Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-26T03:24:06.393Z Has data issue: false hasContentIssue false
  • English
  • Français

Seasonality change and the third millennium BP rainforest crisis in southern Cameroon (Central Africa)

Published online by Cambridge University Press:  20 January 2017

Alfred Ngomanda ,
Katharina Neumann ,
Astrid Schweizer  and
Jean Maley
Alfred Ngomanda*
Affiliation:
J.W. Goethe-Universität, Institut für Archäologische Wissenschaften, Abteilung Vor- und Frühgeschichte, Grüneburgplatz 1, D-60323 Frankfurt am Main, Germany Institut des Recherche en Ecologie Tropicale, (IRET/CENAREST) BP 13545 Libreville, Gabon
Katharina Neumann*
Affiliation:
J.W. Goethe-Universität, Institut für Archäologische Wissenschaften, Abteilung Vor- und Frühgeschichte, Grüneburgplatz 1, D-60323 Frankfurt am Main, Germany
Astrid Schweizer
Affiliation:
J.W. Goethe-Universität, Institut für Archäologische Wissenschaften, Abteilung Vor- und Frühgeschichte, Grüneburgplatz 1, D-60323 Frankfurt am Main, Germany
Jean Maley
Affiliation:
Institut des Sciences de l'Evolution de Montpellier, UMR 5554, Université de Montpellier II, Place Eugène Bataillon, cc 61, 34095 Montpellier Cedex 5, France
*
*Corresponding authors. Email Address:[email protected], [email protected], [email protected]
*Corresponding authors. Email Address:[email protected], [email protected], [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The third millennium BP crisis of the central African rainforest is not sufficiently understood. The low resolution of most pollen profiles and a large plateau of the calibration curve aggravate the exact dating of the event, and its causal climatic parameters are debated. We present a high-resolution pollen profile from the swamp site Nyabessan in the southern Cameroonian rainforest, covering the period 3100-2300 cal yr BP. Between 3100 and 2500 cal yr BP, the climate was favourable for a regional evergreen forest with Caesalpiniaceae and Lophira and a local Raphia swamp forest. Around 2500/2400 cal yr BP, a significant decrease of mature forest and swamp forest taxa and an increase of pioneers indicate that the rain forest was seriously disturbed and replaced by secondary formations. The dominance of Trema orientalis, a pioneer well adapted to seasonal desiccation, points to a much more accentuated seasonality after 2500 cal yr BP, which seems to be linked to a southwards shift of the ITCZ during the northern hemisphere winter months. We propose that the rain forest crisis between 2500 and 2200 cal BP created favourable conditions for farming and paved the way for a major expansion of Bantu speaking populations.

Keywords

Climatic changeSeasonalityITCZpioneer forestTrema orientalisBantu expansion
Type
Articles
Information
Quaternary Research , Volume 71 , Issue 3 , May 2009 , pp. 307 - 318
Copyright
University of Washington

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Achoundong, G., (1985). Etude écologique et floristique de la végétation des collines de Yaoundé au dessus de 1000 m. Unpublished Ph.D. thesis, Université Yaoundé, Cameroun.Google Scholar
Alexandre, D.-Y. Observation sur l'écologie de Trema guineensis en basse Côte d'Ivoire. Cahiers ORSTOM, série Biologie 13, (1978). 261–266.Google Scholar
Blaauw, M., Heudelink, G.B.M., Mauquoy, D., van der Plicht, J., and van Geel, B. A numerical approach to 14C wiggle-match dating of organic deposits: best fit and confidence intervals. Quaternary Science Reviews 22, (2003). 1483–1500.Google Scholar
Blaauw, M., van Geel, B., Mauquoy, D., and van der Plicht, J. Carbon-14 wiggle-match dating of peat deposits: advantages and limitations. Journal of Quaternary Science 19, (2004). 177–181.Google Scholar
Bonnefille, R., and Riollet, G. Pollens des Savanes d'Afrique Orientale. (1980). C.N.R.S, Paris.Google Scholar
Breunig, P., and Neumann, K. Continuity or discontinuity? The 1st millennium BC-crisis in West African prehistory. Lenssen-Erz, T. et al. Tides of the Desert - Gezeiten der Wüste. Contributions to the Archaeological and Environmental History of African in Honour of Rudolph Kuper. Africa Praehistorica 14. (2002). Heinrich-Barth-Institut, Cologne. 495–505.Google Scholar
