Article

Plant species and ecosystems with high conservation priority in Benin

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... However in Benin, most of these remaining forest patches, although playing the role of a high conservation priority area for heritage plants, are still experiencing severe threats due to the lack of adequate conservation strategies (Oloukoï et al. 2007;Adomou et al. 2010). This is probably the case with Ewe and Adakplame Relic Forest (EARF) in the south east of Benin. ...
... Unlike Palmer (1990) who showed that Jack 1 is the most precise and least biased, it is rather the Bootstrap estimator (200.52 ± 9.2808) that seems to be closer to our field results (S = 185 species). The Bootstrap value is also close to estimates of Adomou et al. (2010) who assessed the specific richness of EARF around 200 species. This is what justifies the calculation of the four estimation methods (Chao, first order jackknife, second order jackknife and bootstrap) and not only one as Palmer (1990) would have demonstrated. ...
... In our study, the species accumulation curves were calculated with estimators (Chao, Jack 1, Jack 2 and Bootstrap) and showed a change in species richness without flatten off at the right hand. The Bootstrap appears to be the best estimator which is closest to EARF plant richness estimated by Adomou et al. (2010). The Fig. 6 show that species accumulation curves were hardly tending towards the asymptote and are still climbing at the right hand end signifying that the sampling effort was insufficient. ...
Article
Full-text available
Covering 560.14 hectares in the south-east of Benin, the Ewe-Adakplame Relic Forest (EARF) is a micro-refugium that shows insular characteristics within the Dahomey Gap. It is probably one of the last remnants of tropical rain forest that would have survived the late Holocene dry period. Based on intensive field investigations through 25 plots (10 × 50 m size) and matching of herbarium specimens, a checklist of 185 species of vascular plant belonging to 54 families and 142 genera is presented for this forest. In addition to the name for each taxon, we described the life form following Raunkiaer’s definitions, chorology as well as threats to habitat. The Rubiaceae family was the richest (20 species) followed by the Fabaceae (15 species). Life forms showed the preponderance of phanerophytes (88%). The Chorological spectrum was dominated by Guineo-Congolean species (66%). Species richness estimated were 200.52 ± 9.2808 for Bootstrap ; 217.62 ± 14.5972; 224.16 ± 15.3725 and 242.67 respectively for Chao , Jacknife1 and Jacknife2 . Bootstrap appears to be the estimation closer to the field records. In Benin, EARF is home for Rinorea species described as West African forest bio-indicators and single location for Nesogordonia papaverifera , Mansonia altissima , Englerophytum oblanceolatum , Octolobus spectabilis , Vitex micrantha and most of Drypeteae tribe species ( Drypetes aframensis , Drypetes afzelii , Drypetes gilgiana and Drypetes leonensis ) recorded in Benin. Our results provides baseline information for further in-depth analysis of vegetation history in Benin by raising the question on the past floristic connection of the Dahomey gap and community engagement in conservation.
... At regional level, approximately 76% of all species are facing extinction risk due to loss and modification of their natural habitats (McNeely, 1996). In Benin, a total of 280 threatened plant species, representing 10% of the national flora, have been reported (Adomou et al., 2009). As the global strategy of plant conservation states that at least 60% of threatened plant species should be within protected areas (Vellak et al., 2009) there is increasing concern about the extent to which protected areas contribute to conserve threatened plant species and their habitat. ...
... e l s e v i e r . c o m / l o c a t e / e c o c o m previous international findings (Adomou et al., 2009; IUCN, 2008; Lykke, 1998; Hahn-Hadjali and Thiombiano, 2000). Adomou et al. (2009) reported that they are highly endangered in Benin. ...
... j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / e c o c o m previous international findings (Adomou et al., 2009; IUCN, 2008; Lykke, 1998; Hahn-Hadjali and Thiombiano, 2000). Adomou et al. (2009) reported that they are highly endangered in Benin. This is linked to their multiple uses such as medicine, fuel, craft and fodder (Eyog-Matig et al., 2002; Gautier et al., 2005; Oué draogoKoné et al., 2006) and also to land clearing for agriculture. The Pendjari Biosphere Reserve is a protected area located in the Sudanian zone and is t ...
... For example, Khaya senegalensis (Desv.) A. Juss, (Meliaceae) and Vitellaria paradoxa C.F. Gaertn (Sapotaceae) were reported to have anthelmintic properties that control gastrointestinal nematodes of ruminants (Ademola et al. 2004;Akouèdegni 2013), however, these species are also reported on the IUCN Red List (Ehinnou Koutchika et al. 2013). Similarly, populations of Pterocarpus erinaceus Poir., (Leguminosae-Papilionoideae), whose leaves and roots were shown to have antiparasitic effects on Haemonchus contorus, an abosomal nematode of small ruminants (Dédéhou et al. 2014), have declined over the last two decades (Adomou et al. 2009). Pterocarpus erinaceus is listed on the IUCN Red List of Threatened Species as 'endangered', while K. senegalensis and V. paradoxa are listed as 'vulnerable'. ...
... Pterocarpus erinaceus is listed on the IUCN Red List of Threatened Species as 'endangered', while K. senegalensis and V. paradoxa are listed as 'vulnerable'. Previous studies at a national level indicated that the above mentioned anthelmintic plants are highly threatened, as a result of overharvesting and other disturbances, such as bark and foliage harvesting, charcoal production, land clearing for itinerant agriculture, and overgrazed (Adomou et al. 2009;Gaoue and Ticktin 2008). As pointed out by Glèlè , the expansion of agriculture changed many of the forests into agroforestry systems, indicating a necessity to conserve tree diversity and socio-economically important tree species. ...
... Understanding plant species occurrence, distribution patterns and the underlying factors is a crucial step for the conservation and management of plant communities and ecosystems (Adomou et al. 2009). Furthermore, distribution patterns of threatened communities and plant species are used to improve on the existing protected area network and to guide plant diversity conservation. ...
