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Author Houadria, M.; Blüthgen, N.; Salas-Lopez, A.; Schmitt, M.-I.; Arndt, J.; Schneider, E.; Orivel, J.; Menzel, F. url  openurl
  Title The relation between circadian asynchrony, functional redundancy, and trophic performance in tropical ant communities Type Journal Article
  Year 2016 Publication Ecology Abbreviated Journal (down) Ecology  
  Volume 97 Issue 1 Pages 225-235  
  Keywords Diel turnover; Ecosystem functioning; Functional diversity; Multifunctional redundancy; Sampling effect; Temporal partitioning; Tropical rain forests  
  Abstract The diversity-stability relationship has been under intense scrutiny for the past decades, and temporal asynchrony is recognized as an important aspect of ecosystem stability. In contrast to relatively well- studied interannual and seasonal asynchrony, few studies investigate the role of circadian cycles for ecosystem stability. Here, we studied multifunctional redundancy of diurnal and nocturnal ant communities in four tropical rain forest sites. We analyzed how it was influenced by species richness, functional performance, and circadian asynchrony. In two neotropical sites, species richness and functional redundancy were lower at night. In contrast, these parameters did not differ in the two paleotropical sites we studied. Circadian asynchrony between species was pronounced in the neotropical sites, and increased circadian functional redundancy. In general, species richness positively affected functional redundancy, but the effect size depended on the temporal and spatial breadth of the species with highest functional performance. Our analysis shows that high levels of trophic performance were only reached through the presence of such high- performing species, but not by even contributions of multiple, less- efficient species. Thus, these species can increase current functional performance, but reduce overall functional redundancy. Our study highlights that diurnal and nocturnal ecosystem properties of the very same habitat can markedly differ in terms of species richness and functional redundancy. Consequently, like the need to study multiple ecosystem functions, multiple periods of the circadian cycle need to be assessed in order to fully understand the diversity- stability relationship in an ecosystem. © 2016 by the Ecological Society of America.  
  Address CNRS, UMR Ecologie des Forêts de Guyane, BP 709, Kourou Cedex, France  
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  Notes Export Date: 17 February 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 664  
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Author Falster, D.S.; Duursma, R.A.; Ishihara, M.I.; Barneche, D.R.; FitzJohn, R.G.; Vårhammar, A.; Aiba, M.; Ando, M.; Anten, N.; Aspinwall, M.J.; Baltzer, J.L.; Baraloto, C.; Battaglia, M.; Battles, J.J.; Lamberty, B.B.; Van Breugel, M.; Camac, J.; Claveau, Y.; Coll, L.; Dannoura, M.; Delagrange, S.; Domec, J.C.; Fatemi, F.; Feng, W.; Gargaglione, V.; Goto, Y.; Hagihara, A.; Hall, J.S.; Hamilton, S.; Harja, D.; Hiura, T.; Holdaway, R.; Hutley, L.B.; Ichie, T.; Jokela, E.J.; Kantola, A.; Kelly, J.W.G.; Kenzo, T.; King, D.; Kloeppel, B.D.; Kohyama, T.; Komiyama, A.; Laclau, J.P.; Lusk, C.H.; Maguire, D.A.; Le Maire, G.; Mäkelä, A.; Markesteijn, L.; Marshall, J.; McCulloh, K.; Miyata, I.; Mokany, K.; Mori, S.; Myster, R.W.; Nagano, M.; Naidu, S.L.; Nouvellon, Y.; O'Grady, A.P.; O'Hara, K.L.; Ohtsuka, T.; Osada, N.; Osunkoya, O.O.; Peri, P.L.; Petritan, A.M.; Poorter, L.; Portsmuth, A.; Potvin, C.; Ransijn, J.; Reid, D.; Ribeiro, S.C.; Roberts, S.D.; Rodríguez, R.; Acosta, A.S.; Santa-Regina, I.; Sasa, K.; Selaya, N.G.; Sillett, S.C.; Sterck, F.; Takagi, K.; Tange, T.; Tanouchi, H.; Tissue, D.; Umehara, T.; Utsugi, H.; Vadeboncoeur, M.A.; Valladares, F.; Vanninen, P.; Wang, J.R.; Wenk, E.; Williams, R.; De Aquino Ximenes, F.; Yamaba, A.; Yamada, T.; Yamakura, T.; Yanai, R.D.; York, R.A. url  doi
openurl 
  Title BAAD: a Biomass And Allometry Database for woody plants Type Journal Article
  Year 2015 Publication Ecology Abbreviated Journal (down) Ecology  
  Volume 96 Issue 5 Pages 1445  
  Keywords Allometric equations; Biomass allocation; Biomass partitioning; Global carbon cycle; Plant allometry; Plant traits  
