References of "Bogaert, Jan"
     in
Bookmark and Share    
Full Text
See detailInvestigation of edge effect on wood density in recent tropical forest edges in Yangambi Man and Biosphere Reserve
de Haulleville, Thalès ULg; Bogaert, Jan ULg; Beeckman, Hans

Conference (2013, April)

Rapid development of lumbering activities in tropical forested areas has an important impact on carbon stocks and landscape configuration. Indeed, lumbering tend to fragment forest patches, extend edges ... [more ▼]

Rapid development of lumbering activities in tropical forested areas has an important impact on carbon stocks and landscape configuration. Indeed, lumbering tend to fragment forest patches, extend edges length, and expose core areas to non-forested ecosystems. These exposed core areas then undergo new constraints that can lead to a shift in their ecological features, called the edge effect. We investigate the possible presence of an edge effect on wood density in Yangambi reserve. Wood density (along with diameter and height) is a key feature for biomass estimations in tropical forests. Thus, fluctuations of wood density in forest edges could lead to incorrect estimations of carbon stocks. Ten 1ha plots were installed in core and recent (5 to 10 years) forest¿s edges. Trees were measured and wood samples were collected for density analysis. We focused on 2 main research questions: 1) Does the edge effect induce the emergence of species with a higher or lower wood density in edge area? 2) Does wood density differ amongst individuals of the same specie in core and in edge area? While the data is still being explored as we write, preliminary results seem to indicate that there is no significant difference between the overall mean wood density in edge and core plots. Density differences amongst species are still under exploration. If this behaviour still holds, this would imply that the fragmentation of a forested landscape has no short-term effect on the overall forest wood density and thus, no effect on biomass estimations. [less ▲]

Detailed reference viewed: 29 (2 ULg)
Full Text
Peer Reviewed
See detailEffets de lisière sur la productivité du teck (Tectona grandis L.f.): étude de cas des teckeraies privées du Sud-Bénin
Toyi, Mireille Scholastique; Bastin, Jean-François ULg; Andre, Marie ULg et al

in Tropicultura (2013), 31(1), 62-70

The present study aims to improve the production of teak wood (Tectona grandis L.f.) in private plantations in southern Benin through the application of a central concept in landscape ecology: the edge ... [more ▼]

The present study aims to improve the production of teak wood (Tectona grandis L.f.) in private plantations in southern Benin through the application of a central concept in landscape ecology: the edge effect. As teak is an heliophilous species, the hypothesis of a higher wood production in edges was tested on the basis of the basal area. Sixty-two private teak plantations were investigated and 10,667 trees were measured. The stratified sampling scheme in three distinct parts for each plantation (the centre, the edge and the summits) permitted to highlight the edge effect on wood production. For each part, a plot was installed and the diameter at breast height (dbh) was measured for all trees. The leaf area between the edge and the centre of plantations was measured. Finally, the influence of the spatial configuration of plantations and the direction of each side of these plantations on the production of wood was tested. Results show that the edge effect on the production of teak wood affects four planting lines, the first presenting a production of 150% relative to the centre. We noticed a significant influence of the edge on the leaf area of about 218% relative to the centre. No influence of the direction of the sides of the plantation was observed. The shape of the plantations presents a significant influence on the wood production. These results permitted to propose a planting model included in an agroforestry system that optimizes the production of wood per area and having a succession of two planting lines interrupted by fields. [less ▲]

Detailed reference viewed: 24 (4 ULg)
Full Text
Peer Reviewed
See detailTree plantation will not compensate natural woody vegetation cover loss in the Atlantic department of Southern Benin
Toyi, Mireille Scholastique; Barima, Sabas; Mama, Adi et al

in Tropicultura (2013), 31(1),

This study deals with land use and land cover changes for a 33 years period. We assessed these changes for eight land cover classes in the south of Benin by using an integrated multi-temporal analysis ... [more ▼]

