IBBEA   24401
INSTITUTO DE BIODIVERSIDAD Y BIOLOGIA EXPERIMENTAL Y APLICADA
Unidad Ejecutora - UE
artículos
Título:
Little Ice Age to present paleoenvironmental reconstruction based on multyproxy analyses from Nahuel Huapi lake (Patagonia, Argentina)
Autor/es:
MAIDANA NORA; MASSAFERRO JULIETA; GARCIA MARIA LUJAN; LAMI ANDREA; SERRA MARIA NOEL; VILLAROSA GUSTAVO
Revista:
AMEGHINIANA
Editorial:
ASOCIACION PALEONTOLOGICA ARGENTINA
Referencias:
Lugar: Buenos Aires; Año: 2016 vol. 53 p. 58 - 73
ISSN:
0002-7014
Resumen:
Lakes are ideal sites to study environmental changes since they preserve climatic, anthropogenic, and volcanic signals in theirsediments. Brazo Blest is one of the most important ramifications of Lake Nahuel Huapi and it is an interesting site to study climatic variationsas it receives direct discharge of heavy suspended sediments loads from Tronador Glacier through the Frías River, as a result of the abrasionof the bedrock and runoff from the surrounding Valdivian Forest. A short sediment core from Brazo Blest was analyzed for chironomid anddiatom assemblages and pigments in order to reconstruct environmental changes during the last 100 years in the basin under study. Thismultiproxy study also included geochemical and physical analyses and reveals changes in the productivity of the lake over time, showing a shiftin the 1950s from autochthonous to allochthonous organic matter. This modification is related to the increase of precipitation and the consequentfluvial runoff from two catchments, Frías River and the Blest-Cántaros basin together with the effects ofrising temperatures, whichaffected Tronador Glacier. Further, it allows us to link volcanic eruptions to a decrease in species richness and number of chironomids anddiatoms, as a consequence of reduced light intensities and food availability induced by the high content of suspended sediments in the watercolumn. This study highlights the effectiveness of multiproxy analyses to reconstruct environmental changes.