Analyse Des Connaissances Sur Pterocarpus Erinaceus Poir. En Afrique Occidentale Et Centrale

Pterocarpus erinaceus (Fabaceae) est une arbre multiusage des zones sahéliennes et soudaniennes d’Afrique. L’espèce a fait l’objet de nombreuses études scientifiques très peu coordonnées, conduisant à des biais sur les besoins réels de connaissances devant permettre une bonne gestion et valorisation. Pour pallier cette insuffisance, les publications sur cette espèce ont été recherchées à partir de Google scholar, Bielefeld Academic Search Engine et Science direct. Après un filtre des publications trop généralistes, 127 publications réalisées entre 1974 et 2019 ont été retenues et classées suivant neuf thématiques préalablement identifiées. Les résultats, issus de 49 institutions de recherche provenant de 19 pays, montrent que les propriétés pharmacologiques, la caractérisation des peuplements de P. erinaceus et le rôle socio-économique sont les thématiques les plus abordées avec respectivement 41,7 %, 29,1 % et 16,5 % des publications alors que celles relatives aux techniques de multiplication, à la régénération et au rôle alimentaire sont peu abordées avec des fréquences respectives de 6,3 %, 4,7 % et 3,9 %. Les résultats indiquent également que 9 pays de l’Afrique de l’ouest totalisent plus de 84,2 % des publications contre de 3,2 % des publications effectuées par 2 pays de l’Afrique centrale et 12,6 % pour 8 pays européens. L’analyse a montré aussi que des études complémentaires sont nécessaires pour améliorer les connaissances sur les techniques de multiplication de l’espèce pour sa sylviculture et les facteurs qui influencent sa régénération en milieu naturel. Pterocarpus erinaceus (Fabaceae) is a multipurpose tree species of Sahelian and Sudanian zones in Africa. Tough the species has been actively studied, the lack of coordination and orientation in these studies lead to some biases in the knowledge needed for the better management and valorization of this species. To overcome this insufficiency, scientific publications available on the species were collected from Google scholar, Bielefeld Academic Search Engine (BASE) and Science direct portals. After filtering the generalist publications identified, 127 publications produced between 1974 and 2019 were classified according to nine previously identified themes. The results from 49 research institutions from 19 countries show that the pharmacological properties, the characteristics of the stands of P. erinaceus and the socioeconomic role are the most discussed themes with respectively 41.7 %, 29.1 % and 16.5 % of publications, while those relating to the propagation of the species, natural dissemination and the role of food are rarely addressed with respective frequencies of 6.3 %, 4.7 % and 3.9 %. These results also indicate that 9 West Africa countries published more than 84.2 % of the publications when 3.2 % were published by 2 countries from Central Africa and 12.6 % for 8 European countries. The analysis shows that more studies are needed to improve knowledge about techniques of the propagation of the species for silviculture and factors that influence the natural dissemination of the species in its natural habitat. &nbsp

Espèces Ligneuses de Savanes Sèches du Nord du Togo : Considérations Socioculturelles et Relations de Pouvoir des Parties Prenantes

Les espèces ligneuses du nord du Togo sont sujettes à de diverses utilisations pour satisfaire des besoins multiples des populations et leur gestion implique plusieurs acteurs. L’objectif de l’étude est d’apprécier les connaissances endogènes de ces espèces ligneuses, les préférences et les similarités. L’approche méthodologique est basée sur des enquêtes ethnobotaniques et socioéconomiques menées auprès de 14 groupes ethniques par interview individuel et par focus groups. Les analyses ont porté sur la Classification Ascendante Hiérarchique (CAH) des usages selon la méthode de Sorensen et sur la catégorisation des parties prenantes. Au sein des différents groupes socioculturels ciblés, il ressort un consensus, notamment sur les espèces utilisées pour une catégorie d’usage donnée. L’utilisation courante des espèces ligneuses est orientée simultanément sur deux grands types d’usages à savoir : (i) usages alimentaires, médicinaux, fourragères et rituels ; et (ii) usages artisanal, bois énergie et bois de service. Elle est rare pour un type spécifique d’usages cosmétiques ou hygiéniques. Ces usages sont similaires à quatre grands regroupements ethniques. Le résultat des inventaires réalisé sur l’ensemble des espèces ligneuses montrent que, 42 de ces espèces présentent une vulnérabilité forte. Les réalités socioculturelles et la promiscuité entre les groupes ethniques déterminent les connaissances et les choix de biens et services écosystémiques. Ainsi, il est recommandé que les programmes d’aménagements forestiers tiennent compte de ces facteurs y compris, les responsabilités locales de même que les influences et les intérêts des parties prenantes.   Woody species in northern Togo are used to meet multiple needs of populations and their management involves many actors. The study objective is to appreciate communities’ knowledge of these woody species, preferences, and similarities. The methodology is based on semi-directive ethnobotanical and socioeconomic surveys within 14 ethnic groups through individual interviews and focus groups discussions. The analysis included Hierarchical Upward Classification (HUC) of uses according to the Sorensen method, and on the characterization of the main stakeholders. Within the targeted various socio-cultural groups, there is a consensus, mainly on the species used for a given category of use. It emerges that woody species are frequently used for two goals (food and medicinal; livestock feeding and ritual), or three goals (artisanal, energy wood, and service wood) and rarely for a specific type of use (cosmetic or hygienic). Four main ethnic groups have similarities of uses and 42 out of all of the species identified, present a high vulnerability. Some local socio-cultural realities and promiscuity between ethnic groups determine the knowledge of forest trees and the choices of goods and services. Therefore, it is recommended for forest development programs to take into account the above factors including local responsibilities as well as influences and interests of stakeholders

