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See detailEcological wood anatomy of 155 African tropical hardwoods
Beeckman, Hans; Fayolle, Adeline ULg; Doucet, Jean-Louis ULg et al

Conference (2013, April 19)

In this study we aimed at identifying the anatomical characters expressing life history traits of woody species from the northern Congo Basin. We crosschecked three databases: the botanical inventories ... [more ▼]

In this study we aimed at identifying the anatomical characters expressing life history traits of woody species from the northern Congo Basin. We crosschecked three databases: the botanical inventories produced during the CoForChange project (857 spp.), the database of life history traits established by the CIRAD (France) and GxABT (Belgium) (464 spp.), and the anatomical database Inside Wood (761 spp. and genera for tropical Africa). A total of 155 shared species was obtained. We performed correspondence analyses between the anatomical characters and two main groups of traits: leaf phenology and light-requirement. Results showed: (i) that wood anatomy is involved in leaf phenology and light-requirement in a significant way (7.56% of the variance on axe1), (ii) that evergreenness was correlated to IAWA characters 14 to 18 (scalariform perforation plates, e.g. Olacaceae) and deciduousness to characters 118 to 122 (storied structures, e.g. Malvaceae and Meliaceae), (iii) that pioneer (P) and non-pioneer light-demanding (NPLD) species showed similar traits but were different from shade-tolerant (ST) species, (iv) that deciduous and evergreen species showed separate distributions, and (v) that wood anatomy validated the well documented strong correlation between evergreen species and ST species, with an inversion of the tendency for deciduous species correlated to P and NPLD species. We conclude that anatomical characters can be used as indicators of life history traits in species-rich biomes. Further investigations are needed to increase the input of wood anatomy in explaining the life history traits in African tropical species. [less ▲]

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See detailEcological, morphological and allozymic differentiation between diploid and tetraploid knapweeds (Centaurea jacea) from a contact zone in the Belgian Ardennes
Hardy, O. J.; Vanderhoeven, SONIA ULg; De Loose, M. et al

in New Phytologist (2000), 146(2), 281-290

In the northeastern part of Belgium, the Centaurea jacea complex shows extensive morphological variation and is represented by a diploid (2n = 22) and a tetraploid (2n = 44) cytotype. Polysomic ... [more ▼]

In the northeastern part of Belgium, the Centaurea jacea complex shows extensive morphological variation and is represented by a diploid (2n = 22) and a tetraploid (2n = 44) cytotype. Polysomic inheritance of allozyme markers in the tetraploids, suggesting autopolyploidy, is here demonstrated for the first time. In order to test whether the tno cytotypes occupy distinct habitats and possess different gene pools, patterns of allozymic and morphological variation were investigated in relation to ploidy level and site characteristics in 26 populations from the Belgian Ardennes. The two cytotypes showed a parapatric distribution, the diploids occurring at higher elevations (mostly above 500 m) than the tetraploids (mostly below 500 m). Three mixed populations were found near the contact zone of the two cytotypes. Within the mixed populations no triploid plant and no evidence for gene flow between cytotypes were found, despite widely overlapping flowering periods. The two cytotypes can be distinguished on the basis of morphological traits and enzymatic gene pools. The congruence of morphological and allozymic variation with chromosome numbers suggests a secondary contact between the two cytotypes with limited gene flow between them. The origin and persistence of the parapatric distribution are discussed. [less ▲]

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See detailEcologie chimique d’Eisenia fetida et son implication dans le lombricompostage
Zirbes, Lara ULg

Conference given outside the academic context (2009)

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See detailEcologie chimique d'Eisenia fetida et son implication dans le lombricompostage
Zirbes, Lara ULg

Master's dissertation (2007)

