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5 results on '"Moses Libalah"'

1. Additive influences of soil and climate gradients drive tree community composition of Central African rain forests

Author

Nicolas Texier, Raphaël Pélissier, Donatien Zebaze, Moses Libalah, Stéphane Takoudjou Momo, Bonaventure Sonké, Narcisse Guy Kamdem, Nicolas Barbier, Gislain Ii Mofack, Claire Fortunel, Pierre Couteron, Simon L. Lewis, Gilles Dauby, Vincent Droissart, Pierre Ploton, Gyslene Kamdem, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud]), University of Yaoundé [Cameroun], Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire de Botanique et Ecologie, Université de Yaoundé I, Université libre de Bruxelles (ULB), Laboratoire de Botanique systématique et d'Ecologie [ENS Yaoudé], and Université de Yaoundé I-École normale supérieure [ENS] - Yaoundé 1

Subjects
0106 biological sciences, 010504 meteorology & atmospheric sciences, Soil gradient, Plant Science, Rainforest, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, 010603 evolutionary biology, 01 natural sciences, Climate gradient, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Cameroon, Relative species abundance, 0105 earth and related environmental sciences, 2. Zero hunger, Ecology, Species abundance, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, 15. Life on land, Tropical rain forest, Tree (data structure), Community composition, 13. Climate action, Species occurrence, Environmental science, Tropical rainforests, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience; Aim: Examining tree species-environment association can offer insight into the drivers of vegetation patterns and key information of practical relevance to forest management. Here, we aim to quantify the contribution of climate and soil gradients to variation in Central African tree species composition (abundance and occurrence). Location: Tropical rainforests of southern and eastern Cameroon. Methods: We established 82 1-ha permanent plots across seven localities and censused all trees ≥ 10 cm in diameter, representing a total of 37,733 trees and 455 species. In 60 of those plots, we measured ten soil variables describing texture and nutrients levels and extracted ten bioclimatic variables from global-gridded climate databases. We synthesized the main environmental gradients by conducting principal component analyses on climate and soil data respectively. We performed unconstrained and constrained non-symmetric correspondence analyses to account for the individual and joint contributions of climate and soil on species abundance and occurrence. Results: Climate and soil contributed similarly to variances of species abundance and occurrence (12–15 % variance for climate vs. 11–12 % variance for soil). Climate influence mostly concerns some abundant species, while some of the less abundant species were mainly driven by soil. Fractions of species variances accounted for by climate and soil show strong correlation when assessed from species occurrence and abundance data. Conclusion: Variation in occurrence and abundance of tropical forest trees can be partly shaped by both climate and soil gradients in Cameroon, which emphasizes the importance to jointly consider soil and climate in species distribution modeling. Less abundant species may express environmental influence differently than abundant species and convey complementary information about community assemblage. Though showing congruent patterns here, species abundance and occurrence reflect different interacting community processes and both should be examined to better understand vegetation patterns.

Published
2020
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2. A map of African humid tropical forest aboveground biomass derived from management inventories

Author

Ploton, Pierre, Mortier, Frédéric, Barbier, Nicolas, Cornu, Guillaume, Réjou-Méchain, Maxime, Rossi, Vivien, Alonso, Alfonso, Bastin, Jean-François, Bayol, Nicolas, Bénédet, Fabrice, Bissiengou, Pulchérie, Chuyong, Georges, Demarquez, Benoît, Doucet, Jean-Louis, Droissart, Vincent, Kamdem, Narcisse Guy, Kenfack, David, Memiaghe, Hervé, Moses, Libalah, Sonké, Bonaventure, Texier, Nicolas, Thomas, Duncan, Zebaze, Donatien, Pélissier, Raphaël, Gourlet-Fleury, Sylvie, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Forêts et Sociétés (UPR Forêts et Sociétés), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Département Environnements et Sociétés (Cirad-ES), Smithsonian Conservation Biology Institute, Research Unit of Landscape Ecology and Plant Production Systems, Université libre de Bruxelles (ULB), Centre national de la recherche scientifique et technologique (CENAREST), University of Buea, TERRA, Gembloux Agro-Bio Tech, Université de Yaoundé I, Smithsonian Conservation Biology Institute, Center for Conservation Education and Sustainability, MRC 705, Box 37012, Washington, DC, VA 20013-7012, USA, University of Yaoundé [Cameroun], Laboratoire de Botanique et Ecologie, Department of Preventive Medicine, University of Southern California (USC), Laboratoire de Botanique systématique et d'Ecologie [ENS Yaoudé], Université de Yaoundé I-École normale supérieure [ENS] - Yaoundé 1, and Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud])