Article
Full-text available
Smallholder farmers make intensive use of anthelmintic plant species in the traditional treatment of animal parasitic infections. As a result, populations of these plant species are exposed to increased disturbances such as plant harvesting, threatening their stability. Information on population structure of threatened plant species is important not only for understanding their ecological status but also for conservation and restoration purposes. Using floris-tic and structural data from 61 plots of 0.09 ha each, we assessed the population structures of the three anthelmin-tic species (Bridelia ferruginea, Mitragyna inermis, and Combretum glutinosum) along the climatic gradient (Guinean, Sudano-Guinean and Sudanian climatic zones) in Benin. Structural characteristics (tree density, basal area, mean diameter, tree height), and species-specific diameter and height distribution were assessed. Results showed that B. ferruginea was found in all three climatic zones, but more prominent in the Sudano-Guinean zone with a scarcity index of less than one per cent. Mitragyna inermis and C. glutinosum were only observed in the Guinean zone and Sudanian zone, respectively. Bridelia ferruginea population structures, especially density and basal area, varied significantly among climatic zones. Diameter-and height-class distributions for the three species exhibited a bell shape with a tendency to right skewness, indicating a predominance of younger trees. These results suggest that the three species are not currently threatened in Benin; however, it would be necessary to prevent overexploitation to guarantee future sustainability.
... In Benin, rainforest vegetation is restricted to about 1 000 sacred forests, most covering less than 1 ha. These southern forest remnants cover about 1% of the country, yet harbour 64% of critically threatened plant species (USDA 2007, Adomou et al. 2010, Adomou 2011) and numerous endangered animals -almost all outside established nature reserves . Most forests in southern Benin, but also those in adjoining south-western Nigeria, are located in highly populated areas (often >200 inhabitants/km 2 ) embedded in agricultural or peri-urban environments. ...
... Protection of the remaining rainforest in the Dahomey Gap and southwestern Nigeria is therefore urgent. In southern Benin, these are naturally small pockets, most of them sacred forests, which have been studied before (Sokpon and Akpo 1999, Nagel et al. 2004, Adomou et al. 2010, Agbani et al. 2012. The present study is, however, the first to relay the experience of the managers of such forests over a time span of 10 to 30 years, to describe rehabilitation of the forests and to take into account the threat-status of organisms (Table 2). ...
... . Endangered tree species include Afzelia africana VU, Afzelia bipindensis VU, Albizia ferruginea VU, Entandrophragma angolense VU, Entandrophragma cylindricum VU, Garcinia kola VU, Guarea cedrata VU, Khaya grandifoliola VU, Khaya senegalensis VU, Mansonia altissima EN, Nauclea diderichii VU, Nesogordonia papaverifera VU, Parkia bicolor EN, Strombosia pustulata EN, and Terminalia ivorensis VU.In addition to IUCN Red List species, local knowledge indicates that the following species are in steep decline: Alstonia boonei, Milicia excelsa, Pterocarpus erinaceus and Triplochiton scleroxylon.Table 1. List of scientific plant names, according to www.plantlist.com. Red List status for Benin seeAdomou et al. (2010) and for Nigeria see IUCN International List (VU = vulnerable, EN = endangered, CR = critically endangered, EW = extinct in the wild); + = not threatened, but mentioned in text for at least one forest. Status: July 2015.Barteria nigritiana Hook.f. ...
Article
Full-text available
The management schemes of four rain forest patches in southern Benin and southwestern Nigeria, which led to the successful protection of numerous threatened plants and animals over the last 20 plus years, are analysed. Since climatic conditions are similar, tree composition depends largely on different availability of water and documented biodiversity mostly on the availability of taxonomic expertise. Management differs according to accessibility and human population pressure, from total closing off of the forest by an international institute near the mega-polis Ibadan to unmarked borders near Lanzron, a remote village in the lower Ouémé Valley, where foreigners are mostly excluded from visiting the site. In Benin, trees and wildlife (antelopes and monkeys) seem best protected where the local vodoun beliefs are adhered to. This is, however, not sufficient and development aid to support and benefit the local population is needed as exemplified in Zinvié. At the Ibadan and Drabo sites, long-term protection is assured by legally-binding land-titles. Since for all of Lanzron and part of Zinvié these are lacking securing them is a priority. In Ibadan, Nigeria, a major rehabilitation effort is concentrated on bringing relatively old grass land and former village sites under forest cover by planting local trees. Rehabilitation in Drabo, in southern Benin, relies on enriching the naturally occurring fallow succession with rare species from nearby threatened sacred forests. We demonstrate that reversing biodiversity loss is possible but requires a long-term commitment. Recommendations for protecting, stabilizing and enhancing similar small hotspots of biodiversity are made.
... Because of these uses,A. africana is classified as endangered at country-scale (Adomou et al. 2009).The acknowledged utility of the species in tandem with its insistent harvesting has increased the investigations at local and regional scales (Sinsin et al. 2004, Bonou et al. 2009, Ouédraogo and Thiombiano 2012, Houehanou et al. 2013a). ...
... Moreover, the highest density of regeneration was observed in this climatic zone. Thus, the species is supposed to be more adapted to the climatic conditions of the Guinean zone (Houehanou et al. 2013b) even though it has been reported as being mostly valued in the Sudanian regions (Adomou et al. 2009, Nacoulma et al. 2011. In fact, Sudanian and Sudano-Guinean zones are still the potential areas for the seasonal movements of herds. ...
... ). Among these species, A. africana is the most threatened species and is classified as endangered at country-scale (Adomou et al., 2009). There are regional scale studies (Sinsin et al., 2004;Bonou et al., 2009;Houehanou et al., 2013;Ouédraogo and Thiombiano, 2012) that elucidated the current traits of A. africana populations and reported a very weak potential of recruitment. ...
