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6 results on '"Université deYaoundé I"'

1. Weighing trees with laser: vertical variations of wood specific gravity and their impacton volume-to-biomass conversion

Author

MOMO Takoudjou, Stephane, Ploton, Pierre, Boyemba, Faustin, Couteron, Pierre, Fayolle, A., Libalah, Moise, Loumeto, Joel, Medjibe, Vincent, Ngomanda, A., Nchama, A., Pélissier, Raphaël, Yongo, Olga, Rossi, Vivien, Takougoum Sagang, Le Bienfaiteur, Sonke, Bonaventure, Barbier, Nicolas, Université de Yaoundé I, 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]), Agence Nationale des Parcs Nationaux du Gabon, Université de Bangui, Forêts et Sociétés (UPR Forêts et Sociétés), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Plant Systematic and Ecology Laboratory (LaBosystE), Department of Biology, Higher Teachers’ Training College, Department of Biology, Higher Teachers Training College (HTTC), Université deYaoundé I, Université de Yaoundé, 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 Yaoundé I [Yaoundé], Biens et services des écosystèmes forestiers tropicaux : l'enjeu du changement global (Cirad-Es-UPR 105 BSEF), Département Environnements et Sociétés (Cirad-ES), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), and Agence Nationale des Parcs Nationaux du Gabon (ANPN)

Subjects
[SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, TLS, Terrestrial laser scanner, Weighing tree, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy
Abstract

International audience; Recent studies have shown the promising potential of terrestrial laser scanner (TLS) for theestimation of tree-and plot-level biovolumes. However, accurate and precise conversion of these volumes into AGB remains a big challenge. Here, we examined the implications of vertical variations of WSG on AGB estimations thanks to the destructive sampling of 821 trees from 51 species distributed across the Congo basin forests. We performed a principal component analysis (PCA)on the WSG of wood samples collected vertically along trees to characterize WSG vertical patterns. We further quantified errors associated to the use of species-level WSG extracted from Global Wood Density database (GWSG) when converting tree volume to biomass, and developed a simple correction model accounting for vertical variations. The two first PCA axes captured 78% of the variance in samples WSG and revealed the existence of increasing, constant and decreasing patterns of variation from tree stump tobranches that were well conserved within species. Vertical variation patterns could be predicted from WSG from tree stump as well as from GWSG. Using GWSG values to convert volumes to mass led to errors ranging from -40.31% to 72.77% at the tree level andca. 9% across trees. A simple model based on GWSG andtree diameter at breast height allowed drastically reducing the error (ca. 1.5% across trees). This study is an important step towards the standardization of a reliable AGB estimation method from TLS technology

Published
2019

2. A taxonomic revision of Angraecum section Dolabrifolia (Orchidaceae, Angraecinae), with the description of a new species from Gabon

Author

Murielle Simo-Droissart, Tariq Stévart, Porter P. Lowry, Bonaventure Sonké, Vincent Droissart, Daniel Geerinck, Université de Yaoundé I, Department of Biology, Higher Teachers Training College (HTTC), Université deYaoundé I, 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]), Université libre de Bruxelles (ULB), Missouri Botanical Garden, Institut de Systématique, Evolution, Biodiversité (ISYEB ), Muséum national d'Histoire naturelle (MNHN)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Herbarieum et Bibliothèque de Botanique africaine, Université de Yaoundé I [Yaoundé], 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 Libre de Bruxelles [Bruxelles] (ULB), Missouri Botanical Garden (USA), and Muséum national d'Histoire naturelle (MNHN)-École pratique des hautes études (EPHE)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)

Subjects
0106 biological sciences, 0301 basic medicine, IUCN Red List categories and criteria, Identification key, Monocots, Distribution map, Plant Science, Biology, categories and criteria, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, 010603 evolutionary biology, 01 natural sciences, 03 medical and health sciences, Monophyly, distribution map, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, identification key, Genus, Polyphyly, Angraecinae, West and Central Africa, IUCN Red List, Ecology, Evolution, Behavior and Systematics, Ecology, 15. Life on land, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, biology.organism_classification, 030104 developmental biology, Species richness, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Angraecum, Angraecoid orchids
Abstract