Subjects
Statistics and Probability, Conservation of Natural Resources, Data Descriptor, Measurement(s) organic material, Climate Change, Digital curation, Library and Information Sciences, Forests, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, Technology Type, Education, Trees, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, biomasse aérienne des arbres, K01 - Foresterie - Considérations générales, Biomasse, Africa, Central, Biomass, Forêt tropicale humide, lcsh:Science, Sample Characteristic - Location, Sample Characteristic - Environment, Tropical Climate, Central Africa, Cartographie, Ecology, Inventaire forestier, Forestry, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, Computer Science Applications, Environmental sciences, Forested area, lcsh:Q, Statistics, Probability and Uncertainty, U30 - Méthodes de recherche, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, aboveground biomass, Climate sciences, Information Systems, Environmental Monitoring
Abstract

Forest biomass is key in Earth carbon cycle and climate system, and thus under intense scrutiny in the context of international climate change mitigation initiatives (e.g. REDD+). In tropical forests, the spatial distribution of aboveground biomass (AGB) remains, however, highly uncertain. There is increasing recognition that progress is strongly limited by the lack of field observations over large and remote areas. Here, we introduce the Congo basin Forests AGB (CoFor-AGB) dataset that contains AGB estimations and associated uncertainty for 59,857 1-km pixels aggregated from nearly 100,000 ha of in situ forest management inventories for the 2000 – early 2010s period in five central African countries. A comprehensive error propagation scheme suggests that the uncertainty on AGB estimations derived from c. 0.5-ha inventory plots (8.6–15.0%) is only moderately higher than the error obtained from scientific sampling plots (8.3%). CoFor-AGB provides the first large scale view of forest AGB spatial variation from field data in central Africa, the second largest continuous tropical forest domain of the world., Measurement(s) organic material • aboveground biomass Technology Type(s) digital curation Sample Characteristic - Environment forested area Sample Characteristic - Location Central Africa Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12504911

Published
2020
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3. Allometric Models to Estimate Leaf Area for Tropical African Broadleaved Forests

Author

Vincent Medjibe, Moses Libalah, Bonaventure Sonké, Nicolas Barbier, N. F. Sirri, Pierre Ploton, S. Momo Takoudjou, Gislain Ii Mofack, Narcisse Guy Kamdem, Higher Teachers' Training College, University of Yaoundé [Cameroun], Laboratoire de Botanique systématique et d'Ecologie [ENS Yaoudé], Université de Yaoundé I-École normale supérieure [ENS] - Yaoundé 1, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud]), University of Yaounde I, Université de Yaoundé I [Yaoundé]-École normale supérieure [ENS] - Yaoundé 1, and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])

Subjects
0106 biological sciences, Allometric models, Ecology, Allometric model, 04 agricultural and veterinary sciences, 15. Life on land, Tropical African broadleaved forests, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, 010603 evolutionary biology, 01 natural sciences, Leaf area, Geophysics, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, General Earth and Planetary Sciences, Environmental science, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, ComputingMilieux_MISCELLANEOUS
Abstract