... Moreover, the highest density of regeneration was observed in this climatic zone. Thus, the species is supposed to be more adapted to the climatic conditions of the Guinean zone (Houehanou et al., 2013) even though it has been reported as being mostly valued in the Sudanian regions (Adomou et al., 2009;Nacoulma et al., 2011). In fact, Sudanian and Sudano-Guinean zones are still the potential areas for the seasonal movements of herds. ...
Article
Full-text available
Anthropogenic disturbances and climatic variations are presumed to alter species population structures. In this study,we assessed the population structure of the endangered species, Afzelia africana across gradients of climate and human disturbances. Dendrometric variables such as regeneration and tree density, mean diameter, basal area and height and stem diameter distribution were recorded at national scale in forest reserves located in three different climatic zones in Bénin. A canonical discriminant analysiswas applied to describe the species' population structure across climatic zones and disturbance levels. Relationships between the principal components (structural parameters of A. africana stands) and climatic variables and disturbance levels were assessed using Pearson correlation. Significant differences were found in the structural parameters between the disturbance levels, mostly in the Guinean zone. Structural parameters also differed significantly across the three climatic zones, with the Guinean zone recording the highest values. The effects of disturbance levels on structural parameters depend on the climatic zone, and vice versa. The results imply an interaction between climatic zones and disturbance levels. In the Guinean zone, the tallest and biggest trees were found at the low disturbance level. However, along the climatic gradient (towards drier regions), trees were shorter and smaller irrespective of disturbance level. Further, the tallest and biggest trees were found at lower altitudes.
... Family names follow taxonomic revisions (APG I 1998, for least differences with Akoègninou et al. 2006). -Chorology according to Adomou et al. (2010 and Akoègninou et al. (2006): The origin of the species is indicated as follows ( Figure 1): GC Guineo-Congo forest species that are distributed across the Upper and Lower Guinean and into the Congolese zone east to Sudan, Uganda, Kenya, GO Upper Guinea forest species from west of the Dahomey Gap with an eastern limit in Benin or nearby Nigeria, GE Lower Guinea forest species from east of the Dahomey Gap with a western limit in Benin, SG Guineo-Sudanian transition zone species, SZ Sudanian savannah species, and S Sahel savannah species. Many species occur in different zones; only their main habitat is indicated. ...
Article
Full-text available
In a twenty-year effort at Drabo, southern Benin, small remnant forests, young fallow and agricultural fields were linked and rehabilitated to develop a 14 ha forest reserve. Forest regrowth was encouraged by managing the natural growth of the local fallow vegetation and by bringing in seeds and other propagules from forest islands of Benin. The succession to shade-tolerant woody forest species of Guineo-Congolian origin at the expense of extra-regional herbs, the co-existence of species with slightly different requirements, and the fate of exotic trees in this natural forest are described. A quantitative assessment of a homogeneous lot indicated 397 trees per ha, with stem diameters >10 cm, 43.7% of them below 20 cm, and a rich undergrowth of 72600 smaller plants per ha, proof of active rejuvenation. Only 4.2% of all plants resulted from the 1041 introduction events, i.e., species per date, mostly of the 253 plant species that were new to Drabo. A total of 635 species were recorded, but 50 did not survive and four are yet to be identified. In June 2016, the total of 581 known living species included 224 trees. Among all plants, 244 hailed from the Guineo-Congolian zone with 17 of Upper Guinean and four of Lower Guinean origin, 113 from the three savannah zones, and 224 were of extra-regional origin. Overall, 72.8% of all woody plants, such as many climbers, all shrubs and trees, were of forest and savanna origin (GC, SG, SZ and S), whereas 70.4% of all herbs came from other regions (At, PAL and Pt). Only 7.0% of all species from the GC zone were in decline; but the further away the plants originated from, the larger the decline in numbers and vigour, up to 64.6% among plants of pan-tropical origin. Particularly pan-tropical herbs became ever rarer, with 80.0% of them declining and confined to the few open spaces along paths. In 2017 the forest harboured 52 threatened species, with threat categories EW, CR, EN or VU on the Red List of Benin, out of 73 IUCN-listed species that could possibly survive in Drabo. Some of these species occur in only one or two other locations in Benin. The biodiversity richness of the rehabilitated forests of Drabo now rivals that of natural rainforest remnants of the region. As the surrounding landscape becomes ever more impoverished because of the high human population and its ever increasing impact, the maintenance of such managed islands of biodiversity is critical. By establishing rare local species from other locations we can compensate for direct human destruction and long-term stochastic loss of species in this highly fragmented landscape where natural seed dispersal is difficult. Benin, sacred forest, threatened plants, IUCN Red List, forest regeneration, Guineo-Congolese semi-deciduous forest
... These three species are used as medicine, fuel and fodder (Eyog-Matig et al., 2002;Gautier et al., 2005;Ouédraogo-Koné et al., 2006). These uses are expressing high pressure on their populations, which in turn are declining throughout West Africa (Adomou et al., 2009;Lykke, 1998;Hahn-Hadjali and Thiombiano, 2000). As a consequence, these species should have priority for biodiversity conservation. ...
... ces de prélèvement ; – la préférence des espèces et critères utilisés à cet effet ; – les raisons de choix des ligneux pâturés ; – le moment de l'année où l'on a recours au fourrage ligneux ; – les espèces devenant de plus en plus rares et raisons de raréfaction ; – les catégories d'animaux (ovins, caprins, bovins) nourris avec le fourrage ligneux.Adomou et al., 2010 ; Sinsin et al., 2010). ...
