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Camera traps (CTs) have been increasingly used for wildlife monitoring worldwide. In the tropics, most CT inventories target wildlife‐friendly sites, and CTs are commonly placed towards wildlife trails. However, it has been argued that this placement strategy potentially provides biased results in comparison to more systematic or randomized approaches. Here, we investigated the impact of CT placement on the remotely sensed mammal diversity in a tropical forest in Gabon by comparing pairs of systematically placed and wildlife‐trail‐oriented CTs. Our survey protocol consisted of 15–17 sampling points arranged on a 2 km2 grid and left for one month in the field. This protocol was replicated sequentially in four areas. Each sampling point comprised a CT pair: the ‘systematic CT’, installed at the theoretical point and systematically oriented towards the most uncluttered view; and the ‘trail CT’, placed within a 20‐m radius and facing a wildlife trail. For the vast majority of species, the detection probabilities were comparable between placements. Species average capture rates were slightly higher for trail‐based CTs, though this trend was not significant for any species. Therefore, the species richness and composition of the overall community, such as the spatial distribution patterns (from evenly spread to site‐restricted) of individual species, were similarly depicted by both placements. Opting for a systematic orientation ensures that pathways used preferentially by some species—and avoided by others—will be sampled proportionally to their density in the forest undergrowth. However, trail‐based placement is routinely used, already producing standardised data within large‐scale monitoring programmes. Here, both placements provided a comparable picture of the mammal community, though it might not be necessarily true in depauperate areas. Both types of CT data can nevertheless be combined in multi‐site analyses, since methods now allow accounting for differences in study design and detection bias in original CT data.

Adaptive evolution is a major driver of organism diversification, but the links between phenotypic traits and environmental niche remain little documented in tropical trees. Moreover, trait‐niche relationships are complex because a correlation between the traits and environmental niches displayed by a sample of species may result from (a) convergent evolution if different environmental conditions have selected different sets of traits, and/or (b) phylogenetic inertia if niche and morphological differences between species are simply function of their phylogenetic divergence, in which case the trait‐niche correlation does not imply any direct causal link. Here, we aim to assess the respective roles of phylogenetic inertia and convergent evolution in shaping the differences of botanical traits and environmental niches among congeneric African tree species that evolved in different biomes.This issue was addressed with the tree genus Guibourtia Benn. (Leguminosae and Detarioideae), which contains 13 African species occupying various forest habitat types, from rain forest to dry woodlands, with different climate and soil conditions. To this end, we combined morphological data with ecological niche modelling and used a highly resolved plastid phylogeny of the 13 African Guibourtia species.First, we demonstrated phylogenetic signals in both morphological traits (Mantel test between phylogenetic and morphological distances between species: r = .24, p = .031) and environmental niches (Mantel test between phylogenetic and niche distances between species: r = .23, p = .025). Second, we found a significant correlation between morphology and niche, at least between some of their respective dimensions (Mantel's r = .32, p = .013), even after accounting for phylogenetic inertia (Phylogenetic Independent Contrast: r = .69, p = .018). This correlation occurred between some leaflet and flower traits and solar radiation, relative humidity, precipitations, and temperature range.Our results demonstrate the convergent evolution of some morphological traits in response to climatic factors in congeneric tree species and highlight the action of selective forces, along with neutral ones, in shaping the divergence between congeneric tropical plants., Here, we aim to assess the respective roles of phylogenetic inertia and convergent evolution in shaping the differences of botanical traits and environmental niches among congeneric African tree species that evolved in different biomes. Our results demonstrate for the first time the convergent evolution of some morphological traits in response to climatic factors in congeneric tree species and highlight the action of selective forces, along with neutral ones, in shaping the divergence between congeneric tropical plants.

Made available in DSpace on 2021-06-25T11:16:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Agence Nationale Des Parcs Nationaux Centre for International Forestry Research Departamento Administrativo de Ciencia, Tecnología e Innovación (COLCIENCIAS) David and Lucile Packard Foundation European Space Agency Leverhulme Trust Gordon and Betty Moore Foundation Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundação de Amparo à Pesquisa do Estado de Goiás European Research Council Belgian Federal Science Policy Office Vlaamse Interuniversitaire Raad Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) National Science Foundation Natural Environment Research Council Royal Society National Geographic Society Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Tropical forests are the most diverse and productive ecosystems on Earth. While better understanding of these forests is critical for our collective future, until quite recently efforts to measure and monitor them have been largely disconnected. Networking is essential to discover the answers to questions that transcend borders and the horizons of funding agencies. Here we show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots. We review the major scientific discoveries of this work and show how this process is changing tropical forest science. Our core approach involves linking long-term grassroots initiatives with standardized protocols and data management to generate robust scaled-up results. By connecting tropical researchers and elevating their status, our Social Research Network model recognises the key role of the data originator in scientific discovery. Conceived in 1999 with RAINFOR (South America), our permanent plot networks have been adapted to Africa (AfriTRON) and Southeast Asia (T-FORCES) and widely emulated worldwide. Now these multiple initiatives are integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. Collectively these are transforming understanding of tropical forests and their biospheric role. Together we have discovered how, where and why forest carbon and biodiversity are responding to climate change, and how they feedback on it. This long-term pan-tropical collaboration has revealed a large long-term carbon sink and its trends, as well as making clear which drivers are most important, which forest processes are affected, where they are changing, what the lags are, and the likely future responses of tropical forests as the climate continues to change. By leveraging a remarkably old technology, plot networks are sparking a very modern revolution in tropical forest science. In the future, humanity can benefit greatly by nurturing the grassroots communities now collectively capable of generating unique, long-term understanding