References of "Doucet, Jean-Louis"
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See detailNature+ asbl - Rapport d'activités 2011
Federspiel, Michèle; Bourland, Nils ULg; Daïnou, Kasso ULg et al

Report (2012)

En 2011, Nature+ a rencontré ses missions, notamment : en mettant en oeuvre deux projets de foresterie communautaire financés par des bailleurs internationaux ; en participant à la gestion durable de près ... [more ▼]

En 2011, Nature+ a rencontré ses missions, notamment : en mettant en oeuvre deux projets de foresterie communautaire financés par des bailleurs internationaux ; en participant à la gestion durable de près de 2 millions d’hectares de forêts denses humides tropicales grâce à nos collaborations avec des sociétés forestières engagées dans les processus de certification FSC ; en accueillant dans nos divers projets 12 étudiants en fin de cursus universitaire ainsi que 8 doctorants. 7 universités différentes ont ainsi reçu un appui administratif, technique et scientifique de Nature+. [less ▲]

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See detailScaphandre La science rencontre l'art: L'art
Haubruge, Eric ULg; Bay, Daniel ULg; Semal, Jean et al

in Haubruge, Eric; Bay, Daniel; Semal, Jean (Eds.) Scaphandre La science rencontre l'art (2012)

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See detailLes 5 arbres protégés du Gabon
Moumbogou, Carl; Meunier, Quentin; Ogoula Ikinda, L. B. et al

Learning material (2012)

Ces cinq essences forestières sont réputées pour la qualité de leur bois et ont fait l’objet d’exploitation dans le pays. Elles font également partie intégrante de la vie des communautés rurales du Gabon ... [more ▼]

Ces cinq essences forestières sont réputées pour la qualité de leur bois et ont fait l’objet d’exploitation dans le pays. Elles font également partie intégrante de la vie des communautés rurales du Gabon, tant pour leurs vertus alimentaires et médicinales que pour leur importance dans les rites initiatiques traditionnels. [less ▲]

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See detailEcology and management of Pericopsis elata (Harms) Meeuwen (Fabaceae) populations: a review
Bourland, Nils ULg; Kouadio, Yao Lambert; Fétéké, Fousséni et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2012), 16(4), 486-498

Pericopsis elata (Fabaceae) is a valuable timber species occurring in moist semi-deciduous African forests. While it is at present substantially reduced, the tree’s natural distribution previously covered ... [more ▼]

Pericopsis elata (Fabaceae) is a valuable timber species occurring in moist semi-deciduous African forests. While it is at present substantially reduced, the tree’s natural distribution previously covered several distinct areas from Côte d’Ivoire to the Democratic Republic of Congo. This species has been logged since the second half of the 20th century. Because it suffers from a lack of regeneration, P. elata is now included in CITES Appendix II and is recorded as “Endangered A1cd” on the IUCN Red List. As with other long-lived light-demanding species, the survival of P. elata may have been favored by important disturbances that occurred in the Congo Basin during the last millennia. While both international trade and industrial uses of the wood of P. elata are well documented, information about its ecology are very sparse or contradictory, and even absent in some cases (e.g., regarding its effective flowering diameter). Furthermore, data describing the management of P. elata are scarce, including potential solutions to compensate for the deficit of natural regeneration. Along the same lines, genetic studies still remain at an early stage and only vague hypotheses have been offered to explain the origins of the tree’s populations. We emphasize the need for new research on those topics. Further studies would be useful in deciding whether P. elata populations can continue to be logged without the species being threatened with extinction. Finally, such research needs to target effective and inexpensive management procedures that could secure the future of the species in a logging context. [less ▲]

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See detailPhenological patterns in a natural population of a tropical timber tree species, Milicia excelsa (Moraceae): evidence of Isolation By Time and its interaction with feeding strategies of dispersers
Daïnou, Kasso ULg; Laurenty, Eric; Mahy, Grégory ULg et al

in American Journal of Botany (2012), 99(9), 1-11

Population genetic structuring over limited timescales is commonly viewed as a consequence of spatial constraints. Indirect approaches have recently revealed existence of reproductive isolation due to ... [more ▼]

Population genetic structuring over limited timescales is commonly viewed as a consequence of spatial constraints. Indirect approaches have recently revealed existence of reproductive isolation due to flowering time (the so-called isolation by time, IBT). Since phenological processes can be subject to selection, the persistence of flowering asynchrony may be due to opposing selective pressures during mating, dispersal and regeneration phases. Our study aimed to investigate phenology, fruit-handling by animals and their interaction, in a timber tree species, Milicia excelsa. We analyzed phenological data collected over a 6-year period on 69 genotyped trees in a Cameroonian natural rainforest complemented by data from germination trials and field observations of dispersers. Initiation of flowering correlated with variation in temperature and relative humidity, but was also affected by genetic factors: pairwise differences in flowering time between nearby individuals correlated with kinship coefficient, and earliness of flowering remained stable over time. A decrease in mean seed production per fruit with increasing flowering time suggests selection against late bloomers. However, germination rate was not affected by seed collection date, and the main seed disperser, the bat Eidolon helvum, seemed to increase in abundance at the end of the reproductive season, and preferred trees in open habitats where early and late bloomers are expected. The pairwise approach performs well to detecting IBT. The persistence of different mating pools in such a case may result from a trade-off between selective forces during the mating and seed dispersal processes. [less ▲]

