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Author (up) Phillips, O.L.; van der Heijden, G.; Lewis, S.L.; Lopez-Gonzalez, G.; Aragao, L.E.O.C.; Lloyd, J.; Malhi, Y.; Monteagudo, A.; Almeida, S.; Davila, E.A.; Amaral, I.; Andelman, S.; Andrade, A.; Arroyo, L.; Aymard, G.; Baker, T.R.; Blanc, L.; Bonal, D.; de Oliveira, A.C.A.; Chao, K.J.; Cardozo, N.D.; da Costa, L.; Feldpausch, T.R.; Fisher, J.B.; Fyllas, N.M.; Freitas, M.A.; Galbraith, D.; Gloor, E.; Higuchi, N.; Honorio, E.; Jimenez, E.; Keeling, H.; Killeen, T.J.; Lovett, J.C.; Meir, P.; Mendoza, C.; Morel, A.; Vargas, P.N.; Patino, S.; Peh, K.S.H.; Cruz, A.P.; Prieto, A.; Quesada, C.A.; Ramirez, F.; Ramirez, H.; Rudas, A.; Salamao, R.; Schwarz, M.; Silva, J.; Silveira, M.; Slik, J.W.F.; Sonke, B.; Thomas, A.S.; Stropp, J.; Taplin, J.R.D.; Vasquez, R.; Vilanova, E.
Title Drought-mortality relationships for tropical forests Type Journal Article
Year 2010 Publication New Phytologist Abbreviated Journal New Phytol.
Volume 187 Issue 3 Pages 631-646
Keywords Amazon; Borneo; drought; lags mortality; RAINFOR; trees; tropics
Abstract The rich ecology of tropical forests is intimately tied to their moisture status. Multi-site syntheses can provide a macro-scale view of these linkages and their susceptibility to changing climates. Here, we report pan-tropical and regional-scale analyses of tree vulnerability to drought. We assembled available data on tropical forest tree stem mortality before, during, and after recent drought events, from 119 monitoring plots in 10 countries concentrated in Amazonia and Borneo. In most sites, larger trees are disproportionately at risk. At least within Amazonia, low wood density trees are also at greater risk of drought-associated mortality, independent of size. For comparable drought intensities, trees in Borneo are more vulnerable than trees in the Amazon. There is some evidence for lagged impacts of drought, with mortality rates remaining elevated 2 yr after the meteorological event is over. These findings indicate that repeated droughts would shift the functional composition of tropical forests toward smaller, denser-wooded trees. At very high drought intensities, the linear relationship between tree mortality and moisture stress apparently breaks down, suggesting the existence of moisture stress thresholds beyond which some tropical forests would suffer catastrophic tree mortality.
Address [Phillips, Oliver L.; van der Heijden, Geertje; Lewis, Simon L.; Lopez-Gonzalez, Gabriela; Lloyd, Jon; Baker, Tim R.; Chao, Kuo-Jung; Feldpausch, Ted R.; Fyllas, Nikolaos M.; Gloor, Emanuel; Honorio, Euridice; Keeling, Helen; Quesada, Carlos A.; Schwarz, Michael] Univ Leeds, Sch Geog, Leeds LS2 9JT, W Yorkshire, England, Email: o.phillips@leeds.ac.uk
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 0028-646X ISBN Medium
Area Expedition Conference
Notes ISI:000280122500028 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 50
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Author (up) Phillips, P.D.; de Azevedo, C.P.; Degen, B.; Thompson, I.S.; Silva, J.N.M.; van Gardingen, P.R.
Title An individual-based spatially explicit simulation model for strategic forest management planning in the eastern Amazon Type Journal Article
Year 2004 Publication Ecological Modelling Abbreviated Journal Ecol. Model.
