Afrormosia; Assamela; Central Africa; tropical rain forest; autecology; forest history; shifting cultivation; past human disturbances; charcoal
Résumé :
[en] While most past studies have emphasized the relationships between specific forest stands and edaphic factors, recent observations in Central African moist forests suggested that an increase of slash-and-burn agriculture since 3000–2000 BP (Before Present) could be the main driver of the persistence of light-demanding tree species. In order to examine anthropogenic factors in the persistence of such populations, our study focused on Pericopsis elata, an endangered clustered timber species. We used a multidisciplinary approach comprised of botanical, anthracological and archaeobotanical investigations to compare P. elata patches with surrounding stands of mixed forest vegetation (“out-zones”). Charcoal samples were found in both zones, but were significantly more abundant in the soils of patches. Eleven groups of taxa were identified from the charcoals, most of them also present in the current vegetation. Potsherds were detected only inside P. elata patches and at different soil depths, suggesting a long human presence from at least 2150 to 195 BP, as revealed by our charcoal radiocarbon dating. We conclude that current P. elata patches most likely result from shifting cultivation that occurred ca. two centuries ago. The implications of our findings for the dynamics and management of light-demanding tree species are discussed.
Disciplines :
Biologie végétale (sciences végétales, sylviculture, mycologie...) Archéologie Sciences du vivant: Multidisciplinaire, généralités & autres Sciences de l’environnement & écologie Arts & sciences humaines: Multidisciplinaire, généralités & autres
Auteur, co-auteur :
Bourland, Nils; Musée royal de l'Afrique centrale > Biologie du bois
Cerisier, François
Daïnou, Kasso ; Université de Liège > Ingénierie des biosystèmes (Biose) > Laboratoire de Foresterie des régions trop. et subtropicales
Livingstone Smith, Alexandre; Musée royal de l'Afrique centrale > Préhistoire et archéologie
Hubau, Wannes; Musée royal de l'Afrique centrale > Biologie du bois
Beeckman, Hans; Musée royal de l'Afrique centrale > Biologie du bois
Brostaux, Yves ; Université de Liège > Agronomie, Bio-ingénierie et Chimie (AgroBioChem) > Statistique, Inform. et Mathém. appliquée à la bioingénierie
Fayolle, Adeline ; Université de Liège > Ingénierie des biosystèmes (Biose) > Gestion des ressources forestières et des milieux naturels
Biwolé, Achille; Université de Liège - ULiège > BIOSE > Gestion des Ressources Forestières
Feteke, Fousseni ; Université de Liège > Forêts, Nature et Paysage > Gestion des ressources forestières et des milieux naturels
Gillet, Jean-François
Morin-Rivat, Julie ; Université de Liège > Ingénierie des biosystèmes (Biose) > Laboratoire de Foresterie des régions trop. et subtropicales
Lejeune, Philippe ; Université de Liège > Ingénierie des biosystèmes (Biose) > Gestion des ressources forestières et des milieux naturels
Ntoundé Tiba, Eric
Van Acker, Joris; Universiteit Gent - Ugent
Doucet, Jean-Louis ; Université de Liège > Ingénierie des biosystèmes (Biose) > Laboratoire de Foresterie des régions trop. et subtropicales
Maley, J.; Brenac, P. Vegetation dynamics, palaeoenvironments and climatic changes in the forests of western Cameroon during the last 28,000 years BP. Rev. Palaeobot. Palynol. 1998, 99, 157-187.
Nguetsop, V.F.; Servant-Vildary, S.; Servant, M. Late Holocene climatic changes in West Africa, a high resolution diatom record from equatorial Cameroon. Quat. Sci. Rev. 2004, 23, 591-609.
Clist, B. Traces de très anciennes occupations humaines de la forêt tropicale au Gabon. In Central African Hunter-Gatherers in a Multidisciplinary Perspective: Challenging Elusiveness; Biesbrouck, K., Elders, S., Rossel, G., Eds.; Research School for Asian, African and Amerindian Studies: Leiden, The Netherlands, 1999; pp. 75-87.
Van Gemerden, B.S.; Olff, H.; Parren, M.P.E.; Bongers, F. The pristine rain forest? Remnants of historical human impacts on current tree species composition and diversity. J. Biogeogr. 2003, 30, 1381-1390.
Brncic, T.M.; Willis, K.J.; Harris, D.J.; Washington, R. Culture or climate? The relative influences of past processes on the composition of the lowland Congo rainforest. Philos. Trans. R. Soc. Lond. Ser. B 2007, 36, 229-242.