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See detailA commented checklist of woody plants in the Northern Republic of Congo
Gillet, Jean-François ULg; Doucet, Jean-Louis ULg

in Plant Ecology and Evolution (2012), 145(2), 258-271

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See detailIdentité et écologie des espèces forestières commerciales d'Afrique Centrale: le cas de Milicia spp.
Daïnou, Kasso ULg; Doucet, Jean-Louis ULg; Sinsin, Brice et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2012), 16

Le terme iroko regroupe les deux espèces du genre africain Milicia et désigne le bois qui en est dérivé. Malgré une importance économique reconnue depuis plus de deux siècles et une diminution sensible ... [more ▼]

Le terme iroko regroupe les deux espèces du genre africain Milicia et désigne le bois qui en est dérivé. Malgré une importance économique reconnue depuis plus de deux siècles et une diminution sensible des densités de population du fait de l'exploitation, les connaissances scientifiques utiles à la gestion durable de l'iroko font défaut, particulièrement en Afrique Centrale. L'existence même d'une spéciation au sein du genre Milicia mérite d'être revérifiée: les caractères utilisés pour séparer les deux taxons M. excelsa (Welw.) C.C. Berg et M. regia (A. Chev.) C.C. Berg sont peu consistants et une révision de ces traits distinctifs permettrait de réétudier le niveau de vulnérabilité des populations de Milicia spp., et donc de revoir les stratégies de gestion de ce groupe taxonomique. M. regia n'a fait l'objet que de rares études écologiques tandis que M. excelsa, plus largement distribuée, a retenu l'attention scientifique en Afrique de l'Ouest, dans une certaine mesure. Dans tous les cas, les traits d'histoire de vie conditionnant la diversité génétique et le taux de régénération naturelle méritent d'être identifiés ou mieux décrits. En particulier, les connaissances existantes sur les populations reproductrices, les facteurs régulant la floraison, les patrons de fructification et de dispersion des diaspores, ainsi que d'autres caractères qui amènent à décrire l'iroko comme un arbre pionnier (besoins en lumière, dormance des graines) devraient être mieux documentés. Enfin, la dynamique même des populations naturelles de juvéniles devra également être mieux caractérisée. En l'absence de données fines en écologie, la durabilité de nombreuses ressources ligneuses commerciales est tributaire d'actions sylvicoles, lesquelles peuvent être coûteuses et ne pas être garanties sur le long terme. [less ▲]

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See detailMathematical formulation and exact solution for landing location problem in tropical forest selective logging, a case study in Southeast Cameroon
Philippart, Julien ULg; Minghe, Sun; Doucet, Jean-Louis ULg et al

in Journal of Forest Economics (2012), 18

In Central Africa, creating forest roads and skid trails is one of the most costly and environmentally damaging operations for the forest's ecosystem. An optimized road network is essential for reducing ... [more ▼]

In Central Africa, creating forest roads and skid trails is one of the most costly and environmentally damaging operations for the forest's ecosystem. An optimized road network is essential for reducing construction costs and improving the sustainable management of timber resources. The location of landings is vital in the development of a future forest road network. In this study, a binary integer programming model similar to the uncapacitated facility location problem is formulated to optimize the locations of the landings. The model is applied to selective logging in Central Africa and tested on an annual logging zone in Southeast Cameroon. The results are compared to that of manual road planning, the currently used method. [less ▲]

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See detailWill community forestry put an end to Flegt in Cameroon?
Beauquin, Antoine; Vermeulen, Cédric ULg; Julve, Cécilia et al

in Lettre de l'ATIBT (La) (2012), 34

Community forests, pillars of participatory forest management in Central Africa, have been incorporated into the Cameroon VPA, which is to come into force by the end of 2012. However, a recent study ... [more ▼]

Community forests, pillars of participatory forest management in Central Africa, have been incorporated into the Cameroon VPA, which is to come into force by the end of 2012. However, a recent study suggests that this integration might disturb the good implementation of the VPA. In consequence, community forests indirectly threaten the export of all Cameroonian timber. [less ▲]

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See detailEcological characterization of Lophira alata (Ekki), a vulnerable timber tree species, in order to develop silvicultural effective strategies
Biwole, Achille ULg; Doucet, Jean-Louis ULg