of Earth's most precious forests. Resumen: Los bosques tropicales son los ecosistemas más diversos y productivos del mundo y entender su funcionamiento es crítico para nuestro futuro colectivo. Sin embargo, hasta hace muy poco, los esfuerzos para medirlos y monitorearlos han estado muy desconectados. El trabajo en redes es esencial para descubrir las respuestas a preguntas que trascienden las fronteras y los plazos de las agencias de financiamiento. Aquí mostramos cómo una comunidad global está respondiendo a los desafíos de la investigación en ecosistemas tropicales a través de diversos equipos realizando mediciones árbol por árbol en miles de parcelas permanentes de largo plazo. Revisamos los descubrimientos más importantes de este trabajo y discutimos cómo este proceso está cambiando la ciencia relacionada a los bosques tropicales. El enfoque central de nuestro esfuerzo implica la conexión de iniciativas locales de largo plazo con protocolos estandarizados y manejo de datos para producir resultados que se puedan trasladar a múltiples escalas. Conectando investigadores tropicales, elevando su posición y estatus, nuestro modelo de Red Social de Investigación reconoce el rol fundamental que tienen, para el descubrimiento científico, quienes generan o producen los datos. Concebida en 1999 con RAINFOR (Suramérica), nuestras redes de parcelas permanentes han sido adaptadas en África (AfriTRON) y el sureste asiático (T-FORCES) y ampliamente replicadas en el mundo. Actualmente todas estas iniciativas están integradas a través de la ciber-infraestructura de ForestPlots.net, conectando colegas de 54 países en 24 redes diferentes de parcelas. Colectivamente, estas redes están transformando nuestro conocimiento sobre los bosques tropicales y el rol de éstos en la biósfera. Juntos hemos descubierto cómo, dónde y porqué el carbono y la biodiversidad de los bosques tropicales está respondiendo al cambio climático y cómo se retroalimentan. Esta colaboración pan-tropical de largo plazo ha expuesto un gran sumidero de carbono y sus tendencias, mostrando claramente cuáles son los factores más importantes, qué procesos se ven afectados, dónde ocurren los cambios, los tiempos de reacción y las probables respuestas futuras mientras el clima continúa cambiando. Apalancando lo que realmente es una tecnología antigua, las redes de parcelas están generando una verdadera y moderna revolución en la ciencia tropical. En el futuro, la humanidad puede beneficiarse enormemente si se nutren y cultivan comunidades de investigadores de base, actualmente con la capacidad de generar información única y de largo plazo para entender los que probablemente son los bosques más preciados de la tierra. Resumo: Florestas tropicais são os ecossistemas mais diversos e produtivos da Terra. Embora uma boa compreensão destas florestas seja crucial para o nosso futuro coletivo, até muito recentemente os esforços de medições e monitoramento foram amplamente desconexos. É essencial formarmos redes para obtermos respostas que transcendem fronteiras e horizontes de agências financiadoras. Neste estudo nós mostramos como uma comunidade global está respondendo aos desafios da pesquisa de ecossistemas tropicais, com equipes diversas medindo florestas, árvore por árvore, em milhares de parcelas monitoradas à longo prazo. Nós revisamos as maiores descobertas científicas deste trabalho, e mostramos também como este processo está mudando a ciência de florestas tropicais. Nossa abordagem principal envolve unir iniciativas de base a protocolos padronizados e gerenciamento de dados a fim de gerar resultados robustos em escalas ampliadas. Ao conectar pesquisadores tropicais e elevar seus status, nosso modelo de Rede de Pesquisa Social reconhece o papel-chave do produtor dos dados na descoberta científica. Concebida em 1999 com o RAINFOR (América do Sul), nossa rede de parcelas permanentes foi adaptada para África (AfriTRON) e Sudeste asiático (T-FORCES), e tem sido extensamente reproduzida em todo o mundo. Agora estas múltiplas iniciativas estão integradas através de uma infraestrutura cibernética do ForestPlots.net, conectando colegas de 54 países de 24 redes de parcelas. Estas iniciativas estão transformando coletivamente o entendimento das florestas tropicais e seus papéis na biosfera. Juntos nós descobrimos como, onde e por que o carbono e a biodiversidade da floresta estão respondendo às mudanças climáticas, e seus efeitos de retroalimentação. Esta duradoura colaboração pantropical revelou um grande sumidouro de carbono persistente e suas tendências, assim como tem evidenciado quais direcionadores são mais importantes, quais processos florestais são mais afetados, onde eles estão mudando, seus atrasos no tempo de resposta, e as prováveis respostas das florestas tropicais conforme o clima continua a mudar. Dessa forma, aproveitando uma notável tecnologia antiga, redes de parcelas acendem faíscas de uma moderna revolução na ciência das florestas tropicais. No futuro a humanidade pode se beneficiar incentivando estas comunidades basais que agora são coletivamente capazes de gerar conhecimentos únicos e duradouros sobre as florestas mais preciosas da Terra. Résume: Les forêts tropicales sont les écosystèmes les plus diversifiés et les plus productifs de la planète. Si une meilleure compréhension de ces forêts est essentielle pour notre avenir collectif, jusqu'à tout récemment, les efforts déployés pour les mesurer et les surveiller ont été largement déconnectés. La mise en réseau est essentielle pour découvrir les réponses à des questions qui dépassent les frontières et les horizons des organismes de financement. Nous montrons ici comment une communauté mondiale relève les défis de la recherche sur les écosystèmes tropicaux avec diverses équipes qui mesurent les forêts arbre après arbre dans de milliers de parcelles permanentes. Nous passons en revue les principales découvertes scientifiques de ces travaux et montrons comment ce processus modifie la science des forêts tropicales. Notre approche principale consiste à relier les initiatives de base à long terme à des protocoles standardisés et une gestion de données afin de générer des résultats solides à grande échelle. En reliant les chercheurs tropicaux et en élevant leur statut, notre modèle de réseau de recherche sociale reconnaît le rôle clé de l'auteur des données dans la découverte scientifique. Conçus en 1999 avec RAINFOR (Amérique du Sud), nos réseaux de parcelles permanentes ont été adaptés à l'Afrique (AfriTRON) et à l'Asie du Sud-Est (T-FORCES) et largement imités dans le monde entier. Ces multiples initiatives sont désormais intégrées via l'infrastructure ForestPlots.net, qui relie des collègues de 54 pays à travers 24 réseaux de parcelles. Ensemble, elles transforment la compréhension des forêts tropicales et de leur rôle biosphérique. Ensemble, nous avons découvert comment, où et pourquoi le carbone forestier et la biodiversité réagissent au changement climatique, et comment ils y réagissent. Cette collaboration pan-tropicale à long terme a révélé un important puits de carbone à long terme et ses tendances, tout en mettant en évidence les facteurs les plus importants, les processus forestiers qui sont affectés, les endroits où ils changent, les décalages et les réactions futures probables des forêts tropicales à mesure que le climat continue de changer. En tirant parti d'une technologie remarquablement ancienne, les réseaux de parcelles déclenchent une révolution très moderne dans la science des forêts tropicales. À l'avenir, l'humanité pourra grandement bénéficier du soutien des communautés de base qui