Diatom based transfer function for estimating the chemical composition of fossil water. Calibration based on salt lakes of the Lipez area in the southwestern Bolivian Altiplano

Simone Servant-Vildary (1) , François Risacher (2) , Maurice Roux (3)

1 Laboratoire de Géologie
2 CGS - Centre de géochimie de la surface
3 IMEP - Institut Méditerranéen d'Ecologie et de Paléoécologie

Diatom assemblages and water chemistry were studied in 13 shallow salt lakes in the southern part of the Bolivian Altiplano. At each locality bottm sediment and water samples were collected simultaneously. Relationships between the composition of the diatom assemblages and variations in water chemistry were collated in order to permit the estimation of ancient water chemistries based on changes in the make up of fossil diatom associations in older sediments. Weighted Averages treated by Partial Least Squares regression (WA and WA-PLS methods) allowed an estimation of optima and the relative tolerances of 61 species to variations in salinity and to the relative quantities of the 15 chemical elements studied, among them boron and lithium.

Mots clés: flora; diatom; Bolivia; Quaternary; water ionic content; water chemistry; transfer function; ecology

Domaines: Paléontologie

Simone Servant-Vildary, François Risacher, Maurice Roux. Diatom based transfer function for estimating the chemical composition of fossil water. Calibration based on salt lakes of the Lipez area in the southwestern Bolivian Altiplano. Carnets de Géologie / Notebooks on Geology, 2002, CG2002 (M01-en), pp.1-36. ⟨hal-00141495⟩