Establishment and functioning of the savanna marshes of the Lopé National Park in Gabon since the termination of the African humid period and the arrival of humans 2500 years ago
Year: 2021
Type: article
Abstract: Holocene paleoecological studies in tropical Africa are rare because most lakes either dried out at the termination of the African Humid Period or have since filled up. However, tropical sedge marshes can be an alternative to perform long-term ecological studies. The Lopé National Park (LNP) in Gabon is a mosaic of forest and savanna enclosed in the equatorial forest, where open areas facilitated the development of peat marshes accumulating several-meter-thick sediment. In order to reconstruct the historical dynamic in these marshes through a local and regional point of view, we compared sedimentological, continuous X-ray fluorescence, and stable isotopic analyses on sediment cores from six herbaceous marshes in the LNP. A reliable chronological frame was based on 50 14 C dates, over the last 2500 years in most sites, and reaching 9000 years in one marsh. We show that the origin of these marshes is a major hydrological change, 3450 and 2300 years ago, that affected the entire region, almost concomitantly with the diffusion of Iron Age population. The sedimentation within marshes is homogenous with low intra-site variability. In contrast, high inter-sites variability evidences that the functioning of the marsh itself exerts a much more significant influence than in lakes. However, a regional event is recorded between 1400 and 800 years ago, concurrently with an archeological trace hiatus throughout the forest hinterland of West Central Africa.
Source: The Holocene
Institutions: École Pratique des Hautes Études, Université de Montpellier, Institut des Sciences de l'Evolution de Montpellier, National Agency for National Parks, Institut de Recherche pour le Développement, Patrimoines locaux, Environnement et Globalisation, Centre National de la Recherche Scientifique, IFP Énergies nouvelles, Normandie Université, Université de Caen Normandie, Université des Sciences et Techniques de Masuku
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Life on land
Open Access status: green
OpenAlex ID: W3145732701