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See detailEcologie de la loutre (Lutra lutra) dans le Marais Poitevin 1. Etude de la consommation d'anguilles
Libois, Roland ULg; Rosoux, René

in Vie et milieu (1989), 39(3-4), 191-197

From 1982 to 1987, 165 otter scats samples were collected in the Marais Poitevin area (Western France). Eel was present in 158 of them. In our study area, eel was the main prey of the otter: its relative ... [more ▼]

From 1982 to 1987, 165 otter scats samples were collected in the Marais Poitevin area (Western France). Eel was present in 158 of them. In our study area, eel was the main prey of the otter: its relative frequency of occurrence in the otter's faeces amounted to 32.7% and its relative abundance to 40%. We did not find any dietary seasonal variation in terms of eel size or eel number. Prey size ranged from 9 to 65 cm (mean = 28 cm; n = 490) but mostly (75 %) less than 30 cm. In contrast these small individuals made up only 30% of the total eel weight represented by remains in the faeces. Eel size frequency distribution was compared in the otter's diet and in the rivers (data from Legault, 1987: electrofishing and fishing tackles). No significant difference was found, indicating that there was no selection at all in terms of prey size. [less ▲]

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See detailEcologie de la loutre (Lutra lutra) dans le Marais Poitevin 2. Aperçu général du régime alimentaire
Libois, Roland ULg; Rosoux, René

in Mammalia (1991), 55(1), 35-47

From 1982 to 1987, 165 otter spraints samples were collected in the Marais Poitevin area (Western France). Eel is the main prey whichever way the results are presented: relative occurrence, relative ... [more ▼]

From 1982 to 1987, 165 otter spraints samples were collected in the Marais Poitevin area (Western France). Eel is the main prey whichever way the results are presented: relative occurrence, relative abundance or relative biomass. Despite their high frequency or abundance in the spraints, other preys such as Atherina, mosquito-fish, stickelback, stone loach, bluegill or invertebrates, are quite negligible as far as biomass is considered. In turn, less frequent bigger preys (mammals, tenches) are of geater importance. Except for cyprinid fishes, more frequent in spring, no marked seasonal variations were found in the otters diet. [less ▲]

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See detailEcologie de la loutre (Lutra lutra) et conservation de ses habitats riverains
Libois, Roland ULg

in Actes du 1er colloque international "gestion et préservation des ressoures en eau" (2004, September)

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See detailEcologie de la loutre dans le Marais Poitevin III. Variations du régime et tactique alimentaire.
Libois, Roland ULg; Rosoux, René; Delooz, Etienne

in Cahiers d'Ethologie (1991), 11(1), 31-50

During the spring 1988, spraint samples were collected on the banks of 3 watercourses (one river and two canals) crossing the Marais Poitevin. Their general characteristics (flow rate, conductivity ... [more ▼]

During the spring 1988, spraint samples were collected on the banks of 3 watercourses (one river and two canals) crossing the Marais Poitevin. Their general characteristics (flow rate, conductivity, hydrographic regime) are quite different. The fish community of the two canals was sampled by electrofishing and we estimated the relative abundance of the different fish species. After a check of the reliability of our spraint analysis technique (feeding trials with captive otters), we made an estimate of the relative abundance of the prey items in the otters diet and an assessment of the length and of the weight of each individual fish preyed upon. They are indeed very strong length-weight correlations in fish and also close relationships between the length of some skull bones and the total length od a fish. The diet is mostly made up by the eel. It comprises also a great variety of other fish species, nearly all that were observend in the habitat. Much frogs, some snakes, birds, mammals, insects and crustaceans were also discovered. They are only slight diet differences between the main watercourses which probably are related to the characteristics of their fish fauna (e.g. much more sticklebacks when waters are becoming brackish; big amount of Atherina in salt marshes). No marked variations were found during a normal summer but fish is obviously less eaten during a severe drought. Comparing the frequency-distributions of fish in the diet and in the habitat, we found no selective predation in respect with fish (eel, cyprinids) size. From that point of view, the otter display a generalistic-opportunistic pattern of foraging. As far as the relative abundance of the various species is considered, otters take much less roaches and much more eels and tenches than present in the habitat. It remains to be seen if that is the consequence of a 'deliberate choice' or of a peculiar way of underwater huntig. A fact is that the otter principally eats bottom living fishes. [less ▲]