Verdu, P.; Austerlitz, F.; Estoup, A.; Vitalis, R.; Georges, M.; Théry, S.; Froment, A.; Le Bomin, S.; Gessain, A.; Hombert, J.M.; et al. Origins and genetic diversity of Pygmy hunter-gatherers from Western Central Africa. Curr. Biol. 2009, 19, 312-318.
Ngomanda, A.; Jolly, D.; Bentaleb, I.; Chepstow-Lusty, A.; Makaya, M.; Maley, J.; Fontugne, M.; Oslisly, R.; Rabenkogo, N. Lowland rainforest response to hydrological changes during the last 1500 years in Gabon, Western Equatorial Africa. Quat. Res. 2007, 67, 411-425.
Ngomanda, A.; Neumann, K.; Schweizer, A.; Maley, J. Seasonality change and the third millennium BP rainforest crisis in southern Cameroon (Central Africa). Quat. Res. 2009, 71, 307-318.
Neumann, K.; Bostoen, K.; Höhn, A.; Kahlheber, S.; Ngomanda, A.; Tchiengué, B. First farmers in the Central African rainforest: A view from southern Cameroon. Quat. Int. 2012, 249, 53-62.
De Wasseige, C.; de Marcken, P.; Bayol, N.; Hiol Hiol, F.; Mayaux, P.; Desclée, B.; Nasi, R.; Billand, A.; Defourny, P.; Eba'a, R. Les Forêts du Bassin du Congo-Etat des Forêts 2010; Office des Publications de l'Union Européenne: Luxembourg, Luxembourg, 2012.
Réjou-Méchain, M.; Flores, O.; Bourland, N.; Doucet, J.-L.; Fétéké, R.; Pasquier, A.; Hardy, O.J. Spatial aggregation of tropical trees at multiple spatial scales. J. Ecol. 2011, 99, 1373-1381.
Fétéké, F.; Philippart, J. Plan D'aménagement des Unités Forestières D'aménagement no 10030 et 10031 Regroupées; Cellule d'aménagement Pallisco and Nature Plus: Mindourou, Cameroon and Gembloux, Belgium, 2008.
Clist, B. Gabon: 100,000 ans d'Histoire; Centre Culturel français Saint Exupéry/Ministère de la Coopération/Sépia: Libreville, Gabon, 1995.
Schwartz, D.; Lanfranchi, R. Les cadres paléoenvironnementaux de l'évolution humaine en Afrique Centrale Atlantique. LAnthropologie 1993, 97, 17-50.
Horn, S.P.; Sanford, R.L. Holocene fires in Costa Rica. Biotropica 1992, 24, 354-361.
Tutin, C.E.; White, L.J.; Mackanga-Missandzou, A. Lightning strike burns large forest tree in the Lope Reserve, Gabon. Glob. Ecol. Biogeogr. Lett. 1996, 5, 36-41.
Cochrane, M.A.; Ryan, K.C. Tropical fire ecology. In Climate Change, Land Use, and Ecosystem Dynamics; Cochrane, M.A., Ed.; Praxis Publishing Ltd.: Chichester, UK, 2009; pp. 25-62.
White, L.J.T.; Oates, J. New data on the history of the plateau forest of Okomu, southern Nigeria: An insight into how human disturbance has shaped the African rain forest. Glob. Geogr. Biogeogr. 1999, 8, 355-361.
Cerutti, P.O.; Nasi, R.; Tacconi, L. Sustainable forest management in Cameroon needs more than approved forest management plans. Ecol. Soc. 2008, 13, 36.
Sist, P.; Ferreira, F.N. Sustainability of reduced-impact logging in the Eastern Amazon. For. Ecol. Manag. 2007, 243, 199-209.
Ouédraogo, D.-Y.; Fayolle, A.; Daïnou, K.; Demaret, C.; Bourland, N.; Lagoute, P.; Doucet, J.-L. Enrichment of logging gaps with a high conservation value species (Pericopsis elata) in a central African moist forest. Forests 2014, 5, 3031-3047.
Bourland, N.; Kouadio, Y.L.; Colinet, G.; Doucet, J.-L. Pericopsis elata (Harms) Meeuwen in the south-eastern part of Cameroon: Ecological and pedological approaches to improve the management of an endangered commercial timber species. Int. For. Rev. 2010, 12, 111.
Swaine, M.D. Rainfall and soil fertility as factors limiting forest species distributions in Ghana. J. Ecol. 1996, 84, 419-428.
Ampofo, S.T.; Lawson, G.W. Growth of seedlings of Afrormosia elata Harms in relation to light intensity. J. Appl. Ecol. 1972, 9, 301-306.
Kyereh, B.; Swaine, M.D.; Thompson, J. Effect of light on the germination of forest trees in Ghana. J. Ecol. 1999, 87, 772-783.
