Kasso Daïnou

Based on recent taxonomic and molecular tools, the Walter's duiker (Philantomba walteri Colyn, 2010), endemic to the Dahomey Gap in West Africa, has been recognized as a new species in 2010. This species is largely hunted and may already be threatened by extinction. This review paper aims to synthesize the current knowledge on this species, coverin...

Seeds contained in the soil bank can be too small to quantify visually. Concerned timber species are usually identified after germination trials in the nursery, which is time consuming. This study explores a new approach based on near infrared hyperspectral imaging (NIR-HSI) coupled with chemometric tools. It focuses on the soil seed bank of the ce...

Khaya (Meliaceae) is a widespread genus of trees distributed from the tropical forests of Africa to Madagascar and the Comoros. Khaya species are very close morphologically and some contain considerable phenotypic and ecological diversity, raising the question of their delimitation: this is the case of Khaya anthotheca s.l. (sensu lato, including K...

Tree growth and mortality are two central processes in mixed and structurally complex moist tropical forests, yet accurate estimates of the variables needed to model them remain sparse and scattered. It is thus still difficult to predict forest evolution at a local scale and build reliable management plans. To help fill this gap, for 1–7 years we a...

Regeneration of tropical forest occurs naturally and mainly through early secondary succession by soil seed banks. Here, we analyzed seed bank variation in density and diversity along a degradation gradient. We also explored the relationship (similarity in composition) between the seed and seedling banks and the overstory vegetation. The investigat...

L’ouvrage aborde les différentes étapes d’un programme sylvicole : récolte et gestion des semences, construction et gestion des pépinières, modalités d’installation et de conduite des plantations. Une estimation des coûts et de la rentabilité de telles plantations est également fournie. Enfin, le livre décrit en détail l’itinéraire sylvicole de 50...

L’intensification des activités humaines, la demande croissante en protéines animales suite à l’explosion démographique et le braconnage organisé (ivoire, écailles de pangolins,...) entrainent une pression croissante sur la faune sauvage des forêts d’Afrique centrale. Pour répondre à ces menaces, des stratégies sont mises en place aux échelles nati...

The timber of the species Lophira alata (azobe) is very popular for outdoor constructions, which favours its overexploitation and illegal logging. We sampled individuals from Liberia, Ivory Coast, Ghana, Nigeria, Cameroon, Gabon, Congo Brazzaville and Republic Democratic of Congo to discover new nuclear and plastidial SNP and INDEL loci through res...

Negative short-term impact of logging on great ape distribution has been investigated but very little information is available on the long-term impacts of selective logging and management plans on ape habitats at a broader scale. We carried out a habitat suitability analysis using the presence data of great apes to identify the spatial relationship...

In the pantropical mimosoid legume genus Parkia, taxonomic classification has remained controversial in Africa due to clinal phenotypic variations. Three species (P. biglobosa, P. bicolor, and P. filicoidea) are currently recognized, ranging from West to East Africa, with partially overlapping ranges across different floristic regions. However, add...

Temporal and spatial patterns in flowering phenology were assessed for eight tropical African tree species. Specifically, the frequency and seasonality of flowering at seven sites in central Africa were determined using field data, graphical analysis and circular statistics. Additionally, spatial variation in the timing of flowering across species...

La durabilité de l’aménagement des forêts naturelles d’Afrique centrale est tributaire d’une connaissance approfondie de la dynamique démographique des populations d’arbres commerciaux. Cette dynamique est étudiée dans des dispositifs destinés à être suivis sur le long terme, dénommés parcelles et sentiers. Si la démarche méthodologique d’installat...

Species delimitation remains a crucial issue for widespread plants occurring across forest-savanna ecotone such as Lophira (Ochnaceae). Most taxonomists recognize two parapatric African tree species, widely distributed and morphologically similar but occurring in contrasted habitats: L. lanceolata in the Sudanian dry forests and savannahs and L. al...

Premise: Few studies have addressed the evolutionary history of tree species from African savannahs. Afzelia contains economically important timber species, including two species widely distributed in African savannahs: A. africana in the Sudanian region and A. quanzensis in the Zambezian region. We aimed to infer whether these species underwent r...

