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Author Maréchaux, I.; Bonal, D.; Bartlett, M.K.; Burban, B.; Coste, S.; Courtois, E.A.; Dulormne, M.; Goret, J.-Y.; Mira, E.; Mirabel, A.; Sack, L.; Stahl, C.; Chave, J. url  doi
openurl 
  Title Dry-season decline in tree sapflux is correlated with leaf turgor loss point in a tropical rainforest Type Journal Article
  Year 2018 Publication Functional Ecology Abbreviated Journal (down) Funct Ecol  
  Volume 32 Issue 10 Pages 2285-2297  
  Keywords drought tolerance; hydraulic conductance; sap flow; sapflux density; tropical trees; turgor loss point; water potential; wilting point  
  Abstract Water availability is a key determinant of forest ecosystem function and tree species distributions. While droughts are increasing in frequency in many ecosystems, including in the tropics, plant responses to water supply vary with species and drought intensity and are therefore difficult to model. Based on physiological first principles, we hypothesized that trees with a lower turgor loss point (pi-tlp), that is, a more negative leaf water potential at wilting, would maintain water transport for longer into a dry season. We measured sapflux density of 22 mature trees of 10 species during a dry season in an Amazonian rainforest, quantified sapflux decline as soil water content decreased and tested its relationship to tree pi-tlp, size and leaf predawn and midday water potentials measured after the onset of the dry season. The measured trees varied strongly in the response of water use to the seasonal drought, with sapflux at the end of the dry season ranging from 37 to 117% (on average 83 +/- 5 %) of that at the beginning of the dry season. The decline of water transport as soil dried was correlated with tree pi-tlp (Spearman's rho > 0.63), but not with tree size or predawn and midday water potentials. Thus, trees with more drought-tolerant leaves better maintained water transport during the seasonal drought. Our study provides an explicit correlation between a trait, measurable at the leaf level, and whole-plant performance under drying conditions. Physiological traits such as pi-tlp can be used to assess and model higher scale processes in response to drying conditions.  
  Address  
  Corporate Author Thesis  
  Publisher Wiley/Blackwell (10.1111) Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0269-8463 ISBN Medium  
  Area Expedition Conference  
  Notes doi: 10.1111/1365-2435.13188 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 830  
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Author González, A.L.; Céréghino, R.; Dézerald, O.; Farjalla, V.F.; Leroy, C.; Richardson, B.A.; Richardson, M.J.; Romero, G.Q.; Srivastava, D.S. url  doi
openurl 
  Title Ecological mechanisms and phylogeny shape invertebrate stoichiometry: A test using detritus-based communities across Central and South America Type Journal Article
  Year 2018 Publication Functional Ecology Abbreviated Journal (down) Funct Ecol  
  Volume 32 Issue 10 Pages 2448-2463  
  Keywords body size scaling; carnivores; detritivores; ecological stoichiometry; macroinvertebrates; nitrogen; phosphorous; phylogenetic signal  
  Abstract Stoichiometric differences among organisms can affect trophic interactions and rates of nutrient cycling within ecosystems. However, we still know little about either the underlying causes of these stoichiometric differences or the consistency of these differences across large geographical extents. Here, we analyse elemental (carbon, nitrogen, phosphorus) composition of 872 aquatic macroinvertebrates (71 species) inhabiting tank bromeliads (n = 140) from five distantly located sites across Central and South America to (i) test phylogenetic, trophic and body size scaling explanations for why organisms differ in elemental composition and (ii) determine whether patterns in elemental composition are universal or context dependent. Taxonomy explained most variance in elemental composition, even though phylogenetic signals were weak and limited to regional spatial extents and to the family level. The highest elemental contents and lowest carbon:nutrient ratios were found in organisms at high trophic levels and with smaller body size, regardless of geographical location. Carnivores may have higher nutrient content and lower carbon:nutrient ratios than their prey, as organisms optimize growth by choosing the most nutrient-rich resources to consume and then preferentially retain nutrients over carbon in their bodies. Smaller organisms grow proportionally faster than large organisms and so are predicted to have higher nutrient requirements to fuel RNA and protein synthesis. Geography influenced the magnitude, more than the direction, of the ecological and/or phylogenetic effects on elemental composition. Overall, our results show that both ecological (i.e. trophic group) and evolutionary drivers explain among-taxa variation in the elemental content of invertebrates, whereas intraspecific variation is mainly a function of body size. Our findings also demonstrate that restricting analyses of macroinvertebrate stoichiometry solely to either the local scale or species level affects inferences of the patterns in invertebrate elemental content and their underlying mechanisms.  
