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Ploton, P.; Barbier, N.; Couteron, P.; Antin, C.M.; Ayyappan, N.; Balachandran, N.; Barathan, N.; Bastin, J.-F.; Chuyong, G.; Dauby, G.; Droissart, V.; Gastellu-Etchegorry, J.-P.; Kamdem, N.G.; Kenfack, D.; Libalah, M.; Mofack, G., II; Momo, S.T.; Pargal, S.; Petronelli, P.; Proisy, C.; Réjou-Méchain, M.; Sonké, B.; Texier, N.; Thomas, D.; Verley, P.; Zebaze Dongmo, D.; Berger, U.; Pélissier, R. | ||||
| Title | Toward a general tropical forest biomass prediction model from very high resolution optical satellite images | Type | Journal Article | ||
| Year | 2017 | Publication | Remote Sensing of Environment | Abbreviated Journal | |
| Volume | 200 | Issue | Pages | 140-153 | |
| Keywords | Canopy structure; Forest carbon; Fourier transform; Lacunarity; Passive optical imagery; Redd; Texture; Tropical forests | ||||
| Abstract | Very high spatial resolution (VHSR) optical satellite imagery has shown good potential to provide non-saturating proxies of tropical forest aboveground biomass (AGB) from the analysis of canopy texture, for instance through the Fourier Transform Textural Ordination method. Empirical case studies however showed that the relationship between Fourier texture features and forest AGB varies across forest types and regions of the world, limiting model transferability. A better understanding of the biophysical mechanisms on which canopy texture – forest AGB relation relies is a prerequisite to move toward broad scale applications. Here we simulated VHSR optical canopy scenes in identical sun-sensor geometry for 279 1-ha tropical forest inventory plots distributed across the tropics. Our aim was to assess the respective merits and complementarity of two types of texture analysis techniques (i.e. Fourier and lacunarity) on a set of forests with contrasted structure and geographical origin, and develop a general texture-based approach for tropical forest AGB mapping. Across forests, Fourier texture captured a gradient of stands mean crown size reflecting well the progressive changes in stand structure throughout forest aggradation phase (e.g. Pearson's r = − 0.42 with basal area) while lacunarity texture captured a gradient of canopy openness (, i.e. Pearson's r = − 0.57 with stand gap fraction). Both types of texture indices were highly complementary for predicting forest AGB at the global level (so-called FL-model). The residual error of the FL-model was structured across sites and could be partially captured with a bioclimatic proxy, further improving the performance of the global model (so-called FLE-model) and reducing site-level biases. The FLE model was tested on a set of real Pleiades images covering a mosaic of high-biomass forests in the Congo basin (mean AGB over 49 field plots: 359 ± 98 Mg ha− 1), leading to a significant relationship (R2 = 0.47 on validation data) with reasonable error levels (< 25% rRMSE). The increasing availability of VHSR optical sensors (such as from constellations of small satellite platforms) raises the possibility of routine repeated imaging of the world's tropical forests and suggests that texture-based analyses could become an essential tool in international efforts to monitor carbon emissions from deforestation and forest degradations (REDD +). © 2017 Elsevier Inc. | ||||
| Address | Technische Universität Dresden, Faculty of Environmental Sciences, Institute of Forest Growth and Forest Computer Sciences, Tharandt, Germany | ||||
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| Notes | Export Date: 25 September 2017 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 766 | ||
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Piponiot, C.; Sist, P.; Mazzei, L.; Peña-Claros, M.; Putz, F.E.; Rutishauser, E.; Shenkin, A.; Ascarrunz, N.; de Azevedo, C.P.; Baraloto, C.; França, M.; Guedes, M.; Honorio Coronado, E.N.; d'Oliveira, M.V.N.; Ruschel, A.R.; da Silva, K.E.; Doff Sotta, E.; de Souza, C.R.; Vidal, E.; West, T.A.P.; Herault, B. | ||||
| Title | Carbon recovery dynamics following disturbance by selective logging in Amazonian forests | Type | Journal Article | ||
| Year | 2016 | Publication | eLife | Abbreviated Journal | |
| Volume | 5 | Issue | Pages | e21394 | |
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| Abstract | When 2 Mha of Amazonian forests are disturbed by selective logging each year, more than 90 Tg of carbon (C) is emitted to the atmosphere. Emissions are then counterbalanced by forest regrowth. With an original modelling approach, calibrated on a network of 133 permanent forest plots (175 ha total) across Amazonia, we link regional differences in climate, soil and initial biomass with survivors' and recruits' C fluxes to provide Amazon-wide predictions of post-logging C recovery. We show that net aboveground C recovery over 10 years is higher in the Guiana Shield and in the west (21{plus minus}3 MgC ha-1) than in the south (12{plus minus}3 MgC ha-1) where environmental stress is high (low rainfall, high seasonality). We highlight the key role of survivors in the forest regrowth and elaborate a comprehensive map of post-disturbance C recovery potential in Amazonia. | ||||
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| Publisher | eLife Sciences Publications, Ltd | Place of Publication | Editor | Trumbore, S. | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2050-084x | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 702 | ||
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| Author |
Piponiot, C.; Rutishauser, E.; Derroire, G.; Putz, F.E.; Sist, P.; West, T.A.P.; Descroix, L.; Guedes, M.C.; Coronado, E.N.H.; Kanashiro, M.; Mazzei, L.; d’Oliveira, M.V.N.; Peña-Claros, M.; Rodney, K.; Ruschel, A.R.; Souza, C.R. de; Vidal, E.; Wortel, V.; Hérault, B. | ||||
| Title | Optimal strategies for ecosystem services provision in Amazonian production forests | Type | Journal Article | ||
| Year | 2019 | Publication | Environmental Research Letters | Abbreviated Journal | |
| Volume | 14 | Issue | 12 | Pages | 124090 |
