ORBi Open Repository and Bibliography
In may 2007, the ULg's Administrative Board (joined in June 2007 by the FUSAGx) decided to create an institutional repository and defined a strong institutional self-archiving policy to increase the visibility, accessibility and impact of the University's publications (Board's decision).
This decision led to the official launch, in November 2008, of the ORBi platform including both the Academic Bibliography and the Institutional Repository of the Wallonia-Europe University Academy.
Did the savannah « flourished » 3000 years ago in the so-called Sangha River Interval of the Guineo-Congolian rainforest ? A retrospective study using stable isotopes and phytoliths - Bentaleb, Ilham; Freycon, Vincent; Gillet, Jean-François; Oslisly, Richard; Bremond, Laurent; Favier, Charly; Fontugne, Michel; Droissart, Vincent; Gourlet-Fleury, Sylvie; Guillou, Gaël; Martin, Céline; Morin, Julie; Ngomanda, Alfred; de Saulieu, Geoffroy; Sebag, David; Subitani, Sandrine; Wonkam, Christelle; Ngeutchoua, Gabriel
We aim to improve our knowledge of the dynamic of the vegetation in Central Africa during the last 5 kyrs and to discuss the main hypothesis described in the literature - humans versus climatic impacts- both suggested as responsible of the Congo basin rainforest decline observed between 3 and 2.5 kyrs. We use the carbon isotopic composition of well-dated Central African soils to reconstruct the dynamic of the vegetation cover. We will discuss the carbon isotopic composition of the soil organic carbon methodology for reconstructing palaeovegetation in the light of Rayleigh distillation model. We showed that numerous sites exhibit a...
Nineteenth century human history explains the dominance of light-demanding tree species in Central African moist forests - Morin, Julie; Fayolle, Adeline; Favier, Charly; Bremond, Laurent; Gourlet-Fleury, Sylvie; Lejeune, Philippe; Beeckman, Hans; Doucet, Jean-Louis
The canopy of central African moist forests is dominated by light-demanding trees. Most of these species show a distribution of diameters that indicates a regeneration shortage. Here we show through the combined analysis of botanical, palaeoecological, archaeological and historical data that most of these trees are not older than ca. 180 years. This age corresponds to the early 19th century (around 1830) when the slave-raiding, the interethnic wars and the colonization of the inlands by the Europeans disturbed the human spatial occupancy. After 1885, the spatial clumping of people and villages along the main communication axes induced less itinerancy in...
Identification of charred botanical remains provides more accurate information on past history in Central Africa - Morin, Julie; Biwolé, Achille; Bourland, Nils; Bremond, Laurent; Fayolle, Adeline; Gillet, Jean-François; Gorel, Anaïs; Gourlet-Fleury, Sylvie; Hardy, Olivier; Livingstone Smith, Alexandre; Oslisly, Richard; Vleminckx, Jason; Doucet, Jean-Louis; Beeckman, Hans
In palaeoenvironmental studies, charred botanical remains have rarely been identified to the species level before being sent to radiocarbon dating. Moreover, the age of most tropical spp. and thereby the age of the carbon sequestered during plant growth is not known. Dating unidentified charred wood in the tropics should be thus treated with caution because the accuracy of the dates is not guaranteed. Here we present 71 dates obtained on charred endocarps and wood charcoals sampled in soil pits in Cameroon and in the Rep. of the Congo. We taxonomically identified 43 samples then selected both identified and unidentified individual...
Wood anatomical characteristics of 600 African tropical species in relationship with their ecology - Morin, Julie; Fayolle, Adeline; Doucet, Jean-Louis; Beeckman, Hans
The tropical moist forest is a biome with a high number of species that are functionally different. The question arises whether there are patterns in the spectra of wood anatomical features according to functional types. Here we propose to present the main anatomical characteristics of 600 tropical species from the Guineo-Congolian domain in relationship with their ecology. We cross-checked two databases: the anatomical database InsideWood and the CoForTraits database of functional traits produced during the CoForChange project. After characterizing the main trends of the dataset, we performed multivariate analyses between the wood traits (i.e. the anatomical features) and six groups...
