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Author Bourguignon, T.; Sobotnik, J.; Lepoint, G.; Martin, J.M.; Roisin, Y.
Title Niche differentiation among neotropical soldierless soil-feeding termites revealed by stable isotope ratios Type Journal Article
Year 2009 Publication Soil Biology & Biochemistry Abbreviated Journal Soil Biol. Biochem.
Volume 41 Issue 10 Pages 2038-2043
Keywords Anoplotermes; Termitidae; Isoptera; Resource partitioning; Food web; Decomposition gradient
Abstract Termites represent one of the most abundant belowground animal taxa in tropical rainforests, where their species richness is much higher than in any other ecosystem. This high diversity in soil ecosystems is however difficult to explain by classical Hutchinsonian niche theory, as there is little evidence for spatial or temporal separation between species. Using delta C-13 and delta N-15 isotopic ratios, we tested if resource partitioning along the humification gradient occurs; in neotropical soldierless termites of the Anoplotermes-group. Two distinct sites were investigated to check if interspecific differences are transposable between sites. Significant differences in delta N-15 were found between species of the Anoplotermes-group. Although some species displayed higher intersite delta N-15 variation than others, species-average delta N-15 values for both sites were highly correlated, showing that sympatric soldierless soil-feeding termites feed on distinct components of the soil. Our data also suggest that some species are more likely to shift along this gradient than others, in response to overall habitat conditions or to the presence of competitors. Feeding niche differentiation can therefore account for the high species richness and diversity of soldierless soil-feeding termites in neotropical rainforests. (C) 2009 Elsevier Ltd. All rights reserved.
Address [Bourguignon, Thomas; Roisin, Yves] Univ Libre Bruxelles, B-1050 Brussels, Belgium, Email: yroisin@ulb.ac.be
Corporate Author Thesis
Publisher PERGAMON-ELSEVIER SCIENCE LTD Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-0717 ISBN Medium
Area Expedition Conference
Notes ISI:000271047800003 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 98
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Author Tremolieres, M.; Noel, V.; Herault, B.
Title Phosphorus and nitrogen allocation in Allium ursinum on an alluvial floodplain (Eastern France). Is there an effect of flooding history? Type Journal Article
Year 2009 Publication Plant and Soil Abbreviated Journal Plant Soil
Volume 324 Issue 1-2 Pages 279-289
Keywords Allium ursinum; Flooding history; Nitrogen; Nutrient bioavailability; Phosphorus; Rhine
Abstract The change in phosphorus and nitrogen content in a common geophyte spring species, Allium ursinum, is studied in alluvial forests in relation to three flooding histories related to river regulation: (1) annually flooded, (2) unflooded for 30 years, and (3) unflooded for 200 years. Flood suppression leads to a reduction of available P soil content as well as decreasing the biomass and the amount of phosphorus in plants, but has no significant effect on N plant content. Plant N:P ratio increases with the suppression of floods and is primarily driven by soil N:P ratios, in turn markedly linked to the total nitrogen in the soil. We highlighted a lower nutrient accumulation in leaves during plant growth in unflooded forests. Overall, our results suggest that P was the main limiting factor in unflooded forests while nitrogen was the main limiting factor in annually flooded forests. Flood suppression strongly affects the morphology and nutrient uptake by Allium ursinum and thus nutrient cycling in riverine forests.
Address [Tremolieres, Michele; Noel, Valerie] Inst Bot, LHYGES, UMR 7517, F-67083 Strasbourg, France, Email: michele.tremolieres@bota-ulp.u-strasbg.fr
Corporate Author Thesis
Publisher SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0032-079X ISBN Medium
Area Expedition Conference
Notes ISI:000271028800020 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 99
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Author Coste, S.; Roggy, J.C.; Garraud, L.; Heuret, P.; Nicolini, E.; Dreyer, E.
Title Does ontogeny modulate irradiance-elicited plasticity of leaf traits in saplings of rain-forest tree species? A test with Dicorynia guianensis and Tachigali melinonii (Fabaceae, Caesalpinioideae) Type Journal Article
Year 2009 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.