  Abstract Understanding how plants are constructed; i.e., how key size dimensions and the amount of mass invested in different tissues varies among individuals; is essential for modeling plant growth, estimating carbon stocks, and mapping energy fluxes in the terrestrial biosphere. Allocation patterns can differ through ontogeny, but also among coexisting species and among species adapted to different environments. While a variety of models dealing with biomass allocation exist, we lack a synthetic understanding of the underlying processes. This is partly due to the lack of suitable data sets for validating and parameterizing models. To that end, we present the Biomass and allometry database (BAAD) for woody plants. The BAAD contains 259 634 measurements collected in 176 different studies, from 21 084 individuals across 678 species. Most of these data come from existing publications. However, raw data were rarely made public at time of publication. Thus the BAAD contains individual level data from different studies, transformed into standard units and variable names. The transformations were achieved using a common workflow for all raw data files. Other features that distinguish the BAAD are: (i) measurements were for individual plants rather than stand averages; (ii) individuals spanning a range of sizes were measured; (iii) inclusion of plants from 0.01-100 m in height; and (iii) biomass was estimated directly, i.e., not indirectly via allometric equations (except in very large trees where biomass was estimated from detailed subsampling). We included both wild and artificially grown plants. The data set contains the following size metrics: total leaf area; area of stem crosssection including sapwood, heartwood, and bark; height of plant and crown base, crown area, and surface area; and the dry mass of leaf, stem, branches, sapwood, heartwood, bark, coarse roots, and fine root tissues. We also report other properties of individuals (age, leaf size, leaf mass per area, wood density, nitrogen content of leaves and wood), as well as information about the growing environment (location, light, experimental treatment, vegetation type) where available. It is our hope that making these data available will improve our ability to understand plant growth, ecosystem dynamics, and carbon cycling in the world's vegetation.  
  Address Department of Disturbance Ecology, University of Bayreuth, Germany  
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  Notes Export Date: 1 September 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 686  
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Author Farjalla, V.F.; González, A.L.; Céréghino, R.; Dezerald, O.; Marino, N.A.C.; Piccoli, G.C.O.; Richardson, B.A.; Richardson, M.J.; Romero, G.Q.; Srivastava, D.S. doi  openurl
  Title Terrestrial support of aquatic food webs depends on light inputs: A geographically-replicated test using tank bromeliads Type Journal Article
  Year 2016 Publication Ecology Abbreviated Journal (down) Ecology  
  Volume 97 Issue 8 Pages 2147-2156  
  Keywords Allochthonous carbon; Allochthony; Aquatic food webs; Autochthonous carbon; Autochthony; Natural microcosms; Stable isotopic analysis; Tank bromeliads; Tropics  
  Abstract Food webs of freshwater ecosystems can be subsidized by allochthonous resources. However, it is still unknown which environmental factors regulate the relative consumption of allochthonous resources in relation to autochthonous resources. Here, we evaluated the importance of allochthonous resources (litterfall) for the aquatic food webs in Neotropical tank bromeliads, a naturally replicated aquatic microcosm. Aquatic invertebrates were sampled in more than 100 bromeliads within either open or shaded habitats and within five geographically distinct sites located in four different countries. Using stable isotope analyses, we determined that allochthonous sources comprised 74% (±17%) of the food resources of aquatic invertebrates. However, the allochthonous contribution to aquatic invertebrates strongly decreased from shaded to open habitats, as light incidence increased in the tanks. The density of detritus in the tanks had no impact on the importance of allochthonous sources to aquatic invertebrates. This overall pattern held for all invertebrates, irrespective of the taxonomic or functional group to which they belonged. We concluded that, over a broad geographic range, aquatic food webs of tank bromeliads are mostly allochthonous-based, but the relative importance of allochthonous subsidies decreases when light incidence favors autochthonous primary production. These results suggest that, for other freshwater systems, some of the between-study variation in the importance of allochthonous subsidies may similarly be driven by the relative availability of autochthonous resources. © 2016 by the Ecological Society of America.  