  Address  
  Corporate Author Thesis  
  Publisher John Wiley & Sons, Ltd (10.1111) Place of Publication Editor  
  Language Summary Language Original Title  
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  ISSN 0269-8463 ISBN Medium  
  Area Expedition Conference  
  Notes doi: 10.1111/1365-2435.13197 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 849  
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Author Dlouhá, J.; Alméras, T.; Beauchene, J.; Clair, B.; Fournier, M. url  doi
openurl 
  Title Biophysical dependences among functional wood traits Type Journal Article
  Year 2018 Publication Functional Ecology Abbreviated Journal (down) Funct Ecol  
  Volume 32 Issue 12 Pages 2652-2665  
  Keywords basic density; biomechanical traits; hydraulic traits; wood traits  
  Abstract Abstract Wood properties and especially wood density have been used as functional traits organized along major axes of species life history and strategy. Beyond statistical analyses, a better mechanistic understanding of relationships among wood traits is essential for ecologically relevant interpretation of wood trait variations. A set of theoretical relationships mechanistically linking wood basic density with some other wood traits is derived from cellular material physics. These theoretical models picture basic physical constraints and thus provide null hypotheses for further ecological studies. Analysis is applied to data from two original datasets and several datasets extracted from the literature. Results emphasize the strong physical constraint behind the link between basic density and maximal storable water on the one hand, and elastic modulus on the other hand. Beyond these basic physical constraints, the developed framework reveals physically less expected trends: the amount of free water available for physiological needs increases in less dense wood of fast-growing species, and the cell wall stiffness decreases with density in temperate hardwoods and is higher in sapling stages in the rainforest understorey where competition for light is associated with high mechanical risk. We emphasize the use of theoretically independent traits derived from models of cellular material physics to investigate the functional variation of wood traits together with their environmental and phylogenetic variations. Although the current study is limited to basic density, green wood lumen saturation and wood specific modulus, we further emphasize the identification of complementary independent wood traits representing other biomechanical functions, nutrient storage, hydraulic conductance and resistance to drought. A plain language summary is available for this article.  
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  Publisher John Wiley & Sons, Ltd (10.1111) Place of Publication Editor  
  Language Summary Language Original Title  
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  ISSN 0269-8463 ISBN Medium  
  Area Expedition Conference  
  Notes doi: 10.1111/1365-2435.13209 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 851  
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Author Ziegler, C.; Dusenge, M.E.; Nyirambangutse, B.; Zibera, E.; Wallin, G.; Uddling, J. doi  openurl
  Title Contrasting Dependencies of Photosynthetic Capacity on Leaf Nitrogen in Early- and Late-Successional Tropical Montane Tree Species Type Journal Article
  Year 2020 Publication Frontiers in Plant Science Abbreviated Journal (down) Front. Plant Sci.  
  Volume 11 Issue Pages 500479  
  Keywords allocation; early successional; late successional; nitrogen; photosynthesis; tropical montane forests  
  Abstract Differences in photosynthetic capacity among tree species and tree functional types are currently assumed to be largely driven by variation in leaf nutrient content, particularly nitrogen (N). However, recent studies indicate that leaf N content is often a poor predictor of variation in photosynthetic capacity in tropical trees. In this study, we explored the relative importance of area-based total leaf N content (Ntot) and within-leaf N allocation to photosynthetic capacity versus light-harvesting in controlling the variation in photosynthetic capacity (i.e. Vcmax, Jmax) among mature trees of 12 species belonging to either early (ES) or late successional (LS) groups growing in a tropical montane rainforest in Rwanda, Central Africa. Photosynthetic capacity at a common leaf temperature of 25˚C (i.e. maximum rates of Rubisco carboxylation, Vcmax25 and of electron transport, Jmax25) was higher in ES than in LS species (+ 58% and 68% for Vcmax25 and Jmax25, respectively). While Ntot did not significantly differ between successional groups, the photosynthetic dependency on Ntot was markedly different. In ES species, Vcmax25 was strongly and positively related to Ntot but this was not the case in LS species. However, there was no significant trade-off between relative leaf N investments in compounds maximizing photosynthetic capacity versus compounds maximizing light harvesting. Both leaf dark respiration at 25˚C (+ 33%) and, more surprisingly, apparent photosynthetic quantum yield (+ 35%) was higher in ES than in LS species. Moreover, Rd25 was positively related to Ntot for both ES and LS species. Our results imply that efforts to quantify carbon fluxes of tropical montane rainforests would be improved if they considered contrasting within-leaf N allocation and photosynthetic Ntot dependencies between species with different successional strategies. © Copyright © 2020 Ziegler, Dusenge, Nyirambangutse, Zibera, Wallin and Uddling.  