Volume 173 Issue 4 Pages 335-354
Keywords model; individual; tropical forest; tree; spatial; Brazil; Amazon; competition; species grouping; management; certification; regulation
Abstract A model to simulate the ecological processes of tree growth, mortality and recruitment, and the processes of forest management, in the terra firme forests of the eastern Amazon is described. It is implemented within the SYMFOR (http://www.symfor.org) framework. It is based on measurements of all trees that have a diameter greater than 5 cm from experimental plots in the Jari Cellulose and Tapajos National Forest areas over a 16-year period. Ten species groups are used to describe the natural processes affecting tree behaviour. Growth rates are calculated for each species group using the tree diameter and a competition index. Mortality and recruitment are simulated as stochastic processes. Recruitment probability is based on the predicted growth rate of a hypothetical tree. Options exist to vary the human interaction with the forest reflecting forest management decisions, as for other SYMFOR models. Model evaluation compares the performance of the model with data describing forest recovery for 16 years following logging. The model was applied to simulate current forest management practice in the Brazilian Amazon, with 40 m(3) ha(-1) of timber extracted with a cutting cycle of 30 years. Results show that yields are sustained for three harvests following the first logging of primary forest, but that the composition of timber moves towards lightwooded species rather than hardwooded. The predicted size of extracted trees decreases and the number of trees extracted increases with successive harvests, leading to a prediction of increased costs and lower profits for the logging company despite constant yields. The standing volume of all trees just before harvest is reduced by 15% over 150 years, with pioneer species becoming increasingly prevalent in the stand. The model, in the SYMFOR framework, can be used to help understand the differences between alternative forest management strategies in the Brazilian Amazon. Such knowledge is required to improve forest management, regulation and certification, and help to conserve the worlds largest remaining tropical forest. (C) 2003 Elsevier B.V. All rights reserved.
Address EMBRAPA Amazonia Oriental, BR-69011970 Manaus, Amazonas, 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:000220392200002 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 238
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Author (up) Phillips, P.D.; Thompson, I.S.; Silva, J.N.M.; van Gardingen, P.R.; Degen, B.
Title Scaling up models of tree competition for tropical forest population genetics simulation Type Journal Article
Year 2004 Publication Ecological Modelling Abbreviated Journal 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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Author (up) Picard, N.; Gourlet-Fleury, S.; Sist, P.
Title Using process-dependent groups of species to model the dynamics of a tropical rainforest Type Journal Article
Year 2003 Publication Modelling Forest Systems Abbreviated Journal
Volume Issue Pages 237-248
Keywords
Abstract The high tree species diversity in tropical forests is difficult to take into account in models. The usual solution consists of defining groups of species and then adjusting a set of parameters for each group. In this study, we address this issue by allowing a species to move from one species group to another, depending on the biological process that is concerned. We developed this approach with a matrix model of forest dynamics, for a tropical rainforest in French Guiana, at Paracou, focusing on the methodological aspects. The forest dynamics is split into three components: recruitment, growth and mortality. We then built five recruitment groups, five growth groups and five mortality groups. One species is characterized by a combination of the three groups, thus yielding in total 5 X 5 X 5 = 125 possibilities, out of which 43 are actually observed. The resulting matrix model provides a better view of the floristic composition of the forest, and does not have more parameters than it would have with five global species groups. However, its predictions are no more precise than those of the matrix model based on five global groups.
Address Cirad Foret, Montpellier, France
Corporate Author Thesis
Publisher CABI PUBLISHING Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes ISI:000231866400021 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 249
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Author (up) Picard, N.; Mortier, F.; Rossi, V.; Gourlet-Fleury, S.
Title Clustering species using a model of population dynamics and aggregation theory Type Journal Article
Year 2010 Publication Ecological Modelling Abbreviated Journal 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
Area Expedition Conference
Notes ISI:000273628800004 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 85
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Author (up) Picard, Nicolas ; Mortier, Frédéric ; Ploton, Pierre ; Liang, Jingjing ; Derroire, Géraldine ; Bastin, Jean-François ; Ayyappan, Narayanan ; Bénédet, Fabrice ; Bosela, Faustin Boyemba ; Clark, Connie J. ; Crowther, Thomas W. ; Obiang, Nestor Laurier Engone ; Forni, Eric ; Harris, David ; Ngomanda, Alfred ; Poulsen, John R. ; Sonké, Bonaventure ; Couteron, Pierre ; Gourley-Fleury, Sylvie
Title Using Model Analysis to Unveil Hidden Patterns in Tropical Forest structures Type Journal Article
Year 2021 Publication Frontiers in Ecology and Evolution Abbreviated Journal
Volume 9 Issue Pages 599200
Keywords
Abstract When ordinating plots of tropical rain forests using stand-level structural attributes such as biomass, basal area and the number of trees in different size classes, two patterns often emerge: a gradient from poorly to highly stocked plots and high positive correlations between biomass, basal area and the number of large trees. These patterns are inherited from the demographics (growth, mortality and recruitment) and size allometry of trees and tend to obscure other patterns, such as site differences among plots, that would be more informative for inferring ecological processes. Using data from 133 rain forest plots at nine sites for which site differences are known, we aimed to filter out these patterns in forest structural attributes to unveil a hidden pattern. Using a null model framework, we generated the anticipated pattern inherited from individual allometric patterns. We then evaluated deviations between the data (observations) and predictions of the null model. Ordination of the deviations revealed site differences that were not evident in the ordination of observations. These sites differences could be related to different histories of large-scale forest disturbance. By filtering out patterns inherited from individuals, our model analysis provides more information on ecological processes
Address
Corporate Author Thesis
Publisher Frontiers Media Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 1029
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Author (up) Pickett, K.M.; Carpenter, J.M.; Dejean, A.