sont maintenant collectivement capables de générer une compréhension unique et à long terme des forêts les plus précieuses de la Terre. Abstrak: Hutan tropika adalah di antara ekosistem yang paling produktif dan mempunyai kepelbagaian biodiversiti yang tinggi di seluruh dunia. Walaupun pemahaman mengenai hutan tropika amat penting untuk masa depan kita, usaha-usaha untuk mengkaji dan mengawas hutah-hutan tersebut baru sekarang menjadi lebih diperhubungkan. Perangkaian adalah sangat penting untuk mencari jawapan kepada soalan-soalan yang menjangkaui sempadan dan batasan agensi pendanaan. Di sini kami menunjukkan bagaimana sebuah komuniti global bertindak balas terhadap cabaran penyelidikan ekosistem tropika melalui penglibatan pelbagai kumpulan yang mengukur hutan secara pokok demi pokok dalam beribu-ribu plot jangka panjang. Kami meninjau semula penemuan saintifik utama daripada kerja ini dan menunjukkan bagaimana proses ini sedang mengubah bidang sains hutan tropika. Teras pendekatan kami memberi tumpuan terhadap penghubungan inisiatif akar umbi jangka panjang dengan protokol standar serta pengurusan data untuk mendapatkan hasil skala besar yang kukuh. Dengan menghubungkan penyelidik-penyelidik tropika dan meningkatkan status mereka, model Rangkaian Penyelidikan Sosial kami mengiktiraf kepentingan peranan pengasas data dalam penemuan saintifik. Bermula dengan pengasasan RAINFOR (Amerika Selatan) pada tahun 1999, rangkaian-rangkaian plot kekal kami kemudian disesuaikan untuk Afrika (AfriTRON) dan Asia Tenggara (T-FORCES) dan selanjutnya telah banyak dicontohi di seluruh dunia. Kini, inisiatif-inisiatif tersebut disepadukan melalui infrastruktur siber ForestPlots.net yang menghubungkan rakan sekerja dari 54 negara di 24 buah rangkaian plot. Secara kolektif, rangkaian ini sedang mengubah pemahaman tentang hutan tropika dan peranannya dalam biosfera. Kami telah bekerjasama untuk menemukan bagaimana, di mana dan mengapa karbon serta biodiversiti hutan bertindak balas terhadap perubahan iklim dan juga bagaimana mereka saling bermaklum balas. Kolaborasi pan-tropika jangka panjang ini telah mendedahkan sebuah sinki karbon jangka panjang serta arah alirannya dan juga menjelaskan pemandu-pemandu perubahan yang terpenting, di mana dan bagaimana proses hutan terjejas, masa susul yang ada dan kemungkinan tindakbalas hutan tropika pada perubahan iklim secara berterusan di masa depan. Dengan memanfaatkan pendekatan lama, rangkaian plot sedang menyalakan revolusi yang amat moden dalam sains hutan tropika. Pada masa akan datang, manusia sejagat akan banyak mendapat manfaat jika memupuk komuniti-komuniti akar umbi yang kini berkemampuan secara kolektif menghasilkan pemahaman unik dan jangka panjang mengenai hutan-hutan yang paling berharga di dunia. Instituto de Ecología Regional (IER) Universidad Nacional de Tucumán (UNT) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Facultad de Ciencias Agrarias Universidad Nacional de Jujuy James Cook University (JCU) CSIRO (Commonwealth Scientific and Industrial Research Organisation) School of Land & Food University of Tasmania CSIRO Tropical Forest Research Centre Independent Researcher Environmental Protection Agency (EPA) Centre for Tropical Environmental and Sustainability Science (TESS) College of Marine and Environmental Sciences James Cook University Centre for Tropical Environmental and Sustainability Science College of Science and Engineering James Cook University University of the Sunshine Coast University of York Flamingo Land Ltd. Sommersbergseestrasse Ghent University CAVElab Ghent University Royal Museum for Central Africa - Service of Wood Biology Isotope Bioscience Laboratory-ISOFYS Ghent University Gembloux Agro-Bio Tech Université de Liege Landscape Ecology and Vegetal Production Systems Unit CAVElab Computational & Applied Vegetation Ecology Ghent University Tropical Forestry Forest Resources Management Gembloux Agro-Bio Tech University of Liege Université Libre de Bruxelles (ULB) Evolutionary Biology and Ecology Royal Museum for Central Africa Royal Museum for Central Africa Ghent University Department of Environment Ghent University Service Evolution Biologique et Ecologie Belize Foundation for Research and Environmental Education IBIF Museo de Historia Natural Noel Kempff Mercado Universidad Autonoma Gabriel Rene Moreno PROMAB Museo Noel Kempff Consultor Independiente Jardin Botanico Municipal de Santa Cruz Museo de Historia Natural Noel Kempff Mercado Forest Management in Bolivia Universidad Autónoma del Beni Riberalta Museo de Historia Natural Noel Kempff Herbario del Sur de Bolivia Universidad Autónoma del Beni Conservation International Instituto de Biodiversidade e Floresta Universidade Federal do Oeste do Pará Universidade Federal de Pernambuco Universidade do Estado de Mato Grosso Universidade do Estado de Mato Grosso (UNEMAT) Projeto TEAM – Manaus Universidade Federal de Juiz de Fora (UFJF) Universidade Federal do Rio de Janeiro Instituto Nacional de Pesquisas da Amazônia Projeto Dinâmica Biológica de Fragmentos Florestais Departamento de Genética Ecologia e Evolução Universidade Federal de Minas Gerais Universidade Estadual de Campinas Laboratório de Ecologia de Comunidades e Funcionamento de Ecossistemas-ECoFERP Departamento de Biologia Faculdade de Filosofia Ciências e Letras USP National Institute for Space Research (INPE) Universidade Federal de Roraima (UFRR) UNESP - São Paulo State University Carbonozero Consultoria Ambiental Departamento de Biologia Universidade Federal do Amazonas (UFAM) Centro de Energia Nuclear na Agricultura Universidade de São Paulo UERR - Campus Rorainópolis Universidade Federal do Acre Instituto Agronômico de Campinas Universidade Federal do Rio Grande do Sul Embrapa Universidade Estadual do Norte Fluminense (UENF) Universidade Federal da Bahia (UFBA) Instituto de Biologia Universidade Estadual de Campinas Universidade Federal do Piauí (UFPI) Botany and Plant Ecology Laboratory Federal University of Acre INPA- Instituto Nacional de Pesquisas da Amazônia UERR - Campus Boa Vista Universidade Federal do Ceará Universidade Federal de Campina Grande Universidade Federal do Para Núcleo de Estudos e Pesquisas Ambientais Universidade Estadual de Campinas Instituto Federal de Educação Ciência e Tecnologia do Acre Instituto de Pesquisas Jardim Botânico do Rio de Janeiro Universidade Federal do Oeste do Pará UEFS Depto. de Ciências Biológicas Universidade Federal do Agreste de Pernambuco (UFAPE) Universidade Estadual de Montes Claros FFCLRP-USP/Br UNEMAT Universidade Federal de Jataí Universidade Federal do Pará Instituto de Ciências Biológicas Universidade de Campinas Universidade Federal de Lavras (UFLA) Museu Goeldi Embrapa Amazônia Oriental Instituto Nacional de Pesquisas da Amazônia UFMG - Universidade Federal de Minas Gerais Fundação Universidade Fedral de Rondônia - UNIR INPA- Instituto Nacional de Pesquisas Amazônicas Instituto Nacional de Pesquisas da Amazônia - Coordenação de Pesquisas em Silvicultura Tropical Jardim Botânico do Rio de Janeiro National Institute for Research in Amazonia Universidade Federal de Roraima (UFRR/PRONAT) Universidade Estadual de Campinas/UNICAMP Instituto Nacional de Pesquisas da Amazônia/CPBO Universidade Federal de Santa Catarina (UFSC) INCAPER- Instituto Capixaba de Pesquisa Assistência Técnica e Extensão Rural INPE- Instituto Nacional de Pesquisas Espaciais Universidade de São Paulo Instituto de Biociências Universidade Estadual Paulista Semiarid National Institute (INSA) Universidade de Brasília Departamento de Engenharia Florestal IBAM - Instituto Bem Ambiental Universidade do Estado de Mato