Aleman J.C., Blarquez O., Bentaleb I., Bonté P., Brossier B., Carcaillet C., Gond V., Gourlet-Fleury S., Kpolita A., Lefèvre I., Oslisly Richard, Power M.J., Yongo O., Bremond L., Favier C. (2013). Tracking land-cover changes with sedimentary charcoal in the Afrotropics. The Holocene, 23 (12), p. 1853-1862. ISSN 0959-6836.
Titre du document
Tracking land-cover changes with sedimentary charcoal in the Afrotropics
Année de publication
2013
Auteurs
Aleman J.C., Blarquez O., Bentaleb I., Bonté P., Brossier B., Carcaillet C., Gond V., Gourlet-Fleury S., Kpolita A., Lefèvre I., Oslisly Richard, Power M.J., Yongo O., Bremond L., Favier C.
Source
The Holocene, 2013,
23 (12), p. 1853-1862 ISSN 0959-6836
Fires have played an important role in creating and maintaining savannas over the centuries and are also one of the main natural disturbances in forests. The functional role of fires in savannas and forests can be investigated through examining sedimentary charcoal in order to reconstruct long-term fire history. However, the relationship between charcoal and vegetation structure in tropical grassy ecosystems remains to be elucidated. Here, we compared recent charcoal records from lake sediments in three tropical ecosystems (forest, savanna, and forestsavanna mosaic) with land cover inferred from remote-sensing images. Charcoal width-to-length (W/L) ratio is a good proxy for changes in fuel type. At one of the lakes, a significant W/L modification from values >0.5 (mainly wood) to <0.5 (grass) was recorded simultaneously with changes in land cover. Indeed, a significant deforestation was recorded around this lake in the remote-sensing imagery between 1984 and 1994. The results also indicate that a riparian forest around a lake could act as a physical filter for charcoal accumulation; we used the mean charcoal size as a proxy to evaluate this process. Charcoal Accumulation Rates (CHAR), a burned biomass proxy, were combined with W/L ratio and the mean charcoal size to investigate the land-use history of the landscapes surrounding the study sites. This combined approach allowed us to distinguish between episodic slash-and-burn practices in the forest and managed fields or pastures burning frequently.
Plan de classement
Sédimentologie [064SEDIM]
;
Etudes régionales [112ARCHEO02]
Descripteurs
PALEOENVIRONNEMENT ; COUVERT VEGETAL ; SAVANE ; FORET ; MOSAIQUE FORET SAVANE ; SEDIMENTATION LACUSTRE ; CHARBON ; IMAGE SATELLITE ; UTILISATION DU SOL ; HOLOCENE ; INCENDIE ; FEU
Description Géographique
ZONE TROPICALE ; CENTRAFRIQUE
Localisation
Fonds IRD [F B010060197]
Identifiant IRD
fdi:010060197
