Lake-level changes in central Patagonia

ARIZTEGUI, DANIEL; GILLI, ADRIAN; ANSELMETTI, FLAVIO; GOÑI, RAFAEL; BELARDI, JUAN BAUTISTA; ESPINOSA, SILVANA LAURA

JOURNAL OF QUATERNARY SCIENCE

JOHN WILEY & SONS LTD

Año: 2010 vol. 25 p. 1092 - 1099

0267-8179

The role and extent of climate as a cause of the expansion and decline of human culturesis still debatable. It is clear, however, that human–environment interactions are enhanced andinterplay more closely in climatically sensitive areas such as around hydrologically closed basins.Lago Cardiel is located at 498 S in the very arid rain shadow east of the Andes, providing anexceptionally receptive system to changes in hydrological balance. Results of a geophysical surveycombined with sedimentological and geochemical studies provide a continuous Lateglacial–Holocenerecord of substantial water-level changes. These variations, combined with archaeological resultsfrom the catchment area, offer a unique possibility to explore the pattern of peopling within this remotearea of the globe and its possible relation to climate change. Human occupation in Patagonia is welldocumented towards the Andes throughout the entire Holocene. Archaeological data from the LagoCardiel basin, however, show an apparent lack of human activity during the first part of this period,which coincides with well-constrained high lake levels. Our results show an intriguing coincidencebetween low lake level and increasing human occupation, suggesting that the Lago Cardiel basin hasfocused human use during intervals with relatively lower effective moisture such as during the LatePleistocene, but its evidence may have been submerged. This interpretation is confirmed by archaeologicalremains from Lago Strobel, another perennial lake with a comparable catchment located inthe same climatic region and thus sharing the same climatic history as Lago Cardiel.