  Address Department of Animal Biology, Institute of Biology, University of Campinas (UNICAMP), PO Box 6109, Campinas-SP, Brazil  
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  Call Number EcoFoG @ webmaster @ Serial 687  
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Author Odonne, G.; van den Bel, M.; Burst, M.; Brunaux, O.; Bruno, M.; Dambrine, E.; Davy, D.; Desprez, M.; Engel, J.; Ferry, B.; Freycon, V.; Grenand, P.; Jérémie, S.; Mestre, M.; Molino, J.-F.; Petronelli, P.; Sabatier, D.; Hérault, B. url  doi
openurl 
  Title Long-term influence of early human occupations on current forests of the Guiana Shield Type Journal Article
  Year 2019 Publication Ecology Abbreviated Journal (down) Ecology  
  Volume 100 Issue 10 Pages e02806  
  Keywords Amazonian forest; archaeology; ethnobotany; Guiana Shield; historical ecology; pre-Columbian settlements; ring-ditched hills; alluvial plain; anthropogenic effect; archaeology; basal area; database; ethnobotany; forest ecosystem; historical ecology; occupation; paleoecology; species diversity; Amazonia; French Guiana; Guyana Shield; Annonaceae; Arecaceae; Burseraceae; Lauraceae; Lecythidaceae; Brazil; forest; French Guiana; human; occupation; tree; Brazil; Forests; French Guiana; Humans; Occupations; Trees  
  Abstract To decipher the long-term influences of pre-Columbian land occupations on contemporary forest structure, diversity, and functioning in Amazonia, most of the previous research focused on the alluvial plains of the major rivers of the Amazon basin. Terra firme, that is, nonflooded forests, particularly from the Guiana Shield, are yet to be explored. In this study, we aim to give new insights into the subtle traces of pre-Columbian influences on present-day forests given the archaeological context of terra firme forests of the Guiana Shield. Following archaeological prospects on 13 sites in French Guiana, we carried out forest inventories inside and outside archaeological sites and assessed the potential pre-Columbian use of the sampled tree species using an original ethnobotanical database of the Guiana Shield region. Aboveground biomass (320 and 380 T/ha, respectively), basal area (25–30 and 30–35 m2/ha, respectively), and tree density (550 and 700 stem/ha, respectively) were all significantly lower on anthropized plots (As) than on nonanthropized plots (NAs). Ancient human presence shaped the species composition of the sampled forests with Arecaceae, Burseraceae, and Lauraceae significantly more frequent in As and Annonaceae and Lecythidaceae more frequent in NAs. Although alpha diversity was not different between As and NAs, the presence of pre-Columbian sites enhances significantly the forest beta diversity at the landscape level. Finally, trees with edible fruits are positively associated with pre-Columbian sites, whereas trees used for construction or for their bark are negatively associated with pre-Columbian sites. Half a millennium after their abandonment, former occupied places from the inner Guiana Shield still bear noticeable differences with nonanthropized places. Considering the lack of data concerning archaeology of terra firme Amazonian forests, our results suggest that pre-Columbian influences on the structure (lower current biomass), diversity (higher beta diversity), and composition (linked to the past human tree uses) of current Amazonian forests might be more important than previously thought. © 2019 by the Ecological Society of America  
  Address Institut National Polytechnique Félix Houphouet-Boigny (INP-HB), Yamoussoukro, Ivory Coast, Cote d'Ivoire  
  Corporate Author Thesis  
  Publisher Ecological Society of America Place of Publication Editor  
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  ISSN 00129658 (Issn) ISBN Medium  
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  Call Number EcoFoG @ webmaster @ Serial 919  
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Author Srivastava, D.S.; Céréghino, R.; Trzcinski, M.K.; MacDonald, A.A.M.; Marino, N.A.C.; Mercado, D.A.; Leroy, C.; Corbara, B.; Romero, G.Q.; Farjalla, V.F.; Barberis, I.M.; Dézerald, O.; Hammill, E.; Atwood, T.B.; Piccoli, G.C.O.; Ospina-Bautista, F.; Carrias, J.-F.; Leal, J.S.; Montero, G.; Antiqueira, P.A.P.; Freire, R.; Realpe, E.; Amundrud, S.L.; de Omena, P.M.; Campos, A.B.A. doi  openurl
  Title Ecological response to altered rainfall differs across the Neotropics Type Journal Article
  Year 2020 Publication Ecology Abbreviated Journal (down) Ecology  
  Volume 101 Issue 4 Pages e02984  