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See detailEcologie des tritons au Pays de Herve: influence des habitats à plusieurs échelles
Denoël, Mathieu ULg; Perez, Amélie; Ficetola, G. Francesco

in Echo des Rainettes (2012), 10

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See detailEcologie du paysage : patrons / processus / design
Mahy, Grégory ULg

Scientific conference (2010, December 14)

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See detailEcologie du paysage, anthropisation en Afrique tropicale, instruments et études de cas
Vranken, Isabelle ULg

Scientific conference (2013, November)

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See detailEcologie du paysage: cibler la configuration et l’échelle spatiale.
Bogaert, Jan ULg; Mahamane, A

in Annales des Sciences Agronomiques du Bénin (2005), 7(1), 39-68

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See detailEcologie du paysage: concepts, méthodes et applications (F. Burel, J. Baudry).
Bogaert, Jan ULg

in Landscape & Urban Planning (2001), 55(1), 70-72

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See detailEcologie et distribution des espèces de Culicoides Latreille 1809 (Diptera : Ceratopogonidae) à proximité d’une exploitation bovine en Belgique
Zimmer, Jean-Yves ULg; Losson, Bertrand ULg; Saegerman, Claude ULg et al

in Annales de la Société Entomologique de France (2009), 45(3), 393-400

Bluetongue is a non-contagious disease that affects domestic and wild ruminants. Since its spreading to Northern Europe in 2006, this viral epizooty caused considerable economical losses on the ovine and ... [more ▼]

Bluetongue is a non-contagious disease that affects domestic and wild ruminants. Since its spreading to Northern Europe in 2006, this viral epizooty caused considerable economical losses on the ovine and bovine livestock. The biological vectors of the bluetongue virus (BTV) are biting midges belonging to the genus Culicoides. Many elements still remain unknown about their biology, physiology, ecology and distribution. This study shows that these biting midges are much more abundant on farm level than in the nearby meadows; these last ones nevertheless present a much more specifi c diversity. So possibility of migration between the meadow and the farm is voiced for the C. chiopterus and C. dewulfi species. Females are much more represented than males for the farm and the meadow alike. The physiology observation of these ones is realized throughout the study. [less ▲]

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See detailEcologie, diversité spécifique et abondance des petits mammifères de la ville de Cotonou au Bénin (Afrique de l’Ouest)
Houèmènou, Gualbert; Kassa, B.; Libois, Roland ULg

in International Journal of Biological and Chemical Sciences (2014), 8(3), 1202-1213

L’étude de la diversité des petits mammifères de la ville de Cotonou (Bénin) selon les types de milieux (habités ou non) a été réalisée du 25 août 2004 au 25 mai 2005 avec interruptions. Les campagnes de ... [more ▼]

L’étude de la diversité des petits mammifères de la ville de Cotonou (Bénin) selon les types de milieux (habités ou non) a été réalisée du 25 août 2004 au 25 mai 2005 avec interruptions. Les campagnes de captures ont été effectuées. Au total, 348 petits mammifères ont été capturés pour un effort de piégeage de 2652 nuits-pièges et 11 espèces comprenant 3 espèces (Rattus rattus, Rattus norvegicus et Mus domesticus) cosmopolites représentant 25% du total et les espèces africaines (Crocidura olivieri, Crocidura sp., Arvicanthis niloticus,Cricetomys gambianus, Dasymys rufulus, Mastomys sp., Gerbilliscus kempi, Taterillus gracilis) représentant 75% du total, ont été inventoriées. La prépondérance de Rattus rattus dans les captures avec 59,8% de Mastomys sp. (13,5%) et de C. olivieri (8,6%) a été notée. Mus domesticus (0,29%), Arvicanthis niloticus (0,86%) et Crocidura sp. (0,86%) sont faiblement représentées. L’indice de diversité de Shannon est de 2,08 dans la ville de Cotonou, de 2,70 dans les milieux non habités et de 1,45 dans les milieux habités où l’on ne trouve quasiment que les rats et souris. Le domaine de l’aéroport (aéroport international de Cotonou) et quelques zones marécageuses, inaccessibles à la population, constituent des zones refuges où l’indice de diversité des petits mammifères est relativement élevé. [less ▲]