Brncic, T.M., Willis, K.J., Harris, D.J., and Washington, R. Cultural or climate? The relative influences of past processes on the composition of the lowland Congo rainforest. Philosophical Transactions of the Royal Society B 362, (2007). 229–242.Google Scholar
Casey, J. Holocene occupations of the forest and savanna. Stahl, A.B. African Archaeology: a Critical Introduction. (2005). Blackwell, Oxford. 225–248.Google Scholar
Clark, J.S. Particle motion and the theory of charchoal analysis: source area, transport, deposition, and sampling. Quaternary Research 30, (1988). 67–80.Google Scholar
Clement, R.M., and Horn, S.P. Pre-Columbian land-use history in Costa Rica: a 3000-year record of forest clearance, agriculture, and fire from Laguna Zoncho. The Holocene 11, (2001). 419–426.Google Scholar
Coombe, D.E., and Hadfield, W. An analysis of the growth of Musanga cecropioides . Journal of Ecology 50, (1962). 221–234.CrossRefGoogle Scholar
Diamond, J., and Bellwood, P. Farmers and their languages: the first expansion. Science 300, (2003). 597–603.CrossRefGoogle Scholar
Eggert, M.K.H. The Bantu problem and African archaeology. Stahl, A.B. African Archaeology: A Critical Introduction. (2005). Blackwell, Oxford. 301–326.Google Scholar
Eggert, M.K.H., Höhn, A., Kahlheber, S., Meister, C., Neumann, K., and Schweizer, A. Pits, graves and grains: archaeological and archaeobotanical research in southern Cameroon. Journal of African Archaeology 4, (2006). 273–298.Google Scholar
Ehret, C., and Posnansky, M. The Archaeological and Linguistic Reconstruction of African History. (1982). University of California Press, Berkeley.Google Scholar
Elenga, H., Schwartz, D., Vincens, A., Bertaux, J., de Namur, C., Martin, L., Wirrmann, D., and Servant, M. Diagramme pollinique holocène du Lac Kitina (Congo): mise en évidence de changements paléobotaniques et paléoclimatiques dans le massif forestier du Mayombe. Comptes Rendus de l'Academie des Sciences, Series IIA, Earth and Planetary Science 323, (1996). 345–356.Google Scholar
Elenga, H., de Namur, C., Vincens, A., Roux, M., and Schwartz, D. Use of plots to define pollen-vegetation relationships in densely forested ecosystems of tropical Africa. Review of Palaeobotany and Palynology 112, (2000). 79–96.Google Scholar
Faegri, K., and Iversen, J. Text Book of Modern Pollen Analysis. (1989). Wiley, Chichester.Google Scholar
Gasse, F. Hydrological changes in the African tropics since the Last Glacial Maximum. Quaternary Science Reviews 19, (2000). 189–211.Google Scholar
Gasse, F., and Van Campo, E. Abrupt post-glacial climate events in West Asia and North Africa monsoon domains. Earth and Planetary Science Letters 126, (1994). 435–456.Google Scholar
Giresse, P., Maley, J., and Kossoni, A. Sedimentary environmental changes and millennial climatic variability in a tropical shallow lake (Lake Ossa, Cameroon) during the Holocene. Palaeogeography, Palaeoclimatology, Palaeoecology 218, (2005). 257–285.Google Scholar
Haberle, S.G. Prehistoric human impact on rainforest biodiversity in highland New Guinea. Philosophical Transactions of the Royal Society B 362, (2007). 219–228.Google Scholar
Hart, T., Hart, J.A., Dechamps, R., Fournier, M., and Ataholo, M. Changes in forest composition over the last 4000 years in the Ituri basin, Zaire. Van der Maesen, L.J.G., Van der Burgt, X.M., and Van Medenbach de Rooy, J.M. The Biodiversity of African Plants. (1996). Kluwer, Dordrecht/Boston/London. 545–563.Google Scholar
Hladik, A., and Dounias, E. Wild yams of the African forest as potential food resources. Hladik, C.M., Hladik, A., Pagezy, H., Linares, O., Koppert, G.J.A., and Froment, A. Tropical Forests, People and Food: Biocultural Interactions and Applications to Development. (1993). UNESCO, Paris. 163–176.Google Scholar