Volume 66 Issue 7 Pages 701-709
Keywords plant architecture; phenotypic plasticity; photosynthetic capacity; leaf structure; tropical rain forest
Abstract Irradiance elicits a large plasticity in leaf traits, but little is known about the modulation of this plasticity by ontogeny. Interactive effects of relative irradiance and ontogeny were assessed on leaf traits for two tropical rainforest tree species: Dicorynia guianensis Amshoff and Tachigali melinonii (Harms) Barneby (Fabaceae, Caesalpinioideae). Eleven morphological and physiological leaf traits, relative to photosynthetic performance, were measured on saplings at three different architectural development stages (ASD 1, 2 and 3) and used to derive composite traits like photosynthetic N-use efficiency. Measurements were made along a natural irradiance gradient. The effect of ASD was very visible and differed between the two species. For Dicorynia guianensis, only leaf mass-per-area (LMA) significantly increased with ASDs whereas for Tachigali melinonii, almost all traits were affected by ASD: LMA, leaf N content and photosynthetic capacity increased from ASD 1 to ASD 3. Photosynthetic N-use-efficiency was not affected by ASD in any species. Leaf traits were severely modulated by irradiance, whereas the degree of plasticity was very similar among ASDs. Only few interactions were detected between irradiance and ASD, for leaf thickness, carbon content, and the ratio Chl/N in T. melinonii and for photosynthetic capacity in D. guianensis. We conclude that ontogenic development and irradiance-elicited plasticity modulated leaf traits, with almost no interaction, i.e., the degree of irradiance-elicited plasticity was stable across development stages and independent of ontogeny in these two species, at least in the early stages of development assessed here.
Address [Dreyer, Erwin] INRA, UMR Ecol & Ecophysiol Forestieres 1137, F-54280 Champenoux, France, Email: dreyer@nancy.inra.fr
Corporate Author Thesis
Publisher EDP SCIENCES S A Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1286-4560 ISBN Medium
Area Expedition Conference
Notes ISI:000270906600009 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 100
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Author Fisher, J.B.; Malhi, Y.; Bonal, D.; Da Rocha, H.R.; De Araujo, A.C.; Gamo, M.; Goulden, M.L.; Hirano, T.; Huete, A.R.; Kondo, H.; Kumagai, T.; Loescher, H.W.; Miller, S.; Nobre, A.D.; Nouvellon, Y.; Oberbauer, S.F.; Panuthai, S.; Roupsard, O.; Saleska, S.; Tanaka, K.; Tanaka, N.; Tu, K.P.; Von Randow, C.
Title The land-atmosphere water flux in the tropics Type Journal Article
Year 2009 Publication Global Change Biology Abbreviated Journal Glob. Change Biol.
Volume 15 Issue 11 Pages 2694-2714
Keywords Amazon; eddy covariance; evaporation; evapotranspiration; ISLSCP-II; LBA; model; remote sensing; tropical
Abstract Tropical vegetation is a major source of global land surface evapotranspiration, and can thus play a major role in global hydrological cycles and global atmospheric circulation. Accurate prediction of tropical evapotranspiration is critical to our understanding of these processes under changing climate. We examined the controls on evapotranspiration in tropical vegetation at 21 pan-tropical eddy covariance sites, conducted a comprehensive and systematic evaluation of 13 evapotranspiration models at these sites, and assessed the ability to scale up model estimates of evapotranspiration for the test region of Amazonia. Net radiation was the strongest determinant of evapotranspiration (mean evaporative fraction was 0.72) and explained 87% of the variance in monthly evapotranspiration across the sites. Vapor pressure deficit was the strongest residual predictor (14%), followed by normalized difference vegetation index (9%), precipitation (6%) and wind speed (4%). The radiation-based evapotranspiration models performed best overall for three reasons: (1) the vegetation was largely decoupled from atmospheric turbulent transfer (calculated from X decoupling factor), especially at the wetter sites; (2) the resistance-based models were hindered by difficulty in consistently characterizing canopy (and stomatal) resistance in the highly diverse vegetation; (3) the temperature-based models inadequately captured the variability in tropical evapotranspiration. We evaluated the potential to predict regional evapotranspiration for one test region: Amazonia. We estimated an Amazonia-wide evapotranspiration of 1370 mm yr(-1), but this value is dependent on assumptions about energy balance closure for the tropical eddy covariance sites; a lower value (1096 mm yr(-1)) is considered in discussion on the use of flux data to validate and interpolate models.