Grosso Campus de Nova Xavantina University in Campinas Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF) LMF Instituto Nacional de Pesquisas da Amazônia Universidade Federal do Vale do São Francisco USP - University of São Paulo Instituto Federal do Espírito Santo (IFES) INPA - Instituto Nacional de Pesquisas da Amazônia Grupo MAUA Universidade Federal de Mato Grosso Instituto de Ciências Naturais Humanas e Sociais Instituto Nacional da Mata Atlântica RAINFOR-PPBIO Universidade Federal Rural da Amazônia - UFRA/CAPES Universidade Federal do Amazonas (UFAM) INPA/Max-Planck Project EMBRAPA- Empresa Brasileira de Pesquisa Agropecuária (Amazônia Oriental) Serviço Florestal Brasileiro Museu Universitário Universidade Federal do Acre Universidade Federal Rural de Pernambuco PUCPR - Pontifícia Universidade Católica do Paraná Museu Paraense Emilio Goeldi Universiti Brunei Darussalam Environmental and Life Sciences Faculty of Science Universiti Brunei Darussalam Institute for Biodiversity and Environmental Research Universiti Brunei Darussalam Plant Systematic and Ecology Laboratory Department of Biology Higher Teachers’ Training College University of Yaounde I Faculty of Science Department of Botany and Plant Physiology University of Buea Faculty of Science Department of Plant Science University of Buea National Herbarium Plant Systematics and Ecology Laboratory Higher Teachers’ Training College University of Yaoundé I Department of Plant Biology Faculty of Sciences University of Yaounde 1 Bioversity International Faculty of Forestry University of Toronto Ministère des Eaux Forêts Chasse et Pêche (MEFCP) Universidad Católica de la Santísima Concepción Universidad de La Serena Research Institute of Tropical Forestry Chinese Academy of Forestry Kunming Institute of Botany Chinese Academy of Sciences Beijing Forestry University Universidad Nacional Abierta y a Distancia Red COL-TREE Corporación COL-TREE Nuevo Estándar Biotropical NEBIOT SAS Universidad del Tolima Asociación GAICA Universidad de Nariño – Red BST-Col Parques Nacionales Naturales Territorial Caribe – Red BST-Col Universidad del Atlantico – Red BST-Col Departamento de Ciencias Forestales Universidad Nacional de Colombia - Sede Medellín Socioecosistemas y Clima Sostenible Fundacion con Vida Parques Nacionales Naturales de Colombia – Red BST-Col Instituto de Investigación de Recursos Biológicos Alexander von Humboldt – Red BST-Col UNAL Instituto de Investigación Recursos Biologicos Alexander von Humboldt – Red BST-Col Fundación Jardín Botánico de Medellín Herbario “Joaquín Antonio Uribe” (JAUM) – Red BST-Col Universidad Nacional de Colombia sede Amazonia Coltree Facultad del Medio Ambiente y Recursos Naturales Universidad Distrital Francisco José de Caldas – Red BST-Col Universidad de Tolima Fundación Orinoquia Biodiversa – Red BST-Col Departamento de Biología Facultad de Ciencias Naturales Universidad Icesi – Red BST-Col Instituto de Ciencias Naturales Universidad Nacional de Colombia Universidad de los Llanos Servicios Ecoysistemicos y Cambio Climatico (SECC) Fundación Con Vida & Corporación COL-TREE Universidad del Rosario Fundacion Ecosistemas Secos de Colombia – Red BST-Col Universidad de los Andes - ANDES herbarium Institute of Botany Czech Academy of Sciences Palacky University Czech University of Life Sciences Mendel University World Wide Fund for Nature Wildlife Conservation Society-DR Congo Lukuru Wildlife Research Foundation Université de Kisangani Faculté des Sciences Laboratoire d'écologie et aménagement forestier Université de Kisangani Université de Kisangani Faculté des Sciences Agronomiques République Démocratique du Congo Ministère de l'Environnement et Développement Durable Aarhus University University of Copenhagen Escuela Politécnica Nacional del Ecuador Herbario Alfredo Paredes (QAP) Universidad Central del Ecuador Universidad Técnica Particular de Loja Grupo de Investigación en Biodiversidad Medio Ambiente y Salud-BIOMAS Universidad de las Américas, Campus Queri Keller Science Action Center The Field Museum, 1400 South Lake Shore Dr. Universidad Estatal Amazónica Facultad de Ingeniería Ambiental Universidad Tecnica del Norte Herbario Nacional del Ecuador Grupo de Ecosistemas Tropicales y Cambio Global Universidad Regional Amazónica ikiam Colegio de Ciencias Biológicas y Ambientales COCIBA & Extensión Galápagos Universidad San Francisco de Quito-USFQ Herbario de Botánica Económica del Ecuador QUSF Universidad San Francisco de Quito USFQ Galapagos Science Center USFQ UNC Chapel Hill University of North Carolina-UNC Chapel Hill University of Florida FindingSpecies Mekelle University Environment Climate Change and Coffee Forest Forum (ECCCFF) University of Turku Centre de coopération International en Recherche Agronomique pour le Développement (CIRAD) CNRS ONF INRAE Centre National de la Recherche Scientifique AMAP Univ Montpellier IRD CNRS CIRAD INRA Forêts et Sociétés (F&S) Centre de coopération International en Recherche Agronomique pour le Développement (CIRAD) Departement Hommes Natures Societes Museum national d'histoire naturelle INRA Cirad UMR Ecologie des Forêts de Guyane (AgroparisTech CNRS INRAE Université des Antilles Université de la Guyane) Ministry of Forests Seas Environment and Climate Rougier-Gabon Agence Nationale des Parcs Nationaux Gabon Commission of Central African Forests (COMIFAC) Agence Nationale des Parcs Nationaux Ministère des Forêts des Eaux de la Mer de l'Environnement Chargé du Plan Climat des Objectifs de Développement Durable et du Plan d'Affectation des Terres Institut de Recherche en Ecologie Tropicale (CENAREST) Gabon/Agence Nationale des Parcs Nationaux Georg-August-University Göttingen University of Freiburg Institute of Botany University of Hohenheim Max Planck Institute for Chemistry Forestry Research Institute of Ghana (FORIG) Mensuration Unit Forestry Commission of Ghana Center for International Forestry Research Iwokrama International Centre for Rainforest Conservation and Development Guyana Forestry Commission Utrecht University Centre for Sustainable Technologies Indian Institute of Science Centre for International Forestry Research (CIFOR) Herbarium Borgoriense Indonesian Institute of Sciences (LIPI) Indonesian Institute of Science Forest Research and Development Agency (FORDA) Balitek-KSDA Samboja University of Florence and MUSE - Museo delle Scienze Cirad Hokkaido University Graduate School of Agriculture Kyoto University Forestry Development Authority of the Government of Liberia (FDA) University of Liberia Sungai Wain Protection Forest South East Asia Rainforest Research Partnership Danum Valley Field Centre Malaysian Palm Oil Board Sabah Forestry Department Forest Research Centre Universiti Malaysia Sabah Sabah Forestry Department Sarawak Forestry Corporation Eduardo Mondlane University Herbarium UNAN-Leon Universidad Nacional Autónoma de Nicaragua University of Abeokuta Natural History Museum of Norway University of Oslo Norwegian University of Life Sciences Universidad Nacional de la Amazonía Peruana (UNAP) Universidad Nacional de Jaén Jardin Botanico de Missouri Andes to Amazon Biodiversity Program Universidad Nacional de San Agustín de Arequipa Facultad de Ciencias Biológicas Universidad Nacional de la Amazonía Peruana Kené - Instituto de Estudios Forestales y Ambientales Instituto de Investigaciones de la Amazonia Peruana (IIAP) Universidad Nacional Jorge Basadre de Grohmann (UNJBG) Universidad Nacional de San Antonio Abad del Cusco Centro de Conservación Investigación y Manejo CIMA Pontificia Universidad Católica del Perú Asociacion Bosques Perú Université Officielle de Bukavu