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| Abstract | Although tropical forests harbour most of the terrestrial carbon and biological diversity on Earth they continue to be deforested or degraded at high rates. In Amazonia, the largest tropical forest on Earth, a sixth of the remaining natural forests is formally dedicated to timber extraction through selective logging. Reconciling timber extraction with the provision of other ecosystem services (ES) remains a major challenge for forest managers and policy-makers. This study applies a spatial optimisation of logging in Amazonian production forests to analyse potential trade-offs between timber extraction and recovery, carbon storage, and biodiversity conservation. Current logging regulations with unique cutting cycles result in sub-optimal ES-use efficiency. Long-term timber provision would require the adoption of a land-sharing strategy that involves extensive low-intensity logging, although high transport and road-building costs might make this approach economically unattractive. By contrast, retention of carbon and biodiversity would be enhanced by a land-sparing strategy restricting high-intensive logging to designated areas such as the outer fringes of the region. Depending on management goals and societal demands, either choice will substantially influence the future of Amazonian forests. Overall, our results highlight the need for revaluation of current logging regulations and regional cooperation among Amazonian countries to enhance coherent and trans-boundary forest management. | ||||
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| Publisher | IOP Publishing | Place of Publication | Editor | ||
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| ISSN | 1748-9326 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 910 | ||
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| Author |
Piponiot, C.; Rödig, E.; Putz, F.E.; Rutishauser, E.; Sist, P.; Ascarrunz, N.; Blanc, L.; Derroire, G.; Descroix, L.; Guedes, M.C.; Coronado, E.H.; Huth, A.; Kanashiro, M.; Licona, J.C.; Mazzei, L.; d’Oliveira, M.V.N.; Peña-Claros, M.; Rodney, K.; Shenkin, A.; de Souza, C.R.; Vidal, E.; West, T.A.P.; Wortel, V.; Herault, B. | ||||
| Title | Can timber provision from Amazonian production forests be sustainable? | Type | Journal Article | ||
| Year | 2019 | Publication | Environmental Research Letters | Abbreviated Journal | Environmental Research Letters |
| Volume | 14 | Issue | 6 | Pages | 064014 |
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| Abstract | Around 30 Mm3 of sawlogs are extracted annually by selective logging of natural production forests in Amazonia, Earth’s most extensive tropical forest. Decisions concerning the management of these production forests will be of major importance for Amazonian forests’ fate. To date, no regional assessment of selective logging sustainability supports decision-making. Based on data from 3500 ha of forest inventory plots, our modelling results show that the average periodic harvests of 20 m3 ha−1 will not recover by the end of a standard 30 year cutting cycle. Timber recovery within a cutting cycle is enhanced by commercial acceptance of more species and with the adoption of longer cutting cycles and lower logging intensities. Recovery rates are faster in Western Amazonia than on the Guiana Shield. Our simulations suggest that regardless of cutting cycle duration and logging intensities, selectively logged forests are unlikely to meet timber demands over the long term as timber stocks are predicted to steadily decline. There is thus an urgent need to develop an integrated forest resource management policy that combines active management of production forests with the restoration of degraded and secondary forests for timber production. Without better management, reduced timber harvests and continued timber production declines are unavoidable. | ||||
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| Publisher | IOP Publishing | Place of Publication | Editor | ||
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| ISSN | 1748-9326 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 875 | ||
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| Author |
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 | ||||
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| Notes | Export Date: 1 September 2018 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 813 | ||
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| Author |
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 | ||||
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| Notes | Export Date: 1 September 2016 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 688 | ||
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| Author |
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. |
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 753 | ||
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| Author |
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 | ||||
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| Publisher | PUBLICATIONS SCIENTIFIQUES DU MUSEUM, PARIS | Place of Publication | Editor | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1280-9551 | ISBN | Medium | ||
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| Notes | ISI:000273733000008 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 188 | ||
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| Author |
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 | |
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| 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 | ||||
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| Publisher | Frontiers Media | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1029 | ||
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| Author |
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 | ||||
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| Publisher | ELSEVIER SCIENCE BV | Place of Publication | Editor | ||
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| 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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