Poster (2011, December 02)

Ekki, Lophira alata Banks ex C.F.Gaertn., is an African timber species occurring in tropical rainforests. Of important commercial value, this species is logged for its excellent timber properties and has ... [more ▼]

Ekki, Lophira alata Banks ex C.F.Gaertn., is an African timber species occurring in tropical rainforests. Of important commercial value, this species is logged for its excellent timber properties and has been classified by the IUCN as «vulnerable" species. As for many other tropical tree species, the commercial exploitation of Ekki is confronted to an insufficient knowledge about the species’ ecological profile. With a distribution range limited to the Guinea-Congolian region, Ekki often displays insufficient natural regeneration, but the biotic and abiotic factors explaining this deficiency have been hardly characterized. This lack of knowledge makes it difficult to model the population dynamics on the long term. The reproductive biology of Ekki and the genetic variability of its population remains poorly studied too. To address this situation, a fundamental and applied research is being undertaken in the forest concessions managed by Wijma Cameroun SA., covering over 250,000 hectares of rainforest in Southern Cameroon. This study aims to answer four essential questions: (1) what is the phylogenetic relationship between L. alata and L. lanceolata, (2) how paleoclimate and human disturbances impact its distribution and abundance, (3) how to these populations respond to logging over several rotation periods, (4) does logging promote or inhibit the natural regeneration of the species. Several study devices have thus been installed to collect the data needed to improve the characterization of Ekki’s ecology and to conceive silvicultural strategies. [less ▲]

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See detailRole of western lowland gorilla (Gorilla gorilla gorilla) to dispersal and regeneration of commercial trees in South-East Cameroon
Petre, Charles-Albert ULg; Tagg, Nikki; Beudels-Jamar, Roseline et al

Poster (2011, December 01)

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See detailDynamique forestière et enrichissements forestiers. Site de Mbang. Rapport n° 7.
Doucet, Jean-Louis ULg; Amandé, Jean; Essik, Jean-Marie et al

Report (2011)

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See detailSeed dispersal by Western lowland gorillas (G.g.gorilla) in South East Cameroon
Petre, Charles-Albert ULg; Tagg, Nikki; Beudels-Jamar, Roseline et al

in Primate Tidings (2011), 25

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See detailPreliminary insight into seed effectiveness of western lowland gorilla (Gorilla g.gorilla)
Petre, Charles-Albert ULg; Tagg, Nikki; Beudels-Jamar, Roseline et al

in Primate Tidings (2011, December), 25

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See detailRole of western lowland gorilla (Gorilla gorilla gorilla) to dispersal and regeneration of commercial trees in South-East Cameroon
Petre, Charles-Albert ULg; Tagg, Nikki; Beudels-Jamar, Roseline et al

in Primate Tidings (2011), 25

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See detailThe ecological study of an unknown non-timber forest product (NTFP): the African walnut (Coula edulis Baill.)
Moupela, Christian ULg; Vermeulen, Cédric ULg; Lebailly, Philippe ULg et al

Conference (2011, November 15)

Le noisetier d’Afrique, Coula edulis Bail., produit des graines de grande valeur nutritive régulièrement collectées et commercialisées par les populations locales. Toutefois, certains aspects fondamentaux ... [more ▼]

Le noisetier d’Afrique, Coula edulis Bail., produit des graines de grande valeur nutritive régulièrement collectées et commercialisées par les populations locales. Toutefois, certains aspects fondamentaux de son écologie, dont le potentiel de production, la dispersion et la prédation des fruits, demeurent inconnus, ce qui pourrait constituer un frein à sa valorisation. L’étude s’est déroulée au Gabon et s’est attachée à quantifier la production fruitière de l’espèce et à identifier les prédateurs et disperseurs des fruits. Trente-neuf collecteurs circulaires ont été installés sous les houppiers, les données récoltées (nombre et masse des fruits) étant ensuite mises en relation avec le diamètre. Par ailleurs, sept semenciers ont fait l’objet d’observations indirectes grâce à un dispositif de caméras-pièges. Les premières fructifications apparaissent sur les semenciers à partir de 12,3 cm de diamètre. Elle se produit de janvier à avril. Les quantités de fruits sont corrélées positivement au diamètre (r² = 0,493 ; p = 0,001). Dix espèces animales ont été observées aux pieds des arbres en fruits, leur rôle dans la dynamique de population de l’espèce est potentiellement important. [less ▲]

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See detailSylviculture in logging gaps of a Central African rainforest : first synthesis from tests with 11 timber tree species
Daïnou, Kasso ULg; Cerisier, Benjamin; Bourland, Nils ULg et al

in CIRAD Montpellier (Ed.) IUFRO International Conference , Research Priorities in Tropical Silviculture : Towards New Paradigms ?: Abstracts (2011, November 15)

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