This study deals with land use and land cover changes for a 33 years period. We assessed these changes for eight land cover classes in the south of Benin by using an integrated multi-temporal analysis using three Landsat images (1972 Landsat MSS, 1986 Landsat TM and 2005 Landsat ETM+). Three scenarios for the future were simulated using a first-order Markovian model based on annual probability matrices. The contribution of tree plantations to compensate forest loss was assessed. The results show a strong loss of forest and savanna, mainly due to increased agricultural land. Natural woody vegetation (“forest”, “wooded savanna” and “tree and shrub savanna”) will seriously decrease by 2025 due to the expansion of agricultural activities and the increase of settlements. Tree plantations are expected to double by 2025, but they will not compensate for the loss of natural woody vegetation cover. Consequently, we assist to a continuing woody vegetation area decrease. Policies regarding reforestation and forest conservation must be initiated to reverse the currently projected tendencies. [less ▲]

Detailed reference viewed: 30 (7 ULg)
Full Text
Peer Reviewed
See detailLandscape Ecology: a unifying discipline
Bogaert, Jan ULg; Andre, Marie ULg

in Tropicultura (2013), 31(1), 1-2

Detailed reference viewed: 26 (3 ULg)
Full Text
See detailAnalyse des facteurs anthropiques de dégradation des bois de tapia (Uapaca bojeri) d'Arivonimamo
Rakotondrasoa, Olivia Lovanirina; Ayral, Astrid; Stein, Julien et al

in Verheggen, François; Bogaert, Jan; Haubruge, Eric (Eds.) Les vers à soie malgaches : Enjeux écologiques et socio-économiques (2013)

The tapia woodland, an endemic ecosystem of Madagascar, plays an important role in the household economy of the local communities. The dependence of local people on the tapia woodland has led to the ... [more ▼]

The tapia woodland, an endemic ecosystem of Madagascar, plays an important role in the household economy of the local communities. The dependence of local people on the tapia woodland has led to the disturbance and degradation of this ecosystem. In this context, the current study aimed to identify and analyze the anthropogenic factors leading to the degradation of the tapia woodland in Arivonimamo. The working hypothesis was that fire constitutes today the main disturbance factor of the tapia woodland in Arivonimamo, leading to the deforestation and to a continuous degradation of this ecosystem. A typology of indicators of vegetation disturbance was established based upon literature; it was followed by an inventory of these indicators along four transects situated orthogonally around the six villages of the study site. This study showed that fire is no longer the main cause of deforestation and degradation of tapia woodlands in Arivonimamo. The continuing degradation of the woodland is mainly caused by illegal logging by the local population. These results provide key information to improve the management of the tapia woodlands in Arivonimamo. [less ▲]

Detailed reference viewed: 20 (2 ULg)
Full Text
See detailActivité journalière et comportement d’alimentation de Borocera cajani Vinson 1863 (Lepidoptera: Lasiocampidae) sur deux de ses plantes hôtes : Uapaca bojeri Baillon 1874 et Aphloia theiformis (Vahl) Bennett 1840
Razafimanantsoa, Tsiresy; Raminosoa, Noromalala; Rakotondrasoa, Olivia et al

in Verheggen, François; Bogaert, Jan; Haubruge, Eric (Eds.) Les vers à soie malgaches : Enjeux écologiques et socio-économiques (2013)

Borocera cajani or landibe is a wild silk-moth, which silk is the most widely used in the textile industry in Madagascar. This endemic species is found throughout the island, but colonizes especially the ... [more ▼]

Borocera cajani or landibe is a wild silk-moth, which silk is the most widely used in the textile industry in Madagascar. This endemic species is found throughout the island, but colonizes especially the tapia forest in the central Highlands. The species has an important economic, culinary and cultural role in the Island. It is polyphagous and frequents several host plants. The daily activity of the larvae of B. cajani has been studied in their natural habitat on two native host plants of the tapia forest: Uapaca bojeri and Aphloia theiformis. Continuous observations during 24 hours on 54 individuals of the last instar of B. cajani have been conducted. Daily periods of activity were found to vary according to the host plant species. Larvae feeding on U. bojeri allocate 6.9% of their time to feed, while the larvae feeding on A. theiformis spend 3.3% of their time. Only 1.0% (15 minutes) and 0.7% (10 minutes) of the observed periods were allocated to movement, in the larvae feeding on U. bojeri et A. theiformis, respectively. Larvae observed on A. theiformis took an average of 3.1 ± 0.2 meals a day, which lasted 15,4 ± 1,3 min. Larvae observed on U. bojeri took an average of 1.9 ± 0.1 meals a day, which lasted 54.8 ± 5.2 min. [less ▲]