  Keywords contingency; distributed experiment; freshwater; global change biology; macroinvertebrates; phytotelmata; precipitation; aquatic ecosystem; climate change; climate conditions; ecosystem response; extreme event; functional group; invertebrate; Neotropical Region; rainfall; species pool; Bacteria (microorganisms); Invertebrata; rain; animal; climate change; drought; ecosystem; invertebrate; Animals; Climate Change; Droughts; Ecosystem; Invertebrates; Rain  
  Abstract There is growing recognition that ecosystems may be more impacted by infrequent extreme climatic events than by changes in mean climatic conditions. This has led to calls for experiments that explore the sensitivity of ecosystems over broad ranges of climatic parameter space. However, because such response surface experiments have so far been limited in geographic and biological scope, it is not clear if differences between studies reflect geographic location or the ecosystem component considered. In this study, we manipulated rainfall entering tank bromeliads in seven sites across the Neotropics, and characterized the response of the aquatic ecosystem in terms of invertebrate functional composition, biological stocks (total invertebrate biomass, bacterial density) and ecosystem fluxes (decomposition, carbon, nitrogen). Of these response types, invertebrate functional composition was the most sensitive, even though, in some sites, the species pool had a high proportion of drought-tolerant families. Total invertebrate biomass was universally insensitive to rainfall change because of statistical averaging of divergent responses between functional groups. The response of invertebrate functional composition to rain differed between geographical locations because (1) the effect of rainfall on bromeliad hydrology differed between sites, and invertebrates directly experience hydrology not rainfall and (2) the taxonomic composition of some functional groups differed between sites, and families differed in their response to bromeliad hydrology. These findings suggest that it will be difficult to establish thresholds of “safe ecosystem functioning” when ecosystem components differ in their sensitivity to climatic variables, and such thresholds may not be broadly applicable over geographic space. In particular, ecological forecast horizons for climate change may be spatially restricted in systems where habitat properties mediate climatic impacts, and those, like the tropics, with high spatial turnover in species composition. © 2020 by the Ecological Society of America  
  Address Departamento de Ciencias Biológicas, Universidad de Caldas, Caldas, 170001, Colombia  
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  Publisher Ecological Society of America Place of Publication Editor  
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  ISSN 00129658 (Issn) ISBN Medium  
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  Call Number EcoFoG @ webmaster @ Serial 979  
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Author Talaga, S.; Delabie, J.H.C.; Dezerald, O.; Salas-Lopez, A.; Petitclerc, F.; Leroy, C.; Herault, B.; Céréghino, R.; Dejean, A. url  openurl
  Title A bromeliad species reveals invasive ant presence in urban areas of French Guiana Type Journal Article
  Year 2015 Publication Ecological Indicators Abbreviated Journal (down) Ecological Indicators  
  Volume 58 Issue Pages 1-7  
  Keywords Aechmea aquilega; Bioindicators; Non-specific ant-plant relationships; Surrogacy; Tank bromeliads; Urban ecology  
  Abstract Tank bromeliads, frequently associated with ants, are considered 'biodiversity amplifiers' for both aquatic and terrestrial organisms, and thus have a high ecological value. The focal species of this study, Aechmea aquilega, sheltered the colonies of 12 ant species in a Guianese rural habitat where Odontomachus haematodus, associated with 60% of these plants, was the most frequent. Unexpectedly, the ant species richness was higher in a compared urban habitat with 21 species, but two synanthropic and four invasive ants were noted among them. Consequently, we conducted baiting surveys (on the ground, on trees and on trees bearing A. aquilega) as well as complementary surveys using different sampling modes in urban areas to test if A. aquilega is a surrogate revealing the presence of certain invasive ants. During the baiting survey, we recorded four Neotropical and eight introduced invasive ants out of a total of 69 species. Of these 12 invasive species, five were noted by baiting A. aquilega (including two only noted in this way). A bootstrap simulation permitted us to conclude that A. aquilega significantly concentrates certain species of invasive ants. This was confirmed by complementary surveys, where we did not record further species. We conclude that baiting on trees bearing large epiphytes in human-modified, Neotropical areas is a relevant complement to the early detection of invasive ants. © 2015 Elsevier Ltd. All rights reserved.  