How the Central African rain forests have been affected by climatic fluctuations of the Quaternary remains debated. Phylogeographical studies have shown that tree species from western Central Africa often display spatially congruent genetic discontinuities, supporting the hypothesis that the forest was previously fragmented. Extensive seed dispersa...

Tropical forests in Central Africa host unique biodiversity threatened by human degradation of habitats and defaunation. Forests allocated to conservation, production and community management are expected to have different conservation values. Here, we aimed to identify the determinants of the conservation value of tropical forests in southeastern...

Adaptive evolution is a major driver of organism diversification, but the links between phenotypic traits and environmental niche remain little documented in tropical trees. Moreover, trait‐niche relationships are complex because a correlation between the traits and environmental niches displayed by a sample of species may result from (a) convergen...

Few studies have addressed the evolutionary history of tree species from African savannahs at large geographic scales, particularly in the southern hemisphere (Zambezian region). Afzelia (Fabaceae: Caesalpinioideae) contains economically important timber species, including two species widely distributed in African savannahs: A. africana in the Suda...

Introduction. En raison de la diminution des ressources en bois d'oeuvre tropicaux, il convient d'améliorer les connaissances sur les espèces ligneuses en vue de développer des politiques d'exploitation réellement durables. Reconnu pour la grande qualité de son bois, Cylicodiscus gabunensis Harms (Fabaceae-Caesalpinioideae) est une essence à haute...

Cola nitida is a West African tree, commonly used for pharmaceutical purposes. In Benin, the species is used for many purposes ranging from traditional rituals to domestic consumption. Nowadays, the species, as well as its offspring, are hardly encountered. So far, research on the species focused on a single domain such as ethnobotany and phytochem...

Spatial pattern (SP) and neighbourhood distance (ND) of trees are crucial for pollination services, in particular for dioecious species. However, land use types through human disturbances may affect the natural SP and ND and possibly have a negative effect on pollination services. Though several studies have focused on the effect of land use types...

In tropical Africa, evidence of widely distributed genera transcending biomes or habitat boundaries has been reported. The evolutionary processes that allowed these lineages to disperse and adapt into new environments are far from being resolved. To better understand these processes, we propose an integrated approach, based on the eco-physio-morpho...

The role of evolution in biological invasion studies is often overlooked. In order to evaluate the evolutionary mechanisms behind invasiveness, it is crucial to identify the source populations of the introduction. Studies in population genetics were carried out on Robinia pseudoacacia L., a North American tree which is now one of the worst invasive...

Cette étude évalue l’abondance des graines d’Erythrophleum suaveolens dans la banque de semences du sol des forêts denses humides d’Afrique centrale. Les travaux ont été menés au Nord-Congo dans deux types forestiers : la forêt à Celtis sur des sols argilo-sableux à sablo-argileux et la forêt à Manilkara sur des sols sableux. Les tiges d’E. suaveol...

Edited journal version available on request. The sustainability of the polycyclic logging system in tropical forests has been increasingly questioned for a variety of reasons, and particularly in central Africa as commercial species, mostly light-demanding long-lived pioneer species, usually fail to recover a stable number of large trees after exp...

Tropical rain forests support a remarkable diversity of tree species, questioning how and when this diversity arose. The genus Guibourtia (Fabaceae, Detarioideae), characterized by two South American and 13 African tree species growing in various tropical biomes, is an interesting model to address the role of biogeographic processes and adaptation...

This study evaluates the characteristics of soil seed bank in two types of central African rainforests: Celtis forest on clay soils and Manilkara forest on sandy soils. In each study site, 30 samples were collected per soil layers (litter, 0–5 cm, 5–10 cm and 10–20 cm depth). The species diversity and abundance of the soil seed bank were estimated...

Size at reproduction is a key aspect of species life history that is relatively understudied for long-lived tropical trees. Here, we quantified reproductive diameter for 31 major timber species across 11 sites in Cameroon, Congo, and Central African Republic. Specifically, we examined whether (1) between-species variability is correlated with other...

