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Author Lehours, A.-C.; Jeune, A.-H.L.; Aguer, J.-P.; Céréghino, R.; Corbara, B.; Kéraval, B.; Leroy, C.; Perrière, F.; Jeanthon, C.; Carrias, J.-F.
Title Unexpectedly high bacteriochlorophyll a concentrations in neotropical tank bromeliads Type Journal Article
Year 2016 Publication Environmental Microbiology Reports Abbreviated Journal Environmental Microbiology Reports
Volume 8 Issue 5 Pages 689-698
Keywords
Abstract The contribution of bacteriochlorophyll a (BChl a) to photosynthetically driven electron transport is generally low in aquatic and terrestrial systems. Here, we provide evidence that anoxygenic bacterial phototrophy is widespread and substantial in water retained by tank bromeliads of a primary rainforest in French Guiana. An analysis of the water extracted from 104 randomly selected tank bromeliads using infrared fluorimetry suggested the overall presence of abundant anoxygenic phototrophic bacterial populations. We found that purple bacteria dominated these populations responsible for unusually high BChl a/chlorophyll a ratios (>50%). Our data suggest that BChl a-based phototrophy in tank bromeliads can have significant effects on the ecology of tank-bromeliad ecosystems and on the carbon and energy fluxes in Neotropical forests.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1758-2229 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 709
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Author Malé, P.-J.G.; Leroy, C.; Humblot, P.; Dejean, A.; Quilichini, A.; Orivel, J.
Title Limited gene dispersal and spatial genetic structure as stabilizing factors in an ant-plant mutualism Type Journal Article
Year 2016 Publication Journal of Evolutionary Biology Abbreviated Journal J. Evol. Biol.
Volume 29 Issue 12 Pages 2519-2529
Keywords gene flow; local adaptation; metapopulation; myrmecophyte; population genetics
Abstract Comparative studies of the population genetics of closely associated species are necessary to properly understand the evolution of these relationships because gene flow between populations affects the partners' evolutionary potential at the local scale. As a consequence (at least for antagonistic interactions), asymmetries in the strength of the genetic structures of the partner populations can result in one partner having a co-evolutionary advantage. Here, we assess the population genetic structure of partners engaged in a species-specific and obligatory mutualism: the Neotropical ant-plant, Hirtella physophora, and its ant associate, Allomerus decemarticulatus. Although the ant cannot complete its life cycle elsewhere than on H. physophora and the plant cannot live for long without the protection provided by A. decemarticulatus, these species also have antagonistic interactions: the ants have been shown to benefit from castrating their host plant and the plant is able to retaliate against too virulent ant colonies. We found similar short dispersal distances for both partners, resulting in the local transmission of the association and, thus, inbred populations in which too virulent castrating ants face the risk of local extinction due to the absence of H. physophora offspring. On the other hand, we show that the plant populations probably experienced greater gene flow than did the ant populations, thus enhancing the evolutionary potential of the plants. We conclude that such levels of spatial structure in the partners' populations can increase the stability of the mutualistic relationship. Indeed, the local transmission of the association enables partial alignments of the partners' interests, and population connectivity allows the plant retaliation mechanisms to be locally adapted to the castration behaviour of their symbionts.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1420-9101 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 710
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Author Leroy, C.; Petitclerc, F.; Orivel, J.; Corbara, B.; Carrias, J.-F.; Dejean, A.; Céréghino, R.