Address [Fisher, Joshua B.; Malhi, Yadvinder] Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford OX1 3QY, England, Email: joshbfisher@gmail.com
Corporate Author Thesis
Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1354-1013 ISBN Medium
Area Expedition Conference
Notes ISI:000270662000011 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 101
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Author van Gorsel, E.; Delpierre, N.; Leuning, R.; Black, A.; Munger, J.W.; Wofsy, S.; Aubinet, M.; Feigenwinter, C.; Beringer, J.; Bonal, D.; Chen, B.Z.; Chen, J.Q.; Clement, R.; Davis, K.J.; Desai, A.R.; Dragoni, D.; Etzold, S.; Grunwald, T.; Gu, L.H.; Heinesch, B.; Hutyra, L.R.; Jans, W.W.P.; Kutsch, W.; Law, B.E.; Leclerc, M.Y.; Mammarella, I.; Montagnani, L.; Noormets, A.; Rebmann, C.; Wharton, S.
Title Estimating nocturnal ecosystem respiration from the vertical turbulent flux and change in storage of CO2 Type Journal Article
Year 2009 Publication Agricultural and Forest Meteorology Abbreviated Journal Agric. For. Meteorol.
Volume 149 Issue 11 Pages 1919-1930
Keywords Ecosystem respiration; Micrometeorology; Advection; u-star correction; Eddy covariance; Chamber; Process-based modelling
Abstract Micrometeorological measurements of night time ecosystem respiration can be systematically biased when stable atmospheric conditions lead to drainage flows associated with decoupling of air flow above and within plant canopies. The associated horizontal and vertical advective fluxes cannot be measured using instrumentation on the single towers typically used at micrometeorological sites. A common approach to minimize bias is to use a threshold in friction velocity, u*, to exclude periods when advection is assumed to be important, but this is problematic in situations when in-canopy flows are decoupled from the flow above. Using data from 25 flux stations in a wide variety of forest ecosystems globally, we examine the generality of a novel approach to estimating nocturnal respiration developed by van Gorsel et al. (van Gorsel, E., Leuning, R., Cleugh, H.A., Keith, H., Suni, T., 2007. Nocturnal carbon efflux: reconciliation of eddy covariance and chamber measurements using an alternative to the u*-threshold filtering technique. Tellus 59B, 397-403, Tellus, 59B, 307-403). The approach is based on the assumption that advection is small relative to the vertical turbulent flux (F-C) and change in storage (F-S) of CO2 in the few hours after sundown. The sum of F-C and F-S reach a maximum during this period which is used to derive a temperature response function for ecosystem respiration. Measured hourly soil temperatures are then used with this function to estimate respiration R-Rmax. The new approach yielded excellent agreement with (1) independent measurements using respiration chambers, (2) with estimates using ecosystem light-response curves of F-c + F-s extrapolated to zero light, R-LRC, and (3) with a detailed process-based forest ecosystem model, R-cast. At most sites respiration rates estimated using the u*-filter, R-ust, were smaller than R-Rmax, and R-LRC. Agreement of our approach with independent measurements indicates that R-Rmax, provides an excellent estimate of nighttime ecosystem respiration. (C) 2009 Elsevier B.V. All rights reserved.
Address [van Gorsel, Eva; Leuning, Ray] CSIRO Marine & Atmospher Res, Canberra, ACT 2061, Australia, Email: Eva.vangorsel@csiro.au
Corporate Author Thesis
Publisher ELSEVIER SCIENCE BV Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-1923 ISBN Medium
Area Expedition Conference
Notes ISI:000270640300013 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 102
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Author Cachet, N.; Hoakwie, F.; Bertani, S.; Bourdy, G.; Deharo, E.; Stien, D.; Houel, E.; Gornitzka, H.; Fillaux, J.; Chevalley, S.; Valentin, A.; Jullian, V.
Title Antimalarial Activity of Simalikalactone E, a New Quassinoid from Quassia amara L. (Simaroubaceae) Type Journal Article
Year 2009 Publication Antimicrobial Agents and Chemotherapy Abbreviated Journal Antimicrob. Agents Chemother.
Volume 53 Issue 10 Pages 4393-4398
Keywords
Abstract We report the isolation and identification of a new quassinoid named simalikalactone E (SkE), extracted from a widely used Amazonian antimalarial remedy made out of Quassia amara L. (Simaroubaceae) leaves. This new molecule inhibited the growth of Plasmodium falciparum cultured in vitro by 50%, in the concentration range from 24 to 68 nM, independently of the strain sensitivity to chloroquine. We also showed that this compound was able to decrease gametocytemia with a 50% inhibitory concentration sevenfold lower than that of primaquine. SkE was found to be less toxic than simalikalactone D (SkD), another antimalarial quassinoid from Q. amara, and its cytotoxicity on mammalian cells was dependent on the cell line, displaying a good selectivity index when tested on nontumorogenic cells. In vivo, SkE inhibited murine malaria growth of Plasmodium vinckei petteri by 50% at 1 and 0.5 mg/kg of body weight/day, by the oral or intraperitoneal routes, respectively. The contribution of quassinoids as a source of antimalarial molecules needs therefore to be reconsidered.