  Address Department of Biology, The University of Western Ontario, London, ON, Canada  
  Corporate Author Thesis  
  Publisher Frontiers Media S.A. Place of Publication Editor  
  Language Summary Language Original Title  
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  ISSN 1664462x (Issn) ISBN Medium  
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  Call Number EcoFoG @ webmaster @ Serial 953  
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Author Bréchet, L.; Courtois, E.A.; Saint-Germain, T.; Janssens, I.A.; Asensio, D.; Ramirez-Rojas, I.; Soong, J.L.; Van Langenhove, L.; Verbruggen, E.; Stahl, C. pdf  url
doi  openurl
  Title Disentangling Drought and Nutrient Effects on Soil Carbon Dioxide and Methane Fluxes in a Tropical Forest Type Journal Article
  Year 2019 Publication Frontiers in Environmental Science Abbreviated Journal (down) Front. Environ. Sci.  
  Volume 7 Issue 180 Pages  
  Keywords carbon dioxide; drought; fertilization; methane; nitrogen; phosphorus; soil GHG fluxes; tropical forest  
  Abstract Tropical soils are a major contributor to the balance of greenhouse gas (GHG) fluxes in the atmosphere. Models of tropical GHG fluxes predict that both the frequency of drought events and changes in atmospheric deposition of nitrogen (N) will significantly affect dynamics of soil carbon dioxide (CO2) and methane (CH4) production and consumption. In this study, we examined the combined effect of a reduction in precipitation and an increase in nutrient availability on soil CO2 and CH4 fluxes in a primary French Guiana tropical forest. Drought conditions were simulated by intercepting precipitation falling through the forest canopy with tarpaulin roofs. Nutrient availability was manipulated through application of granular N and/or phosphorus (P) fertilizer to the soil. Soil water content (SWC) below the roofs decreased rapidly and stayed at continuously low values until roof removal, which as a consequence roughly doubled the duration of the dry season. After roof removal, SWC slowly increased but remained lower than in the control soils even after 2.5 months of wet-season precipitation. We showed that drought-imposed reduction in SWC decreased the CO2 emissions (i.e., CO2 efflux), but strongly increased the CH4 emissions. N, P, and N × P (i.e., NP) additions all significantly increased CO2 emission but had no effect on CH4 fluxes. In treatments where both fertilization and drought were applied, the positive effect of N, P, and NP fertilization on CO2 efflux was reduced. After roof removal, soil CO2 efflux was more resilient in the control plots than in the fertilized plots while there was only a modest effect of roof removal on soil CH4 fluxes. Our results suggest that a combined increase in drought and nutrient availability in soil can locally increase the emissions of both CO2 and CH4 from tropical soils, for a long term.  
  Address Lawrence Berkeley National Laboratory, Climate and Ecosystem Science Division, Berkeley, CA, United States  
  Corporate Author Thesis  
  Publisher Frontiers Media S.A. Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2296665x (Issn) ISBN Medium  
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  Notes Export Date: 16 December 2019; Correspondence Address: Bréchet, L.; Centre of Excellence PLECO (Plant and Ecosystems), Department of Biology, University of AntwerpBelgium; email: laeti.brechet@gmail.com Approved no  
  Call Number EcoFoG @ webmaster @ Serial 899  
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Author Dezerald, O.; Céréghino, R.; Corbara, B.; Dejean, A.; Leroy, C. url  openurl
  Title Functional trait responses of aquatic macroinvertebrates to simulated drought in a Neotropical bromeliad ecosystem Type Journal Article
  Year 2015 Publication Freshwater Biology Abbreviated Journal (down) Freshwater Biology  
  Volume 60 Issue 9 Pages 1917-1929  
  Keywords Food webs; Precipitations; Rainforests; Resistance/resilience; Tipping point  
  Abstract The duration of the dry seasons in south-eastern Amazonia is expected to increase. Little is known of how freshwater assemblages respond to drought in the humid rainforests and of the extent to which they resist the absence of rainfall before the collapse of the system. We manipulated rainshelters over tank-forming bromeliads (i.e. the interlocking leaf axils of these plants form wells that collect rainwater) to simulate an exceptionally long dry period (49 days, compared with a 10-year mean ± SD annual maximum number of 17 ± 5.3 days without rainfall at the study site) and then a rewetting period. By sampling weekly over 3 months, we followed the dynamics of the representation of abundance-weighted traits in invertebrate assemblages in these treatment plants and in a control group. The functional structure of assemblages was drought resistant until the water volume in the bromeliad pools dropped by 90%, when there was a sudden shift in the functional trait structure due to the loss of most populations except the drought-resistant culicids. Traits related to life history, body size and preferred food showed significant responses to drought. There was a convergence in the functional traits of species surviving in dry plants, strengthening the idea that environmental filtering, rather than stochasticity, determines the functional trajectory of aquatic assemblages during drought. At the end of the dry period, samples of the detritus potentially containing drought-resistant eggs/cysts (and eventually live larvae) were taken from the dry plants and rewetted in the laboratory, allowing us to distinguish resistant species from those requiring recolonisation via subsequent oviposition by adults from elsewhere. Patches of water-filled bromeliads persisting in the area provided the most important pool of colonists, and communities returned to the pre-disturbance state within 1-2 weeks of rewetting. Our results suggest that the functional trait structure of invertebrate assemblages in bromeliads could remain stable under scenarios of precipitation change that would triple the duration of current dry periods at a local scale. Future experiments should evaluate how environmental factors might alter the tipping point between resistance to drought and a collapse in ecosystem processes. © 2015 John Wiley & Sons Ltd.  
