecosystems act as carbon sinks. The annual carbon balances range from an uptake of 6.6 tonnes of carbon per hectare per year to a release of nearly 1 t C ha-1 yr-1, with a large variability between forests. The data show a significant increase of carbon uptake with decreasing latitude, whereas the gross primary production seems to be largely independent of latitude. Our observations indicate that, in general, ecosystem respiration determines net ecosystem carbon exchange. Also, for an accurate assessment of the carbon balance in a particular forest ecosystem, remote sensing of the normalized difference vegetation index or estimates based on forest inventories may not be sufficient.
Published: 2000

143. Carbon stocks estimates for french forests

Author: Pignard, G., Dupouey, J. -L, Arrouays, D., Denis Loustau, Unité d'écophysiologie forestière, Institut National de la Recherche Agronomique (INRA), Unité de recherche Science du Sol (USS), and Unité de recherches forestières (BORDX PIERR UR )
Subjects: sciences du sol, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, estimation, forêt, technique analytique, biomasse, TENEUR DANS LE SOL, Biotechnologies, carbone, france, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2000

144. Magnani et al. reply

Author: Anders Lindroth, Vanessa Tedeschi, John Moncrieff, Pasi Kolari, Maurizio Mencuccini, Harry Lankreijer, Beverly E. Law, Giovanni Manca, Pertti Hari, Frank Berninger, Sylvain Delzon, Andrew S. Kowalski, John Grace, Paul G. Jarvis, Marco Borghetti, Denis Loustau, Riccardo Valentini, Achim Grelle, and Federico Magnani
Subjects: 0106 biological sciences, Nitrogen deposition, Multidisciplinary, 010504 meteorology & atmospheric sciences, Ecology, Biodiversity, Interspecific competition, 15. Life on land, 010603 evolutionary biology, 01 natural sciences, chemistry.chemical_compound, Forest dieback, Nitrate, chemistry, 13. Climate action, Sustained response, Environmental science, Ecosystem, Saturation (chemistry), 0105 earth and related environmental sciences
Abstract: Replying to: A. De Schrijver et al. , 10.1038/nature06578 ; W. de Vries et al. , 10.1038/nature06579 (2008) Nitrogen (N) deposition alters ecosystem function in several ways, with important effects on N leaching and water quality, as well as on interspecific competition and biodiversity. These changes have been attributed to ecosystem N saturation, defined as the alleviation of N limitations on rates of biological function1. After an initial fertilization effect, N saturation has also been suggested to reduce plant function and growth2, eventually leading to forest dieback. Although our observation of a substantial positive effect of N deposition on forest carbon (C) sequestration3 does not imply the absence of nitrate losses or other negative effects, as rightly stressed by De Schrijver 4, the sustained response observed demonstrates that the fear of a generalized forest decline in response to N fertilization could be overstated, at least within the rather broad N deposition range explored in our analysis. The nature of the observed response of forest C sequestration to N deposition, however, has been questioned outright by de Vries 5, who suggested that it could be an artefact resulting from the covariation between N deposition and other environmental variables. The arguments proposed against an overwhelming N effect, however, do not seem to stand up to close scrutiny.
Published: 2008
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145. Fonctionnement primaire et productivité de la forêt landaise : implications pour une gestion durable

Author: Pierre Trichet, Denis Loustau, Didier Bert, Unité de recherches forestières (BORDX PIERR UR ), Institut National de la Recherche Agronomique (INRA), and ProdInra, Migration
Subjects: 0106 biological sciences, Spermatophyta, Ecosystème, Pinus pinaster, Review, Forests, 01 natural sciences, Sustainable forestry, Softwood forest tree, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Regional study, Peuplement forestier, Silviculture, ComputingMilieux_MISCELLANEOUS, Hydrologie, Forest stand, biology, Forest management, Bioclimatology, Aquitaine, Foresterie, Forestry, 04 agricultural and veterinary sciences, Biogeochemistry, Europe, Forêt, Arbre forestier résineux, [SDE]Environmental Sciences, France, [SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Bioclimatologie, Biogéochimie, Sylviculture, Production forestière, sustainable forestry -- Coniferales, Foresterie durable -- Coniferales, Hydrology (agriculture), Forest production, Gestion forestière, Ecosystem, Article synthèse, Productivité primaire, biology.organism_classification, Etude régionale, Landes de Gascogne, 040103 agronomy & agriculture, Primary productivity, 0401 agriculture, forestry, and fisheries, Environmental science, Hydrology, Gymnospermae, 010606 plant biology & botany
Abstract: International audience
Published: 1999
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146. Photosynthetic responses to phosphorus nutrition in two-year-old maritime pine seedlings