Direct and semidirect estimations of leaf area (LA) and leaf area index (LAI) are scarce in dense tropical forests despite their importance in calibrating remote sensing products, forest dynamics, and biogeochemical models. We destructively sampled 61 trees belonging to 13 most abundant species in a semideciduous forest in southeastern Cameroon. For each tree, all leaves were weighed, and for a subsample of branches, leaves were counted and the LA measured. Allometric models were calibrated to allow semidirect estimation of LAI at tree and stand levels based on forest inventory data (R-2 = 0.7, bias = 21.2%, error = 39.5%) and on predictors that could be extracted from very high resolution remote sensing data (R-2 = 0.63, bias = 35.1%, error = 58.73). Using twenty-one 1-ha forest plots, stand level estimations of LAI ranged from 4.42-13.99. These values are higher than previous estimates generally obtained using indirect methods. These results may have important consequences on ecosystem exchanges and the role of tropical forest in global cycles. Plain Language Summary Leaf area (LA) and leaf area index (LAI) are useful parameters characterizing the plant-atmosphere interface where matter and energy are exchanged. However, direct or semidirect estimations are not common in dense tropical forests. In this study, we used a destructive data set of trees of varied species and sizes from the semideciduous forest of southeastern Cameroon to predict total tree LA. Based on this data, we developed operational allometric models to allow for semidirect estimation of LA and LAI at tree and stand levels. These models would be of considerable use for climate-vegetation modeling and remote sensing communities.

Published
2019
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4. Contrasted allometries between stem diameter, crown area, and tree height in five tropical biogeographic areas

Author

Vincent Droissart, Vanessa Hequet, Nicolas Texier, Philippe Birnbaum, Hervé Vandrot, Narcisse Guy Kamdem, Donatien Zebaze, Robin Pouteau, Pierre Couteron, Pierre Ploton, Thomas Boutreux, Moses Libalah, Elodie Blanchard, Thomas Ibanez, Cécile Antin, Nicolas Barbier, Grégoire Vincent, Bonaventure Sonké, Institut Agronomique Néo-Calédonien (IAC), Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud]), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Laboratoire de Botanique et Ecologie, Université de Yaoundé I, Laboratoire de Botanique systématique et d'Ecologie [ENS Yaoudé], Université de Yaoundé I-École normale supérieure [ENS] - Yaoundé 1, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Université de Yaoundé I [Yaoundé], Université de Yaoundé I [Yaoundé]-École normale supérieure [ENS] - Yaoundé 1, and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Lumière du jour, 0106 biological sciences, Canopy, 010504 meteorology & atmospheric sciences, Physiology, F62 - Physiologie végétale - Croissance et développement, forêt tropicale, Plant Science, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, F50 - Anatomie et morphologie des plantes, 01 natural sciences, Allométrie, Tree architecture, K01 - Foresterie - Considérations générales, Tronc, Crown light exposure, Ecology, Forestry, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, Houppier, Anatomie végétale, Forêt, Ontogeny, Écosystème forestier, Tree species, Rainforest, F40 - Écologie végétale, Biogéographie, Biology, 010603 evolutionary biology, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Stem size, Croissance, Power function, Scaling, 0105 earth and related environmental sciences, Allometry, Morphologie végétale, Ecologie, Niche differentiation, 15. Life on land, Tropical forest, Physical geography, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

Across five biogeographic areas, DBH-CA allometry was characterized by inter-site homogeneity and intra-site heterogeneity, whereas the reverse was observed for DBH-H allometry. Tree crowns play a central role in stand dynamics. Remotely sensed canopy images have been shown to allow inferring stand structure and biomass which suggests that allometric scaling between stems and crowns may be tight, although insufficiently investigated to date. Here, we report the first broad-scale assessment of stem vs. crown scaling exponents using measurements of bole diameter (DBH), total height (H), and crown area (CA) made on 4148 trees belonging to 538 species in five biogeographic areas across the wet tropics. Allometries were fitted with power functions using ordinary least-squares regressions on log-transformed data. The inter-site variability and intra-site (sub-canopy vs. canopy trees) variability of the allometries were evaluated by comparing the scaling exponents. Our results indicated that, in contrast to both DBH-H and H-CA allometries, DBH-CA allometry shows no significant inter-site variation. This fairly invariant scaling calls for increased effort in documenting crown sizes as part of tree morphology. Stability in DBH-CA allometry, indeed, suggests that some universal constraints are sufficiently pervasive to restrict the exponent variation to a narrow range. In addition, our results point to inverse changes in the scaling exponent of the DBH-CA vs. DBH-H allometries when shifting from sub-canopy to canopy trees, suggesting a change in carbon allocation when a tree reaches direct light. These results pave the way for further advances in our understanding of niche partitioning in tree species, tropical forest dynamics, and to estimate AGB in tropical forests from remotely sensed images.