International audience; Despite a paucity of material available from continental Africa, previous morphological and molecular phylogenetic studies have suggested that Angraecum, the largest genus of the angraecoid orchids, is polyphyletic. A recent study based on broad sampling from the region confirmed the monophyly of section Dolabrifolia and a clear delimitation of four of its five members, one of which represents a new species. Based on these results, a comprehensive taxonomic revision of Angraecum sect. Dolabrifolia is presented here. It includes an identification key and a detailed description of each species, along with color photographs, distribution maps, information on habitat and phenology, and a preliminary risk of extinction assessment according to the IUCN Red List categories and criteria. Species richness in the section is highest in Atlantic Central Africa and around the Albertine Rift. The new species, A. biteaui, is described and illustrated with line drawings. It most closely resembles A. aporoides in general aspect but differs in both foliar and floral characters, and is only known from lowland forests in Gabon.

Published
2016
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3. Morphometrics and molecular phylogenetics of Angraecum section Dolabrifolia (Orchidaceae, Angraecinae)

Author

Gregory M. Plunkett, Porter P. Lowry, Murielle Simo-Droissart, Olivier J. Hardy, Vincent Droissart, Claire Micheneau, Tariq Stévart, Bonaventure Sonké, Université de Yaoundé I, Department of Biology, Higher Teachers Training College (HTTC), Université deYaoundé I, 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]), UFR des Sciences et Technologies, Université de La Réunion (UR), Institut de Systématique, Evolution, Biodiversité (ISYEB ), Muséum national d'Histoire naturelle (MNHN)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Missouri Botanical Garden, Laboratoire de Génétique et Ecologie Végétales, Université Libre de Bruxelles, Université de Bruxelles, New York Botanical Garden (NYBG), Herbarieum et Bibliothèque de Botanique africaine, Université libre de Bruxelles (ULB), Domein van Bouchout, National Botanic Garden of Belgium, Université de Yaoundé I [Yaoundé], 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]), Muséum national d'Histoire naturelle (MNHN)-École pratique des hautes études (EPHE)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Missouri Botanical Garden (USA), and Université Libre de Bruxelles [Bruxelles] (ULB)

Subjects
0106 biological sciences, 0301 basic medicine, food.ingredient, Angraecum distichum, Zoology, Angraecum aporoides, Plant Science, Angraecum podochiloides, Bayesian analyses, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, 010603 evolutionary biology, 01 natural sciences, Angraecum bancoense, 03 medical and health sciences, food, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Pectinaria, Angraecinae, Monophyly, Ecology, Evolution, Behavior and Systematics, biology, Continental Africa, 15. Life on land, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, biology.organism_classification, 030104 developmental biology, Molecular phylogenetics, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Angraecum, Angraecoid orchids, Morphometrics, Parsimony
Abstract

International audience; Species delimitation within Angraecum section Dolabrifolia is problematic due to morphological variability coupled with overlap in many of the characters traditionally used to distinguish species. Recent molecular phylogenetic studies of the genus included three of the five currently described species of the Dolabrifolia group, placing them as sister to continental African species of Angraecum sect. Pectinaria. In preparation for a taxonomic revision of section Dolabrifolia, we analyzed morphological and molecular data to re-assess the circumscription of each of the five currently described species, examined the relationships among members of the section, and assessed their position within the genus. We used 172 alcohol-preserved specimens to perform multivariate analyses on 15 morphological characters. We also collected molecular sequence data from 16 taxa including all members of the section using six DNA regions, and analyzed these data with parsimony and Bayesian methods. The morphometric study revealed five distinct groups, of which four correspond to currently recognized species, while the fifth represents a taxonomic novelty. Angraecum podochiloides is the most distinctive morphologically, recognizable by its narrow leaves bearing white-yellowish flowers. The often confused species Angraecum distichum and Angraecum bancoense are clearly distinguishable by flower size. Molecular phylogenetic analyses indicated that section Dolabrifolia forms a well-supported clade related to the continental African members of section Pectinaria. Four species are well delimited, while the accessions of Angraecum aporoides formed two well-supported clades corresponding to two subclusters revealed by the morphometric study. The recently published Angraecum poppendickianum is shown to be a synonym of A. distichum.