Author: Mohamed Ben Brahim, Jean-Pierre Gaudillère, Denis Loustau, Erwin Dreyer, Unité de recherches forestières (BORDX PIERR UR ), Institut National de la Recherche Agronomique (INRA), Unité d'agronomie, Unité d'écophysiologie forestière, and ProdInra, Migration
Subjects: 0106 biological sciences, Stomatal conductance, Physiology, Irradiance, Plant Science, Photosynthesis, 01 natural sciences, 03 medical and health sciences, chemistry.chemical_compound, Animal science, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Botany, Chlorophyll fluorescence, ComputingMilieux_MISCELLANEOUS, 030304 developmental biology, 0303 health sciences, biology, RuBisCO, PIN MARITIME, Phosphate, biology.organism_classification, Carboxylation, chemistry, biology.protein, Pinus pinaster, [SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, 010606 plant biology & botany
Abstract: We analyzed processes limiting photosynthesis in two-year-old, container-grown Pinus pinaster Ait. seedlings subjected to phosphorus (P) deficiency. After withholding P for 3 months, seedlings were supplied P at four relative addition rates (0, 0.005, 0.01 and 0.02 day(-1)) in a nutrient recycling system. At Weeks 12 and 22, responses of photosynthesis to CO(2) and irradiance were measured and the following parameters derived: maximal velocity of carboxylation by Rubisco, V(m); apparent quantum efficiency of electron transport, alpha maximal electron transport rate, J(m); stomatal conductance and relative stomatal limitation of photosynthesis. At Week 22, these measurements were combined with concurrent measurements of chlorophyll fluorescence to determine the quantum yield of PSII, and a theoretical partitioning of total light-driven linear electron flow between fractions used to regenerate carboxylated and oxygenated RuBP. After 12 weeks of treatment, needle P concentrations ranged from 0.04 to 0.15 x 10(-2) g g(DW) (-1), and then remained constant until Week 22. Values of J(m), alpha and V(m) increased with increasing needle P concentration (from 30 to 133mgr;mol m(-2) s(-1), 0.02 to 0.25 mol mol(-1) and 13 to 78mgr;mol CO(2) m(-2) s(-1) at the lowest and highest needle P concentrations, respectively). Under ambient conditions, net assimilation rates in P-deficient seedlings were limited by V(m) under saturating irradiance, and by J(m) under limiting irradiance, but not by triose-P regeneration. There was no detectable change in the partitioning of total light-driven linear electron flow between the fractions used for carboxylation and oxygenation. Predawn photochemical efficiency of PSII was significantly reduced in seedlings with low P concentrations. Although stomatal conductance tended to decrease with decreasing needle P concentration, relative stomatal limitation was not significantly affected. At Week 22, there was an attenuation of the effects of P nutrition on V(m) and an increase in alpha and J(m) that was probably related to cessation of growth and the seasonal decline in natural irradiance.
Published: 1999

147. Le maintien de la fertilité des sols forestiers landais dans le cadre de la sylviculture intensive du pin maritime. Revue bibliographique et identification des pistes de recherches

Author: Pierre Trichet, Claudy Jolivet, Dominique Arrouays, Denis Loustau, Didier Bert, Ranger, Jacques J., Unité de recherches forestières (BORDX PIERR UR ), Institut National de la Recherche Agronomique (INRA), Unité de recherche Science du Sol (USS), and Unité de recherche Biogéochimie des Ecosystèmes Forestiers (BEF)
Subjects: DISPONIBILITE D'ELEMENT NUTRITIF, PIN MARITIME, [SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study, ComputingMilieux_MISCELLANEOUS
Abstract: National audience
Published: 1999