Title The influence of light, substrate and seed origin on the germination and establishment of an ant-garden bromeliad Type Journal Article
Year 2017 Publication Plant Biology Abbreviated Journal Plant Biol J
Volume 19 Issue 1 Pages 70-78
Keywords Aechmea mertensii; bromeliad; French Guiana; germination; plant performance; survival
Abstract Plant germination and development depend upon a seed's successful dispersal into a suitable habitat and its ability to grow and survive within the surrounding biotic and abiotic environment. The seeds of Aechmea mertensii, a tank-bromeliad species, are dispersed by either Camponotus femoratus or Neoponera goeldii, two ant species that initiate ant gardens (AGs). These two mutualistic ant species influence the vegetative and reproductive traits of the bromeliad through their divergent ecological preferences (i.e. light and substrate). We hypothesised that the seeds dispersed by these two ant species have underlying genetic differences affecting germination, growth and survival of A. mertensii seedlings in different ways. To test this, we used an experimental approach consisting of sowing seeds of A. mertensii: (i) taken from the two AG–ant associations (i.e. seed origin), (ii) in two contrasting light conditions, and (iii) on three different substrates. Light and substrate had significant effects on germination, survival and on eight key leaf traits reflecting plant performance. Seed origin had a significant effect only on germination and on two leaf traits (total dry mass and relative growth rate). Overall, this bromeliad performs better (i.e. high growth and survival rates) when growing both in the shade and in the carton nest developed by C. femoratus ants. These results suggest that the plasticity of the tank bromeliad A. mertensii is mainly due to environment but also to genetic differences related to seed origin, as some traits are heritable. Thus, these two ant species may play contrasting roles in shaping plant evolution and speciation.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1438-8677 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 712
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Author Courtois, E.A.; Dexter, K.G.; Paine, C.E.T.; Stien, D.; Engel, J.; Baraloto, C.; Chave, J.
Title Evolutionary patterns of volatile terpene emissions across 202 tropical tree species Type Journal Article
Year 2016 Publication Ecology and Evolution Abbreviated Journal Ecol Evol
Volume 6 Issue 9 Pages 2854-2864
Keywords Chemical defense; French Guiana; herbivory; secondary metabolites; tropical forest
Abstract Plant responses to natural enemies include formation of secondary metabolites acting as direct or indirect defenses. Volatile terpenes represent one of the most diverse groups of secondary metabolites. We aimed to explore evolutionary patterns of volatile terpene emission. We measured the composition of damage-induced volatile terpenes from 202 Amazonian tree species, spanning the angiosperm phylogeny. Volatile terpenes were extracted with solid-phase micro extraction and desorbed in a gas chromatography–mass spectrometry for compound identification. The chemical diversity of the terpene blend showed a strong phylogenetic signal as closely related species emitted a similar number of compounds. Closely related species also tended to have compositionally similar blends, although this relationship was weak. Meanwhile, the ability to emit a given compound showed no significant phylogenetic signal for 200 of 286 compounds, indicating a high rate of diversification in terpene synthesis and/or great variability in their expression. Three lineages (Magnoliales, Laurales, and Sapindales) showed exceptionally high rates of terpene diversification. Of the 70 compounds found in >10% of their species, 69 displayed significant correlated evolution with at least one other compound. These results provide insights into the complex evolutionary history of volatile terpenes in angiosperms, while highlighting the need for further research into this important class of compounds.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-7758 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 713
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Author Denis, T.; Herault, B.; Jaouen, G.; Brunaux, O.; Guitet, S.; Richard-Hansen, C.
Title Black Curassow habitat relationships in terra firme forests of the Guiana Shield: A multiscale approach Type Journal Article
Year 2016 Publication The Condor Abbreviated Journal The Condor
Volume 118 Issue 2 Pages 253-273
Keywords
Abstract ABSTRACT The Black Curassow (Crax alector) is a large game bird with Vulnerable conservation status found in north-central South America. We examined its distributional pattern across French Guiana using a large number of environmental descriptors at 3 scales of analysis: landscape, forest type, and microhabitat. We used a hierarchical model with temporary emigration and imperfect detection for data collected by standard distance sampling methods at 35 study sites. At the landscape scale, Black Curassow density decreased with hunting pressure and increased with steeper slopes in both hunted and unhunted areas. Topography appeared to be a good proxy for Black Curassow ecological requirements and probably reflected habitat quality. At the forest scale, population density was negatively correlated with the abundance of palms and Mimosoideae and positively correlated with the abundance of Lauraceae. Botanical families did not directly influence Black Curassow distribution, but rather determined spatial patterns by being markers of a particular forest type. At the microhabitat scale, Black Curassows used hilltops more frequently than other parts of the local topographical gradient. Our multiscale analysis shows that this species' distribution can be explained by biotic or abiotic conditions, regardless of the scale. For conservation, we recommend maintaining connectivity between Black Curassow populations separated by hunted areas. Our predicted densities could be used to adapt hunting quotas across French Guiana's forests. We show that combining field and remote sensing data helps to understand the ecological processes responsible for Black Curassow habitat relationships.