Bourland, N.; Kouadio, Y.L.; Lejeune, P.; Sonké, B.; Philippart, J.; Daïnou, K.; Fétéké, F.; Doucet, J.-L. Ecology of Pericopsis elata (Fabaceae), an endangered timber species in south-eastern Cameroon. Biotropica 2012, 44, 840-847.
Kouadio, Y.L.; Doucet, J.-L. Etude du comportement de Baillonella toxisperma Pierre (moabi) dans les trouées d'abattage enrichies. Biotechnol. Agron. Soc. Environ. 2009, 13, 317-324.
White, F. The Vegetation of Africa; UNESCO: Paris, France, 1983.
Grubb, P. Refuges and dispersal in the speciation of African forest mammals. In Biological Diversification in the Tropics; Prance, G.T., Ed.; Columbia University Press: New York, NY, USA, 1982; pp. 537-553.
Chapman, C.A. Speciation of tropical rainforest primates of Africa: Insular biogeography. Afr. J. Ecol. 1983, 21, 297-308.
Forbes, M.S.; Raison, R.J.; Skjemstad, J.O. Formation, transformation and transport of black carbon (charcoal) in terrestrial and aquatic ecosystems. Sci. Total Environ. 2006, 370, 190-206.
Brncic, T.M. Ecology and Patch Dynamics of Megaphrynium Macrostachyum (Benth.) Milne-Redh. (Marantaceae) in the South-West Central African Republic. Ph.D. Thesis, Oxford University, Oxford, UK, June 2002.
Hubau, W.; Van Den Bulcke, J.; Kitin, P.; Mees, F.; Van Acker, J.; Beeckman, H. Charcoal identification in species-rich biomes: A protocol for Central Africa optimised for the Mayumbe forest. Rev. Palaeobot. Palynol. 2012, 171, 164-178.
Chronometric Dating in Archaeology; Taylor, R.E., Aitken, M., Eds.; Advances in Archaeological and Museum Science; Springer-Verlag New York Inc.: New York, NY, USA, 1997; Volume 2.
Wolda, H. Similarity indices, sample size and diversity. Oecologia 1981, 50, 296-302.
Biodiv R, Version 1.2; A program to compute statistically unbiased indices of species diversity within sample and species similarity between samples using rarefaction principles; Evolutionary Biology & Ecology: Brussels, Belgium, 2010. Available online: http://ebe.ulb.ac.be/ebe/Software. html (accessed on 13 October 2014).
Cottam, G.; Curtis, J.T. The use of distance measures in phytosociological sampling. Ecology 1956, 37, 451-460.
Hall, J.B.; Bada, S.O. The distribution and ecology of Obeche (Triplochiton scleroxylon). J. Ecol. 1979, 67, 543-564.
Boyemba, F. Écologie de Pericopsis Elata (Harms) Van Meeuwen (Fabaceae), Arbre de Forêt Tropicale Africaine à Répartition Agrégée. Ph.D. Thesis, Université Libre de Bruxelles, Université de Kisangani, Brussels, Belgium, August 2011.
Nyemeck Binam, J.; Tonye, J.; Wandji, N.; Nyambi, G.; Akoa, M. Factors affecting the technical efficiency among smallholder farmers in the slash and burn agriculture zone of Cameroon. Food Policy 2004, 29, 531-545.
Clist, B. The Okala site, Estuaire province, Gabon. Its importance for understanding the transition to sedentarization in central Africa. Comptes Rendus l'Académie Sci. Ser. IIA Earth Planet. Sci. 1997, 325, 151-156.
Oslisly, R.; White, L.J.T. La Relation Home/Milieu dans la Réserve de la Lopé (Gabon) au Cours de L'Holocène: Les Implications sur L'environnement. Dynamique à Long Terme des écosystèmes Forestiers Intertropicaux; ORSTOM: Paris, France, 1996.
Hart, T.B.; Hart, J.A.; Dechamps, R.; Fournier, M.; Ataholo, M. Changes in forest composition over the last 4000 years in the Ituri basin, Zaïre. In The Biodiversity of African Plants; Van der Maesen, L.J.G., Van der Burgt, X.M., Van Medenbach de Rooy, J.M., Eds.; Springer-Verlag: Heidelberg, Germany, 1996; pp. 545-563.
Meister, C.; Eggert, M. On the early iron age in southern Cameroun: The site of Akonétye. J. Afr. Archaeol. 2008, 6, 183-202.
Oslisly, R.; Bentaleb, I.; Favier, C.; Fontugne, M.; Gillet, J.-F.; Morin-Rivat, J. West Central African peoples: Survey of radiocarbon dates over the past 5000 years. Radiocarbon 2013, 55, 1377-1382.