IMPORTANCE SOCIO-ECONOMIQUE DE PTEROCARPUS ERINACEUS POIR. AU TOGO

Pterocarpus erinaceus Poir. (Fabaceae) is an spontaneous, highly exploited and threatened plant species to guineo-sudanese and sudanosahelian regions in Togo. This study examines the level of knowledge of the species, the different uses of the species in order to assess the impacts of human activities on the development of that resource. To achieve these objectives, the methodological approach was to collect quantitative and qualitative data on a sample of 2339 respondents. Three different types of questionnaires, an interview guide and an observation grid were used as data collection tools. The results show that the species is very well known by 100% of respondents of different socio-professional and socio-linguistic groups. Approximately 46 uses distributed in 8 use categories have been identified by the different socio-cultural and socio-professional groups. Close to 33 evils are healed by the organs of P. erinaceus.The results also showed that the wood of P. erinaceus is exported as finished parquet, pallets and Bastings. Between 2011 and 2012, the Togo exported respectively 18 8064 units or 70 m3, 10 5038 units or 9440 m3, 59 86 970 unit or 70 m3 and 239 m3 or 10 units of these products. Severe forms of exploitation have contributed to amplify the effects of human action on the degradation of the resource. The different uses of the species therefore testify to the urgency and the need for the implementation management plans of areas colonized by P. erinaceus for the conservation of the species

Challenges of Conservation and Sustainable Management of African Rosewood (<em>Pterocarpus</em><em>erinaceus</em>) in West Africa

Pterocarpus erinaceus is an endemic and threatened plant species in arid and semiarid zones of West Africa and is highly exploited for timber, animal feeding, and various medicinal uses. The species is currently native to the Guinean forest-savannah mosaic ecoregion and reported from Senegal to Cameroon. The values of the main characteristics of the P. erinaceus forest stands (density, average diameter, average height and average stem height) vary significantly (P < 10−3) from the Guinean zone to the Sahelian zone. It has high technological performance and can be classified as heavy and very hard wood with a density of the order of 0.80 ± 0.07 g/cm3 and an average hardness of 12 ± 3.7 g/cm3. The species is the subject of large-scale international traffic between West Africa and Asia, which is by far the greatest threat to the species. The various uses induce repeated mutilation and increase pressures on the species resulting in a significant reduction in its natural populations. In response to this situation, measures are proposed, including large-scale plant production strategies, the definition of minimum felling diameters, policy measures, etc., to meet the restoration needs of natural stands of P. erinaceus and the fight against climate change

Ecological drivers of pteridophyte diversity and distribution in Togo (West Africa)

International audienceThe conservation and sustainable management of biodiversity requires an understanding of the biotic and abiotic factors that condition the presence and survival of organisms in natural habitats. The global distribution and ecological hypersensitivity of pteridophytes have made them ideal candidates for studying the impact of biotic and abiotic factors on levels of biodiversity.This study aims to determine the effect of vegetation cover, human disturbance, and climatic factors on the distribution and diversity of pteridophytes in Togo with a view to guide conservation efforts. Our data comprises 130 plots of 500 m2 representing all ecological zones of the country, complemented by several opportunistic collections. After determining the patterns of pteridophyte distribution, multivariate analysis of variance and the calculation of diversity indicators made it possible to determine the influence of the factors studied.We found that pteridophyte species diversity and distribution in Togo are strongly influenced by climatic variables, with more than 90% of species diversity being concentrated in the submontane forest areas. Humidity related variables, insolation, and human disturbances are the main drivers of their distribution. Species diversity is positively associated with an increase in humidity, but decreases with increasing insolation and human disturbance. Importantly, our results emphasize the association of specific species to particular conditions created by climate, land cover, and human disturbances, highlighting the role of pteridophyte species as indicators of environmental conditions or exposure to stress. Within humid forest areas, our analysis of the impact of disturbance indicates that about a quarter of the pteridophyte flora of humid forests is sensitive to minor disturbances, whereas almost all rainforest species decline in the face of high levels of disturbance. Agroforests are a particular case of moderately disturbed rainforests, and have the potential to harbour at least 30.5% of Togolese rainforest pteridophyte species diversity.We conclude that the conservation of pteridophytes in Togo requires the protection of submontane rainforests and the adoption of less destructive practices in terrestrial species habitats in coffee/cocoa-based agroforests

Relations between the ecological conditions and the properties of Pterocarpus erinaceus Poir. wood from the Guinean-Sudanian and Sahelian zones of West Africa

Pterocarpus erinaceus (Poir) is currently the most exploited and threatened spontaneous tree species in the Guinean-Sudanian and Sudano-Sahelian zones in West Africa. This work analyzed the density and color parameters of P. erinaceus wood in the phytogeographic zones (Sudanian, Guinean and Sahelian) in three countries in West Africa (Togo, Burkina Faso and Niger). The results obtained by studying 451 specimens taken from 95 trees showed significant differences in basic density and color parameter values (P 0.05). This indicated that the age of the trees has little influence on the basic density of P. erinaceus wood

Isolation and characterization of microsatellite markers for the threatened African endemic tree species Pterocarpus erinaceus Poir.

To study the genetic diversity and structure of the forest species Pterocarpus erinaceus Poir., seventeen polymorphic nuclear microsatellite markers were isolated and characterized, using next-generation sequencing. Three hundred and sixty-five (365) individuals were analyzed within fifteen (15) West African populations. The number of alleles for these loci varied from 4 to 30, and the heterozygosity varied from 0.23 to 0.82. The seventeen (17) primers designed here will allow characterizing the genetic diversity of this threaten species on its natural stands and to better understand the population differentiation mechanisms shaping it