Article
Full-text available
Diversity, pastoral and conservation priorities of fodder trees in the Sudano-Guinean pasture lands of Benin. Description of the subject. Fodder trees are important for livestock survival in dryland Africa. In view of the pressure faced by these trees, and their consequent rarity noted in rangelands, a study was conducted in the Sudano-Guinean transition zone of Benin at the level of the local population surrounding the protected forests of Monts Kouffé, Wari-Maro and Ouémé Supérieur. Objectives. This study aimed to inventory the fodder trees, analyze the local perception of factors threatening target fodder trees, according to different sociolinguistic groups and prioritize fodder trees for conservation. Method. Ethnobiological surveys and ecological data from the available literature were used to construct a database following different criteria. The citation rates of the fodder trees by the surveyed populations were used to establish pastoral priority, while their conservation priority was established using a combination of four methods and nine criteria. Results. Forty-eight fodder trees belonging to 17 families dominated by Leguminosae (27.1%) and Moraceae (16.6%) were reported. These species were distributed among 37 genera, with the genus Ficus being the most represented (16.6%). Palatability, species availability and the impact of tree fodder on animal productivity were the criteria used by the surveyed sociolinguistic groups in their selection of fodder trees. The prioritization methods yielded ten top ranked species: Afzelia africana, Pterocarpus erinaceus, Khaya senegalensis, Vitellaria paradoxa, Mangifera indica, Ficus platyphylla, Balanites aegyptiaca, Annona senegalensis, Ficus umbellata and Daniellia oliveri. Conclusions. With the aim of establishing the sustainable management of pasture lands, we suggest that priority be given to the aforementioned species of fodder trees as part of restoration, afforestation/reforestation and plantation activities.
... and A. leiocarpa. Moreover, most of these species, mainly P. erinaceus, A. africana and K. senegalensis are considered as plant species with high conservation priority in Benin (Adomou et al., 2010) and endangered on the red list of plant threatened species of Benin (Neuenschwander et al., 2011). Thus, a continued illegal logging of these species may implies severe threats to their populations. ...
Article
Full-text available
This study assessed ecological consequences of anthropogenic pressure on Wari-Maro Forest Reserve (WMFR). The dynamics of forest cover has been assessed using a diachronic analysis of land cover maps from the Landsat satellite images of 1986, 1995 and 2006. Structural patterns of the forest has been described using forest inventory data with twenty five 1ha plots having two 50 m x 30 m plots set up inside and positioned at the opposite corners of the leading diagonal within each 1 ha plot. Established plots allowed identifying the most targeted species in illegal logging. Plots of 0.15 ha established inside each 1 ha plot helped assessing the volume of trees from which we derived carbon stock and carbon loss using conversion and expansion factors. For the two periods 1986 to 1995 and 1995 to 2006, there was a decline in forest cover which slowed down in the second decade (0.196 %.year-1 and 0.083 %.year-1 respectively). The two vegetation types of the WMFR were mainly distinguished by Lorey's mean height (12.81 m in woodland and 12.44 m in tree-savannah). Top five targeted species in illegal logging activities were: Pterocarpus erinaceus Poir., Afzelia africana Sm., Isoberlinia spp., Anogeissus leiocarpa Guill. and Daniellia oliveri (Rolfe) Hutch. & Dalziel. Results also showed mean values of carbon stock and carbon losses for the whole forest of 147.84 tons C.ha-1 and 17.57 tons C.ha-1 respectively and did not depend on vegetation type. Results from this study suggest that management strategies should focus on selectively logged species. Monitoring should also be enhanced to ensure conservation of resources of the reserve which are at high risks of extinction due to selective logging rates. Keywords: anthropogenic pressure, forest cover, structure, carbon stock, Wari-Maro forest reserve, Benin.
... Trees have a multifunctional role and wood from Studies conducted in Benin, following the criteria of the them is a highly valued material. In the implementation of International Union for Conservation of Nature (IUCN), projects for the construction of tourist structures on have classified Mimusops andongensis Hiern as a rare stilts, wood species with high technological and threatened species in Benin [5][6][7][8]. The rarity of this characteristics are sought. ...
Article
Full-text available
Wood is a multifunctional anisotropic biomaterial. It is used in various fields, including the craft industry and the construction of structural works. In heavy construction or in wetlands, species with high technological characteristics are sought after. Mimusops andongensis is a species empirically identified as having good technological properties. However, none of these reference characteristics are known. Thus, to fill this gap, we tested 500 mm × 20 mm × 20 mm prismatic specimens of Mimusops andongensis wood using CIRAD-Forest's acoustic BING (Beam Identification by Non-destructive Grading) method to determine density , Young's modulus E and shear modulus G, internal friction tan and then evaluated the specific stiffness modulus E/. On other 20 mm side cubic specimens, we evaluated the physical properties. From this investigation, Mimusops andongensis timber is a heavy to very heavy timber with high modulus. Its volume shrinkage is moderate with low tangential and medium radial shrinkage. Its low shrinkage anisotropy predicts low distortional and splitting deformation. Its specific stiffness is high on the order of (18 ± 1) GPa for a low internal friction of (0.64 ± 0.15) × 10. In a humid environment, the loss of mechanical properties, by increasing 2 its moisture content, even by 20 %, leaves Mimusops andongensis timber in the range of woods with very appreciable properties. Referring to the highly valued species, it can be used in works both in structure and acoustics.
... One of the direct consequences of international trade and local exploitation of the species organs is the severe decline of its populations. Hence, at the international level, populations of P. erinaceus are declining due to human pressure (Adomou, Sinsin, Akoegninou, & van der Maesen, 2009;Houehanou et al., 2013;IUCN, 2008;Lykke, 1998;Nacoulma et al., 2011). In West Africa, P. erinaceus populations are studied across climatic zones (Sègla et al., 2015(Sègla et al., , 2016 and in some natural forests (Glèlè Kakaï, Sinsin, & Palm, 2008;Glèlè Kakaï, Assogbadjo, Sinsin, & Pelz, 2009). ...
