Horizon / Plein textes La base de ressources documentaires de l'IRD

IRD

 

Publications des scientifiques de l'IRD

Cardozo A. Y. V., Gomes D. F., da Silva E. M., Duque S. R. E., Rangel J. O. C., Sifeddine Abdelfettah, Turcq Bruno, Albuquerque A. L. S. (2014). Holocene paleolimnological reconstruction of a high altitude Colombian tropical lake. In : Sifeddine Abdelfettah (ed.), Meyers P.A. (ed.), Valdés J. (ed.), Leite Días da Silva P. (ed.) Continental and coastal marine records of centennial to millennial changes in South American climate since the last glacial maximum. Palaeogeography Palaeoclimatology Palaeoecology, 415 (no spécial), 127-136. ISSN 0031-0182

Accès réservé (Intranet IRD) Demander le PDF

Lien direct chez l'éditeur doi:10.1016/j.palaeo.2014.03.013

Titre
Holocene paleolimnological reconstruction of a high altitude Colombian tropical lake
Année de publication2014
Type de documentArticle référencé dans le Web of Science WOS:000345951000014
AuteursCardozo A. Y. V., Gomes D. F., da Silva E. M., Duque S. R. E., Rangel J. O. C., Sifeddine Abdelfettah, Turcq Bruno, Albuquerque A. L. S.
InSifeddine Abdelfettah (ed.), Meyers P.A. (ed.), Valdés J. (ed.), Leite Días da Silva P. (ed.) Continental and coastal marine records of centennial to millennial changes in South American climate since the last glacial maximum
SourcePalaeogeography Palaeoclimatology Palaeoecology, 2014, 415 (no spécial), p. 127-136. ISSN 0031-0182
RésuméAquatic environments in the high-Andean may be quite vulnerable to climatic conditions and hydrological processes (precipitation/evaporation) that have the potential to alter water levels and chemistry. This study reconstructs the paleohydrological history of Lake Tota, Colombia, to provide a record of environmental changes in the eastern flank of the Colombian Andes during the late Holocene. A 54 cm core was collected at the margin of the lake at a depth of 1.5 m, and the paleohydrological reconstructions were based on changes in diatom assemblages, granulometry, and bulk organic geochemical parameters. The core was subdivided into 5 biozones by assessing the significance of the variance among the CONISS clusters. Biozone T5 (base, 4000 calibrated years BP) was dominated by the planktonic diatom Discostella stelligera and was deposited in a period of high-water level. Sedimentation during this period was rich in carbon due to phytoplanktonic production; the granulometry data suggests that the lake was under high to moderate hydrological dynamic conditions, indicating active deposition at the river delta front. Biozone T4, beginning at 3600 cal. yrs BP, was dominated by three species D. stelligera, Cocconeis placentula var. lineata and Fragilaria sensu lato, and this association could indicate that the lake was under the influence of large fluctuations in water level. This interpretation is supported by granulometry and geochemical data, particularly by the low levels of total organic carbon (TOC). In biozone T3, corresponding to 3000 cal. yrs BP, we found a lowering of the water level, suggested by low levels of TOC. Poor granulometric sorting and higher carbon/nitrogen (C/N) ratios suggest a macrophyte influence on the sedimentation, avoiding direct deltaic influence. In this biozone the benthic diatom F. sensu lato group was dominant. In biozone 12, starting 2400 cal. yrs BP, the proxies indicate that the lake experienced increasing water levels and that stronger circulation patterns occurred in the water column than in the preceding periods, as inferred by the presence of Aulacoseira granulata a ticoplanktonic species. The sediment in this biozone is well sorted and finer, indicating a greater depth. Biozone T1 at the top of the core and since 2000 cal. yrs BP to the present, evidence for a recent reduction in water level of Lake Tota can be deduced by the presence of Achnanthidium minutissimum var. minutissimum.
Plan de classementHydrologie [062] ; Géologie et formations superficielles [064] ; Ecologie, systèmes aquatiques [036]
Descr. géo.COLOMBIE ; ANDES ; ZONE TROPICALE
LocalisationFonds IRD [F B010063597]
Identifiant IRDfdi:010063597
Lien permanenthttp://www.documentation.ird.fr/hor/fdi:010063597

Export des données

Disponibilité des documents

Télechargment fichier PDF téléchargeable

Lien sur le Web lien chez l'éditeur

Accès réservé en accès réservé

HAL en libre accès sur HAL


Accès aux documents originaux :

Le FDI est labellisé CollEx

Accès direct

Bureau du chercheur

Site de la documentation

Espace intranet IST (accès réservé)

Suivi des publications IRD (accès réservé)

Mentions légales

Services Horizon

Poser une question

Consulter l'aide en ligne

Déposer une publication (accès réservé)

S'abonner au flux RSS

Voir les tableaux chronologiques et thématiques

Centres de documentation

Bondy

Montpellier (centre IRD)

Montpellier (MSE)

Cayenne

Nouméa

Papeete

Abidjan

Dakar

Niamey

Ouagadougou

Tunis

La Paz

Quito