Address [Cachet, N.; Hoakwie, F.; Bourdy, G.; Deharo, E.; Chevalley, S.; Valentin, A.; Jullian, V.] Univ Toulouse, UPS, Lab Pharmacochim Subst Nat & Pharmacophores Redox, UMR 152, F-31062 Toulouse 9, France, Email: jullian@cict.fr
Corporate Author Thesis
Publisher AMER SOC MICROBIOLOGY Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0066-4804 ISBN Medium
Area Expedition Conference
Notes ISI:000270020600047 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 103
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Author Roux, O.; Martin, J.M.; Ghomsi, N.T.; Dejean, A.
Title A Non-lethal Water-based Removal-reapplication Technique for Behavioral Analysis of Cuticular Compounds of Ants Type Journal Article
Year 2009 Publication Journal of Chemical Ecology Abbreviated Journal J. Chem. Ecol.
Volume 35 Issue 8 Pages 904-912
Keywords Ants; Behavioral assay; Behavioral ecology; Camponotus blandus; Chemical composition; Chemical ecology; Cuticular hydrocarbons; Gas chromatography-mass spectrometry; Live dummies; Solenopsis saevissima; Methods
Abstract Interspecific relationships among insects are often mediated by chemical cues, including non-volatile cuticular compounds. Most of these compounds are hydrocarbons that necessitate the use of solvents for their extraction, identification, and manipulation during behavioral assays. The toxicity of these solvents often precludes the removal and reapplication of hydrocarbons from and to live insects. As a consequence, dummies often are used in behavioral assays, but their passivity can bias the behavior of the responding insects. To overcome these limitations, we propose a method where cuticular compounds are extracted from live ants by placing them into glass vials half-filled with tepid water (ca. 34A degrees C) and vigorously shaking the vials to form an emulsion whose supernatant can be analyzed and/or reapplied to other ants. We demonstrate that cuticular compounds can be extracted from workers of the red fire ant, Solenopsis saevissima, and reapplied to the cuticle of workers from a sympatric species, Camponotus blandus (both Hymenoptera: Formicidae), while keeping the ants alive. Gas chromatographic-mass spectrometric analysis and behavioral assays were used to confirm the successful transfer of the behaviorally active compounds.
Address [Roux, Olivier; Martin, Jean-Michel; Dejean, Alain] Ecol Forets Guyane, CNRS, UMR 8172, F-97379 Kourou, France, Email: oroux@cict.fr
Corporate Author Thesis
Publisher SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0098-0331 ISBN Medium
Area Expedition Conference
Notes ISI:000269954400006 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 104
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Author Blanc, L.; Echard, M.; Herault, B.; Bonal, D.; Marcon, E.; Chave, J.; Baraloto, C.
Title Dynamics of aboveground carbon stocks in a selectively logged tropical forest Type Journal Article
Year 2009 Publication Ecological Applications Abbreviated Journal Ecol. Appl.
Volume 19 Issue 6 Pages 1397-1404
Keywords aboveground biomass; carbon sequestration; deforestation; French Guiana; global change; timber stand improvement; tropical forests
Abstract The expansion of selective logging in tropical forests may be an important source of global carbon emissions. However, the effects of logging practices on the carbon cycle have never been quantified over long periods of time. We followed the fate of more than 60 000 tropical trees over 23 years to assess changes in aboveground carbon stocks in 48 1.56-ha plots in French Guiana that represent a gradient of timber harvest intensities, with and without intensive timber stand improvement (TSI) treatments to stimulate timber tree growth. Conventional selective logging led to emissions equivalent to more than a third of aboveground carbon stocks in plots without TSI (85 Mg C/ha), while plots with TSI lost more than one-half of aboveground carbon stocks (142 Mg C/ha). Within 20 years of logging, plots without TSI sequestered aboveground carbon equivalent to more than 80% of aboveground carbon lost to logging (-70.7 Mg C/ha), and our simulations predicted an equilibrium aboveground carbon balance within 45 years of logging. In contrast, plots with intensive TSI are predicted to require more than 100 years to sequester aboveground carbon lost to emissions. These results indicate that in some tropical forests aboveground carbon storage can be recovered within half a century after conventional logging at moderate harvest intensities.