  Address CNRS Ecolab (UMR-CNRS 5245), 118 Route de Narbonne, Toulouse, France  
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  Notes Export Date: 23 June 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 607  
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Author Jona Lasinio, G.; Pollice, A.; Marcon, E.; Fano, E.A. doi  openurl
  Title Assessing the role of the spatial scale in the analysis of lagoon biodiversity. A case-study on the macrobenthic fauna of the Po River Delta Type Journal Article
  Year 2017 Publication Ecological Indicators Abbreviated Journal (down) Ecological Indicators  
  Volume 80 Issue Pages 303-315  
  Keywords Biodiversity partitioning; Lagoon biodiversity; Macrobenthic fauna; Mixed effects models; Tsallis entropy  
  Abstract The analysis of benthic assemblages is a valuable tool to describe the ecological status of transitional water ecosystems, but species are extremely sensitive and respond to both microhabitat and seasonal differences. The identification of changes in the composition of the macrobenthic community in specific microhabitats can then be used as an “early warning” for environmental changes which may affect the economic and ecological importance of lagoons, through their provision of Ecosystem Services. From a conservational point of view, the appropriate definition of the spatial aggregation level of microhabitats or local communities is of crucial importance. The main objective of this work is to assess the role of the spatial scale in the analysis of lagoon biodiversity. First, we analyze the variation in the sample coverage for alternative aggregations of the monitoring stations in three lagoons of the Po River Delta. Then, we analyze the variation of a class of entropy indices by mixed effects models, properly accounting for the fixed effects of biotic and abiotic factors and random effects ruled by nested sources of variability corresponding to alternative definitions of local communities. Finally, we address biodiversity partitioning by a generalized diversity measure, namely the Tsallis entropy, and for alternative definitions of the local communities. The main results obtained by the proposed statistical protocol are presented, discussed and framed in the ecological context. © 2017 Elsevier Ltd  
  Address Dipartimento di Scienze della Vita e Biotecnologie, Università degli Studi di Ferrara, Ferrara, Italy  
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  Notes Export Date: 12 June 2017 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 755  
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Author Picard, N.; Mortier, F.; Rossi, V.; Gourlet-Fleury, S. openurl 
  Title Clustering species using a model of population dynamics and aggregation theory Type Journal Article
  Year 2010 Publication Ecological Modelling Abbreviated Journal (down) Ecol. Model.  
  Volume 221 Issue 2 Pages 152-160  
  Keywords Aggregation theory; Species grouping; Species richness; Tropical rainforest; Usher model  
  Abstract The high species diversity of some ecosystems like tropical rainforests goes in pair with the scarcity of data for most species. This hinders the development of models that require enough data for fitting. The solution commonly adopted by modellers consists in grouping species to form more sizeable data sets. Classical methods for grouping species such as hierarchical cluster analysis do not take account of the variability of the species characteristics used for clustering. In this study a clustering method based on aggregation theory is presented. It takes account of the variability of species characteristics by searching for the grouping that minimizes the quadratic error (square bias plus variance) of some model's prediction. This method allows one to check whether the gain in variance brought by data pooling compensate for the bias that it introduces. This method was applied to a data set on 94 tree species in a tropical rainforest in French Guiana, using a Usher matrix model to predict species dynamics. An optimal trade-off between bias and variance was found when grouping species. Grouping species appeared to decrease the quadratic error, except when the number of groups was very small. This clustering method yielded species groups similar to those of the hierarchical cluster analysis using Ward's method when variance was small, that is when the number of groups was small. (C) 2009 Elsevier B.V. All rights reserved.  
  Address [Picard, Nicolas; Mortier, Frederic; Rossi, Vivien; Gourlet-Fleury, Sylvie] CIRAD, F-34398 Montpellier 5, France, Email: nicolas.picard@cirad.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 0304-3800 ISBN Medium  
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  Notes ISI:000273628800004 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 85  
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Author Flores, O.; Rossi, V.; Mortier, F. openurl 
  Title Autocorrelation offsets zero-inflation in models of tropical saplings density Type Journal Article
  Year 2009 Publication Ecological Modelling Abbreviated Journal (down) Ecol. Model.  