Published
2016
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4. Medicinal plants from the ouaddaï province (Chad): An ethnobotanical survey of plants used in traditional medicine

Author

Aouadalkarim Moussa Chahad, Ali B. Bechir, Marie-Geneviève Dijoux-Franca, Abdelsalam Tidjani, Bernard Aloys Nkongmeneck, Serge Michalet, Laboratoire d'Ecologie Microbienne - UMR 5557 (LEM), Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Vétérinaire de Lyon (ENVL)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Recherche Agronomique (INRA)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS), IUSTA, Laboratory Systematic and Ethnobotanical, Université deYaoundé I, Université des Sciences et de Technologie d'Ati (USTA), Faculté Science et Santé, Université Ndjamena, Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Ecole Nationale Vétérinaire de Lyon (ENVL), Ecologie microbienne ( EM ), Centre National de la Recherche Scientifique ( CNRS ) -Ecole Nationale Vétérinaire de Lyon ( ENVL ) -Université Claude Bernard Lyon 1 ( UCBL ), and Université de Lyon-Université de Lyon-Institut National de la Recherche Agronomique ( INRA ) -VetAgro Sup ( VAS )

Subjects
0106 biological sciences, Chad, [SDV]Life Sciences [q-bio], Ethnobotany, mesure thérapeutique, 01 natural sciences, 03 medical and health sciences, Combretaceae, Medicine, Medicinal plants, drug plant, Medicine, African Traditional, 2. Zero hunger, 0303 health sciences, Plants, Medicinal, biology, Traditional medicine, [ SDV ] Life Sciences [q-bio], business.industry, 030302 biochemistry & molecular biology, Fabaceae, 15. Life on land, biology.organism_classification, medicine.disease, tchad, 6. Clean water, Snake bites, 3. Good health, plante médicinale, Complementary and alternative medicine, médiation ethnobotanique, business, 010606 plant biology & botany
Abstract

Background/Objective: Plants are the basis of all health care systems. This study sought to inventory the most used medicinal plants in the local therapeutic patrimony of the Ouaddai (East Chad) through an ethnobotanical investigation. Methods: The inventory described the plant parts used, their mode of preparation, and their therapeutic uses. Results: Thirty-eight plants species are used for different purposes and diseases. The most used species belongs to the Mimosaceae (eight species), Caesalpiniaceae (four species), and Combretaceae (four species) families. The traditional medicinal uses, as well as the preparations, of these plants are diverse. The used parts are leaves (36.4%), peels (23.7%), fruits (18.2%), roots (10.9%), stems (5.5%), and other (5.3%). These plants are used to treat 16 different illnesses, notably amoebiasis (26.8%), respiratory infections (14.3%), fever (12.5%), kidney stones (7.1%), snake bites (7.1%), tooth decay (5.4%), and leprosy (5.4%). Conclusion: The results obtained from this survey constitute the starting point of an inventory of local medicinal plants to be completed by phytochemical, pharmacologic, and toxicologic studies to allow good exploitation of the local medicinal flora.

Published
2015
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5. Nutritional Composition of Five Varieties of Pap Commonly Consumed in Maroua (Far-North, Cameroon)

Author

Roger Ponka, Joëlle Léonil, Frédéric Gaucheron, Armand Abdou Bouba, Elie Fokou, Eric Beaucher, Michel Piot, Department of Agriculture, Livestock and Derivated Products, The Higher Institute of the Sahel, University of Maroua (UMa), Department of Biochemistry, Faculty of Science, Université deYaoundé I, Science et Technologie du Lait et de l'Oeuf (STLO), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)

Subjects
cereal, nutritional composition, allegation nutritionnelle, Potassium, Sodium, chemistry.chemical_element, lcsh:TX341-641, Maroua, chemistry.chemical_compound, céréale, aliment santé pour l'homme, pap, cameroun, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Dry matter, Far-North Cameroon, Food science, composition des aliments, pregnancy-associated protein, chemistry.chemical_classification, Nutrition and Dietetics, Methionine, micronutrimeny, Phosphorus, under-developed nations, afrique, pays en voie de développement, Amino acid, composition nutritionel, micronutriment, Human nutrition, chemistry, food nutrient content, Leucine, lcsh:Nutrition. Foods and food supply, [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition, Food Science
Abstract