Detailed reference viewed: 14 (0 ULg)
Full Text
Peer Reviewed
See detailImportance de la méthode de coupe sur la régénération de Combretaceae du Bassin arachidier sénégalais
Faye, E; Diallo, H; Samba, SAN et al

in Tropicultura (2013), 31(1), 44-52

Detailed reference viewed: 16 (0 ULg)
Full Text
Peer Reviewed
See detailThe spatial footprint of the non-ferrous metal industry in Lubumbashi
Vranken, Isabelle ULg; Munyemba Kankumbi, François; Amisi Mwana, Yamba et al

in Tropicultura (2013), 31(1), 20-27

In the south-eastern part of the Katanga Province (Democratic Republic of the Congo), high concentrations of copper and cobalt are found in the soils of the well-known “Copper Belt”. Due to the dominant ... [more ▼]

In the south-eastern part of the Katanga Province (Democratic Republic of the Congo), high concentrations of copper and cobalt are found in the soils of the well-known “Copper Belt”. Due to the dominant south-eastern winds, the metallurgic industry in Lubumbashi has been the source of spatially concentrated atmospheric deposits of non-ferrous metal particles and associated substances in a cone-shaped zone, situated north-west of the metal processing site. The existence of this zone has been evidenced using two different techniques: firstly, by means of landscape metric comparisons of the vegetation and bare soil patterns in two study areas, one inside the pollution cone and one outside; secondly, by means of the theory on city perception developed by Kevin Lynch. Higher fragmentation and lower vegetation presence were observed inside the pollution cone, reflecting the negative impact of atmospheric deposits. Those differences were higher for sites closer to the emission source. Lynch’s approach outlined the negative impact of diverse industrial plants on the perception by the local population. Six pollution districts and several contaminated paths, limits, nodes and polluting landmarks were identified. Citizens even recognize them as part of the collective image of the city. [less ▲]

Detailed reference viewed: 103 (21 ULg)
Full Text
Peer Reviewed
See detailIdentification des indicateurs de dégradation de la forêt de tapia (Uapaca bojeri) par une analyse sylvicole
Rakotondrasoa, OL; Malaisse, François ULg; Rajoelison, G et al

in Tropicultura (2013), 31(1), 10-19

Detailed reference viewed: 23 (3 ULg)
Full Text
Peer Reviewed
See detailAnthropisation et dynamique des paysages en zone soudanienne au nord du Bénin
Mama, A; Sinsin, B; De Cannière, C et al

in Tropicultura (2013), 31(1), 78-88

Detailed reference viewed: 29 (6 ULg)
Full Text
Peer Reviewed
See detailDynamics in mangroves assessed by high-resolution and multi-temporal satellite data: a case study in Zhanjiang Mangrove National Nature Reserve (ZMNNR), P. R. China
Leempoel, K; Satyaranayana, B; Bourgeois, C et al

in Biogeosciences Discussions (2013), 10

Detailed reference viewed: 23 (3 ULg)
Full Text
Peer Reviewed
See detailSpecies persistence in landscapes with spatial variation in habitat quality: a pair approximation model
Liao, J; Li, ZQ; Hiebeler, DE et al

in Journal of Theoretical Biology (2013), 335

Detailed reference viewed: 23 (1 ULg)
Full Text
See detailPertinence de la mise en oeuvre des initiatives de Réductions des Emissions dues à la Déforestation et à la Dégradation des forêts (REDD) pour les communautés locales. Cas des formations de tapia dans la région d'Itasy
Ratsimba, HR; Rabemananjara, ZH; Rabefarihy, AT et al

in Verheggen, François; Bogaert, Jan; Haubruge, Eric (Eds.) Les vers à soie malgaches: Enjeux écologiques et socio-économiques (2013)