Université Marien N'Gouabi Wildlife Conservation Society Ecole Nationale Supérieure d'Agronomie et de Foresterie Université Marien Ngouabi Univeriste Marien Ngouabi The Gola Rainforest National Park Department of Geography National University of Singapore Departamento de Biología y Geología Física y Química inorgánica Universidad Rey Juan Carlos Real Jardín Botánico – CSIC Departamento de Biología Área de Botánica Universidad Autónoma de Madrid Museo Nacional de Ciencias Naturales (MNCN-CSIC) Centre for Agricultural Research in Suriname (CELOS) Stockholm Environment Institute Department of Plant Ecology and Evolution Uppsala University Southern Swedish Forest Research Centre InfoFlora Conservatoire et Jardin Botanique Geneve National Chung Hsing University Sokoine University of Agriculture Naturalis Biodiversity Center Wageningen University Forest Ecology and Forest Management Group Tropenbos International Institute for Biodiversity and Ecosystem Dynamics University of Amsterdam Bureau Waardenburg BV Van Hall Larenstein University of Applied Sciences Van der Hout Forestry Consulting Utrecht University, Domplein 29 Wageningen University Plant Ecology and Nature Conservation Group Data for Sustainability Department of Zoology Entomology & Fisheries Sciences Makerere University The Institute of Tropical Forest Conservation (ITFC) Mbarara University of Science and Technology (MUST) George Washington University Makerere University Department of Forestry Biodiversity and Tourism Makerere University University of Stirling University of Kent School of Geography University of Leeds UK Centre of Ecology & Hydrology Lancaster University University of Oxford The Landscapes and Livelihoods Group (TLLG) Overseas Development Institute Manchester Metropolitan University University of Aberdeen University of Exeter School of GeoSciences University of Edinburgh University of Cambridge Department of Environment and Geography University of York Department of Geography University College London Imperial College School of Geography Earth & Environmental Sciences Birmingham Institute of Forest Research University of Birmingham University of Plymouth Geography College of Life and Environmental Sciences University of Exeter Lancaster Environment Centre Lancaster University University of Edinburgh School of Biology University of Leeds Royal Botanic Garden Edinburgh CENAREST & ANPN & Stirling University University of Bristol School of Biological Sciences Department of Plant Sciences University of Cambridge Living with Lake Centre Laurentian University Royal Botanic Gardens Kew The Royal Society for the Protection of Birds centre for Conservation Science Environmental Change Institute School of Geography and the Environment University of Oxford UK Centre for Ecology & Hydrology School of Geography and the Environment University of Oxford The Royal Botanic Gardens Department of Geography and Environmental Science University of Dundee School of Biological Sciences University of Southampton University of East Anglia Stirling University School of Earth and Environment University of Leeds Department of Plant & Soil Science School of Biological Sciences University of Aberdeen, Cruickshank Building Institute for Transport Studies University of Leeds UK Research & Innovation University of Nottingham University of Bangor Center for Tropical Research Institute of the Environment and Sustainability University of California Center for Tropical Conservation Nicholas School of the Environment Duke University Ecology and Evolutionary Biology University of Michigan Saint Louis Zoo Department of Organismic and Evolutionary Biology Harvard University Center for Global Discovery and Conservation Science Arizona State University Wildlife Conservation Society – Programme Congo Woods Hole Research Center The University of Michigan Herbarium Nicholas School of the Environment National Park Service University of California ForestGEO Smithsonian Tropical Research Institute University of Texas at Austin Smithsonian Institute Washington University in Saint Louis Center for Conservation and Sustainable Development at the Missouri Botanical Garden Smithsonian Tropical Research Institute Smithsonian Institution Forest Global Earth Observatory (ForestGEO) Forest Global Earth Observatory (ForestGEO) Smithsonian Tropical Research Institute George Mason University Missouri Botanical Garden Broward County Parks and Recreation Nova Southeastern University Science and Education The Field Museum Department of Biology Boston University Wake Forest University Department of Geographical Sciences University of Maryland San Diego Zoo Institute for Conservation Research Biology Department Washington State University Yale School of Forestry & Environmental Studies Columbia University Department of Environmental Science Policy and Management University of California Berkeley School of Earth Sciences and Environmental Sustainability Northern Arizona University Department of Geography and the Environment University of Texas at Austin UNELLEZ-Guanare Programa de Ciencias del Agro y el Mar Herbario Universitario (PORT) Ci Progress GreenLife Universidad Nacional Experimental de Guayana Instituto Venezolano de Investigaciones Científicas (IVIC) Universidad de los Andes Viet Nature Conservation Centre CIRAD School of Life Sciences University of Lincoln UNESP - São Paulo State University Instituto de Biociências Universidade Estadual Paulista Gordon and Betty Moore Foundation: 1656 FAPESP: 2012/51509-8 FAPESP: 2012/51872-5 Fundação de Amparo à Pesquisa do Estado de Goiás: 2017/10267000329 European Research Council: 291585 Gordon and Betty Moore Foundation: 5349 European Research Council: 758873 Belgian Federal Science Policy Office: BR/132/A1/AFRIFORD Belgian Federal Science Policy Office: BR/143/A3/HERBAXYLAREDD Vlaamse Interuniversitaire Raad: CD2018TEA459A103 CNPq: CNPq/PPBio/457602/2012-0 National Science Foundation: DEB 1754647 Natural Environment Research Council: E/M0022021/1 Royal Society: ICA/R1/180100 Natural Environment Research Council: NE/D005590/1 European Research Council: NE/F005806/1 Natural Environment Research Council: NE/F005806/1 FAPESP: NE/K016431/1 Natural Environment Research Council: NE/N004655/1 FAPESP: NE/N012542/1 Royal Society: NE/P008755/1 FAPESP: NE/S011811/1 National Geographic Society: NE/T01279X/1 CNPq: PELD/441244/2016-5 Belgian Federal Science Policy Office: SD/AR/01A/COBIMFO

Introduction. En raison de la diminution des ressources en bois d’œuvre tropicaux, il convient d\'améliorer les connaissances sur les espèces ligneuses en vue de développer des politiques d\'exploitation réellement durables. Reconnu pour la grande qualité de son bois, Cylicodiscus gabunensis Harms (Fabaceae-Caesalpinioideae) est une essence à haute valeur socio-économique. Cet article dresse la synthèse bibliographique des connaissances relatives à cette espèce en vue de mettre en avant l’ensemble des aspects méritant des investigations scientifiques approfondies.Littérature. Commercialisée sous le nom d’okan, C. gabunensis est une espèce ligneuse non grégaire vivant dans les forêts denses humides tropicales sempervirentes et semi-décidues. Arbre fétiche pour certains peuples autochtones, C. gabunensis est utilisé par les communautés rurales pour de multiples usages. C’est une espèce à phénologie régulière avec une dispersion anémochore des graines. Les populations d’arbres affichent un déficit de régénération en forêt dense humide sempervirente, ce qui compromettrait l’exploitation de l’espèce à long terme. Ce risque est accru par le manque évident d’informations écologiques et sylvicoles