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Author Jabiol, J.; Corbara, B.; Dejean, A.; Cereghino, R. openurl 
  Title Structure of aquatic insect communities in tank-bromeliads in a East-Amazonian rainforest in French Guiana Type Journal Article
  Year 2009 Publication Forest Ecology and Management Abbreviated Journal For. Ecol. Manage.  
  Volume 257 Issue 1 Pages 351-360  
  Keywords Bromeliaceae; Classification; Community structure; Insects; Microcosms; Neural networks; Nouragues; Phytotelmata; Species richness  
  Abstract Tank-bromeliads are discrete habitats which contain distinct aquatic communities, and which commonly occur in the neotropics. Because they span a broad range of ecological gradients in terms of habitat structure and amount of resources, researchers study the associations between the biodiversity of communities and these gradients in rainforests, where the very high species richness and densities within other continuous habitats makes it difficult to quantify animal communities. We analysed the diversity of aquatic insect communities in relation to different tank-bromeliad species in a primary rainforest (French Guiana) using artificial intelligence and complex optimization techniques to classify communities and model their determinants. First, the self-organizing map (neural network) was used to classify 158 bromeliads according to the quantitative structure of the insect communities. Catopsis berteroniana and Guzmania lingulata formed separate clusters of plants on the virtual map, while Vriesea splendens, Vriesea pleiosticha and Aechmea melinonii were grouped together in the remaining clusters. Some insect taxa occurred in all bromeliads, while other taxa were specific to a given species. Second, general linear modelling allowed us to specify the influence of the bromeliad species; water volume and volume of fine particulate organic matter inside of the tank; elevation above the ground; and sampling site on taxonomic richness and insect abundance. The number of taxa and individuals per plant increased with greater water volume, but the slope of the relationships depended on the bromeliad species. The significant influence of bromeliad species suggested that at similar water volumes different plant species had different taxon richness and insect abundance. Greater amounts of fine particulate organic matter were detrimental to community diversity in the tanks, probably because they decreased available space by clogging it and/or affected oxygen concentrations. The influence of tank-bromeliad species on the aquatic insect community was primarily related to their physical (and probably chemical) features rather than to species-specific associations sensu stricto. The classification of bromeliads with respect to animal species is likely to provide referential schemes for those biodiversity patterns to be expected under certain conditions, and may help to target model communities for subsequent experimental research. (C) 2008 Elsevier B,V. All rights reserved.  
  Address (down) [Jabiol, J.; Cereghino, R.] Univ Toulouse 3, Ecolab, Lab Ecol Fonctionnelle, CNRS,UMR 5245, F-31062 Toulouse 9, France, Email: cereghin@cict.fr  
  Corporate Author Thesis  
  Publisher ELSEVIER SCIENCE BV Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-1127 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000261856000038 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 124  
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Author Coste, S.; Baraloto, C.; Leroy, C.; Marcon, E.; Renaud, A.; Richardson, A.D.; Roggy, J.C.; Schimann, H.; Uddling, J.; Herault, B. openurl 
  Title Assessing foliar chlorophyll contents with the SPAD-502 chlorophyll meter: a calibration test with thirteen tree species of tropical rainforest in French Guiana Type Journal Article
  Year 2010 Publication Annals of Forest Science Abbreviated Journal Ann. For. Sci.  
  Volume 67 Issue 6 Pages 607  
  Keywords chlorophyll estimate; model calibration; homographic functions; neotropical trees  
  Abstract Chlorophyll meters such as the SPAD-502 offer a simple, inexpensive and rapid method to estimate foliar chlorophyll content. However, values provided by SPAD-502 are unitless and require empirical calibrations between SPAD units and extracted chlorophyll values. Leaves of 13 tree species from the tropical rain forest in French Guiana were sampled to select the most appropriate calibration model among the often-used linear, polynomial and exponential models, in addition to a novel homographic model that has a natural asymptote. The homographic model best accurately predicted total chlorophyll content (mu g cm(-2)) from SPAD units (R-2 = 0.89). Interspecific differences in the homographic model parameters explain less than 7% of the variation in chlorophyll content in our data set. The utility of the general homographic model for a variety of research and management applications clearly outweighs the slight loss of model accuracy due to the abandon of the species' effect.  