Technical guide about Acacia auriculiformis plantation.

Characterization of the ecology of endangered timber species is a crucial step in any forest management strategy. In this study, we described the animal communities involved in seed dispersal and predation of a high-value timber species Guibourtia tessmannii (Fabaceae; Detarioideae), which is newly listed on Appendix II of CITES. We compared the an...

Introduction. De nos jours, la gestion des ressources forestières ne se focalise plus sur l’exploitation exclusive du bois d’œuvre, mais prend également en considération les produits forestiers non ligneux. Entandrophragma cylindricum (Sprague) Sprague, de son nom commercial « sapelli/sapele », de la famille des Meliaceae, illustre parfaitement cet...

DNA-based techniques are helpful in characterising hybridisation patterns in plant species. To be efficient in disentangling species boundaries and interspecific gene flow, it is recommended to combine various methodologies and types of markers. Here, we used different analytical tools (algorithms implemented in Structure, Tess, NewHybrids and HIes...

La rythmicité intra-annuelle de la crois- sance diamétrique des arbres n’est connue que pour très peu d’espèces tropicales africaines. Dans cet article, une combinaison de méthodes expéri- mentant le marquage cambial séquen- tiel, l’analyse anatomique et la mesure des cernes a été utilisée pour détermi- ner la périodicité et les variations de la cr...

Tropical forests are major providers of natural resources and ecosystem services but their ecological functions are at threat, due to increasing human pressure linked to economic development. The identification of priority areas for conservation is crucial for land use planning to ensure the protection of biodiversity and ecological function. Intac...

Microsatellite primers (simple sequence repeats [SSRs]) were developed in Guibourtia ehie (Fabaceae, Detarioideae) to study population genetic structure and the history of African vegetation. We isolated 18 polymorphic SSRs from a nonenriched genomic library. This set of primer pairs was tested on four populations, and the results showed two to 16...

Restriction associated DNA sequencing was conducted on two genetically independent individuals of Iroko, Milicia excelsa, for the discovery of nuclear SNPs. Ninety-four samples, well-distributed over the natural range and including timber DNA, were screened at 138 loci on a MassARRAY iPLEX system. Amplification success was high and 77 loci were sel...

The sustainable management and conservation of biodiversity require reliable species delimitation. However, in tropical forests, species delimitation is a recurrent problem. This is the case in the African trees of the genus Khaya (African mahogany, Meliaceae), whose delimitation varied widely since the publication of the first species. Currently,...

Introduction. Nowadays, the management of forest resources is no longer focused on the exclusive extraction of timber; it must also consider the use and management of non-timber forest products. Entandrophragma cylindricum (Sprague) Sprague, whose trade name is “sapelli/sapele”, and which belongs to the Meliaceae family, perfectly illustrates this...

Background Species delimitation in closely related plant taxa can be challenging because (i) reproductive barriers are not always congruent with morphological differentiation, (ii) use of plastid sequences might lead to misinterpretation, (iii) rare species might not be sampled. We revisited molecular-based species delimitation in the African genus...

Polyploidy has rarely been documented in rain forest trees but it has recently been found in African species of the genus Afzelia (Leguminosae), which is composed of four tetraploid rain forest species and two diploid dry forest species. The genus Afzelia thus provides an opportunity to examine how and when polyploidy and habitat shift occurred in...

Species distribution within plant communities results from both the influence of deterministic processes, related to environmental conditions, and neutral processes related to dispersal limitation and stochastic events, the relative importance of each factor depending on the observation scale. Assessing the relative contribution of environment nece...

Le système de certifcation FSC (Forest Stewardship Council) vise à promouvoir la gestion durable des forêts. Il repose sur un ensemble de normes dont une est particulièrement complexe à mettre en œuvre en Afrique Centrale, le principe 9 traitant des Hautes Valeurs de Conservation (HVC). Ce principe devrait être interprété aux échelons nationaux afn...

Dendrometric parameters such as tree DBH, height, crown diameter and size characteristics of leaves and fruit production collected from Vitellaria paradoxa subsp. growing in three land use types in Pendjari Biosphere Reserve (PBR) were analyzed. A total of 36 circular plots of 15 m diameter were randomly set in the three main land use sites of the...