  Address IRD, UMR AMAP (botAnique et Modélisation de l'Architecture des Plantes et des vegetations), Boulevard de la Lironde, TA A-51/PS2, Montpellier Cedex 5, France  
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  Notes Export Date: 27 August 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 616  
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Author Brouard, O.; Céréghino, R.; Corbara, B.; Leroy, C.; Pelozuelo, L.; Dejean, A.; Carrias, J.-F. url  openurl
  Title Understorey environments influence functional diversity in tank-bromeliad ecosystems Type Journal Article
  Year 2012 Publication Freshwater Biology Abbreviated Journal (down) Freshw. Biol.  
  Volume 57 Issue 4 Pages 815-823  
  Keywords Food webs; French Guiana; Invertebrates; Microorganisms; Phytotelmata; Rainforest  
  Abstract A substantial fraction of the freshwater available in neotropical forests is impounded within the rosettes of bromeliads that form aquatic islands in a terrestrial matrix. The ecosystem functioning of bromeliads is known to be influenced by the composition of the contained community but it is not clear whether bromeliad food webs remain functionally similar against a background of variation in the understorey environment. We considered a broad range of environmental conditions, including incident light and incoming litter, and quantified the distribution of a very wide range of freshwater organisms (from viruses to macroinvertebrates) to determine the factors that influence the functional structure of bromeliad food webs in samples taken from 171 tank-bromeliads. We observed a gradient of detritus-based to algal-based food webs from the understorey to the overstorey. Algae, rotifers and collector and predatory invertebrates dominated bromeliad food webs in exposed areas, whereas filter-feeding insects had their highest densities in shaded forest areas. Viruses, bacteria and fungi showed no clear density patterns. Detritus decomposition is mainly due to microbial activity in understorey bromeliads where filter feeders are the main consumers of microbial and particulate organic matter (POM). Algal biomass may exceed bacterial biomass in sun-exposed bromeliads where amounts of detritus were lower but functional diversity was highest. Our results provide evidence that tank-bromeliads, which grow in a broad range of ecological conditions, promote aquatic food web diversity in neotropical forests. Moreover, although bromeliad ecosystems have been categorised as detritus-based systems in the literature, we show that algal production can support a non-detrital food web in these systems. © 2012 Blackwell Publishing Ltd.  
  Address Ecologie des Forêts de Guyane, UMR, CNRS 8172, Campus Agronomique, 97379 Kourou Cedex, France  
  Corporate Author Thesis  
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  ISSN 00465070 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 21 March 2012; Source: Scopus; Coden: Fwbla; doi: 10.1111/j.1365-2427.2012.02749.x; Language of Original Document: English; Correspondence Address: Céréghino, R.; INP, UPS EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), Université de Toulouse, 118 Route de Narbonne, 31062 Toulouse, France; email: regis.cereghino@univ-tlse3.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 383  
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Author Dezerald, O.; Leroy, C.; Corbara, B.; Dejean, A.; Talaga, S.; Céréghino, R. doi  openurl
  Title Environmental drivers of invertebrate population dynamics in Neotropical tank bromeliads Type Journal Article
  Year 2017 Publication Freshwater Biology Abbreviated Journal (down) Freshw Biol  
  Volume 62 Issue 2 Pages 229-242  
  Keywords food webs; freshwater invertebrates; growth rate; life history; rainforest  
  Abstract Tank bromeliads form a conspicuous, yet neglected freshwater habitat in Neotropical forests. Recent studies driven by interests in medical entomology, fundamental aspects of bromeliad ecology and experimental research on food webs have, however, prompted increasing interest in bromeliad aquatic ecosystems. As yet, there is nothing in the literature about the life histories and environmental drivers of invertebrate population dynamics in tank bromeliads.

Based on fortnightly samples taken over one year, size frequency plots and individual dry masses allowed us to establish the life cycles and growth rates of the dominant aquatic invertebrates in a common bromeliad species of French Guiana. Linear mixed-effect models and Mantel tests were used to predict changes in density, biomass, and growth rates in relation to temperature, rainfall, humidity and detrital resources.