  Address (down) [Herault, Bruno] Univ Antilles Guyane, Unite Mixte Rech Ecol Forets Guyane, Kourou, France, Email: bruno.herault@ecofog.gf  
  Corporate Author Thesis  
  Publisher EDP SCIENCES S A Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1286-4560 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000282350300007 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 40  
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Author Herault, B.; Ouallet, J.; Blanc, L.; Wagner, F.; Baraloto, C. openurl 
  Title Growth responses of neotropical trees to logging gaps Type Journal Article
  Year 2010 Publication Journal of Applied Ecology Abbreviated Journal J. Appl. Ecol.  
  Volume 47 Issue 4 Pages 821-831  
  Keywords canopy openings; functional traits; incidence function model; light partitioning; selective logging; tree growth rates; tropical rain forest  
  Abstract P>1. Modelling growth strategies among tropical trees is an important objective in predicting the response of tree dynamics to selective logging and in gaining insights into the ecological processes that structure tree communities in managed tropical forests. 2. We developed a disturbance index to model the effects of distance to and area of logging gaps on stem radial growth rates. This index was tested using census data of 43 neotropical tree species, representing a variety of life-history strategies and developmental stages, from a selectively logged forest at Paracou, French Guiana. Growth strategies were analyzed in light of two indicators: the inherent species growth rate (when disturbance index is null) and the species reaction (change in growth rate) to logging gaps. 3. Across species, the predicted inherent growth rates in unlogged forest ranged from 0 center dot 25 to 6 center dot 47 mm year-1, with an average growth of 2 center dot 29 mm year-1. Ontogenetic shifts in inherent growth rate were found in 26 of the 43 species. 4. Species growth response to logging gaps varied widely among species but was significantly positive for 27 species. The effect of ontogeny on growth response to logging was retained for 14 species, and species with inherent fast growth rate (5 mm year-1) responded less to logging gap disturbances than did species with slow inherent growth (1 mm year-1). 5. Functional traits explained 19-42% of the variation in the inherent growth rate and in species' response across all developmental stages. Whereas maximum diameters and seed mass were strong predictors of inherent growth rate, maximum height, wood density, mode of germination and stem architecture were additionally involved in tree growth response. 6. Synthesis and applications: This study provides a necessary framework for developing predictive post-logging growth models for the thousands of species comprising tropical forests and is sufficiently general to apply to a broad range of managed tropical forests.  
  Address (down) [Herault, Bruno] Univ Antilles Guyane, UMR Ecol Forets Guyane, F-97387 Kourou, France, Email: bruno.herault@ecofog.gf  
  Corporate Author Thesis  
  Publisher WILEY-BLACKWELL PUBLISHING, INC Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8901 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000279405100012 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 53  
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Author Herault, B. openurl 
  Title Reconciling niche and neutrality through the Emergent Group approach Type Journal Article
  Year 2007 Publication Perspectives in Plant Ecology Evolution and Systematics Abbreviated Journal Perspect. Plant Ecol. Evol. Syst.  
  Volume 9 Issue 2 Pages 71-78  
  Keywords Biodiversity; ecological equivalency; biological traits; neutral theory; niche differentiation; redundancy  
  Abstract Both niche and neutral theories have been suggested as potential frameworks for modelling biodiversity. Niche models assume that biological traits represent evolutionary adaptations and define individuals in terms of functional trade-offs. Neutral models assume that all individuals at a single trophic level are functionally equivalent on a per capita basis with respect to their birth, death, dispersal and speciation. The opinion of many researchers is that neutral and niche processes operate simultaneously to generate diversity without knowing how the unification of both models can be achieved. Recently, several theoretical papers have reported evidence on the evolutionary emergence of niche structures shaping the emergence of groups of similar species. In this way, an Emergent Group is defined as a set of species that have a similar functional niche owing to a convergent ecological strategy. Central to the Emergent Group concept are the assumptions of functional equivalence within and of functional divergence between Emergent Groups. Within an Emergent Group, species richness is subject to a zero-sum rule set by the balance between the rate of individual loss and of immigration. Between Emergent Groups, tradeoffs such as seed size/seedling competitivity, investment in reproductive system/investment in vegetative systems or competitive ability/predator invulnerability are cornerstones of the evolutionary divergence. Delineating Emergent Groups amounts to reaching a compromise between maximizing niche differentiation (i.e. maximizing differences in functional tradeoffs) between Emergent Groups and maximizing neutrality within Emergent Groups. Up to now, the Emergent Group concept has been mostly proposed by theoretical scientists but it should be tested by empirical ecologists. The way in which niche and neutral models could be combined provides a profitable opportunity for theoretical and empirical scientists to collaborate fruitfully. (c) 2007 Rubel Foundation, ETH Zurich. Published by Elsevier GmbH. All rights reserved.  