Address [Bonal, Damien; Baraloto, Christopher] INRA, UMR Ecol Forets Guyane, Kourou 97379, French Guiana, Email: chris.baraloto@ecofog.gf
Corporate Author Thesis
Publisher ECOLOGICAL SOC AMER Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-0761 ISBN Medium
Area Expedition Conference
Notes ISI:000269075200003 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 105
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Author Leroy, C.; Corbara, B.; Dejean, A.; Cereghino, R.
Title Ants mediate foliar structure and nitrogen acquisition in a tank-bromeliad Type Journal Article
Year 2009 Publication New Phytologist Abbreviated Journal New Phytol.
Volume 183 Issue 4 Pages 1124-1133
Keywords Aechmea mertensii; antgardens; Camponotus femoratus; foliar structure; delta N-15; Pachycondyla goeldii; phytotelmata contents
Abstract Aechmea mertensii is a tank-bromeliad that roots on ant-gardens initiated by the ants Camponotus femoratus and Pachycondyla goeldii. Its leaves form compartments acting as phytotelmata that hold rainwater and provide habitats for invertebrates. In this article, we aimed to determine whether the association with either C. femoratus or P. goeldii influenced the vegetative traits of A. mertensii, invertebrate diversity and nutrient assimilation by the leaves. Transmitted light, vegetative traits and phytotelmata contents were compared between the two A. mertensii ant-gardens. Camponotus femoratus colonized partially shaded areas, whereas P. goeldii colonized exposed areas. The bromeliads' rosettes had a large canopy (C. femoratus ant-gardens), or were smaller and amphora shaped (P. goeldii ant-gardens). There were significant differences in leaf anatomy, as shaded leaves were thicker than exposed leaves. The mean volumes of water, fine particulate organic matter and detritus in C. femoratus-associated bromeliads were three to five times higher than in P. goeldii-associated bromeliads. Moreover, the highest invertebrate diversity and leaf delta N-15 values were found in C. femoratus-associated bromeliads. This study enhances our understanding of the dynamics of biodiversity, and shows how ant-plant interactions can have trophic consequences and thus influence the architecture of the interacting plant via a complex feedback loop.
Address [Leroy, Celine; Dejean, Alain] EcoFoG, CNRS, UMR 8172, F-97379 Kourou, France, Email: Celine.Leroy@ecofog.gf
Corporate Author Thesis
Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-646X ISBN Medium
Area Expedition Conference
Notes ISI:000268855300020 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 106
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Author Chang, S.S.; Clair, B.; Ruelle, J.; Beauchene, J.; Di Renzo, F.; Quignard, F.; Zhao, G.J.; Yamamoto, H.; Gril, J.
Title Mesoporosity as a new parameter for understanding tension stress generation in trees Type Journal Article
Year 2009 Publication Journal of Experimental Botany Abbreviated Journal J. Exp. Bot.
Volume 60 Issue 11 Pages 3023-3030
Keywords Growth stress; hydrogel; mesoporosity; tension wood
Abstract The mechanism for tree orientation in angiosperms is based on the production of high tensile stress on the upper side of the inclined axis. In many species, the stress level is strongly related to the presence of a peculiar layer, called the G-layer, in the fibre cell wall. The structure of the G-layer has recently been described as a hydrogel thanks to N-2 adsorption-desorption isotherms of supercritically dried samples showing a high mesoporosity (pores size from 2-50 nm). This led us to revisit the concept of the G-layer that had been, until now, only described from anatomical observation. Adsorption isotherms of both normal wood and tension wood have been measured on six tropical species. Measurements show that mesoporosity is high in tension wood with a typical thick G-layer while it is much less with a thinner G-layer, sometimes no more than normal wood. The mesoporosity of tension wood species without a G-layer is as low as in normal wood. Not depending on the amount of pores, the pore size distribution is always centred around 6-12 nm. These results suggest that, among species producing fibres with a G-layer, large structural differences of the G-layer exist between species.
Address [Chang, Shan-Shan; Clair, Bruno; Gril, Joseph] Univ Montpellier 2, LMGC, CNRS, F-34095 Montpellier 5, France, Email: clair@lmgc.univ-montp2.fr
Corporate Author Thesis
Publisher OXFORD UNIV PRESS Place of Publication Editor
Language Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-0957 ISBN Medium
Area Expedition Conference
Notes ISI:000268588300008 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 107
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