permettant une gestion durable.Conclusions. Cette revue bibliographique résume l’ensemble des informations disponibles sur C. gabunensis principalement en botanique, anatomie du bois, écologie et ethnobotanique. Elle renseigne sur l’état actuel des connaissances au regard des rythmes d’exploitation et de l’état des populations de l’espèce. Des informations complémentaires sont nécessaires pour (i) statuer sur la conservation des populations de l’espèce et (ii) proposer des stratégies de gestion adaptées., Cylicodiscus gabunensis Harms: a popular species in international trade. A reviewIntroduction. Due to the decline in tropical timber resources, silvicultural and ecological knowledge in these taxa need to be improved for management decision-making. Cylicodiscus gabunensis Harms (Fabaceae-Caesalpinioideae) is a timber tree species with a high socio-economic value. The present paper provides a species-specific literature review and highlights research areas for future investigations.Literature. Known as okan, C. gabunensis inhabits evergreen and semi-deciduous tropical rain forests. Considered as a sacred tree by indigenous peoples, it is a multipurpose timber tree species. The phenology of this species is regular and its seeds are dispersed by wind. Nowadays, most C. gabunensis populations found in evergreen forests exhibit a clear lack of regeneration, which may threaten its long-term logging. The lack of other relevant silvicultural and ecological information for forest managers may increase that risk of unsustainable exploitation.Conclusions. This review summarizes the information available on C. gabunensis in the fields of botany, wood anatomy, ecology and ethnobotany. It provides valuable information for forest managers and decision-makers while considering exploitation intensities and tree population characteristics. Highlighting this information is the first step to (i) deciding on a conservation status for the species, and (ii) proposing appropriate management strategies.

Introduction. Cet article propose une synthèse des connaissances actuelles sur la classification, l’écologie et la biologie des céphalophes des forêts denses humides d’Afrique centrale (genres Cephalophus et Philantomba). Il fait aussi le point sur les pressions anthropiques subies par ces mammifères terrestres. Littérature. De nombreuses publications sur les céphalophes vivant dans les forêts denses humides d’Afrique centrale se focalisent sur la chasse, qu’elle soit de subsistance ou commerciale, y compris le braconnage. La classification taxonomique des céphalophes ayant été récemment révisée, de nouvelles espèces ont été décrites, alors que leur écologie n’est que très peu documentée. Cette synthèse met en exergue les déficits en termes de connaissances scientifiques et propose les thématiques prioritaires pour de futures recherches.Conclusions. Bien que de nombreux domaines restent à explorer pour certaines espèces (utilisation de l’habitat, domaine vital, etc.), il est suggéré d’étudier en priorité les techniques de différenciation des espèces de céphalophes lors des inventaires, leur rôle dans la dynamique forestière et l’impact de l’exploitation forestière sur leurs populations., State of knowledge on duikers (genera Cephalophus and Philantomba) of central Africa rainforests. A reviewIntroduction. This article provides a synthesis of current knowledge on classification, ecology and biology of duikers living in central African rainforests (genera Cephalophus and Philantomba). It also provides an update on the anthropogenic pressures on these terrestrial mammals. Literature. Many publications on central African duikers are focused on subsistence or commercial hunting, and poaching. As the taxonomic classification of duikers has recently been revised, new species have been described with very little information available on their ecology. This synthesis highlights the gaps in the scientific knowledge and proposes priority themes for future research.Conclusions. Although many aspects remain to be explored for some species (i.e., habitat use, home range), it is suggested to investigate in priority: the inventory methods, the role of duikers in forest dynamics, and the impact of logging on their populations.

En Afrique, les plantations d'arbres sont amenées à se développer pour plusieurs raisons : restauration des capacités de production et des services rendus par les forêts naturelles, valorisation des terres agroforestières, récolte plus aisée du bois et des produits forestiers non ligneux, etc. Les espèces exotiques n'offrant que des services spécifiques, il importe de redynamiser la plantation d'espèces locales. C'est l'objet de ce guide, qui s'est focalisé sur les essences des forêts denses humides, en capitalisant des résultats d'essais passés ou récents de six pays africains, et en mobilisant des compétences et connaissances individuelles. L'ouvrage aborde de façon pratique les différentes étapes d'un programme sylvicole : récolte et gestion des semences, construction et gestion des pépinières, modalités d'installation et de conduite des plantations. Une estimation des coûts et de la rentabilité de telles plantations est également fournie. Enfin, le livre décrit en détail l'itinéraire sylvicole de 50 espèces d'arbres des forêts denses humides africaines. Ce guide est destiné à un large public : gestionnaires, aménagistes, techniciens et ingénieurs forestiers, étudiants et scientifiques intéressés par la sylviculture tropicale.

Aim: Tree crowns determine light interception, carbon and water exchange. Thus, understanding the factors causing tree crown allometry to vary at the tree and stand level matters greatly for the development of future vegetation modelling and for the calibration of remote sensing products. Nevertheless, we know little about large-scale variation and determinants in tropical tree crown allometry. In this study, we explored the continental variation in scaling exponents of site-specific crown allometry and assessed their relationships with environmental and stand-level variables in the tropics. Location: Global tropics. Time period: Early 21st century. Major taxa studied: Woody plants. Methods: Using a dataset of 87,737 trees distributed among 245 forest and savanna sites across the tropics, we fitted site-specific allometric relationships between crown dimensions (crown depth, diameter and volume) and stem diameter using power-law models. Stand-level and environmental drivers of crown allometric relationships were assessed at pantropical and continental scales. Results: The scaling exponents of allometric relationships between stem diameter and crown dimensions were higher in savannas than in forests. We identified that continental crown models were better than pantropical crown models and that continental differences in crown allometric relationships were driven by both stand-level (wood density) and environmental (precipitation, cation exchange capacity and soil texture) variables for both tropical biomes. For a given diameter, forest trees from Asia and savanna trees from Australia had smaller crown dimensions than trees in Africa and America, with crown volumes for some Asian forest trees being smaller than those of trees in African forests. Main conclusions: Our results provide new insight into geographical variability, with large continental differences in tropical tree crown allometry that were driven by stand-level and environmental variables. They have implications for the assessment of ecosystem function and for the monitoring of woody biomass by remote sensing techniques in the global tropics.