Article
Human‐modified systems come as innovative ones necessary to be more understood to attain biodiversity conservation goals. This study aimed to assess the effect of human disturbance on the population structure of Pterocarpus erinaceus in different land use types (Highly protected area, Moderately protected area and Non‐protected area) in Sudanian savannahs of Togo. Data were collected in forty randomly set plots (50 m × 30 m) within each land use type. Population structure parameters and leaf and leaflet morphological traits were evaluated and compared among the land use types by performing different statistical analyses. Results showed an adverse effect of human disturbance on adult and juveniles densities as well as the total height (significant difference between highly protected and non‐protected areas; p < 0.001). Diameter class structures revealed in the three land use types an inverted J‐shape indicating the predominance of young individuals. Significantly greater (p < 0.001) values of leaflet length were observed in the non‐protected area compared to highly protected one. The human‐mediated area impacted the diameter‐height relation and the one among assessed leaf and leaflet traits. These findings are tools to be incorporated in new policy development for the future management of this tree species population. Résumé Les systèmes modifiés par les hommes sont des systèmes nouveaux qu'il faut mieux comprendre afin d'atteindre les objectifs de conservation de la biodiversité. Cette étude visait à évaluer l'effet de perturbations humaines sur la structure de populations de Pterocarpus erinaceus dans différents types d'utilisation des (zone très protégée, moyennement protégée et non protégée) dans des savanes soudaniennes du Togo. Des données furent récoltées dans des 40 parcelles de 50 m x 30 m installées de façon aléatoire dans chaque type d'utilisation des terres Les paramètres de la structure des populations et les caractéristiques morphologiques des feuilles et folioles ont été évalués et comparés selon les types d'utilisation des terres en faisant différentes analyses statistiques.Les résultats ont montré un effet négatif des perturbations humaines sur la densité des jeunes et des adultes ainsi que sur la hauteur totale (différence significative entre parcelle très protégée et non protégée : P<0,001). La structure des classes de diamètre a révélé dans les trois types d'utilisation des terres une forme en J renversé qui indique la prédominance de jeunes individus. Des valeurs significativement plus grandes (P<0,001) de la longueur des folioles ont été observées dans la zone non protégée que dans la zone très protégée. La zone impactée par les hommes influence la relation diamètre‐hauteur et celle entre les caractéristiques évaluées des feuilles petites et grandes. Ces résultats sont de nouveaux outils qu'il faut intégrer dans les nouvelles politiques de développpement pour la gestion future des populations de cette espèce d'arbre.
... Afzelia africana Sm. (Fabaceae, APG III) is among the most vulnerable tree species in West Africa because of its high exploitation by local communities due to its value in medicine or as fodder (Houehanou et al. 2011), and especially because of its significant economic role for timber manufacturers. Consequently, a severe decline of this tree species has already been reported in many places at local as well as regional level (Hahn-Hadjali and Thiombiano 2000;IUCN 2008;Adomou et al. 2009, Houehanou et al. 2013. Sustainable management and conservation of that tree species became necessary and thus, knowledge of how climatic condition and human disturbance can shift its morphological traits will help to design the related strategies. ...
Article
Full-text available
Afzelia africana Sm. is a tree species found in different climatic conditions affected by chronic human disturbance. It is known that trees can respond to their environments by changing their morphological traits. Also, as plants store their reserves in fruits, seeds and leaves, long-lasting disturbance may impact morphological traits of fruits, seeds and leaves. Thus, in this study, we evaluated (1) the variation of morphological traits of A. africana according to climatic conditions and human disturbance, and (2) the relationships among morphological traits. Twelve morphological parameters based on fruits, seeds and leaflets were assessed across three climatic zones and compared for individuals in protected and disturbed landscapes. Univariate and multivariate analyses were used to evaluate the effects of climatic factors and disturbance. Highest values for fruit, seed and leaflet traits were observed in humid areas indicating for best performance under optimal conditions. Significant adverse effects of human disturbance were observed for traits in the humid and drier areas. The interaction between climatic conditions and disturbance was significant for most traits suggesting a climate-dependent effect of the disturbance on evaluated traits. Bioclimatic variables were thus identified as potential drivers of traits. Some significant and positive associations were observed among fruit and seed traits. These morphological trait variations are valuable insights to guide sustainable management and conservation of A. africana populations in different climatic zones and habitats types in Benin.
... In Benin, M. excelsa is commercially known as "Iroko" and is a sacred species, especially within the villages. It is of economic importance adapted to tropical environments but critically endangered in Benin (Adomou et al. 2010). This study estimates current and future suitable areas for M. excelsa and assesses conservation gaps of the species for better conservation in Benin. ...
Article
Full-text available
African teak (Milicia excelsa (Welw.) C.C. Berg) is an endangered multi-use species. Understanding the impact of climate change on the distribution of this species may improve the ability to anticipate or recognize its decline or expansion and to take appropriate conservation measures if necessary. Ecological niche modeling was projected in geographical space to study the current and future distribution of M. excelsa in Bénin. MaxEnt was used to estimate the potential geographic distribution of the species under two Representative Concentration Pathways (RCP). Miroc 5 summaries and two RCP 4.5 and RCP 8.5 scenarios were used as predictor variables for projections of the geographic potential of this species. The performance of the model was assessed by the area under the curve (AUC), true skill statistics (TSS) and partial receiver operating characteristics (Partial ROC). From the results, M. excelsa was more a secondary species in the Guinean climatic zone and part of the Sudanian-Guinean and Sudanian climatic zone. The projections show a significant decrease in suitable habitats for the species from the two RCP scenarios. Only a part of the Guinean climatic zone remained suitable and few protected areas will conserve in situ M. excelsa. For the sustainable conservation of M. excelsa, it is essential to strengthen the protection of sacred forests located in the Guinean climatic zone.
... Except for timber, the species of Afzelia as legumes are valued in the agro-forestry for their nitrogen fixation ability which enriches the soil. However, the natural populations are threatened by habitat loss as well as overexploitation because harvesting has greatly exceeded the regeneration rate of these trees (Adomou et al. 2010). Therefore, the conservation status of the Afzelia species needs critical investigation in most countries. ...