  Address (down) [Herault, Bruno] Univ Antilles Guyane, UMR Ecol Forets Guyane, F-97379 Kourou, France, Email: Bruno.Herault@cirad.fr  
  Corporate Author Thesis  
  Publisher ELSEVIER GMBH, URBAN & FISCHER VERLAG Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1433-8319 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000251685100002 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 147  
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Author Herault, B.; Thoen, D. openurl 
  Title How habitat area, local and regional factors shape plant assemblages in isolated closed depressions Type Journal Article
  Year 2009 Publication Acta Oecologica-International Journal of Ecology Abbreviated Journal Acta Oecol.-Int. J. Ecol.  
  Volume 35 Issue 3 Pages 385-392  
  Keywords Closed depressions; Colonization; Connectivity; Fragmented habitats; Emergent Groups; Open and forested landscape; Life-history traits  
  Abstract Classifying species by shared life-history traits is important if common ecological response groups are to be identified among different species. We investigated how habitat area, local and regional factors shape plant communities in small isolated closed depressions, and how the species richness is related to the interplay between environmental factors and specific life-history trait combinations. In Central-Western Europe, 169 closed depressions were completely Surveyed for plant presence in two highly contrasted landscapes (forested and open landscapes). All species were clustered into 9 Emergent Groups based oil 10 life-history traits related to plant dispersal, establishment and persistence. Habitat areas were related to species presence using logistic regressions. Most Emergent Groups were more area-dependent in open than in forested landscapes, owing to heterogeneous light levels in forest weakening the species-area relationship. In open landscapes, Floating Hydrophytes were severely underrepresented in very small depressions, owing to the absence of waterfowl poulation. Local environmental and regional factors were related to species richness using Generalized Linear Models. In open landscapes, local environmental factors such as water conductivity or soil productivity are respectively the main predictors. In forested landscapes, the abundance of most Emergent Groups Was better predicted by regional factors, i.e., habitat connectivity and distance to the forest edge. Forested landscapes strongly impeded the closed depressions' colonization by the less mobile Emergent Groups Such as Large-seeded Perennials. (C) 2009 Elsevier Masson SAS. All rights reserved.  
  Address (down) [Herault, Bruno] Univ Antilles Guyane, UMR EcoFoG, F-97387 Kourou, France, Email: bruno.herault@ecofog.gf  
  Corporate Author Thesis  
  Publisher GAUTHIER-VILLARS/EDITIONS ELSEVIER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1146-609X ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000266174400006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 112  
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Author Herault, B.; Bornet, A.; Tremolieres, M. openurl 
  Title Redundancy and niche differentiation among the European invasive Elodea species Type Journal Article
  Year 2008 Publication Biological Invasions Abbreviated Journal Biol. Invasions  
  Volume 10 Issue 7 Pages 1099-1107  
  Keywords biological traits; functional equivalence; invasivness; niche overlapping; waterweeds  
  Abstract Community ecologists implicitly assume redundancy when they aggregate species into functional groups. But there have been remarkably few empirical efforts to investigate the accuracy of this concept in situ. The concept of redundancy could be roughly split into two components: the ecological redundancy (similar response to environmental variations involving similar ecological processes) and the functional redundancy (similar biological trait combinations shaping similar functional processes). Both types of redundancy are tested among the 3 invasive European Elodeas. In 11 sites and during two successive years 2004-2005, the cover growth rate of each Elodea species was monthly recorded. To test ecological redundancy, cover growth rates were related to a large suite of environmental variables. To test functional redundancy, 13 biological traits involved in competitive relationships were measured each month. Firstly, the redundancy hypothesis looks problematic for Elodea ernstiae. Indeed, the later possess numerous biological traits involved in light competition and niche overlap with the other Elodeas is very low. Secondly, ecological and functional redundancy can be successfully applied to Elodea canadensis and Elodea nuttallii. They share a large suite of biological traits leading to wide niche overlaps through the growing season. And the measured environmental variables do not differentially influence their growth rates, which are, in turn, controlled by a similar group of biological traits. In this way, the different invasiveness patterns of E. canadensis and E. nuttallii could be solely due to the ecological drift and their ecological dynamic could follow neutral rules.  