The idea that tropical forest and savanna are alternative states is crucial to how we manage these biomes and predict their future under global change. Large-scale empirical evidence for alternative stable states is limited, however, and comes mostly from the multimodal distribution of structural aspects of vegetation. These approaches have been criticized, as structure alone cannot separate out wetter savannas from drier forests for example, and there are also technical challenges to mapping vegetation structure in unbiased ways. Here, we develop an alternative approach to delimit the climatic envelope of the two biomes in Africa using tree species lists gathered for a large number of forest and savanna sites distributed across the continent. Our analyses confirm extensive climatic overlap of forest and savanna, supporting the alternative stable states hypothesis for Africa, and this result is corroborated by paleoecological evidence. Further, we find the two biomes to have highly divergent tree species compositions and to represent alternative compositional states. This allowed us to classify tree species as forest vs. savanna specialists, with some generalist species that span both biomes. In conjunction with georeferenced herbarium records, we mapped the forest and savanna distributions across Africa and quantified their environmental limits, which are primarily related to precipitation and seasonality, with a secondary contribution of fire. These results are important for the ongoing efforts to restore African ecosystems, which depend on accurate biome maps to set appropriate targets for the restored states but also provide empirical evidence for broad-scale bistability., SCOPUS: ar.j, info:eu-repo/semantics/published

Aim Tree crowns determine light interception, carbon and water exchange. Thus, understanding the factors causing tree crown allometry to vary at the tree and stand level matters greatly for the development of future vegetation modelling and for the calibration of remote sensing products. Nevertheless, we know little about large-scale variation and determinants in tropical tree crown allometry. In this study, we explored the continental variation in scaling exponents of site-specific crown allometry and assessed their relationships with environmental and stand-level variables in the tropics.Location Global tropics.Time period Early 21st century.Major taxa studied Woody plants.Methods Using a dataset of 87,737 trees distributed among 245 forest and savanna sites across the tropics, we fitted site-specific allometric relationships between crown dimensions (crown depth, diameter and volume) and stem diameter using power-law models. Stand-level and environmental drivers of crown allometric relationships were assessed at pantropical and continental scales.Results The scaling exponents of allometric relationships between stem diameter and crown dimensions were higher in savannas than in forests. We identified that continental crown models were better than pantropical crown models and that continental differences in crown allometric relationships were driven by both stand-level (wood density) and environmental (precipitation, cation exchange capacity and soil texture) variables for both tropical biomes. For a given diameter, forest trees from Asia and savanna trees from Australia had smaller crown dimensions than trees in Africa and America, with crown volumes for some Asian forest trees being smaller than those of trees in African forests.Main conclusions Our results provide new insight into geographical variability, with large continental differences in tropical tree crown allometry that were driven by stand-level and environmental variables. They have implications for the assessment of ecosystem function and for the monitoring of woody biomass by remote sensing techniques in the global tropics.

The dating of diversification events, including transitions between biomes, is key to elucidate the processes that underlie the assembly and evolution of tropical biodiversity. Afzelia is a widespread genus of tropical trees, threatened by exploitation for its valuable timber, that presents an interesting system to investigate diversification events in Africa. Africa hosts diploid Afzelia species in the savannahs north and south of the Guineo-Congolian rainforest and autotetraploid species confined to the rainforest. Species delimitation and phylogenetic relationships among the diploid and tetraploid species remained unresolved in previous studies using small amounts of DNA sequence data. We used genotyping-by-sequencing in the five widespread Afzelia species in Africa, the savannah species A. africana and A. quanzensis and the rainforest species A. bipindensis, A. pachyloba, and A. bella. Maximum likelihood and coalescent approaches resolved all species as monophyletic and placed the savannah and rainforest taxa into two separate clades corresponding to contrasted ploidy levels. Our data are thus compatible with a single biome shift in Afzelia in Africa, although we were unable to conclude on its direction. SNAPP calibrated species trees show that the savannah diploids started to diversify early, at 12 (9.09–14.89) Ma, which contrasts with a recent and rapid diversification of the rainforest tetraploid clade, starting at 4.22 (3.12 – 5.36) Ma. This finding of older diversification in a tropical savannah clade vs. its sister rainforest clade is exceptional; it stands in opposition to the predominant observation of young ages for savannahs lineages in tropical regions during the relatively recent expansion of the savannah biome., SCOPUS: ar.j, info:eu-repo/semantics/published

The sensitivity of tropical forest carbon to climate is a key uncertainty in predicting global climate change. Although short-term drying and warming are known to affect forests, it is unknown if such effects translate into long-term responses. Here, we analyze 590 permanent plots measured across the tropics to derive the equilibrium climate controls on forest carbon. Maximum temperature is the most important predictor of aboveground biomass (−9.1 megagrams of carbon per hectare per degree Celsius), primarily by reducing woody productivity, and has a greater impact per °C in the hottest forests (>32.2°C). Our results nevertheless reveal greater thermal resilience than observations of short-term variation imply. To realize the long-term climate adaptation potential of tropical forests requires both protecting them and stabilizing Earth's climate.

L’intelligence des arbres est un sujet qui passionne les populations urbaines. Elle fait l’objet d’un débat animé entre les différents acteurs du secteur forestier. La présente note vise à objectiver ce débat en synthétisant les connaissances récentes sur le sujet. Elle montre que les arbres peuvent communiquer entre eux, soit via des molécules volatiles, soit via des échanges souterrains, notamment grâce à un réseau mycorhizien. Les arbres peuvent aussi percevoir la lumière et les sons. Ils peuvent donc s’adapter à un environnement changeant, ce qui traduit une certaine forme d’intelligence. Néanmoins, renoncer à l’exploitation du bois sur cette base ne peut être justifié. Cela se traduirait par des impacts environnementaux dont la portée est occultée par les détracteurs de l’exploitation forestière., Palaver around the trees: discussions about their intelligence to the drifts of anthropomorphismThe intelligence of trees is an issue that fascinates people in urban areas. It is the subject of passionate debate between forest sector stakeholders. This article aims to objectify this debate by synthesizing recent knowledge on the subject. It shows that trees can communicate with each other, either via volatile molecules or via underground exchanges, in particular through a mycorrhizal network. Trees can also perceive light and sound. They can therefore adapt to a changing environment, which reflects a certain form of intelligence. Nevertheless, abandoning timber logging for this reason is not acceptable. This would result in environmental impacts that are often overlooked by the opponents of logging.