Annual variations in invertebrate densities and biomasses could be described according to three types of distribution: unimodal, bimodal or almost constant. Despite seasonal variations, precipitation, temperature, relative humidity and detritus concentration accounted significantly for changes in density and biomass, but we found no significant responses in growth rates of most invertebrate species. Species rather displayed non-seasonal life cycles with overlapping cohorts throughout the year. There was also a trend for delayed abundance peaks among congeneric species sharing similar functional traits, suggesting temporal partitioning of available resources.

Beyond novel knowledge, quantitative information on life histories is important to predict food-web dynamics under the influence of external forcing and self-organisation. Our results suggest that changes in species distribution that will affect population dynamics through biotic interactions in space and/or time could have greater effects on food webs and ecosystem functioning than changes in environmental factors per se.
 
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  ISSN 1365-2427 ISBN Medium  
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  Call Number EcoFoG @ webmaster @ Serial 716  
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Author Fargeon, H.; Aubry-Kientz, M.; Brunaux, O.; Descroix, L.; Gaspard, R.; Guitet, S.; Rossi, V.; Herault, B. pdf  url
doi  openurl
  Title Vulnerability of commercial tree species to water stress in logged forests of the Guiana shield Type Journal Article
  Year 2016 Publication Forests Abbreviated Journal (down) Forests  
  Volume 7 Issue 5 Pages  
  Keywords Climate change; Growth rates; Mortality rates; Paracou; Selective logging  
  Abstract The future of tropical managed forests is threatened by climate change. In anticipation of the increase in the frequency of drought episodes predicted by climatic models for intertropical regions, it is essential to study commercial trees' resilience and vulnerability to water stress by identifying potential interaction effects between selective logging and stress due to a lack of water. Focusing on 14 species representing a potential or acknowledged commercial interest for wood production in the Guiana Shield, a joint model coupling growth and mortality for each species was parametrized, including a climatic variable related to water stress and the quantity of aboveground biomass lost after logging. For the vast majority of the species, water stress had a negative impact on growth rate, while the impact of logging was positive. The opposite results were observed for the mortality. Combining results from growth and mortality models, we generate vulnerability profiles and ranking from species apparently quite resistant to water stress (Chrysophyllum spp., Goupia glabra Aubl., Qualea rosea Aubl.), even under logging pressure, to highly vulnerable species (Sterculia spp.). In light of our results, forest managers in the Guiana Shield may want to conduct (i) a conservation strategy of the most vulnerable species and (ii) a diversification of the logged species. Conservation of the already-adapted species may also be considered as the most certain way to protect the tropical forests under future climates. © 2016 by the authors.  
  Address Université de Yaoundé I, UMMISCO (UMI 209), Yaoundé, Cameroon  
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  Notes Export Date: 11 June 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 682  
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Author Aguilos, M.; Stahl, C.; Burban, B.; Hérault, B.; Courtois, E.; Coste, S.; Wagner, F.; Ziegler, C.; Takagi, K.; Bonal, D. pdf  url
doi  openurl
  Title Interannual and seasonal variations in ecosystem transpiration and water use efficiency in a tropical rainforest Type Journal Article
  Year 2018 Publication Forests Abbreviated Journal (down) Forests  
  Volume 10 Issue 1 Pages  
  Keywords Drought; Evapotranspiration; Radiation; Tropical rainforest; Water use efficiency; Atmospheric radiation; Carbon dioxide; Climate change; Drought; Efficiency; Evapotranspiration; Forestry; Heat radiation; Radiation effects; Soil moisture; Tropics; Water supply; Climate condition; Drought conditions; Interannual variability; Mechanistic models; Seasonal variation; Tropical ecosystems; Tropical rain forest; Water use efficiency; Ecosystems  
  Abstract Warmer and drier climates over Amazonia have been predicted for the next century with expected changes in regional water and carbon cycles. We examined the impact of interannual and seasonal variations in climate conditions on ecosystem-level evapotranspiration (ET) and water use efficiency (WUE) to determine key climatic drivers and anticipate the response of these ecosystems to climate change. We used daily climate and eddyflux data recorded at the Guyaflux site in French Guiana from 2004 to 2014. ET and WUE exhibited weak interannual variability. The main climatic driver of ET and WUE was global radiation (Rg), but relative extractable water (REW) and soil temperature (Ts) did also contribute. At the seasonal scale, ET and WUE showed a modal pattern driven by Rg, with maximum values for ET in July and August and for WUE at the beginning of the year. By removing radiation effects during water depleted periods, we showed that soil water stress strongly reduced ET. In contrast, drought conditions enhanced radiation-normalized WUE in almost all the years, suggesting that the lack of soil water had a more severe effect on ecosystem evapotranspiration than on photosynthesis. Our results are of major concern for tropical ecosystem modeling because they suggest that under future climate conditions, tropical forest ecosystems will be able to simultaneously adjust CO2 and H2O fluxes. Yet, for tropical forests under future conditions, the direction of change in WUE at the ecosystem scale is hard to predict, since the impact of radiation on WUE is counterbalanced by adjustments to soil water limitations. Developing mechanistic models that fully integrate the processes associated with CO2 and H2O flux control should help researchers understand and simulate future functional adjustments in these ecosystems.  
