Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 21 (0 ULg)
Full Text
See detailEcologie chimique d’Eisenia fetida et son implication dans le lombricompostage
Zirbes, Lara ULg

Conference given outside the academic context (2009)

Detailed reference viewed: 42 (4 ULg)
See detailEcologie chimique d'Eisenia fetida et son implication dans le lombricompostage
Zirbes, Lara ULg

Master's dissertation (2007)

Detailed reference viewed: 113 (17 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 87 (1 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 66 (3 ULg)
Full Text
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)

Detailed reference viewed: 60 (2 ULg)
Full Text
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 ▲]

Detailed reference viewed: 71 (3 ULg)
Full Text
See detailEcologie de reproduction du doussié, Afzelia bipindensis Harms, en forêt dense humide tropicale gabonaise.
Evrard, Quentin ULg

Master's dissertation (2015)

The species Afzelia bipindensis is a precious woody tree known for its wood quality and considered vulnerable by the IUCN. In order to improve the current knowledge gaps about its reproductive ecology ... [more ▼]

The species Afzelia bipindensis is a precious woody tree known for its wood quality and considered vulnerable by the IUCN. In order to improve the current knowledge gaps about its reproductive ecology, the goals of this study are: (1) identify animal dispersers/predators of the seeds with direct and indirect observation methods, (2) quantify the dispersion/predation, (3) test the germination dynamics of those seeds under some circumstances that are likely to influence it, (4) model the growth of juveniles depending upon the access to light. This study was carried out in the forest concession attributed to the Precious Woods society and situated in evergreen forests in East Gabon. After more than 100 hours of direct observation and 3.000 hours of image capture by camera-trap, only four species (Cricetomys emini, Epixerus wilsoni, Protoxerus stangeri and some undetermined Muridae) would be the main animal species to get interested to Afzelia seeds. Those would take more than 90 % of the seeds and would be essentially predators. The results of the germination test revealed a significant influence of the aril on the germination rate. The conservation time and the volume of the seed had also a significant influence over its fitness. Finally, the modeling of growth showed a very low average growth value over time compared to equivalent data collected in Cameroon and a very high mortality rate, probably due to a high predation rate by duikers. [less ▲]

Detailed reference viewed: 16 (0 ULg)
Full Text
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

Detailed reference viewed: 66 (13 ULg)
See detailEcologie du paysage : patrons / processus / design
Mahy, Grégory ULg

Scientific conference (2010, December 14)

Detailed reference viewed: 31 (9 ULg)
Full Text
Peer Reviewed
See detailEcologie du paysage en Afrique subsaharienne
Bogaert, Jan ULg; Andre, Marie ULg

in Tropicultura (2013), 31(1),

Detailed reference viewed: 20 (4 ULg)
Full Text
See detailEcologie du paysage, anthropisation en Afrique tropicale, instruments et études de cas
Vranken, Isabelle ULg

Scientific conference (2013, November)

Detailed reference viewed: 39 (4 ULg)
Full Text
Peer Reviewed
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

Detailed reference viewed: 85 (27 ULg)
Full Text
Peer Reviewed
See detailEcologie du paysage: concepts, méthodes et applications (F. Burel, J. Baudry).
Bogaert, Jan ULg

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

Detailed reference viewed: 176 (26 ULg)
Peer Reviewed
See detailL'écologie du Paysage: un chaînon essentiel pour une gestion multiscalaire de l'hétérogénéité
Mahy, Grégory ULg; Bogaert, Jan ULg; Monty, Arnaud ULg

in Meerts, Pierre (Ed.) Vers une nouvelle synthèse écologique: de l'écologie scientifique au développement durable (2013)

Detailed reference viewed: 47 (11 ULg)
Full Text
See detailEcologie et connaissances ethnozoologiques de quelques espèces d'oiseaux gibiers menaces des ecosytèmes du Sud du Bénin
Lougbegnon, Olou Toussaint ULg

Doctoral thesis (2015)

The natural areas of the south of Benin under subequatorial climate are diversified in resident birds’ species as well as migratory one. Some of them are hunted for food and therapeutic purposes by ... [more ▼]