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See detailEcologie, dynamique des populations et intérêts économiques du noisetier d'Afrique (Coula edulis Baill.) au Gabon
Moupela, Christian ULg

Doctoral thesis (2013)

Le noisetier d’Afrique (Coula edulis Baill. Olacaceae) est une espèce à usages multiples des forêts denses humides africaines. Elle produit des graines d’une grande valeur nutritive qui sont régulièrement ... [more ▼]

Le noisetier d’Afrique (Coula edulis Baill. Olacaceae) est une espèce à usages multiples des forêts denses humides africaines. Elle produit des graines d’une grande valeur nutritive qui sont régulièrement collectées et commercialisées par les populations locales. Cependant, la valorisation et la domestication de ce produit forestier non ligneux (PFNL) est entravée faute de connaissances précises sur ses caractères reproductifs, son potentiel de production, ses mécanismes de régénération, et les perspectives de développement d'un marché commercial local pour ce produit. Une étude dédiée à cette espèce a donc été entreprise. L’objectif visé était d’améliorer les connaissances sur cette espèce afin de promouvoir sa place dans les systèmes agroforestiers et fournir des informations permettant d'assurer la conservation in situ de la ressource. Les résultats de l'étude montrent que C. edulis est utilisé selon une stratégie de subsistance par les populations, avant tout pour leur autoconsommation et éventuellement pour un revenu qui reste marginal. La reproduction de l'espèce est annuelle, garantissant une disponibilité régulière des fruits. Le diamètre minimum de floraison est de 10,6 cm tandis que le diamètre de fructification régulière est de 23 cm. L’accroissement annuel moyen de l’espèce est de 0,22 cm/an, une valeur similaire à celles observées chez d'autres arbres du sous-bois. La production fruitière est fortement liée au diamètre des tiges et varie d’une année à l’autre. En forêt naturelle, la dissémination de l'espèce est potentiellement assurée par sept espèces frugivores, le principal étant le potamochère, Potamochoerus porcus. Des rongeurs fouisseurs pourraient également jouer un rôle non négligeable dans la dispersion de C. edulis. Par contre, l'éléphant qui était soupçonné de contribuer significativement à la dispersion de l'espèce s'avère n'être qu'un disperseur anecdotique, voire nul. En matière de domestication, les stratégies ne devront pas être basées sur le semis, la germination de C. edulis étant très lente et échelonnée sur plusieurs années, avec des taux de levée très faibles. En revanche, le marcottage aérien a été un succès relatif sur cette espèce et présente l'avantage de maintenir le potentiel génétique de l'arbre multiplié. Les implications de ces résultats aussi bien en termes de gestion durable des peuplements naturels que de domestication de l'espèce dans un contexte agroforestier sont détaillés dans le document. Si l’on désire que les PFNL d’intérêt local comme C. edulis participent substantiellement au développement en milieu rural gabonais, il est essentiel d’orienter ces ressources à la fois dans une stratégie de gestion durable par leur domestication et leur intégration dans le cycle agricole et dans une stratégie de revenu supplémentaire où l’exploitation répond à une demande marchande. [less ▲]

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See detailEcologie, dynamique et gestion des bois morts présents dans les cours d'eau
Mouchet, F.; Piegay, H.; Claessens, Hugues ULg et al

in Parcs & Réserves (2005), 60(1), 14-19

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