  Address (down) [Herault, Bruno] Univ Antilles Guyane, INRA, UMR Ecol Forets Guyane, F-97379 Kourou, France, Email: Bruno.Herault@cirad.fr  
  Corporate Author Thesis  
  Publisher SPRINGER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1387-3547 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000258704400015 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 131  
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Author Herault, B.; Thoen, D. openurl 
  Title Diversity of plant assemblages in isolated depressional wetlands from Central-Western Europe Type Journal Article
  Year 2008 Publication Biodiversity and Conservation Abbreviated Journal Biodivers. Conserv.  
  Volume 17 Issue 9 Pages 2169-2183  
  Keywords closed depressions; connectivity; fens; forest; grassland; habitat area; landscape matrix  
  Abstract A closed depression is defined as a geomorphologic element where a sediment depository is encircled by hillslopes. Despite the fact that closed depressions are often the only stagnant water points in many European landscapes, few ecological researches on their plant assemblages have been done. The main goal of this study was to give first results of the environmental factors responsible for the vegetation composition, richness and rarity in the closed depressions of the Lorraine biogeographical district (Belgium, France and grand-duche de Luxembourg). We surveyed for plant presence 85 forest and 77 grassland closed depressions. For each site, wetland area, local environmental factors and regional connectivities registered. For each species, the Ellenberg values were compiled. To investigate the main source of variation in species composition and in species richness (including richness in rare species), Non-metric Multidimensional Scaling analyses and Generalized Linear Models were respectively used. Species pools in forest (forest and preforest species) and in grassland (bog plants, pioneers, helophytes) were quite different. In both landscapes, a gradient from plants typical of basic high-productive soils to plants typical of acid low-productive soils reflects a shared successional gradient. The accumulation of organic matter allowed the establishment of Sphagnum spp., which slowly acidified the soil and thus acted as ecosystem engineers for the arrival of bog plants. Moreover, the species composition was additionally driven by the plant light tolerance in forests and by the plant water requirements in grasslands. Mechanisms of species accumulation (increase in species richness) were different in forests and in grasslands: respectively related to the plant light tolerance and to the wetland area. At the regional level, the averaged soil productivity was negatively related to the richness in rare species. Indeed, perennial highly-competitive plants such as Glyceria spp., Iris pseudacorus or Urtica dioica impeded the establishment of smaller and rarer species. At the habitat level, isolated closed depressions (due to either low connectivity or low grazing pressure) have more habitat rare species, giving evidences of dispersal limitation in plant assemblages of closed depressions.  
  Address (down) [Herault, Bruno] Inst Bot, Ctr Ecol Vegetale & Hydrol, F-67083 Strasbourg, France, Email: bruno.herault@cirad.fr  
  Corporate Author Thesis  
  Publisher SPRINGER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0960-3115 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000257486400008 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 135  
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Author Herault, B.; Beauchene, J.; Muller, F.; Wagner, F.; Baraloto, C.; Blanc, L.; Martin, J.M. openurl 
  Title Modeling decay rates of dead wood in a neotropical forest Type Journal Article
  Year 2010 Publication Oecologia Abbreviated Journal Oecologia  
  Volume 164 Issue 1 Pages 243-251  
  Keywords Amazonia; Carbon cycle; Decomposition; Selective logging; Rainforest; Coarse woody debris  
  Abstract Variation of dead wood decay rates among tropical trees remains one source of uncertainty in global models of the carbon cycle. Taking advantage of a broad forest plot network surveyed for tree mortality over a 23-year period, we measured the remaining fraction of boles from 367 dead trees from 26 neotropical species widely varying in wood density (0.23-1.24 g cm(-3)) and tree circumference at death time (31.5-272.0 cm). We modeled decay rates within a Bayesian framework assuming a first order differential equation to model the decomposition process and tested for the effects of forest management (selective logging vs. unexploited), of mode of death (standing vs. downed) and of topographical levels (bottomlands vs. hillsides vs. hilltops) on wood decay rates. The general decay model predicts the observed remaining fraction of dead wood (R (2) = 60%) with only two biological predictors: tree circumference at death time and wood specific density. Neither selective logging nor local topography had a differential effect on wood decay rates. Including the mode of death into the model revealed that standing dead trees decomposed faster than downed dead trees, but the gain of model accuracy remains rather marginal. Overall, these results suggest that the release of carbon from tropical dead trees to the atmosphere can be simply estimated using tree circumference at death time and wood density.  