Article
• Key message Distinct chemical fingerprints of the wood of Afzelia pachyloba and A. bipindensis demonstrated an effective method for identifying these two commercially important species. Direct analysis in real-time (DART) time-of-flight mass spectrometry (TOFMS) allowed high-throughput examination of chemotypes with vast potential in taxonomic, ecological, and forensic research of wood. • Context Afzelia is a genus of valuable tropical timber trees. Accurate identification of wood is required for the prevention of illicit timber trade as well as for certification purposes in the forest and wood products industry. For many years, particular interest has been focused on attempts to distinguish the wood of A. bipindensis Harms from A. pachyloba Harms due to substantial differences in the commercial values of these two species.• Aims We investigated if wood chemical signatures and microscopy could identify the wood of A. bipindensis and A. pachyloba.• Methods We used two approaches, namely metabolome profiling by direct analysis in real-time (DART) time-of-flight mass spectrometry (TOFMS) and wood microstructure by light microscopy and SEM. In all, we analyzed samples from 89 trees of A. bipindensis, and A. pachyloba.• Results The two species could not be separated by the IAWA standard microscopic wood features. SEM analysis showed considerable variation in the morphology of vestured pits; however, this variation was not species-specific. In contrast, DART-TOFMS followed by unsupervised statistics (Discriminant Analysis of Principal Components) showed distinct metabolome signatures of the two species.• Conclusion DART-TOFMS provides a rapid method for wood identification that can be easily applied to small heartwood samples. Time- and cost-effective classification of wood chemotypes by DART-TOFMS can have potential applications in various research questions in forestry, wood science, tree-ecophysiology, and forensics.
... These three species are used as medicine, fuel and fodder (Eyog-Matig et al., 2002;Gautier et al., 2005;Ouédraogo-Koné et al., 2006). These uses are expressing high pressure on their populations, which in turn are declining throughout West Africa (Adomou et al., 2009;Lykke, 1998;Hahn-Hadjali and Thiombiano, 2000). As a consequence, these species should have priority for biodiversity conservation. ...
Article
Full-text available
Diverses essences forestières, dont cer-taines sont menacées, sont exploitées pour leur bois, légalement ou non. Les essences prioritaires pour la conservation à long terme doivent donc être défi-nies. La présente étude a permis de réali-ser un inventaire des essences exploitées au Bénin et d'identifier les essences prioritaires pour lesquelles des actions urgentes de conservation et de restau-ration sont nécessaires. Des recherches bibliographiques complétées par des entretiens avec différentes parties pre-nantes ont été menées afin de recueillir les données requises pour dresser une liste exhaustive des essences priori-taires. Dix critères et quatre méthodes de priorisation ont été utilisés. Au final, l'approche a retenu 10 essences parmi les 15 essences prioritaires définies par chacune des méthodes. Au total, 24 espèces végétales ont été identifiées, appartenant à 9 familles : Fabacées (25 %), Malvacées (20,83 %), Mélia-cées (16,67 %), Combrétacées (8,33 %), Moracées (8,33 %), Verbénacées (8,33 %), Ébénacées (4,17 %), Rutacées (4,17 %) et Myrtacées (4,17 %). Des mesures de conservation et de restaura-tion sont préconisées d'urgence pour les 10 essences prioritaires ainsi retenues.
Article
The study of anthropogenic impacts on tropical forests is vital in the design and development of sustainable extraction systems for both timber and non-timber products. However, distinguishing non-timber forest products (NTFPs) harvesting impacts from timber extraction consequences on the vegetation could be difficult, since tropical forest species often have a multipurpose status. This study explores the purposes and characteristics of timber and non-timber products usage in the Swamp Forest of Lokoli (in the south of Benin Republic) and assesses extraction impacts on the forest dynamics. We used structural parameters analysis and ecological indices to explain the vegetation structure and the species responses to anthropogenic pressures. The results suggest that the forest is being devastated by extraction activities of the local people including both timber collection and non-timber harvesting. Finally, this paper suggests that management policies balancing socio-economic and conservation priorities, through introduction of alternative economic activities, strengthening of the local agriculture and a participatory management plan are the best options for the long term preservation of this forest.
Article
Wild oil plants (WOP) are species used for food, cosmetics, nutraceutical, and medicine. In Benin, their importance is still poorly documented. This study investigated the diversity of WOPs and identified priority species for valorization in Benin. Literature synthesis was used to gather data on a list of WOP species. This was completed by ethnobotanical surveys involving users (traditional healers, farmers, fishers, traders, and resource persons), actors in the three biogeographical zones of Benin (Guineo-Congolian, Sudano-Guinean, and Sudanian zones). In addition, field visits to the species habitats were conducted with the help of local populations to assess the true presence of species mentioned during the survey and their availability. Data were collected on the identity of informants, WOPs used or known, ethnobotanical, nutritional and economic values, valorization level, their national distribution and threat status. Data were analyzed using the Chi-square test and Principal Component Analysis (PCA). Findings showed that oils extracted from these WOP seeds serve for medicinal (49.25%), food (29.85%), cosmetic (17.91%), and fuel (2.99%) purposes, and neither gender nor the main occupation defined knowledge of WOP diversity. A total of 36 WOPs belonging to 25 botanical families were identified. The top five priority species to be valorized across the country were: Balanites aegyptiaca (L.) Delile, Ricinodendron heudelotii (Bail.) Pierre, Lophira lanceolata Tiegh. ex Keay, Sesamum indicum L., and Cleome gynandra L. These species were identified as important resources for alleviating poverty and food insecurity in the communities and as potential candidates for the development of the oilseed sector in Benin. Further studies are needed to document the indigenous knowledge associated with those species, existing processing techniques, and exploitable capital to ensure their sustainable management.