  Volume 220 Issue 15 Pages 1797-1809  
  Keywords Hierarchical Bayesian Modelling; Conditional Auto-Regressive model; Variable selection; Zero-Inflated Poisson; Posterior predictive; Paracou; French Guiana  
  Abstract Modelling the local density of tropical saplings can provide insights into the ecological processes that drive species regeneration and thereby help predict population recovery after disturbance. Yet, few studies have addressed the challenging issues in autocorrelation and zero-inflation of local density. This paper presents Hierarchical Bayesian Modelling (HBM) of sapling density that includes these two features. Special attention is devoted to variable selection, model estimation and comparison. We developed a Zero-Inflated Poisson (ZIP) model with a latent correlated spatial structure and compared it with non-spatial ZIP and Poisson models that were either autocorrelated (Spatial Generalized Linear Mixed, SGLM) or not (generalized linear models, GLM). In our spatial models, local density autocorrelation was modeled by a Conditional Auto-Regressive (CAR) process. 13 explicative variables described ecological conditions with respect to topography, disturbance, stand structure and intraspecific processes. Models were applied to six tropical tree species with differing biological attributes: Oxandra asbeckii, Eperua falcata, Eperua grandiflora, Dicorynia guianensis, Qualea rosea, and Tachigali melinonii. We built species-specific models using a simple method of variable selection based on a latent binary indicator. Our spatial models showed a close correlation between observed and estimated densities with site spatial structure being correctly reproduced. By contrast, the non-spatial models showed poor fits. Variable selection highlighted species-specific requirements and susceptibility to local conditions. Model comparison overall showed that the SGLM was the most accurate explanatory and predictive model. Surprisingly, zero-inflated models performed less well. Although the SZIP model was relevant with respect to data distribution, and more flexible with respect to response curves, its model complexity caused marked variability in parameter estimates. In the SUM, the spatial process alone accounted for zero-inflation in the data. A refinement of the hypotheses employed at the process level could compensate for distribution flaws at the data level. This study emphasized the importance of the HBM framework in improving the modelling of density-environment relationships. (C) 2008 Elsevier B.V. All rights reserved.  
  Address [Flores, O.] CNRS, Ctr Ecol Fonct & Evolut, UMR 5175, F-34293 Montpellier 5, France, Email: olivierflores@free.fr  
  Corporate Author Thesis  
  Publisher ELSEVIER SCIENCE BV Place of Publication Editor  
  Language Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0304-3800 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000267585400007 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 201  
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Author Phillips, P.D.; Thompson, I.S.; Silva, J.N.M.; van Gardingen, P.R.; Degen, B. openurl 
  Title Scaling up models of tree competition for tropical forest population genetics simulation Type Journal Article
  Year 2004 Publication Ecological Modelling Abbreviated Journal (down) Ecol. Model.  
  Volume 180 Issue 2-3 Pages 419-434  
  Keywords tropical rain; forest; population genetics; model SYMFOR; eco-gene; scaling up; competition  
  Abstract Understanding the effects of logging activity on genetic diversity is an important aspect of establishing the sustainability of selective logging management operations in tropical forests. Genetic variation is affected by selective logging directly, through the removal of and damage to trees within the population, and indirectly, through a change in the forest structure and environment in which the remaining population lives. Eco-Gene is a population genetics model applied to tropical forests over a scale of hundreds of hectares. SYMFOR is a modelling framework for individual-based spatially explicit ecological and management models applied to tropical forests over a scale of 0.25 4 ha. We have linked the models to enable simulations using processes involved in both models. To overcome problems of scale, the spatially explicit competition index calculated in SYMFOR simulations has been modelled such that it can be applied at scales representing much larger areas for which the data are not available, as required by Eco-Gene. The competition index is modelled as a distribution on a grid-square basis, and implemented in the linked Eco-Gene/SYMFOR system. Each tree within a grid-square is given a “relative competition” within the distribution, biased according to species. A competition index value is obtained for the tree by transforming the grid-square distribution to be relevant to the size of the tree, and extracting a value according to the tree's relative competition within the distribution. The distribution and each tree's relative competition within it change according to the effects of growth, mortality and logging activity. The model was calibrated using data from the Tapajos region of the Eastern Amazon forest. This paper describes the model, its calibration and validation and the implications of scaling up from an explicit representation to a modelled quantity. (C) 2004 Elsevier B.V. All rights reserved.  
  Address Embrapa Amazonia Oriental, BR-66095100 Belem, Para, Brazil, Email: paul.phillips@envams.co.uk  
  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 0304-3800 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000224635700012 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 234  
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