Premise of the study: Nuclear microsatellites (nSSRs) were designed for Guibourtia tessmannii (Fabaceae, Caesalpinioideae), a highly exploited African timber tree, to study population genetic structure and gene flow. Methods and Results: We developed 16 polymorphic nSSRs from a genomic library tested in three populations of G. tessmannii and two po...

Palaeoecological and archaeological studies have demonstrated that human populations have long inhabited the moist forests of central Africa. However, spatial and temporal patterns of human activities have hardly been investigated with satisfactory accuracy. In this study, we propose to characterize past human activities at local scale by using a s...

In natural forests of Central Africa, several studies indicate a dramatic decrease in commercial trees, including species of concern for conservation. Enrichment planting with these species will favor both the long-term recovery of their populations and biodiversity conservation in logged forests. In this study, we analyzed the survival and growth...

Owing to the reduction of population density and/or the environmental changes it induces, selective logging could affect the demography, reproductive biology and evolutionary potential of forest trees. This is particularly relevant in tropical forests where natural population densities can be low and isolated trees may be subject to outcross pollen...

Modéliser la croissance de quatre essences pour améliorer la gestion forestière au Cameroun

Light is of primary importance in structuring tropical tree communities. Light exposure at seedling and adult stages has been used to characterize the ecological profile of tropical trees, with many implications in forest management and restoration ecology. Most shade-tolerance classification systems have been proposed based on empirical observatio...

The identification of seed dispersers and predators is essential to understand the effect of anthropogenic disturbances, and the associated defaunation process, on tropical forest dynamics in Central Africa. In this study, the animals involved in seed predation and dispersal of Dacryodes normandii (Burseraceae), an endozoochorously dispersed tree s...

Tropical forests of Central Africa constitute the second most important block of moist forest of the world. Little is known, however, about past vegetation in this region that remains underexplored (Vleminckx et al. 2014; Morin-Rivat et al. 2014). Determining the past specific composition of these forests could allow bringing insights into their ev...

En Afrique centrale, l’aménagement fores- tier repose sur une méthode de simulation de la production forestière peu précise, susceptible d’hypothéquer la durabilité de l’exploitation. L’objectif de cette étude est d’améliorer la prédiction de la crois- sance pour quatre essences commerciales importantes en Afrique centrale. Le dispo- sitif d’étude...

1. Plant functional traits, in particular specific leaf area (SLA), wood density and seed mass, are often good predictors of individual tree growth rates within communities. Individuals and species with high SLA, low wood density and small seeds tend to have faster growth rates. 2. If community-level relationships between traits and growth have gen...

Palaeoecological and archaeological studies have demonstrated that human populations have long inhabited the moist forests of central Africa. However, spatial and temporal patterns of human activities have hardly been investigated with satisfactory accuracy. In this study, we propose to characterize past human activities at local scale by using a s...

Background and aims – Prior to European colonisation of Central Africa, human populations were dispersed through the forests, where they practiced slash-and-burn cultivation. From the 19th century they were progressively concentrated in villages along roads, leaving large areas of forest derelict. In south-western Cameroon, and elsewhere in Central...

To develop silvicultural guidelines for high-value timber species of Central African moist forests, we assessed the performance of the pioneer Milicia excelsa (iroko, Moraceae), and of the non-pioneer light demander Pericopsis elata (assamela, Fabaceae) in logging gaps and in plantations in highly degraded areas in south-eastern Cameroon. The survi...

While most past studies have emphasized the relationships between specific forest stands and edaphic factors, recent observations in Central African moist forests suggested that an increase of slash-and-burn agriculture since 3000-2000 BP (Before Present) could be the main driver of the persistence of light-demanding tree species. In order to exami...

• Microsatellites were developed in the vulnerable African rainforest tree Afzelia bipindensis to investigate gene flow patterns. • Using 454 GS-FLX technique, 16 primer sets were identified and optimized, leading to 11 polymorphic and readable markers displaying each six to 25 alleles in a population. Up to four alleles per individual were found i...