Article
Full-text available
Fighting against invasive species is a great challenge that requires knowledge about their potential distribution areas. Ageratum conyzoides is an invasive species in several African countries including Benin. In order to analyze the vulnerability of protected areas of Benin to the invasion of this species, and to guide managers of these areas to fight against invasions, this study used MaxEnt to model the ecological niche of the species under the current and future climates, horizon 2055 RCP 4.5 and RCP 8.5 scenarios. Environmental data and presence data were gathered respectively from the data bases of AfriClim and GBIF. From the current to the future climates, the potentially suitable areas for the distribution of the species shift from the center to the south of Benin. So, about 75%, 51% and 65% of Benin’s total area are respectively suitable under present climate, and future’s ones (RCP4.5 and RCP8.5). Only about 16% and 43% of this area are absolutely unsuitable and absolutely suitable to the species. As for protected areas, about 29% and 25% of their total area are respectively not vulnerable, and vulnerable to Ageratum conyzoides. Present climate, and future’s ones (RCP4.5, and RCP8.5) held respectively about 62%, 28%, and 48% of protected areas total superficies vulnerable to Ageratum conyzoides.
Article
La commercialisation et l’utilisation des essences médicinales constituent des pratiques très courantes en Afrique et en particulier au Bénin. Une enquête a été effectuée chez une seule vendeuse disposant de trois différents étalages. L’inventaire minutieux et détaillé des trois étals a duré 30 jours. Un total de 205 espèces végétales groupées en 181 genres et 74 familles ont été recensées. Les familles les plus représentées en termes de richesse spécifique sont : Leguminosae (15%), Rubiaceae (7%) et Euphorbiaceae (7%). Ces espèces sont utilisées dans la formulation de 41 recettes pour traiter 37 maladies et symptômes. Le spectre biologique montre une nette prédominance des phanérophytes (68%). L’analyse biogéographique montre une dominance des espèces guinéo-congolaises (29%), pantropicales (29%) et afrotropicales (10%). Les tiges feuillées (67%) et racines (15%) constituent les organes les plus prisés. La décoction (86%) et le savon (12%) sont les formes pharmaceutiques fréquemment enregistrées. Les maladies et symptômes les plus fréquemment cités par les acheteurs sont: paludisme, diarrhée, stérilité, troubles menstruels, ictère, infections. Au nombre des plantes les plus vendues et rares, on peut citer: Khaya senegalensis, Monodora myristica, Xylopia aethiopica, Tetrapleura tetraptera, Acridocarpus smeathmannii et Entada gigas. La vente des plantes médicinales constitue non seulement une activité génératrice de revenu, mais contribue aussi aux soins de santé primaire, à la vulgarisation et la pérennisation du savoir endogène associé à l’utilisation des plantes médicinales.Mots clés: Plantes médicinales commercialisées, diversité, utilisations, rareté, Bénin
Thesis
Full-text available
Native plant species in general and fodder trees in particular contribute significantly to the daily needs of both human and animal especially in developing countries. During the dry season, fodder trees are an important source for the survival of ruminants because of herbaceous forage lack. They are multipurpose species exploited by various actors who are sometimes protagonists. In view of the pressure faced by these trees, and their consequent rarity noted in rangelands, a study was conducted in the Guineo-Congolese/Sudanian transition zone of Benin at the level of the local population surrounding the protected forests of Monts Kouffé, Wari-Maro and Ouémé Supérieur. This thesis contributes to the rational management of fodder trees’ resources. Specifically, it aims at (i) evaluate the diversity, the pastoral and conservation priority of fodder trees; (ii) assess the influence of age, sex and ethnicity on the perception of fodder species use values; (iii) describe the relationship between the availability and the use status of fodder species; (iv) develop models for estimating leaf biomass of three priority browse species; (v) contribute to the understanding of the socio-cultural dynamics of the study area in relation to the fodder trees’ exploitation and the associated conflicts. A total of 220 informants belonging to three sociolinguistic groups (Bariba, Nago and Peul) were interviewed through a semi-structured survey on the fodder trees that they use for different purposes. The citation rates of the fodder trees by the surveyed populations were used to establish pastoral priority, while their conservation priority was established using a combination of four methods and nine criteria. The use categories were defined in the study area and at an international level for the use rates calculation. The ethnoecological approaches were used to analyze the availability of fodder tree species in the study region. A total of 25 trees per species were sampled for biomass estimating. Carrying capacity was determined for the dry season in the study area. A total of 48 fodder trees belonging to 17 families dominated by Leguminosae (27.1%) and Moraceae (16.6%) were reported. These species were distributed among 37 genera, with the genus Ficus being the most represented (16.6%). Palatability, species availability and the impact of tree fodder on animal productivity were the criteria used by the surveyed sociolinguistic groups in their selection of fodder trees. The prioritization methods yielded ten top ranked species: Afzelia africana, Pterocarpus erinaceus, Khaya senegalensis, Vitellaria paradoxa, Mangifera indica, Ficus platyphylla, Balanites aegyptiaca, Annona senegalensis, Ficus umbellata and Daniellia oliveri. As a multipurpose species, the fodder trees are classified in six use categories: food, medicine, construction, fuel, veterinary and fodder. A. africana, K. senegalensis and P. erinaceus are the most widely used species by Peul and Bariba sociolingustic groups to feed animals, while the Nagos use M. indica comes first followed by F. umbellata, F. platyphylla and P. Erinaceus. Combining the different use categories, overharvested or underutilized species depend significantly on the sociolinguistic group. The forest inventory revealed 63 tree species of dbh ≥ 10 cm distributed in 24 families and 52 genera. The most represented families in genus and species are Leguminosae (28.57 %), Combretaceae (14.28 %). The Leguminosae family had the highest importance values (FIVI=83.42) followed at a distance by Combretaceae (21.68). The most important and ecologically dominant species are V paradoxa (SIVI = 42.76); I. doka (41,88); B. ferruginea (22.98); and D. oliveri (16,18). It is also noted that aerial fodder production significantly varied among species. The best models that estimated leaf biomass production of A. africana and P. erinaceus were obtained with diameter at breast height; a plant trait not directly affected by pruning as predictors. For D. oliveri the best model uses the crown height as estimator parameter. Globally, the carrying capacity of each species is about 0.05 to 0.09 TLU ha-1an-1 for A. africana; 0.03 to 0.08 TLU ha-1an-1 for P. erinaceus and 0.04 to 0.79 TLU ha-1an-1 for D. oliveri. The number of animal that can sustainably be fed in the study area was 38 497 TLU. Conflicts arise between sawyers and foresters, between foresters and Peul (herders), farmers and herders, farmers and sawyers, foresters and farmers. These conflicts are caused by the illegal exploitation of trees for their timber and fodder, and the breeders camp near the agricultural areas or sometimes in the forest reserves. Direct negotiations between those involved in conflicts or the arbitration of a local authority were the main strategies and ways of these conflicts managing. With the aim of establishing a sustainable management of pasture lands, we suggest that priority be given to the pastoral and conservation priority species witch are also overexploited species in the restoration, afforestation/reforestation and plantation activities. The introduction of these fodder tree species in afforestation/reforestation activities can improve the availability of leaf biomass to feed animals. Keywords: Availability, Benin, Biodiversity, Conservation priority, Ethnoecology, Fodder trees, Leaf biomass, Pastoralism.