Höhn, A., Kahlheber, S., Neumann, K., and Schweizer, A. Settling the rain forest - the environment of farming communities in southern Cameroon during the first millennium BC. Runge, J. Dynamics of Forest Ecosystems in Central Africa During the Holocene. Palaeoecology of Africa 28. (2007). Taylor and Francis, London. 47–59.Google Scholar
Jolly, D., Bonnefille, R., Burcq, S., and Roux, M. Représentation pollinique de la forêt dense humide du Gabon, tests statistiques. Comptes Rendus de l'Academie des Sciences, Series IIA, Earth and Planetary Science 322, (1996). 63–70.Google Scholar
Kahlheber, S., Neumann, K., Bostoen, K., submitted for publication. Early plant cultivation in the Central African rain forest: first millennium BC pearl millet from South Cameroon. Journal of African History.Google Scholar
Kröpelin, S., Verschuren, D., Lezine, A.-M., Eggermont, H., Cocquyt, C., Francus, P., Cazet, J.-P., Fagot, M., Rumes, D., Russell, J.M., Darius, F., Conley, D.J., Schuster, M., von Suchodoletz, H., and Engstrom, D.R. Climate-driven ecosystem succession in the Sahara: the past 6000 years. Science 320, (2008). 765–768.Google Scholar
Lavachery, P., MacEachern, S., Bouimon, T., Gouem, B.G., Kinyock, P., Mbairo, J., and Nkokonda, O. Komé to Ebomé: Archaeological research for the Chad Export Project, 1999-2003. Journal of African Archaeology 3, (2005). 175–193.CrossRefGoogle Scholar
Leroux, M. Le climat de l'Afrique tropicale. (1983). Champion, Paris.Google Scholar
Letouzey, R. Etude Phytogéographique du Cameroun. (1968). Paul Lechevallier, Paris.Google Scholar
Letouzey, R. Notice de la carte phytogéographique du Cameroun au 1: 500.000. (1985). Institut de la Carte Internationale de la Végetation, Toulouse.Google Scholar
Letouzey, R., and Fotius, G. Carte phytogéographique du Cameroun, 1: 500.000. (1985). Institut de la Carte Internationale de la Végetation, Toulouse.Google Scholar
Maley, J. Mise en évidence d'une péjoration climatique entre ca 2500 et 2000 ans BP en Afrique tropicale humide. Bulletin de la Société Géologique de France 163, (1992). 363–365.Google Scholar
Maley, J. A catastrophic destruction of African forests about 2500 years ago still exerts a major influence on present vegetation formations. IDS Bulletin. 33, (2002). 13–30.CrossRefGoogle Scholar
Maley, J. Les variations de la végétation et des paléoenvironnements du domaine forestier africain au cours du Quaternaire récent. Sémah, A.-M., and Renault-Miskovsky, J.L. Évolution de la Végétation Depuis Deux Millions d'années. (2004). Artcom / Errance, Paris. 143–178.Google Scholar
Maley, J., and Brenac, P. Vegetation dynamics, paleoenvironments and climatic changes in the forests of western Cameroon during the last 28,000 years B.P. Review of Palaeobotany and Palynology 99, (1998). 157–187.Google Scholar
Maley, J., and Chepstow-Lusty, A. Elaeis guineensis Jacq. (oil palm) fluctuations in central Africa during the late Holocene: climate or human driving forces for this pioneering species?. Vegetation History and Archaeobotany 10, (2001). 117–120.Google Scholar
Meister, C. Recent archaeological investigations in the tropical rain forest of south-west Cameroon. Runge, J. Dynamics of Forest Ecosystems in Central Africa during the Holocene. Palaeoecology of Africa 28. (2007). Taylor and Francis, London. 43–54.Google Scholar
National Research Council Lost Crops of Africa. Vol. 1, Grains. (1996). National Academy Press, Washington D.C..Google Scholar
Ngomanda, A., (2005). Dynamique des écosystèmes forestiers du Gabon au cours des cinq derniers millénaires. Unpublished Ph.D. thesis, Université Montpellier II, France.Google Scholar
Nguetsop, V.F., Servant-Vildary, S., and Servant, M. Late Holocene climatic changes in West Africa, a high resolution diatom record from equatorial Cameroon. Quaternary Science Reviews 23, (2004). 591–609.Google Scholar
Nicholson, S.E. The nature of rainfall variability over Africa on time scales of decades to millenia. Global and Planetary Change 26, (2000). 137–158.Google Scholar
Nounamo, L., and Yemefack, M. Shifting Cultivation in the Evergreen Forest of Southern Cameroon: Farming Systems and Soil Degradation. (2000). Tropenbos-Cameroon, Kribi.Google Scholar