Title “Basal” but not primitive: the nest of Apoica arborea de Saussure, 1854 (Insecta, Hymenoptera, Vespidae, Polistinae) Type Journal Article
Year 2009 Publication Zoosystema Abbreviated Journal Zoosystema
Volume 31 Issue 4 Pages 945-948
Keywords Insecta; Hymenoptera; Vespidae; Polistinae; Apoica; social wasps; nest architecture; mosaic evolution
Abstract The first nest of Apoica arborea ever collected is reported. Characteristics of the unusual nest design are discussed relative to other members of the genus Apoica and other epiponine genera. The characteristics of its nest architecture are a mosaic of primitive and derived features for the Polistinae, and thus the nest design is not properly interpreted as the primitive condition from which other swarm-founding wasp nest designs are derived. The frequent conflation of “basal” and primitive is discussed.
Address [Pickett, Kurt M.] Univ Vermont, Dept Biol, Burlington, VT 05401 USA, Email: kurt.pickett@uvm.edu
Corporate Author Thesis
Publisher PUBLICATIONS SCIENTIFIQUES DU MUSEUM, PARIS Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1280-9551 ISBN Medium
Area Expedition Conference
Notes ISI:000273733000008 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 188
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Author (up) Pierrejean, I.; Mehinto, T.; Beauchene, J.
Title Comparative Analysis of Three Different Methods Used to Determine the Elastic Modulus for a Choice of Tropical Guianese Wood Species Type Journal Article
Year 2017 Publication Pro Ligno Abbreviated Journal
Volume 13 Issue 1 Pages 3-17
Keywords density; modulus of elasticity; static and dynamic tests; tropical woods
Abstract This study compares variability in the longitudinal Modulus of Elasticity (MOE) values, measured by three different methods, for eight tropical wood species covering a wide range of densities, a property that has been little described in the literature for some of the species studied. The modulus of elasticity in wood species is one of the main mechanical properties measured to characterize wood materials. However, this property is seldom described for the tropical wood species studied here, and the method used is often variable. The aim is to answer the following questions. In the methods used, what are the main variability factors which influence modulus measurement? Is the modulus different with regard to the solicitation direction (radial or tangential)? Which relationship exists between modulus and density for these species?
The samples were subjected to the four-point bending test, then to the free vibration test and to the forced-vibration test (which allows tests on small samples).The samples were subjected to stress in radial and tangential directions. The modulus values obtained by the different methods were well correlated for most of the species. The relationship between modulus and density was very good at inter-specific level because sampling covered a wide range of densities. But this relationship was not so good for each of the species sampled.
This kind of test was not appropriate for detecting differences in behavior between the two directions of solicitation for these species. The main features of the three methods were summarized, highlighting the advantages of each for the species studied.
Address
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 753
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Author (up) Piponiot, C.; Cabon, A.; Descroix, L.; Dourdain, A.; Mazzei, L.; Ouliac, B.; Rutishauser, E.; Sist, P.; Herault, B.