Newbery, D.M.; Van Der Burgt, X.M.; Worbes, M.; Chuyong, G.B. Transient dominance in a central African rain forest. Ecol. Monogr. 2013, 83, 339-382.
Livingstone Smith, A. Histoire du décor à la roulette en Afrique subsaharienne. J. Afr. Archaeol. 2007, 5, 189-216.
CTFT. Fiche botanique, forestière, industrielle et commerciale: Assamela. Bois For. Trop. 1956, 50, 17-20.
Dupuy, B. Bases Pour une Sylviculture en Forêt Dense Tropicale Humide Africaine. Série FORAFRI, Doc. 4; CIRAD-Forêt: Montpellier, France, 1998.
Chao, A. Species richness estimation. In Encyclopedia of Statistical Sciences; Balakrishnan, N., Read, C.B., Vidakovic, B., Eds.; Wiley: Hoboken, NJ, USA, 2005; pp. 7909-7916.
Vleminckx, J.; Morin-Rivat, J.; Biwolé, A.B.; Daïnou, K.; Gillet, J.-F.; Doucet, J.-L.; Drouet, T.; Hardy, O.J. Soil charcoal to assess the impacts of past human disturbances on tropical forests. PLoS One 2014, 9, e108121.
Balee, W. Cultural Forests of the Amazon: A Historical Ecology of People and Their Landscapes; University of Alabama Press: Tuscaloosa, AL, USA, 2013.
Hunt, C.O.; Rabett, R.J. Holocene landscape intervention and plant food production strategies in island and mainland Southeast Asia. J. Archaeol. Sci. 2014, 51, 22-33.
McFadgen, B.G. Dating New Zealand archaeology by radiocarbon. N. Z. J. Sci. 1982, 25, 379-392.
Gavin, D.G. Estimation of inbuilt age in radiocarbon ages of soil charcoal for fire history studies. Radiocarbon 2001, 43, 27-44.
Tans, P.P.; de Jong, A.F.M.; Mook, W.G. Natural atmospheric 14C variation and the Suess effect. Nature 1979, 280, 826-828.
Fichtler, E.; Clark, D.A.; Worbes, M. Age and long-term growth of trees in an old-growth tropical rain forest, based on analyses of tree rings and 14C. Biotropica 2003, 35, 306-317.
Stuiver, M.; Becker, B. High-precision decadal calibration of the radiocarbon time scale, AD 1950-6000 BC. Radiocarbon 1993, 35, 35-65.
Petchey, F.; Anderson, A.; Hogg, A.; Zondervan, A. The marine reservoir effect in the Southern Ocean: An evaluation of extant and new R values and their application to archaeological chronologies. J. R. Soc. N. Z. 2008, 38, 243-262.
De Ridder, M.; Toirambe, B.; van den Bulcke, J.; Bourland, N.; van Acker, J.; Beeckman, H. Dendrochronological potential in a semi-deciduous rainforest: The case of Pericopsis elata in central Africa. Forests 2014, 5, 3087-3106.
Gérard, P. Etude écologique de la Forêt Dense à Gilbertiodendron Dewevrei dans la Région de l'Uele, Publications de l'Institut National pour l'Etude Agronomique du Congo: Yangambi, Belgian Congo, 1960; Volume 87, pp. 1-159.
Hart, T.B.; Hart, J.A.; Murphy, P.G. Monodominant and species-rich forests of the humid tropics: Causes for their co-occurrence. Am. Nat. 1989, 133, 613-633.
Germain, R.; Evrard, C. Etude écologique et Phytosociologique de la Forêt à Brachystegia Laurentii; Publications de l'Institut National pour l'Etude Agronomique du Congo Belge, INEAC: Yangambi, Belgian Congo, 1956.
Biwolé, A.B.; Morin-Rivat, J.; Fayolle, A.; Bitondo, D.; Dedry, L.; Daïnou, K.; Hardy, O.J.; Doucet, J.-L. New data on the recent history of the littoral forests of southern Cameroon: An insight into the role of historical human disturbances on the current forest composition. Plant Ecol. Evol. 2015, doi:10.5091/plecevo.2015.1011.
Karsenty, A.; Gourlet-Fleury, S. Assessing sustainability of logging practices in the Congo Basin's managed forests: The issue of commercial species recovery. Ecol. Soc. 2006, 11, 26.
Doucet, J.-L.; Ntchandi Otimbo, P.A.; Boubady, A.-G. Comment assister la régénération naturelle de l'okoumé dans les concessions forestières? Bois For. Trop. 2004, 279, 59-72.