The natural areas of the south of Benin under subequatorial climate are diversified in resident birds’ species as well as migratory one. Some of them are hunted for food and therapeutic purposes by grassroots communities. The most used are Guttera pucherani, Dendrocygna viduata, Egretta alba, Egretta ardesiaca, Porphyrio alleni et Porphyrio porphyrio. In order to reduce pressure on biodiversity in this part of Benin and to implement the sustainable conservation of birds’ species, this study on ecology and ethno-zoological knowledge of hunted bird species was carried out in the forest areas and the Ramsar sites 1017 and 1018. Field prospections were conducted from 2009 to 2012. The birds’ inventory method used was based on listening point techniques of 15 minutes. Data analysis were analyzed through the computation of bird species abundances, the establishment of maps distribution of the species, the habitat description and the modeling of the climatic niche of these species under climatic models CCCMA (Canadian Centre for Climate Modeling and Analysis) and CSIRO (Commonwealth Scientific and Industrial Research Organization) using MAXENT3.3.2. The ethno-zoological knowledge of the birds species were assessed through individual and groups survey and allowed to calculate the use values of the different part of the birds’ species according to the socio-cultural groups, sex and age. Moreover a logistic binary regression was carried out to determine the socio-economic factors which affect bird species exploitation by the grassroots communities. Results of modeling showed that among the variables selected for the prediction of the climatic models, distance from river, altitude appeared as the environmental variable which more contributed to the prediction of the models (with an average of 74.32 % and 12.94%). Projection under CCCMA and CSIRO in 2050, showed a progression of the favorable areas to Dendrocygna viduata, Porphyrio alleni, Porphyrio alleni, Egretta ardesiaca while it showed a regression of the favorable areas to Egretta alba. The estimated uses values showed that the ethno-zoological knowledge on the bird species differed according to the ethnic groups. Birds are used for food, medicinal and magico-mystics purposes. The magico-mystics and food were the most frequent used categories. Homogeneity of knowledge was found among the informants regarding the ethnic group as well as for the sex with respectively 0.66 and 0.7 for the use diversity value (ID) and use equitability value (IE). No significant difference was found between the informant for the use diversity value (ID) and use equitability value (IE). This study helps to build a database on 6 birds’ species and can be used for bird game ranching and game farming in Benin. [less ▲]

Detailed reference viewed: 36 (1 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 219 (103 ULg)
Full Text
Peer Reviewed
See detailÉcologie et gestion des espèces multi-usages du genre Erythrophleum (Fabaceae-Caesalpinioideae) en Afrique (synthèse bibliographique)
Gorel, Anaïs ULg; Fayolle, Adeline; Doucet, Jean-Louis ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015), 19

Littérature. Erythrophleum ivorense, E. suaveolens, E. africanum et E. lasianthum diffèrent morphologiquement et sont présentes dans des aires climatiques distinctes. Elles sont héliophiles non pionnières ... [more ▼]

Littérature. Erythrophleum ivorense, E. suaveolens, E. africanum et E. lasianthum diffèrent morphologiquement et sont présentes dans des aires climatiques distinctes. Elles sont héliophiles non pionnières (E. ivorense et E. suaveolens) ou pionnières (E. africanum). La dispersion primaire est ballochore. Les graines présentent une période de dormance et peuvent rester plusieurs années dans le sol. La phénologie est régulière et annuelle. La croissance annuelle moyenne varie entre les espèces, de la plus élevée pour E. ivorense (0,65 cm par an) à la plus faible pour E. africanum (0,16 cm par an). Elles sont largement utilisées dans la médecine traditionnelle. Seules E. ivorense et E. suaveolens sont exploitées pour le bois d’oeuvre et soumises à des normes d’exploitation et des tests sylvicoles. Conclusions. Les données sur l’écologie des espèces du genre Erythrophleum sont globalement mieux renseignées pour E. ivorense et E. suaveolens en raison de leur importance économique. Cette synthèse a permis de mettre en évidence certains manques de connaissances notamment sur la phénologie (relation avec le climat, périodes de fructifications), les diamètres minimums de fructification et les mécanismes de levée de dormance naturelle des graines. Remédier à ces lacunes contribuerait notablement à améliorer les méthodes de gestion des populations de ces espèces. [less ▲]

Detailed reference viewed: 56 (9 ULg)