Article
Full-text available
This study assessed endogenous knowledge and impact of human disturbance on the abundance of two underutilized wild fruit tree species: Drypetes floribunda (Mu¨ll. Arg.) Hutch. (Euphorbiaceae) and Mimusops andongensis Hiern. (Sapotaceae) in the Lama Forest Reserve (LFR) in southern Benin. A survey was conducted with 145 randomly selected people amongst the surrounding communities of LFR in order to assess the endogenous knowledge of the species. One hundred square plots were established in the forest for characterizing species abundance in different habitats according to human disturbance degree. Results indicated that this species has multiple uses and either local knowledge on their uses or their organ plant uses depend on social factors. A densities assessment suggests a negative effect of human disturbance on the abundance of both species. Results support the need to envisage conservation and sustainable use strategies as perspective policies.
Article
Full-text available
A floristic and dendrometric analysis was carried out using 15 square plots of 1 ha each in the Belléfoungou forest reserve, located in the Sudano-Guinean zone of Benin. Species and diameter at breast height of trees were recorded. Multidimensional scaling and importance value index of species were used to identify vegetation types in the reserve: (1) Isoberlinia tomentosa-dominated vegetation type, (2) Isoberlinia doka and Burkea africana-dominated vegetation type and (3) Vitellaria paradoxa and Isoberlinia doka-dominated vegetation type. Significant differences were noted between the three vegetation types with respect to the basal area of trees. This varied from 8.55 m2/ha (vegetation type 3) to 13.36 m2/ha (vegetation type 2). The overall woody species richness was 57 species. The stem diameter structures of all three vegetation types showed an inverse “J” shape, suggesting that the study reserve has stable natural vegetation with relatively more young stems than large stems. Setting and implementation of a sustainable management plan, and supervision reinforcement were suggested to enable conservation of the Belléfoungou forest reserve.
Article
Full-text available
Despite growing literature supporting the importance of home gardens (HG) as biodiversity hotspots, knowledge of patterns of their contribution to conservation of threatened species and crop wild relatives (CWR) across climate and culture in Africa is still limited. This investigation was conducted across three climatic zones to assess the floristic diversity of home gardens and the extent to which they contribute to conservation of threatened species and CWR. Overall, 240 home gardens were sampled and their floristic diversity assessed. The ecological importance of recorded species was determined per climatic zone using the importance value index (IVI). A cluster analysis was performed to group the species according to their IVI-values and a principal component analysis helped to identify the most important species. species were inventoried throughout the study area. Home garden species’ diversity globally declined from the drier to the wetter zone but was highest in the transition zone. The average number of species found per HG was 10.1 and varied weakly across zones (9.07, Guineo-Congolean zone; 10.77, Sudano-Guinean zone; and 10.53, Sudanian zone). The most important home gardens species in the Sudanian, the Sudano-Guinean and the Guineo-Congolean zones were respectively: Abelmoschus esculentus (L.) Moench and Hibiscus asper Hook f.; Solanum lycopersicum Mill and Zea mays L.; Ipomoea aquatica (L.) Ker-Gawl and Senna occidentalis (L.) Link. They were mainly vegetables and used as food and/or medicinal plant species. Twenty CWR and twelve threatened species were recorded and were also mainly used for food and medicinal purposes. Thorough research on socioeconomic factors supporting possession of HG and choice of managed species as well as indigenous management strategies of HG and dynamic of traditional knowledge related to HG may help to deeply assess home gargardens’ effectiveness in biodiversity conservation.
Article
Full-text available
Species prioritization is a crucial step in any development of conservation strategy, especially for crop wild relatives (CWR), since financial resources are generally limited. This study aimed at: assessing the biodiversity of crop wild relatives in Benin and identifying priority species for active conservation. Data were collected through literature review to establish an exhaustive list of CWR in Benin. Eight prioritization criteria and different prioritization systems were used. The top 50 species obtained by each of these methods were identified and twenty final top CWR were shortlisted as those occurring as priority across methods. A total of 266 plant species belonging to 65 genera and 36 families were identified. The most represented are: Cyperaceae (12.50 %), Leguminosae-Papilionoideae (11.87 %), Convolvulaceae (11.25 %), Poaceae (10.31 %), Asteraceae (7.81 %), Solanaceae (6.87 %) and Dioscoreaceae (5.31 %). Among the 20 species of highest priority for conservation, Manihot glaziovii Mu¨ll. Arg. and Piper guineense Schumach. et Thonn., appeared as the most represented species on top of the list.
ResearchGate has not been able to resolve any references for this publication.