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Publisher American Ornithological Society Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0010-5422 ISBN Medium
Area Expedition Conference
Notes doi: 10.1650/CONDOR-15-28.1 Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 714
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Author Ghislain, B.; Nicolini, E.-A.; Romain, R.; Ruelle, J.; Yoshinaga, A.; Alford, M.H.; Clair, B.
Title Multilayered structure of tension wood cell walls in Salicaceae sensu lato and its taxonomic significance Type Journal Article
Year 2016 Publication Botanical Journal of the Linnean Society Abbreviated Journal Bot. J. Linn. Soc.
Volume 182 Issue 4 Pages 744-756
Keywords Flacourtiaceae; G-layer; multilayered tension wood; reaction wood
Abstract Salicaceae have been enlarged to include a majority of the species formerly placed in the polyphyletic tropical Flacourtiaceae. Several studies have reported a peculiar and infrequently formed multilayered structure of tension wood in four of the tropical genera. Tension wood is a tissue produced by trees to restore their vertical orientation and most studies have focused on trees developing tension wood by means of cellulose-rich, gelatinous fibres, as in Populus and Salix (Salicaceae s.s.). This study aims to determine if the multilayered structure of tension wood is an anatomical characteristic common in other Salicaceae and, if so, how its distribution correlates to phylogenetic relationships. Therefore, we studied the tension wood of 14 genera of Salicaceae and two genera of Achariaceae, one genus of Goupiaceae and one genus of Lacistemataceae, families closely related to Salicaceae or formerly placed in Flacourtiaceae. Opposite wood and tension wood were compared with light microscopy and three-dimensional laser scanning confocal microscopy. The results indicate that a multilayered structure of tension wood is common in the family except in Salix, Populus and one of their closest relatives, Idesia polycarpa. We suggest that tension wood may be a useful anatomical character in understanding phylogenetic relationships in Salicaceae. Further investigation is still needed on the tension wood of several other putatively close relatives of Salix and Populus, in particular Bennettiodendron, Macrohasseltia and Itoa.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1095-8339 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 718
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Author Alméras, T.; Clair, B.
Title Critical review on the mechanisms of maturation stress generation in trees Type Journal Article
Year 2016 Publication Journal of the Royal Society Interface Abbreviated Journal J R Soc Interface
Volume 13 Issue 122 Pages
Keywords
Abstract Trees control their posture by generating asymmetric mechanical stress around the periphery of the trunk or branches. This stress is produced in wood during the maturation of the cell wall. When the need for reaction is high, it is accompanied by strong changes in cell organization and composition called reaction wood, namely compression wood in gymnosperms and tension wood in angiosperms. The process by which stress is generated in the cell wall during its formation is not yet known, and various hypothetical mechanisms have been proposed in the literature. Here we aim at discriminating between these models. First, we summarize current knowledge about reaction wood structure, state and behaviour relevant to the understanding of maturation stress generation. Then, the mechanisms proposed in the literature are listed and discussed in order to identify which can be rejected based on their inconsistency with current knowledge at the frontier between plant science and mechanical engineering.
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Notes Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 719
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Author Morel-Journel, T.; Piponiot, C.; Vercken, E.; Mailleret, L.