  Address Hokkaido University, Sapporo, 060-0808, Japan  
  Corporate Author Thesis  
  Publisher Mdpi Ag Place of Publication Editor  
  Language Summary Language Original Title  
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  ISSN 19994907 (Issn) ISBN Medium  
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  Notes Export Date: 1 February 2019; Correspondence Address: Bonal, D.; Université de Lorraine, AgroParisTech, INRA, UMR SilvaFrance; email: damien.bonal@inra.fr; References: Von Randow, C., Zeri, M., Restrepo-Coupe, N., Muza, M.N., de Gonçalves, L.G.G., Costa, M.H., Araujo, A.C., Saleska, S.R., Interannual variability of carbon and water fluxes in Amazonian forest, Cerrado and pasture sites, as simulated by terrestrial biosphere models (2013) Agric. For. Meteorol, 182-183, pp. 145-155; Duffy, P.B., Brando, P., Asner, G.P., Field, C.B., Projections of future meteorological drought and wet periods in the Amazon (2015) Proc. Natl. Acad. Sci. USA, 112, pp. 13172-13177; Cox, P.M., Betts, R.A., Collins, M., Harris, P.P., Huntingford, C., Jones, C.D., Amazonian forest dieback under climate-carbon cycle projections for the 21st century (2004) Theor. Appl. Climatol, 78, pp. 137-156; Poulter, B., Hattermann, F., Hawkins, E., Zaehle, S., Sitch, S., Restrepo-Coupe, N., Heyder, U., Cramer, W., Robust dynamics of Amazon dieback to climate change with perturbed ecosystem model parameters (2010) Glob. Chang. Biol, 16, pp. 2476-2495; Saleska, S.R., Didan, K., Huete, A.R., Da Rocha, H.R., Amazon forests green-up during 2005 drought (2007) Science, 318, p. 612; Phillips, O.L., Aragão, L.E.O.C., Lewis, S.L., Fisher, J.B., Lloyd, J., López-González, G., Malhi, Y., Quesada, C.A., Drought sensitivity of the amazon rainforest (2009) Science, 323, pp. 1344-1347; Bonal, D., Burban, B., Stahl, C., Wagner, F., Hérault, B., The response of tropical rainforests to drought-Lessons from recent research and future prospects (2016) Ann. For. Sci, 73, pp. 27-44; Wang, K.C., Dickinson, R.E., A review of global terrestrial evapotranspiration: Observation, modeling, climatology, and climatic variability (2012) Rev. Geophys, p. 50; Fisher, R.A., Williams, M., da Costa, A.L., Malhi, Y., da Costa, R.F., Almeida, S., Meir, P., The response of an Eastern Amazonian rain forest to drought stress: Results and modelling analyses from a throughfall exclusion experiment (2007) Glob. Chang. Biol, 13, pp. 2361-2378; Costa, M.H., Biajoli, M.C., Sanches, L., Malhado, A.C.M., Hutyra, L.R., Da Rocha, H.R., Aguiar, R.G., De Araújo, A.C., Atmospheric versus vegetation controls of Amazonian tropical rain forest evapotranspiration: Are the wet and seasonally dry rain forests any different? (2010) J. Geophys. Res. Biogeosci, 115, pp. 1-9; Carswell, F.E., Costa, A.L., Palheta, M., Malhi, Y., Meir, P., Costa, J.D.P.R., Ruivo, M.D.L., Clement, R.J., Seasonality in CO2 and H2O flux at an eastern Amazonian rain forest (2002) J. Geophys. Res. D Atmos, 107, p. 8076; Hasler, N., Avissar, R., What controls evapotranspiration in the Amazon basin? (2007) J. Hydrometeorol, 8, pp. 380-395; Da Rocha, H.R., Manzi, A.O., Cabral, O.M., Miller, S.D., Goulden, M.L., Saleska, S.R., Coupe, N.R., Artaxo, R., Patterns of water and heat flux across a biome gradient from tropical forest to savanna in brazil (2009) J. Geophys. Res. Biogeosci, p. 114; Kim, Y., Knox, R.G., Longo, M., Medvigy, D., Hutyra, L.R., Pyle, E.H., Wofsy, S.C., Moorcroft, P.R., Seasonal carbon dynamics and water fluxes in an Amazon rainforest (2012) Glob. Chang. Biol, 18, pp. 1322-1334; Maeda, E.E., Ma, X., Wagner, F.H., Kim, H., Oki, T., Eamus, D., Huete, A., Evapotranspiration seasonality across the Amazon Basin (2017) Earth Syst. Dyn, 8, pp. 