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Late Holocene forest contraction and fragmentation in central Africa

Published online by Cambridge University Press:  12 December 2017

Jean Maley*
Affiliation:
Institute de Recherche pour le Développement (IRD), Montpellier Research Center, Agropolis, 34394, cedex 5, France Département Paléoenvironnements, Institut des Sciences de l'Evolution-Montpellier (ISEM-CNRS), Université de Montpellier, F-34095, cedex 5, France
Charles Doumenge
Affiliation:
UPR, Forêts et Societés, Centre International de Recherche Agronomique pour le Développement (CIRAD), Campus International de Baillarguet; Université de Montpellier, F-34398, cedex 5, France
Pierre Giresse
Affiliation:
Centre de Formation et de Recherche sur les Environnements Méditerranéens (CEFREM), Université Via Domitia, Perpignan 66100, France
Gil Mahé
Affiliation:
Institute de Recherche pour le Développement (IRD), Montpellier Research Center, Agropolis, 34394, cedex 5, France Institut de Recherche pour le Développement (IRD) HydroSciences, Université de Montpellier, F-34095, cedex 5, France
Nathalie Philippon
Affiliation:
Institut des Géosciences de l'Environnement, CNRS, INP, IRD, Université de Grenoble Alpes, 38058 Grenoble cedex 9, France
Wannes Hubau
Affiliation:
Royal Museum for Central Africa, Leuvensesteenweg 13, 3080 Tervuren, Belgium
Michel O. Lokonda
Affiliation:
Institut Facultaire des Sciences Agronomiques de Yangambi, IFA, Democratic Republic of the Congo Université Kisangani, R408, Democratic Republic of the Congo
John M. Tshibamba
Affiliation:
Royal Museum for Central Africa, Leuvensesteenweg 13, 3080 Tervuren, Belgium Faculté de Gestion des Ressources Naturelles et Renouvelables, Université Kisangani, R408, Democratic Republic of the Congo
Alex Chepstow-Lusty
Affiliation:
Department of Geography, University of Sussex, Brighton, BN2 4GJ, United Kingdom
*
*Corresponding author at: Institute de Recherche pour le Développement (IRD), Montpellier Research Center, Agropolis, 34394, cedex 5, France, and Département Paléoenvironnement, Institut des Sciences de l'Evolution (ISEM-CNRS) Université de Montpellier, F-34095, cedex 5, France. E-mail address: [email protected] (J. Maley).

Abstract

During the warmer Holocene Period, two major climatic crises affected the Central African rainforests. The first crisis, around 4000 cal yr BP, caused the contraction of the forest in favor of savanna expansion at its northern and southern periphery. The second crisis, around 2500 cal yr BP, resulted in major perturbation at the forest core, leading to forest disturbance and fragmentation with a rapid expansion of pioneer-type vegetation, and a marked erosional phase. The major driver of these two climatic crises appears to be rapid sea-surface temperature variations in the equatorial eastern Atlantic, which modified the regional atmospheric circulation. The change between ca. 2500 to 2000 cal yr BP led to a large increase in thunderstorm activity, which explains the phase of forest fragmentation. Ultimately, climatic data obtained recently show that the present-day major rise in thunderstorms and lightning activity in Central Africa could result from some kind of solar influence, and hence the phase of forest fragmentation between ca. 2500 to 2000 cal yr BP may provide a model for the present-day global warming-related environmental changes in this region.

Type
Tribute to Daniel Livingstone and Paul Colinvaux
Copyright
Copyright © University of Washington. Published by Cambridge University Press, 2017 

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