Detailed reference viewed: 22 (2 ULg)
Full Text
Peer Reviewed
See detailImpact de l'anthropisation sur les variables microclimatiques dans un écosystème forestier des environs de Kisangani (Réserve de Masako, R.D. Congo)
Iyongo Waya Mongo, L; Bulamuzi Bilha, J; Iyongo Bompetsa, C et al

in Annales des Instituts Supérieurs d’Etudes Agronomiques de Bengamisa (2013), 5

Detailed reference viewed: 16 (1 ULg)
Full Text
Peer Reviewed
See detailEffets de lisière sur la teneur en eau et la température du sol à l'échelle du jardin systématique de l'INERA/Yangambi en R.D. Congo
Alongo Longomba, S; Visser, M; Kombele Bishosha, F et al

in Annales des Instituts Supérieurs d’Etudes Agronomiques de Bengamisa (2013), 5

Detailed reference viewed: 14 (1 ULg)
Full Text
Peer Reviewed
See detailPropriétés et diagnostic de l'état agropédologique du sol de la série Yakonde après fragmentation de la forêt à Yangambi, R.D. Congo
Alongo Longomba, S; Visser, M; Kombele Bishosha, F et al

in Annales des Instituts Supérieurs d’Etudes Agronomiques de Bengamisa (2013), 5

Detailed reference viewed: 13 (1 ULg)
Full Text
Peer Reviewed
See detailStructure spatiale des trois espèces les plus abondantes dans la Réserve Forestière de la Yoko, Ubundu, République Démocratique du Congo
Kumba, S; Nshimba, H; Ndjele, L et al

in Tropicultura (2013), 31(1), 53-61

Detailed reference viewed: 18 (3 ULg)
Full Text
Peer Reviewed
See detailDiversité et distribution d'abondances des plantes d'un écosystème protégé dans un paysage anthropisé: cas de la Réserve Naturelle Forestière de Bururi, Burundi
Havyarimana, F; Bigendako, MJ; Masharabu, T et al

in Tropicultura (2013), 31(1), 28-35

Detailed reference viewed: 13 (1 ULg)
Full Text
Peer Reviewed
See detailEffets de lisière et sex-ratio de rongeurs forestiers dans un écosystème fragmenté en République Démocratique du Congo (Réserve de Masako, Kisangani)
Iyongo Waya Mongo, L; De Cannière, C; Ulyel, J et al

in Tropicultura (2013), 31(1), 3-9

Detailed reference viewed: 14 (1 ULg)
Full Text
Peer Reviewed
See detailEffets de la fragmentation des forêts par l'agriculture itinérante sur la dégradation de quelques propriétés physiques d'un ferralso échantillonné à Yangambi, R.D. Congo
Alongo, Sylvain; Visser, Marjolein; Drouet, Thomas et al

in Tropicultura (2013), 31(1), 36-43

The knowledge of changes occurring in the soil cover at the forest edge is needed to better understand the impact of forest fragmentation on soil parameters. The objective of this study is to evaluate the ... [more ▼]

The knowledge of changes occurring in the soil cover at the forest edge is needed to better understand the impact of forest fragmentation on soil parameters. The objective of this study is to evaluate the effects of forest fragmentation caused by shifting agriculture on texture, bulk density, total porosity and soil hydraulic conductivity in the layers at 0-10, 10-20 and 20-30 cm depth by the transect method in a perspective of sustainable land management in the region of Yangambi. The results obtained show that the edge between the fallow grassland and dense forest has a width of 70 m. Degradation of all the physical properties of soils relative to the dense forest is very significant (p<0.01) for the studied layers. Fragmentation of forests by shifting cultivation increases the phenomenon of selective loss of clays of the surface soil layers and consequently increases its bulk density and decreases the permeability and porosity with depth under the fallow grass and edge. The texture data associated with textural classes in the FAO textural triangle indicate a change in texture of the soil under different land uses for the tree layers studied. [less ▲]

Detailed reference viewed: 25 (3 ULg)