439-454; Farquhar, G.D., Ehleringer, J.R., Hubick, K.T., Carbon isotope discrimination and photosynthesis (1989) Ann. Rev. Plant Physiol, 40, pp. 503-537; Hutyra, L.R., Munger, J.W., Saleska, S.R., Gottlieb, E., Daube, B.C., Dunn, A.L., Amaral, D.F., Wofsy, S.C., Seasonal controls on the exchange of carbon and water in an Amazonian rain forest (2007) J. Geophys. Res. Biogeosci; Negrón Juárez, R.I., Hodnett, M.G., Fu, R., Gouden, M.L., von Randow, C., Control of dry season evapotranspiration over the Amazonian forest as inferred from observation at a Southern Amazon forest site (2007) J. Clim, 20, pp. 2827-2839; Fisher, J.B., Malhi, Y., Bonal, D., Da Rocha, H.R., De Araújo, A.C., Gamo, M., Goulden, M.L., Kondo, H., The land-atmosphere water flux in the tropics (2009) Glob. Chang. Biol; Christoffersen, B.O., Restrepo-Coupe, N., Arain, M.A., Baker, I.T., Cestaro, B.P., Ciais, P., Fisher, J.B., Gulden, L., Mechanisms of water supply and vegetation demand govern the seasonality and magnitude of evapotranspiration in Amazonia and Cerrado (2014) Agric. For. Meteorol, 191, pp. 33-50; Da Costa, A.C.L., Rowland, L., Oliveira, R.S., Oliveira, A.A.R., Binks, O.J., Salmon, Y., Vasconcelos, S.S., Poyatos, R., Stand dynamics modulate water cycling and mortality risk in droughted tropical forest (2018) Glob. Chang. Biol; Huang, M., Piao, S., Sun, Y., Ciais, P., Cheng, L., Mao, J., Poulter, B., Wang, Y., Change in terrestrial ecosystem water-use efficiency over the last three decades (2015) Glob. Chang. Biol; Brienen, R.J.W., Wanek, W., Hietz, P., Stable carbon isotopes in tree rings indicate improved water use efficiency and drought responses of a tropical dry forest tree species (2011) Trees, 25, pp. 103-113; Yu, G., Song, X., Wang, Q., Liu, Y., Guan, D., Yan, J., Sun, X., Wen, X., Water-use efficiency of forest ecosystems in eastern China and its relations to climatic variables (2008) New Phytol, 177, pp. 927-937; Aguilos, M., Hérault, B., Burban, B., Wagner, F., Bonal, D., What drives long-term variations in carbon flux and balance in a tropical rainforest in French Guiana? Agric (2018) For. Meteorol, pp. 253-254; Bonal, D., Bosc, A., Ponton, S., Goret, J.Y., Burban, B.T., Gross, P., Bonnefond, J.M., Epron, D., Impact of severe dry season on net ecosystem exchange in the Neotropical rainforest of French Guiana (2008) Glob. Chang. Biol; Aubinet, M., Grelle, A., Ibrom, A., Rannik, U., Moncrieff, J.B., Foken, T., Kowalski, A.S., Bernhofer, C., Estimates of the annual net carbon and water exchange of forests: The Euroflux methodology (2000) Adv. Ecol. Res, 30, pp. 113-175; Wagner, F., Hérault, B., Stahl, C., Bonal, D., Rossi, V., Modeling water availability for trees in tropical forests (2011) Agric. For. Meteorol, 151, pp. 1202-1213; Kuglitsch, F.G., Reichstein, M., Beer, C., Carrara, A., Ceulemans, R., Granier, A., Janssens, I.A., Loustau, D., Characterisation of ecosystem water-use efficiency of european forests from eddy covariance measurements (2008) Biogeosci. Discuss, 5, pp. 4481-4519; Dekker, S.C., Groenendijk, M., Booth, B.B.B., Huntingford, C., Cox, P.M., Spatial and temporal variations in plant water-use efficiency inferred from tree-ring, eddy covariance and atmospheric observations (2016) Earth Syst. Dyn, 7, pp. 525-533; Yang, Y., Guan, H., Batelaan, O., McVicar, T.R., Long, D., Piao, S., Liang, W., Simmons, C.T., Contrasting responses of water use efficiency to drought across global terrestrial ecosystems (2016) Sci. Rep, 6, p. 23284; Granier, A., Bréda, N., Biron, P., Villette, S., A lumped water balance model to evaluate duration and intensity of drought constraints in forest stands (1999) Ecol. Model, 116, pp. 269-283; Kume, T., Takizawa, H., Yoshifuji, N., Tanaka, K., Tantasirin, C., Tanaka, N., Suzuki, M., Impact