Oslisly, R. Les traditions culturelles de l'Holocène sur le littoral du Cameroun entre Kribi et Campo. Wotzka, H.-P. Grundlegungen. (2006). Beiträge zur europäischen und afrikanischen Archäologie für Manfred K.H. Eggert. Francke, Tübingen. 303–317.Google Scholar
Oslisly, R., and White, L. Human impact and environmental exploitation in Gabon during the Holocene. Denham, T., Iriarte, J., and Vrydaghs, L. Rethinking Agriculture. Archaeological and Ethnoarchaeological Perspectives. (2007). Left Coast Press, Walnut Creek. 347–360.Google Scholar
Phillipson, D.W. African Archaeology. (1993). Cambridge University Press, Cambridge.Google Scholar
Piperno, D.R., and Becker, P. Vegetation history of a site in the Central Amazon basin derived from phytolith and charcoal records from natural soils. Quaternary Research 45, (1996). 202–209.Google Scholar
Piperno, D.R., and Pearsall, D.M. The Origins of Agriculture in the Lowland Neotropics. (1998). Academic Press, San Diego.Google Scholar
Purseglove, J.W.' Tropical Crops: Monocotyledons. English Language Book Society. (1972). Longman, Harlow.Google Scholar
Reimer, P.J., Baillie, M.G.L., Bard, E., Bayliss, A., Beck, J.W., Bertrand, C.J.H., Blackwell, P.G., Buck, C.E., Burr, G.S., Cutler, K.B., Damon, P.E., Edwards, R.L., Fairbanks, R.G., Friedrich, M., Guilderson, T.P., Hogg, A.G., Hughen, K.A., Kromer, B., McCormac, G., Manning, S., Ramsey, C.B., Reimer, R.W., Remmele, S., Southon, J.R., Stuiver, M., Talamo, S., Taylor, F.W., van der Plicht, J., and Weyhenmeyer, C.E. INTCAL04 Terrestrial Radiocarbon age calibration, 0-26 cal kyr B.P. Radiocarbon 46, (2005). 1029–1058.Google Scholar
Reynaud, I., and Maley, J. Histoire récente d'une formation forestière du sud-ouest du Cameroun à partir de l'analyse pollinique. Comptes Rendus de l'Academie des Sciences, Series IIA, Earth and Planetary Science 337, (1994). 575–580.Google Scholar
Reynaud-Farrera, I., (1995). Histoire des paléoenvironnements forestiers du Sud-Cameroun à partir d'analyses palynologiques et statistiques des dépôts holocènes et actuels. Unpublished Ph.D. thesis, Université Montpellier II, France.Google Scholar
Reynaud-Farrera, I., Maley, J., and Wirrmann, D. Végétation et climat dans les forêts du Sud-Ouest Cameroun depuis 4770 ans B.P: analyse pollinique des sédiments du Lac Ossa. Comptes Rendus de l'Academie des Sciences, Series IIA, Earth and Planetary Science 322, (1996). 749–755.Google Scholar
Richards, P.W. The Tropical Rain Forest: an Ecological Study. (1996). Cambridge University Press, Cambridge.Google Scholar
Riéra, B., and Alexandre, D.Y. Surface des chablis et temps de renouvellement en forêt dense tropicale. Acta Oecologica 9, (1988). 221–230.Google Scholar
Ross, R. Ecological studies on the rain forest of southern Nigeria. III. Secondary succession in the Shasha Forest Reserve. Journal of Ecology 42, (1954). 259–282.Google Scholar
Salzmann, U., and Hoelzmann, P. The Dahomey Gap: an abrupt climatically induced rain forest fragmentation in West Africa during the late Holocene. The Holocene 15, (2005). 190–199.Google Scholar
Salzmann, U., and Waller, M. The Holocene pollen of the Nigerian Sahel based on multiple profiles. Review of Palaeobotany and Palynology 100, (1998). 39–72.Google Scholar
Sangen, M. New evidence on palaeoenvironmental conditions in SW Cameroon since the Late Pleistocene derived from alluvial sediments of the river Ntem. Runge, J. Dynamics of Forest Ecosystems in Central Africa During the Holocene. Palaeoecology of Africa 28. (2007). Taylor and Francis, London. 79–101.Google Scholar
Schwartz, D. Assèchement climatique vers 3000 B.P. et expansion Bantu en Afrique Centrale atlantique: quelques réflexions. Bulletin de la Société Géologique de France 163, 3 (1992). 353–361.Google Scholar
Shanahan, T.M., Overpeck, J.T., Wheeler, C.W., Beck, J.W., Pigati, J.S., Talbot, M.R., Scholz, C.A., Peck, J., and King, J.W. Paleoclimatic variations in West Africa from a record of late Pleistocene and Holocene lake level stands of Lake Bosumtwi, Ghana. Palaeogeography, Palaeoclimatology, Palaeoecology 242, (2006). 287–302.Google Scholar