Title A methodological framework to assess the carbon balance of tropical managed forests Type Journal Article
Year 2016 Publication Carbon Balance and Management Abbreviated Journal Carbon Balance and Management
Volume 11 Issue 1 Pages
Keywords Amazonia; Carbon cycle; Error propagation; Production forests; Selective logging
Abstract Background: Managed forests are a major component of tropical landscapes. Production forests as designated by national forest services cover up to 400 million ha, i.e. half of the forested area in the humid tropics. Forest management thus plays a major role in the global carbon budget, but with a lack of unified method to estimate carbon fluxes from tropical managed forests. In this study we propose a new time- and spatially-explicit methodology to estimate the above-ground carbon budget of selective logging at regional scale. Results: The yearly balance of a logging unit, i.e. the elementary management unit of a forest estate, is modelled by aggregating three sub-models encompassing (i) emissions from extracted wood, (ii) emissions from logging damage and deforested areas and (iii) carbon storage from post-logging recovery. Models are parametrised and uncertainties are propagated through a MCMC algorithm. As a case study, we used 38 years of National Forest Inventories in French Guiana, northeastern Amazonia, to estimate the above-ground carbon balance (i.e. the net carbon exchange with the atmosphere) of selectively logged forests. Over this period, the net carbon balance of selective logging in the French Guianan Permanent Forest Estate is estimated to be comprised between 0.12 and 1.33 Tg C, with a median value of 0.64 Tg C. Uncertainties over the model could be diminished by improving the accuracy of both logging damage and large woody necromass decay submodels. Conclusions: We propose an innovating carbon accounting framework relying upon basic logging statistics. This flexible tool allows carbon budget of tropical managed forests to be estimated in a wide range of tropical regions. © 2016 The Author(s).
Address CNRS, UMR EcoFoG, AgroParisTech, Inra, Université de la Guyane, Université des Antilles, Cirad, Campus Agronomique, Kourou, French Guiana
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 ISBN Medium
Area Expedition Conference
Notes Export Date: 1 September 2016 Approved no
Call Number EcoFoG @ webmaster @ Serial 688
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Author (up) Piponiot, C.; Derroire, G.; Descroix, L.; Mazzei, L.; Rutishauser, E.; Sist, P.; Hérault, B.
Title Assessing timber volume recovery after disturbance in tropical forests – A new modelling framework Type Journal Article
Year 2018 Publication Ecological Modelling Abbreviated Journal
Volume 384 Issue Pages 353-369
Keywords Disturbance; Ecosystem modelling; Recovery; Sustainability; Tropical forest management
Abstract One third of contemporary tropical forests is designated by national forest services for timber production. Tropical forests are also increasingly affected by anthropogenic disturbances. However, there is still much uncertainty around the capacity of tropical forests to recover their timber volume after logging as well as other disturbances such as fires, large blow-downs and extreme droughts, and thus on the long-term sustainability of logging. We developed an original Bayesian hierarchical model of Volume Dynamics with Differential Equations (VDDE) to infer the dynamic of timber volumes as the result of two ecosystem processes: volume gains from tree growth and volume losses from tree mortality. Both processes are expressed as explicit functions of the forest maturity, i.e. the overall successional stage of the forest that primarily depends on the frequency and severity of the disturbances that the forest has undergone. As a case study, the VDDE model was calibrated with data from Paracou, a long-term disturbance experiment in a neotropical forest where over 56 ha of permanent forest plots were logged with different intensities and censused for 31 years. With this model, we could predict timber recovery at Paracou at the end of a cutting cycle depending on the logging intensity, the rotation cycle length, and the proportion of commercial volume. The VDDE modelling framework developed presents three main advantages: (i) it can be calibrated with large tree inventories which are widely available from national forest inventories or logging concession management plans and are easy to measure, both on the field and with remote sensing; (ii) it depends on only a few input parameters, which can be an advantage in tropical regions where data availability is scarce; (iii) the modelling framework is flexible enough to explicitly include the effect of other types of disturbances (both natural and anthropogenic: e.g. blow-downs, fires and climate change) on the forest maturity, and thus to predict future timber provision in the tropics in a context of global changes. © 2018 Elsevier B.V.
Address INPHB (Institut National Polytechnique Félix Houphouet Boigny), Yamoussoukro, Cote d'Ivoire
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 ISBN Medium
Area Expedition Conference
Notes Export Date: 1 September 2018 Approved no
Call Number EcoFoG @ webmaster @ Serial 813
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