of soil drought on sap flow and water status of evergreen trees in a tropical monsoon forest in northern Thailand (2007) For. Ecol. Manag, 238, pp. 220-230; Xiao, J., Sun, G., Chen, J., Chen, H., Chen, S., Dong, G., Gao, S., Han, S., Carbon fluxes, evapotranspiration, and water use efficiency of terrestrial ecosystems in China (2013) Agric. For. Meteorol; Boese, S., Jung, M., Carvalhais, N., Reichstein, M., The importance of radiation for semi-empirical water-use efficiency models (2017) Biogeosciences, 14, pp. 3015-3026; Bonal, D., Ponton, S., Le Thiec, D., Richard, B., Ningre, N., Hérault, B., Ogée, J., Sabatier, D., Leaf functional response to increasing atmospheric CO2 concentrations over the last century in two northern Amazonian tree species: An historical δ13C and δ18O approach using herbarium samples (2011) Plant Cell Environ, 34, pp. 1332-1344; Wagner, F., Rossi, V., Stahl, C., Bonal, D., Hérault, B., Water availability is the main climate driver of neotropical tree growth (2012) PLoS ONE, 7; Van der Molen, M.K., Dolman, A.J., Ciais, P., Eglin, T., Gobron, N., Law, B.E., Meir, P., Reichstein, M., Drought and ecosystem carbon cycling (2011) Agric. For. Meteorol, 151, pp. 765-773; Allen, C.D., Macalady, A.K., Chenchouni, H., Bachelet, D., McDowell, N., Vennetier, M., Kitzberger, T., Hogg, E.H., A global overview of drought and heat-induced tree mortality reveals emerging climate change risks for forests (2010) For. Ecol. Manag, 259, pp. 660-684; Da Rocha, H.R., Goulden, M.L., Miller, S.D., Menton, M.C., Pinto, L.D., De Freitas, H.C., Seasonality of water and heat fluxes over a tropical forest in eastern Amazonia (2004) Ecol. Appl, 14, pp. 22-32; Baldocchi, D., Falge, E., Gu, L., Olson, R., Hollinger, D., Running, S., Anthoni, P., Evans, R., FLUXNET: A New tool to study the temporal and spatial variability of ecosystem-scale carbon dioxide, water vapor, and energy flux densities (2001) Bull. Am. Meteorol. Soc, 82, pp. 2415-2434; Stahl, C., Hérault, B., Rossi, V., Burban, B., Bréchet, C., Bonal, D., Depth of soil water uptake by tropical rainforest trees during dry periods: Does tree dimension matter? (2013) Oecologia, 173, pp. 1191-1201; Nepstad, D.C., De Carvalho, C.R., Davidson, E.A., Jipp, P.H., Lefebvre, P.A., Negreiros, G.H., Da Silva, E.D., Vieira, S., The role of deep roots in the hydrological and carbon cycles of Amazonian forests and pastures (1994) Nature; Lee, J.-E., Boyce, K., Impact of the hydraulic capacity of plants on water and carbon fluxes in tropical South America (2010) J. Geophys. Res; Xiao, X., Zhang, Q., Saleska, S., Hutyra, L., De Camargo, P., Wofsy, S., Frolking, S., Moore, B., Satellite-based modeling of gross primary production in a seasonally moist tropical evergreen forest (2005) Remote Sens. Environ, 94, pp. 105-122; Wagner, F.H., Hérault, B., Bonal, D., Stahl, C., Anderson, L.O., Baker, T.R., Becker, G.S., Botosso, P.C., Climate seasonality limits leaf carbon assimilation and wood productivity in tropical forests (2016) Biogeosciences, 13, pp. 2537-2562; Stahl, C., Burban, B., Wagner, F., Goret, J.-Y., Bompy, F., Bonal, D., Influence of Seasonal Variations in Soil Water Availability on Gas Exchange of Tropical Canopy Trees (2013) Biotropica, 45, pp. 155-164; Maréchaux, I., Bonal, D., Bartlett, M.K., Burban, B., Coste, S., Courtois, E.A., Dulormne, M., Mirabel, A., Dry-season decline in tree sapflux is correlated with leaf turgor loss point in a tropical rainforest (2018) Funct. Ecol, 32, pp. 2285-2297; Chaves, M.M., Maroco, J.P., Pereira, J.S., Understanding plant responses to drought-from genes to the whole plant (2003) Funct. Plant Biol, 30, pp. 239-264 Approved no  
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