148. Interpreting the variations in xylem sap flux density within the trunk of maritime pine (Pinus pinaster Ait.): application of a model for calculating water flows at tree and stand levels

Author: Jean-Christophe Domec, Alexandre Bosc, Denis Loustau, Revues Inra, Import, ProdInra, Migration, Unité de recherches forestières (BORDX PIERR UR ), and Institut National de la Recherche Agronomique (INRA)
Subjects: 0106 biological sciences, Physics, 010504 meteorology & atmospheric sciences, biology, PIN MARITIME, Forestry, Plant Science, biology.organism_classification, 01 natural sciences, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, Pinus pinaster, [SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, ComputingMilieux_MISCELLANEOUS, 010606 plant biology & botany, 0105 earth and related environmental sciences
Abstract: La densite de flux de seve brute d'un pin maritime de 25 ans a ete mesuree en continu a differentes positions du tronc et durant une saison de croissance complete, par une methode a flux de chaleur constant, dans le but a) d'etudier la variabilite de la densite de flux dans la section transversale du tronc et b) d'analyser le decalage de temps du signal entre differentes hauteurs au cours de la journee. Les mesures ont ete effectuees a cinq hauteurs, de 1,3 a 15 m au dessus du sol. A deux niveaux (1,3 m et sous la couronne vivante, respectivement) la densite de flux a ete mesuree suivant quatre azimuts. L'evolution journaliere de la transpiration du couvert, de la transpiration des aiguilles, du potentiel hydrique du tronc et des aiguilles et des variations de volume du tronc a aussi ete mesuree durant quatre journees couvrant une gamme de niveaux d'humidite du sol. Au niveau arbre, la variabilite de la densite de flux de seve dans la section horizontale de l'aubier etait plus elevee a la base du tronc que sous la couronne. Ceci pourrait s'expliquer par l'anisotropie des proprietes mecaniques et hydrauliques du bois dans le plan horizontal, classique chez le pin maritime, plutot que par une sectorisation du flux liee a l'architecture de la couronne. Au niveau peuplement, aucune relation entre la densite de flux de seve et le statut social de l'arbre n'a ete mise en evidence, ce qui s'explique par l'homogeneite du peuplement et son faible indice foliaire. Nous avons utilise un modele de transfert RC a trois compartiments pour interpreter les variations de flux de seve le long du transfert sol-aiguille. Les methodes de determination des resistance et capacitance de chaque compartiment sont decrites. Les sorties du modele ont ete comparees avec les mesures de transpiration, flux de seve et de potentiel hydrique mesurees dans deux peuplements âges de 25 et 65 ans respectivement. Le modele explique assez bien les variations de flux observees le long du continuum sol-aiguille. Au cours de la secheresse, on observe une augmentation importante (× 10) de la resistance du compartiment racine tronc. Cette augmentation est moins importante dans les branches (× 2). Les capacitances sont peu affectees par la secheresse.
Published: 1998

149. Le maintien de la fertilité des sols forestiers landais dans le cadre de la sylviculture intensive du pin maritime

Author: Pierre Trichet, Claudy Jolivet, Dominique Arrouays, Denis Loustau, Unité de recherches forestières (BORDX PIERR UR ), Institut National de la Recherche Agronomique (INRA), and Unité de recherche Science du Sol (USS)
Subjects: [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, PIN MARITIME, ComputingMilieux_MISCELLANEOUS
Abstract: National audience
Published: 1997

150. Architecture de peuplements forestiers et modélisation des échanges physiques et du fonctionnement

Author: Isabelle Champion, Denis Loustau, ProdInra, Migration, Unité de bioclimatologie, and Institut National de la Recherche Agronomique (INRA)
Subjects: [SDV] Life Sciences [q-bio], [SDV]Life Sciences [q-bio], PIN MARITIME, ComputingMilieux_MISCELLANEOUS
Abstract: National audience
Published: 1997

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