%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Garcin Y.
%A Deschamps, Pierre
%A Ménot, G.
%A Saulieu, Geoffroy de
%A Schefuss, E.
%A Sebag, David
%A Dupont, L.M.
%A Oslisly, Richard
%A Brademann, B.
%A Mbusnum, K.G.
%A Onama, J.M.
%A Ako, A.A.
%A Epp, L.S.
%A Tjallingii, R.
%A Strecker,  M.R.
%A Brauer, A.
%A Sachse, D.
%T Early anthropogenic impact on western central African rainfrorests 2,600 y ago
%D 2018
%L fdi:010072522
%G ENG
%J Proceedings of the National Academy of Sciences of the United States
%@ 0027-8424
%K PALEOENVIRONNEMENT ; PALEOCLIMAT ; HOLOCENE ; FORET ; MOSAIQUE FORET SAVANE ; FACTEUR ANTHROPIQUE ; HYDROLOGIE ; LAC ; HISTOIRE DU PEUPLEMENT
%K CAMEROUN SUD OUEST ; ZONE TROPICALE
%K BAROMBI LAC
%M ISI:000428382400038
%N 13
%P 3261-3266
%R 10.1073/pnas.1715336115
%U https://www.documentation.ird.fr/hor/fdi:010072522
%> https://www.documentation.ird.fr/intranet/publi/depot/2018-04-16/010072522.pdf
%V 115
%W Horizon (IRD)
%X A potential human footprint on Western Central African rainforests before the Common Era has become the focus of an ongoing controversy. Between 3,000 y ago and 2,000 y ago, regional pollen sequences indicate a replacement of mature rainforests by a forest–savannah mosaic including pioneer trees. Although some studies suggested an anthropogenic influence on this forest fragmentation, current interpretations based on pollen data attribute the "rainforest crisis" to climate change toward a drier, more seasonal climate. A rigorous test of this hypothesis, however, requires climate proxies independent of vegetation changes. Here we resolve this controversy through a continuous 10,500-y record of both vegetation and hydrological changes from Lake Barombi in Southwest Cameroon based on changes in carbon and hydrogen isotope compositions of plant waxes. δ13C-inferred vegetation changes confirm a prominent and abrupt appearance of C4 plants in the Lake Barombi catchment, at 2,600 calendar years before AD 1950 (cal y BP), followed by an equally sudden return to rainforest vegetation at 2,020 cal y BP. δD values from the same plant wax compounds, however, show no simultaneous hydrological change. Based on the combination of these data with a comprehensive regional archaeological database we provide evidence that humans triggered the rainforest fragmentation 2,600 y ago. Our findings suggest that technological developments, including agricultural practices and iron metallurgy, possibly related to the large-scale Bantu expansion, significantly impacted the ecosystems before the Common Era.
%$ 112ARCHEO02 ; 021ENVECO ; 021CLIMAT01