Introduction. De nos jours, la gestion des ressources forestières ne se focalise plus sur l’exploitation exclusive du bois d’œuvre, mais prend également en considération les produits forestiers non ligneux. Entandrophragma cylindricum (Sprague) Sprague, de son nom commercial « sapelli/sapele », de la famille des Meliaceae, illustre parfaitement cette situation. Le présent article fait un état de l’art des connaissances concernant E. cylindricum et présente quelques informations sur la chenille qui lui est inféodée.Littérature. Le sapelli est une des espèces ligneuses les plus exploitées d’Afrique centrale pour son bois d’œuvre. Il est répandu dans la forêt dense humide semi-caducifoliée du domaine guinéo-congolais. C’est une espèce semi-héliophile, son mode de dispersion est anémochore et sa phénologie est régulière. Selon la sylviculture appliquée, sa croissance en diamètre peut atteindre jusque 0,82 cm par an. Cette essence est également l’hôte d’une espèce de chenille comestible riche en protéines, Imbrasia oyemensis Rougeot. Fortement appréciée par les populations locales, cette chenille fait également l’objet d’un commerce régional et international. Enfin, l’écorce du sapelli est reconnue pour son intérêt ethnobotanique, particulièrement en médecine traditionnelle.Conclusions. Les informations tirées de la littérature ont permis de mettre en évidence certaines lacunes relatives à l’écologie et au mode de reproduction de cette espèce et, ceci, en dépit de son importance pour le commerce du bois. De plus, les inconnues quant à la productivité et la saisonnalité des chenilles d’Imbrasia oyemensis sur cet arbre nécessitent de développer des recherches complémentaires pour garantir la durabilité de l’exploitation simultanée de la ressource ligneuse et non ligneuse et pour proposer des modes de gestion concertés entre exploitants industriels et populations locales., Entandrophragma cylindricum (Sprague) Sprague (Meliaceae), a competitive tree species in Central Africa. A reviewIntroduction. Nowadays, the management of forest resources is no longer focused on the exclusive extraction of timber; it must also consider the use and management of non-timber forest products. Entandrophragma cylindricum (Sprague) Sprague, whose trade name is “sapelli/sapele”, and which belongs to the Meliaceae family, perfectly illustrates this issue. This article proposes an overview of the existing literature regarding E. cylindricum and presents some information on its host caterpillar.Literature. Sapele is among the most exploited tree species in Central Africa, due to its valuable timber. This tree is common in the semi-deciduous rainforest of the Guinean–Congolese domain. It is a non-pioneer, light-demanding species, its dispersal mode is anemochorous and the phenology is regular. Logging coupled with thinning boosts the diametric growth of individuals by up to 0.82 cm·year-1. Sapele is also the host of an edible caterpillar species that is rich in protein, Imbrasia oyemensis Rougeot. Highly appreciated by the local populations, this caterpillar is sought out for regional and international trade purposes. In addition, the bark of the sapele is renowned for its ethnobotanical properties, especially in traditional medicine.Conclusions. The information reviewed from the literature helped to highlight some gaps in the knowledge regarding the reproductive ecology of this species, despite its importance for the timber trade. In addition, the current lack of information regarding the productivity and the seasonality of caterpillars of I. oyemensis inhabiting this tree requires the development of complementary research to ensure the sustainability of timber and non-timber uses for sapele. In addition, it is important that such improved silvicultural techniques involve concerted management interventions between logging companies and the local populations.

Few studies have addressed the evolutionary history of tree species from African savannahs at large geographic scales, particularly in the southern hemisphere (Zambezian region). Afzelia (Fabaceae: Caesalpinioideae) contains economically important timber species, including two species widely distributed in African savannahs: A. africana in the Sudanian region and A. quanzensis in the Zambezian region. To characterize the population genetic diversity and structure of these two species across their distribution ranges, we used nuclear microsatellites (simple sequence repeats, SSRs) and genotyping-by-sequencing (GBS) markers. Six SSR loci were genotyped in 241 A. africana and 113 A. quanzensis individuals, while 2,800 and 3,841 high-quality single nucleotide polymorphisms (SNPs) were identified in 30 A. africana and 12 A. quanzensis individuals, respectively. Both species appeared to be outcrossing (selfing rate ~ 0%). The spatial genetic structure was consistent with isolation-by-distance expectations based on both SSR and SNP data, suggesting that gene dispersal is spatially restricted in both species (bLd (SSR)= −0.005 and −0.007 and bLd (SNP)= −0.008 and −0.006 for A. africana and A. quanzensis, respectively). Bayesian clustering of SSR genotypes failed to identify genetic structure within species. In contrast, SNP data resolved intraspecific genetic clusters in both species, illustrating the higher resolving power of GBS at shallow levels of divergence. However, the clusters identified by SNPs revealed low levels of differentiation and no clear geographical entities. These results suggest that, although gene flow has been restricted over short distances in both species, populations have remained connected throughout the large, continuous Savannah landscapes. The absence of clear phylogeographic discontinuities, also found in a few other African savannah trees, indicates that their distribution ranges have not been significantly fragmented during past climate changes, in contrast to patterns commonly found in African rainforest trees.

1.Architectural traits that determine the light captured in a given environment are an important aspect of the life‐history strategies of tropical tree species. In this study, we examined how interspecific variation in architectural traits is related to the functional traits of 45 coexisting tree species in central Africa. 2.At the tree level, we measured tree diameter, total height and crown dimensions for an average of 30 trees per species (range 14–72, total 968 trees) distributed over a large range of diameters (up to 162 cm). Using log‐log models, we fitted species‐specific allometric relationships between tree diameter, height and crown dimensions. At the species level, we derived architectural traits (height and crown dimensions) at 15 cm and maximum diameters from species‐specific allometries. The architectural traits were then related to functional traits, including light requirements, wood density, leaf habit, and dispersal mode. 3.Among the 45 coexisting tree species, we identified strong variations in height and crown allometries, along with architectural traits derived from these species‐specific allometries. There was a positive correlation among architectural traits, suggesting that large‐statured canopy species were taller and had larger and deeper crowns than small‐statured understory species at all ontogenic stages. The relationships between architectural and functional traits highlighted a continuum of species between the large‐statured canopy species and the small‐statured understory species. In this moist and seasonal forest, large‐statured canopy species tended to be light‐demanding, wind‐dispersed, deciduous and large contributors to forest biomass (high basal area), while small‐statured understory species tended to be shade‐tolerant, animal‐dispersed, evergreen and most abundant in terms of stem density. 4.Our results highlighted strong architectural differences among coexisting tropical tree species in central Africa. The relationships between architectural and functional traits provided insights into the life‐history strategy of tropical tree species.