  Address (down) [Herault, Bruno; Wagner, Fabien; Martin, Jean-Michel] Univ Antilles Guyane, UMR EcoFoG, F-97387 Kourou, France, Email: bruno.herault@ecofog.gf  
  Corporate Author Thesis  
  Publisher SPRINGER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0029-8549 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000280962200023 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 45  
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Author Hattenschwiler, S.; Fromin, N.; Barantal, S. openurl 
  Title Functional diversity of terrestrial microbial decomposers and their substrates Type Journal Article
  Year 2011 Publication Comptes Rendus Biologies Abbreviated Journal C. R. Biol.  
  Volume 334 Issue 5-6 Pages 393-402  
  Keywords Bacteria; Biogeochemical cycles; Decomposition; Dissimilarity; Ecosystem functioning; Functional diversity indices; Fungi; Leaf litter  
  Abstract The relationship between biodiversity and biogeochemical processes gained much interest in light of the rapidly decreasing biodiversity worldwide. In this article, we discuss the current status, challenges and prospects of functional concepts to plant litter diversity and microbial decomposer diversity. We also evaluate whether these concepts permit a better understanding of how biodiversity is linked to litter decomposition as a key ecosystem process influencing carbon and nutrient cycles. Based on a literature survey, we show that plant litter and microbial diversity matters for decomposition, but that considering numbers of taxonomic units appears overall as little relevant and less useful than functional diversity. However, despite easily available functional litter traits and the well-established theoretical framework for functional litter diversity, the impact of functional litter diversity on decomposition is not yet well enough explored. Defining functional diversity of microorganisms remains one of the biggest challenges for functional approaches to microbial diversity. Recent developments in microarray and metagenomics technology offer promising possibilities in the assessment of the functional structure of microbial communities. This might allow significant progress in measuring functional microbial diversity and ultimately in our ability to predict consequences of biodiversity loss in the decomposer system for biogeochemical processes. (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.  
  Address (down) [Haettenschwiler, Stephan; Fromin, Nathalie; Barantal, Sandra] CNRS, CEFE, F-34293 Montpellier 5, France, Email: stephan.hattenschwiler@cefe.cnrs.fr  
  Corporate Author Thesis  
  Publisher Elsevier France-Editions Scientifiques Medicales Elsevier Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1631-0691 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000292013400008 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 323  
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Author Haettenschwiler, S.; Coq, S.; Barantal, S.; Handa, I.T. openurl 
  Title Leaf traits and decomposition in tropical rainforests: revisiting some commonly held views and towards a new hypothesis Type Journal Article
  Year 2011 Publication New Phytologist Abbreviated Journal New Phytol.  
  Volume 189 Issue 4 Pages 950-965  
  Keywords energy starvation; French Guiana; litter quality; mycorrhizas; nutrient cycling; nutrient limitation; phosphorus; soil fauna  
  Abstract Proper estimates of decomposition are essential for tropical forests, given their key role in the global carbon (C) cycle. However, the current paradigm for litter decomposition is insufficient to account for recent observations and may limit model predictions for highly diverse tropical ecosystems. In light of recent findings from a nutrient-poor Amazonian rainforest, we revisit the commonly held views that: litter traits are a mere legacy of live leaf traits; nitrogen (N) and lignin are the key litter traits controlling decomposition; and favourable climatic conditions result in rapid decomposition in tropical forests. Substantial interspecific variation in litter phosphorus (P) was found to be unrelated to variation in green leaves. Litter nutrients explained no variation in decomposition, which instead was controlled primarily by nonlignin litter C compounds at low concentrations with important soil fauna effects. Despite near-optimal climatic conditions, tropical litter decomposition proceeded more slowly than in a climatically less favourable temperate forest. We suggest that slow decomposition in the studied rainforest results from a syndrome of poor litter C quality beyond a simple lignin control, enforcing energy starvation of decomposers. We hypothesize that the litter trait syndrome in nutrient-poor tropical rainforests may have evolved to increase plant access to limiting nutrients via mycorrhizal associations.  
  Address (down) [Haettenschwiler, Stephan; Coq, Sylvain; Barantal, Sandra; Handa, Ira Tanya] CNRS, CEFE, F-34293 Montpellier 5, France, Email: stephan.hattenschwiler@cefe.cnrs.fr  
  Corporate Author Thesis  
  Publisher Wiley-Blackwell Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-646x ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000286940500009 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 296  
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