Le rôle de l’évolution des paysages holocènes dans le comblement des bas-fonds du Parc national de la Lopé, moyenne vallée de l’Ogooué au Gabon

Abstract : Sedimentological and geochemical analyses and 14C dating were performed for a sedimentary core sample from the Lopé 2 marsh in the northern zone of Gabon’s Lopé National Park. The results produced a division of the core sample into three main units. The basal part of the core sample was dated to 2,320 years cal BP. At this time, the Lopé 2 marsh was a topographic hollow that flooded sporadically during the rainy season. This unit corresponds to a soil formation of clay, quartz and highly decomposed organic matter. The upper boundary of this unit corresponds to the end of the climatic deterioration that affected central Africa around 2,500 years BP. The second unit represents the period from 2,320 to 585 years cal BP. This shows a gradual decrease in the flow of quartz that reflects the increasing relative density of the marsh vegetation as the climate became more humid. The organic matter in this unit is of mixed origin, relatively abundant and with a high content of refractory material. The third unit, representing the period from 585 years cal BP to the present, shows plant cover associated with developing marshland (which began in unit 2) that was sustained by the humid climate. The organic matter here is rich in biological material.
Complete list of metadatas

Cited literature [31 references]  Display  Hide  Download

https://hal-univ-perp.archives-ouvertes.fr/hal-01741839
Contributor : Dorian Miler <>
Submitted on : Friday, March 23, 2018 - 2:41:56 PM
Last modification on : Thursday, October 24, 2019 - 9:54:26 AM
Long-term archiving on: Thursday, September 13, 2018 - 7:20:19 AM

File

31469-32407-1-PB.pdf
Publisher files allowed on an open archive

Identifiers

  • HAL Id : hal-01741839, version 1

Citation

Victory Nfoumou Obame, Makaya M'Voubou, David Sebag, Richard Oslisly, Laurent Bremond, et al.. Le rôle de l’évolution des paysages holocènes dans le comblement des bas-fonds du Parc national de la Lopé, moyenne vallée de l’Ogooué au Gabon. Bois et Forêts des Tropiques, Montpellier : CIRAD, 2017, 333 (3), pp.67-77. ⟨hal-01741839⟩

Share

Metrics

Record views

308

Files downloads

89