Late-Holocene moist forests of Central Africa: contribution of charcoal analysis - Morin, Julie; Bremond, Laurent; Gillet, Jean-François; Doucet, Jean-Louis; Beeckman, Hans
Wood charcoals are often uncovered in the soils of the tropical regions. They remain little studied, however, and this observation is even truer for charcoals coming from the dense humid forests of Central Africa. Here we aim at showing the interest of the analysis of soil charcoals in this region so as to understand the dynamics of past forest environments during the late-Holocene. Several examples of taxonomical identifications conducted on charcoals sampled in soil pits in Cameroon and in the Republic of the Congo are presented along with radiocarbon dates. These charcoals were hand-split then observed under an incident light...
Analyse à haute résolution spatiale et temporelle des activités humaines à l’Holocène récent dans les forêts humides d’Afrique Centrale - Morin, Julie; Gorel, Anaïs; Biwolé, Achille; Gillet, Jean-François; Bourland, Nils; Fayolle, Adeline; Daïnou, Kasso; Vleminckx, Jason; Hardy, Olivier J; Beeckman, Hans; Doucet, Jean-Louis
Des études paléoécologiques et archéologiques ont démontré que les populations humaines ont de longue date investi les forêts humides d’Afrique Centrale. Les occupations humaines ont toutefois été peu documentées en raison de difficultés relatives à l’accès au terrain. Nous présentons ici une méthodologie systématique basée sur la quantification et la datation des macrorestes botaniques carbonisés pour définir les activités humaines passées en forêt tropicale africaine. Pour cela, 53 sondages équidistants ont été creusés dans 3 sites du sud-est-du Cameroun. Dans chaque sondage ont été prélevées des quantités fixes de sol par couche de 10 cm. Les macrorestes botaniques carbonisés ont...
Knowing the past to anticipate the future: soil charcoal as a proxy to model forest evolution - Morin, Julie; Biwolé, Achille; Bourland, Nils; Daïnou, Kasso; Fayolle, Adeline; Gillet, Jean-François; Gorel, Anaïs; Hardy, Olivier J; Vleminckx, Jason; Doucet, Jean-Louis; Beeckman, Hans
Tropical forests of Central Africa constitute the second most important block of moist forest of the world. However little is known about their past evolution. Indeed, determining the past specific composition of these forests could allow modeling their evolution over time and providing data about their resilience capacity facing global change. To do this, we performed a pedoanthracological analysis in the semi-deciduous forests of southeastern Cameroon. We excavated test pits in 53 plots of botanical inventory along a gradient of vegetation, quantified wood charcoals by layers of 10 cm, identify the species present in charcoals, dated the charcoals by the...
Late-Holocene tropical moist-forests of southeastern Cameroon: some insight from soil charcoal analysis - Morin, Julie; Biwolé, Achille; Bourland, Nils; Daïnou, Kasso; Fayolle, Adeline; Gillet, Jean-François; Gorel, Anaïs; Hardy, Olivier; Vleminckx, Jason; Doucet, Jean-Louis; Beeckman, Hans
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 evolution over time and providing data about their resilience capacity facing global change. We performed a pedoanthracological analysis in the semi-deciduous forests of southeastern Cameroon. We excavated 53 test pits of 53 50 × 50 × 60 cm in plots of botanical inventory along a NS 80-km long...
High spatial resolution of late-Holocene human activities in the moist forests of Central Africa using soil charcoal and charred botanical remains - Morin, Julie; Biwolé, Achille; Gorel, Anaïs; Dedry, Laurent; Gillet, Jean-François; Bourland, Nils; Fayolle, Adeline; Daïnou, Kasso; Vleminckx, Jason; Hardy, Olivier; Livingstone Smith, Alexandre; Doucet, Jean-Louis; Beeckman, Hans
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 systematic quantitative and qualitative methodology based on soil charcoal and charred botanical remains. A total of 88 equidistant test-pits were excavated along six transects in two contrasting forest types in southern Cameroon. Charred botanical remains were collected by water-sieving and sorted by type (wood charcoals, oil palm endocarps, and unidentified seeds)....
The last 1,000 years in the Northern Congo Basin - Morin, Julie; Fayolle, Adeline; Favier, Charly; Bremond, Laurent; Gourlet-Fleury, Sylvie; Bayol, Nicolas; Lejeune, Philippe; Beeckman, Hans; Doucet, Jean-Louis
Review of the events that happened in the northern Congo basin during the last 1,000 yr. Positive impact of human disturbances on the regeneration of light-demanding trees. Negative impact of the European colonization and following events on human populations and tree regeneration.