Title Evidence for an optimal level of connectivity for establishment and colonization Type Journal Article
Year 2016 Publication Biology Letters Abbreviated Journal Biol Lett
Volume 12 Issue 11 Pages 20160704
Keywords
Abstract Dispersal is usually associated with the spread of invasive species, but it also has two opposing effects, one decreasing and the other increasing the probability of establishment. Indeed, dispersal both slows population growth at the site of introduction and increases the likelihood of surrounding habitat being colonized. The connectivity of the introduction site is likely to affect dispersal, and, thus, establishment, according to the dispersal behaviour of individuals. Using individual-based models and microcosm experiments on minute wasps, we demonstrated the existence of a hump-shaped relationship between connectivity and establishment in situations in which individual dispersal resembled a diffusion process. These results suggest that there is an optimal level of connectivity for the establishment of introduced populations locally at the site of introduction, and regionally over the whole landscape.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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Area Expedition Conference
Notes Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 722
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Author Rutishauser, E.; Herault, B.; Petronelli, P.; Sist, P.
Title Tree Height Reduction After Selective Logging in a Tropical Forest Type Journal Article
Year 2016 Publication Biotropica Abbreviated Journal Biotropica
Volume 48 Issue 3 Pages 285-289
Keywords carbon sequestration; forest management; logging; tropical forests; wood production
Abstract By harvesting scattered large trees, selective logging increases light availability and thereby stimulates growth and crown expansion at early-life stage among remnant trees. We assessed the effects of logging on total and merchantable bole (i.e., lowest branch at crown base) heights on 952 tropical canopy trees in French Guiana. We observed reductions in both total (mean, −2.3 m) and bole (mean, −2.0 m) heights more than a decade after selective logging. Depending on local logging intensity, height reductions resulted in 2–13 percent decreases in aboveground tree biomass and 3–17 percent decreases in bole volume. These results highlight the adverse effects of logging at both tree and stand levels. This decrease in height is a further threat to future provision of key environmental services, such as timber production and carbon sequestration.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1744-7429 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 723
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Author Goulamoussene, Youven; Bedeau, Caroline; Descroix, Laurent; Deblauwe, Vincent; Linguet, Laurent; Herault, Bruno
Title Weak Environmental Controls of Tropical Forest Canopy Height in the Guiana Shield Remote Sensing Type Journal Article
Year 2016 Publication Remote Sensing Abbreviated Journal Remote Sens
Volume 8 Issue 9 Pages 747
Keywords
Abstract Canopy height is a key variable in tropical forest functioning and for regional carbon inventories. We investigate the spatial structure of the canopy height of a tropical forest, its relationship with environmental physical covariates, and the implication for tropical forest height variation mapping. Making use of high-resolution maps of LiDAR-derived Digital Canopy Model (DCM) and environmental covariates from a Digital Elevation Model (DEM) acquired over 30,000 ha of tropical forest in French Guiana, we first show that forest canopy height is spatially correlated up to 2500 m. Forest canopy height is significantly associated with environmental variables, but the degree of correlation varies strongly with pixel resolution. On the whole, bottomland forests generally have lower canopy heights than hillslope or hilltop forests. However, this global picture is very noisy at local scale likely because of the endogenous gap-phase forest dynamic processes. Forest canopy height has been predictively mapped across a pixel resolution going from 6 m to 384 m mimicking a low resolution case of 3 points·km − 2 . Results of canopy height mapping indicated that the error for spatial model with environment effects decrease from 8.7 m to 0.91 m, depending of the pixel resolution. Results suggest that, outside the calibration plots, the contribution of environment in shaping the global canopy height distribution is quite limited. This prevents accurate canopy height mapping based only on environmental information, and suggests that precise canopy height maps, for local management purposes, can only be obtained with direct LiDAR monitoring.
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Language Summary Language Original Title
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Notes Approved no
Call Number (up) EcoFoG @ webmaster @ Serial 724
Permanent link to this record