The aim of this study was to determine the nutritional composition of five varieties of pap (cereal product) commonly consumed in Maroua, city of the Far-North Region of Cameroon. The proximate composition (moisture, ash, protein, lipid, and crude fibre) was determined by standard AOAC methods. Minerals (calcium, magnesium, sodium, potassium, iron, zinc, copper and manganese) were determined by atomic absorption spectrophotometry and phosphorus was determined colorimetrically. Amino acid composition was determined by ion-exchange chromatography. All the pap varieties had a very high carbohydrate content (79.47-85.29 g/100 g dry matter). Appreciable levels of phosphorus and potassium were recorded in all the pap varieties (137.5-231.0 mg/100 g dry matter and 198.20-322.22 mg/100 g dry matter, respectively). Consumption of each pap (100 g) by children 1-2 year old would meet 9.86-17.46% and 0.08-19.51% of their daily recommended intake respectively for protein and minerals. Leucine and glutamic acid were the most abundant essential amino acids and non-essential amino acids respectively in the pap. Essential amino acids in most of the pap samples met the recommended children requirement of the FAO/WHO/UNU for 1-2 year old children except methionine+cysteine and lysine.

Published
2015
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6. Characterizing the phylogenetic tree community structure of a protected tropical rain forest area in Cameroon

Author

Olivier J. Hardy, Stéphanie Manel, François Munoz, Pierre Couteron, Thomas L. P. Couvreur, Bonaventure Sonké, 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]), Laboratoire Population-Environnement-Développement (LPED), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU), Diversité, adaptation, développement des plantes (UMR DIADE), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Evolution Biologique et Ecologie, Université de Bruxelles, Department of Biology, Higher Teachers Training College (HTTC), Université deYaoundé I, Université de Yaoundé I [Yaoundé], 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 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]), and Université de Yaoundé I

Subjects
Plant Phylogenetics, 0106 biological sciences, Biodiversity, lcsh:Medicine, Plant Science, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, 01 natural sciences, Trees, Theoretical Ecology, Cameroon, lcsh:Science, Phylogeny, Species diversity, 0303 health sciences, Multidisciplinary, geography.geographical_feature_category, Ecology, Phylogenetic tree, Phylogenetic Analysis, Plants, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, Old-growth forest, Habitats, Phylogenetics, Community Ecology, Biologie, Conservation genetics, Research Article, Conservation of Natural Resources, Rainforest, Genetic Speciation, Biology, 010603 evolutionary biology, 03 medical and health sciences, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Evolutionary Systematics, Terrestrial Ecology, Transect, 030304 developmental biology, Taxonomy, Evolutionary Biology, geography, lcsh:R, Ecology and Environmental Sciences, Organisms, Biology and Life Sciences, 15. Life on land, Phylogenetic diversity, Threatened species, Conservation science, Biological dispersal, lcsh:Q, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

Tropical rain forests, the richest terrestrial ecosystems in biodiversity on Earth are highly threatened by global changes. This paper aims to infer the mechanisms governing species tree assemblages by characterizing the phylogenetic structure of a tropical rain forest in a protected area of the Congo Basin, the Dja Faunal Reserve (Cameroon). We re-analyzed a dataset of 11538 individuals belonging to 372 taxa found along nine transects spanning five habitat types. We generated a dated phylogenetic tree including all sampled taxa to partition the phylogenetic diversity of the nine transects into alpha and beta components at the level of the transects and of the habitat types. The variation in phylogenetic composition among transects did not deviate from a random pattern at the scale of the Dja Faunal Reserve, probably due to a common history and weak environmental variation across the park. This lack of phylogenetic structure combined with an isolation-bydistance pattern of taxonomic diversity suggests that neutral dispersal limitation is a major driver of community assembly in the Dja. To assess any lack of sensitivity to the variation in habitat types, we restricted the analyses of transects to the terra firme primary forest and found results consistent with those of the whole dataset at the level of the transects. Additionally to previous analyses, we detected a weak but significant phylogenetic turnover among habitat types, suggesting that species sort in varying environments, even though it is not predominating on the overall phylogenetic structure. Finer analyses of clades indicated a signal of clustering for species from the Annonaceae family, while species from the Apocynaceae family indicated overdispersion. These results can contribute to the conservation of the park by improving our understanding of the processes dictating community assembly in these hyperdiverse but threatened regions of the world. © 2014 Manel et al., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2014
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