Published
2016
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5. Seeing Central African forests through their largest trees

Author

Marc Dufrêne, Terese B. Hart, Corneille E. N. Ewango, Pierre Ploton, T. de Haulleville, Fidèle Baya, Jean-François Gillet, Sylvie Gourlet-Fleury, C De Cannière, Jean-Louis Doucet, Vincent Droissart, Gilles Dauby, Yadvinder Malhi, Duncan W. Thomas, Georges Chuyong, Jean-François Bastin, Adeline Serckx, Tariq Stévart, T. Kavali, David Kenfack, Hans Beeckman, Bonaventure Sonké, Jan Bogaert, Moses Libalah, D. Beina, C. H. Gonmadje, Pierre Couteron, Maxime Réjou-Méchain, Adeline Fayolle, Jean-Remy Makana, Danae Maniatis, Nicolas Barbier, Raphaël Pélissier, Research Unit of Landscape Ecology and Plant Production Systems, Université Libre de Bruxelles [Bruxelles] (ULB)-Université de Liège, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Université de Liège - Gembloux, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Oxford University Centre for the Environment (OUCE), University of Oxford [Oxford], Ministère des Eaux, Forêts, Chasse et Pêche, Royal Museum for Central Africa [Tervuren] (RMCA), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), University of Buéa, Diversité, adaptation, développement des plantes (UMR DIADE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Laboratoire de Physique des Solides (LPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Entomologie fonctionnelle et évolutive - Université de Liège, Wildlife Conservation Society, Smithsonian Tropical Research Institute, Laboratoire de Botanique systématique et d'Ecologie [ENS Yaoudé], Université de Yaoundé I [Yaoundé]-École normale supérieure [ENS] - Yaoundé 1, Institut de Mécanique des Fluides de Marseille, Herbarieum et Bibliothèque de Botanique africaine, Université Libre de Bruxelles [Bruxelles] (ULB), Sud Expert Plantes, ANR-12-EBID-0002,CoForTips,Forêts du Bassin du Congo: Biodiversité, Points de Basculement et Résilience des Systèmes Écologiques et Sociaux Forestiers.(2012), Université de Liège-Université libre de Bruxelles (ULB), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD [France-Sud]), Biens et services des écosystèmes forestiers tropicaux : l'enjeu du changement global (UPR BSEF), Ministère des Eaux, Forêts, Chasse et Pêche [République Centrafricaine], Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Université de Yaoundé I-École normale supérieure [ENS] - Yaoundé 1, Université libre de Bruxelles (ULB), and University of Oxford

Subjects
tropical forest, Tropical and subtropical dry broadleaf forests, F40 - Écologie végétale, distributions, Tropical trees, Biodiversity, Climate change, Forests, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, Models, Biological, size, Article, diversity, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Phénomènes atmosphériques, Forest ecology, K01 - Foresterie - Considérations générales, Bosecologie en Bosbeheer, Stock (geology), Forest floor, Multidisciplinary, biomass, Ecology, Agroforestry, Forestry, dynamics, 15. Life on land, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, PE&RC, Forest Ecology and Forest Management, Climatic change, Geography, Africa, Secondary forest, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, U30 - Méthodes de recherche
Abstract

Large tropical trees and a few dominant species were recently identified as the main structuring elements of tropical forests. However, such result did not translate yet into quantitative approaches which are essential to understand, predict and monitor forest functions and composition over large, often poorly accessible territories. Here we show that the above-ground biomass (AGB) of the whole forest can be predicted from a few large trees and that the relationship is proved strikingly stable in 175 1-ha plots investigated across 8 sites spanning Central Africa. We designed a generic model predicting AGB with an error of 14% when based on only 5% of the stems, which points to universality in forest structural properties. For the first time in Africa, we identified some dominant species that disproportionally contribute to forest AGB with 1.5% of recorded species accounting for over 50% of the stock of AGB. Consequently, focusing on large trees and dominant species provides precise information on the whole forest stand. This offers new perspectives for understanding the functioning of tropical forests and opens new doors for the development of innovative monitoring strategies., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2015
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