Голод 1946–1947 рр. як продовження геноциду і антиукраїнської політики влади

International audienceA diatom study, carried out on a core recovered in the Southern Altiplano (Coipasa salt lake 19 degrees S, 68 degrees W) currently almost completely dry, shows that during the last glacial maximum the Coipasa salar was entirely occupied by a large shallow lake. Available data for the northern Altiplano (Lake Titicaca, 16 degrees S, 69 degrees W) indicate a water level 17 m lower than today. This opposition is explained by decreased tropical precipitations whose effects registered by Lake Titicaca were obliterated in the Coipasa salar by increased winter precipitation. ((C) Academie des sciences/Elsevier, Paris.)

Кераміка для техніки

The benthic invertebrates fauna of most of the saline lakes of the Sud Lipez region (Bolivia, Altiplano) has been until now quite unstudied. Samples collected during an extensive survey of 12 lakes and two small inflow rivers allow a first list of the main macroinvertebrates living in the biotopes. The heterogeneous nature of these saline lakes with their freshwater springs and phreatic inflows offers a variety of habitats to macroinvertebrates. The benthic fauna in lakes with salinity > 10 g l-1 is not so low in density but includes few species and is dominated by Orthocladinae and Podonominae larvae. In contrast, the freshwater springs and inflows are colonized by a diverse fauna with a mixture of both freshwater and saline taxa, but dominated by Elmidae and Amphipoda. The lakes are quite isolated and, apart from some cosmopolitan organisms, their fauna can be quite distinctive. (Résumé d'auteur

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

Diatom assemblages and water chemistry were studied in 13 shallow salt lakes in the southern part of the Bolivian Altiplano. At each locality bottom 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.L'étude des assemblages de diatomées et de la composition chimique des eaux a été effectuée dans 13 lacs salés peu profonds localisés dans le Sud de l'Altiplano Bolivien. Les points et les dates de prélèvement sont les mêmes pour les deux types d'étude. Les relations entre les assemblages de diatomées et les variables chimiques mesurées sont effectuées dans le but d'estimer ces variables dans le passé à partir des diatomées fossiles conservées dans les sédiments. La méthode des moyennes pondérées (WA et WA-PLS régression) a permis d'estimer les optima et les tolérances de 61 espèces à la salinité et aux différents éléments chimiques dont le bore et le lithium

The Last Glacial Maximum (21,000 to 17,000 C-14 years BP) in the tropical Andes (Bolivia) based on diatom studies - Reply

International audienc

Diatom-based ionic concentration and salinity models from the south Bolivian Altiplano (15-23 degrees S)

International audienceThe relationship between surface sediment diatom assemblages and measured limnological variables in fifty eight lake samples from the south Bolivian Altiplano was examined by constructing a diatom-water chemistry dataset. Analysis of this dataset by canonical correspondence analysis revealed that salinity and ionic concentration accounted for a significant amount of the variation in the distribution of the diatom assemblages. Two methods `weighted-averaging regression and calibration', and `by-class mean percentage table' were used to established a transfer function for future reconstruction of past lake water salinity and ionic concentration in the southern Bolivian Altiplano. Weighted-averaging regression and calibration with inverse deshrinking provided a better model for the water chemistry reconstructions in this region