Sowunmi, M.A. The significance of the oil palm (Elaeis guineensis Jacq.) in the late Holocene environments of west and west central Africa: a further consideration. Vegetation History and Archaeobotany 8, (1999). 199–210.Google Scholar
Street-Perrott, F.A., Holmes, J.A., Waller, M.P., Allen, M.J., Barber, N.G.H., Fothergill, P.A., Harkness, D.D., Ivanovich, M., Kroon, D., and Perrott, R.A. Drought and dust deposition in the West African Sahel: a 5500-year record from Kajemarum Oasis, northeastern Nigeria. The Holocene 10, 3 (2000). 293–302.Google Scholar
Swaine, M.D., and Hall, J.B. Early succession on cleared forest land in Ghana. Journal of Ecology 71, (1983). 601–627.Google Scholar
Tchouto Mbatchou, G.P., (2004). Plant Diversity in a Tropical African Rain Forest. Unpublished Ph.D. thesis, Wageningen University, The Netherlands.Google Scholar
Van der Meer, P.J., and Bonger, F. Formation and closure of canopy gaps in the rain forest at Nouragues, French Guiana. Vegetatio 126, (1996). 167–179.Google Scholar
Van Gemerden, B.S., Shu, G.N., and Olff, H. Recovery of conservation values in Central African rain forest after logging and shifting cultivation. Biodiversity and Conservation 12, (2003). 1553–1570.Google Scholar
Vansina, J. Western Bantu expansion. Journal of African History 25, (1984). 129–145.Google Scholar
Vansina, J. Paths in the Rainforests: Toward a History of Political Tradition in Equatorial Africa. (1990). University of Wisconsin Press, Madison.Google Scholar
Vansina, J. New linguistic evidence and 'The Bantu expansion'. Journal of African History 36, (1995). 173–195.Google Scholar
Vincens, A., Buchet, G., Elenga, H., Fournier, M., Martin, L., de Namur, C., Schwartz, D., Servant, M., and Wirrmann, D. Changement majeur de la végétation du lac Sinnda (vallée du Niari, Sud Congo) consécutif à un l'assèchement climatique holocène supérieur: apport de la palynologie. Comptes Rendus de l'Academie des Sciences, Series IIA, Earth and Planetary Science 318, (1994). 1521–1526.Google Scholar
Vincens, A., Schwartz, D., Bertaux, J., Elenga, H., and de Namur, C. Late Holocene climatic changes in Western Equatorial Africa inferred from pollen from Lake Sinnda, Southern Congo. Quaternary Research 50, (1998). 34–45.Google Scholar
Vincens, A., Schwartz, D., Elenga, H., Reynaud-Farrera, I., Alexandre, A., Bertaux, J., Mariotti, A., Martin, L., Meunier, J.-D., Nguetsop, F., Servant, M., Servant-Vildary, S., and Wirrmann, D. Forest response to climate changes in Atlantic Equatorial Africa during the last 4000 years BP and inheritance on the modern landscapes. Journal of Biogeography 26, (1999). 879–885.Google Scholar
Waller, M.P., Street-Perrott, F.A., and Wang, H. Holocene vegetation history of the Sahel: pollen, sedimentological and geochemical data from Jikariya Lake, north-eastern Nigeria. Journal of Biogeography 35, 9 (2007). 1575–1590.Google Scholar
Weldeab, S., Kölling, M., and Wefer, G. Holocene African droughts related to eastern equatorial Atlantic cooling. Geology 33, (2005). 981–984.Google Scholar
Weldeab, S., Lea, D.W., Schneider, R., and Andersen, N. 155,000 years of West African monsoon and ocean thermal evolution. Science 316, (2007). 1303–1307.Google Scholar
White, L.J.T., and Oates, J.F. New data on the history of the plateau forest of Okumu, southern Nigeria: an insight into how human disturbance has shaped the African rain forest. Global Ecology and Biogeography 8, (1999). 355–361.Google Scholar
Wotzka, H.-P. Records of activity: radiocarbon and the structure of Iron Age settlement in Central Africa. Wotzka, H.-P. Grundlegungen. (2006). Beiträge zur europäischen und afrikanischen Archäologie für Manfred K.H. Eggert. Francke, Tübingen. 271–289.Google Scholar
Ybert, J.-P. Atlas de pollens de Côte d'Ivoire. (1979). ORSTOM, Paris.Google Scholar
Zapfack, L., Engwald, S., Sonke, B., Achoundong, G., and Madong, B.A. The impact of land conversion on plant biodiversity in the forest zone of Cameroon. Biodiversity and Conservation 11, (2002). 2047–2061.Google Scholar