| Text | 386459 2016 10.5710/aMGH.14.09.2015.2912 Scopus 2 s2.0 84961588436 Chironomids Diatoms Lake sediments Paleoenvironmental reconstruction Patagonia Pigments Little ice age to present paleoenvironmental reconstruction based on multiproxy analyses from Nahuel Huapi lake Patagonia, Argentina Serra M.N.; Garcia M.L.; Maidana N.; Villarosa G.; Lami A.; Massaferro J. CENAC, Programa de Estudios Aplicados A la Conservacion Del Parque Nacional Nahuel Huapi, Concejo Nacional de Investigaciones Cientificas y Tecnicas CONICET , Administracion de Parques Nacionales APN , Fagnano 244, San Carlos de Bariloche, Rio Negro, R8400BCL, , , Argentina; CENAC, Programa de Estudios Aplicados A la Conservacion Del Parque Nacional Nahuel Huapi, Concejo Nacional de Investigaciones Cientificas y Tecnicas CONICET , Administracion de Parques Nacionales APN , Fagnano 244, San Carlos de Bariloche, Rio Negro, R8400BCL, , , Argentina; Laboratorio de Diatomeas Continentales, Departamento de Biodiversidad y Biologia Experimental DBBE , Facultad de Ciencias Exactas y Naturales FCEN , Universidad de Buenos Aires UBA , , Argentina; Instituto de Biodiversidad y Biologia Experimental y Aplicada IBBEA , Universidad de Buenos Aires UBA , Concejo Nacional de Investigaciones Cientificas y Tecnicas CONICET , Ciudad Universitaria, Pabellon 2, CABA, , , Argentina; Instituto de Biodiversidad y Biologia Experimental y Aplicada IBBEA , Universidad de Buenos Aires UBA , Concejo Nacional de Investigaciones Cientificas y Tecnicas CONICET , Ciudad Universitaria, Pabellon 2, CABA, , , Argentina; Consiglio Nazionale Delle Ricerche CNR , Istituto per Lo Studio Degli Ecosistemi ISE , Pallanza Verbania, , Italy; Instituto de Investigaciones de Biodiversidad y Medio Ambiente INIBIOMA , Concejo Nacional de Investigaciones Cientificas y Tecnicas CONICET , , Argentina; Universidad Nacional Del Comahue, Quintral 1250, San Carlos de Bariloche, R8400FRF, , Argentina Lakes are ideal sites to study environmental changes since they preserve climatic, anthropogenic, and volcanic signals in their sediments. Brazo Blest is one of the most important ramifications of Lake Nahuel Huapi and it is an interesting site to study climatic variations as it receives direct discharge of heavy suspended sediments loads from Tronador Glacier through the Frias River, as a result of the abrasion of the bedrock and runoff from the surrounding Valdivian Forest. A short sediment core from Brazo Blest was analyzed for chironomid and diatom assemblages and pigments in order to reconstruct environmental changes during the last 100 years in the basin under study. This multiproxy study also included geochemical and physical analyses and reveals changes in the productivity of the lake over time, showing a shift in the 1950s from autochthonous to allochthonous organic matter. This modification is related to the increase of precipitation and the consequent fluvial runoff from two catchments, Frias River and the Blest Cantaros basin together with the effects ofrising temperatures, which affected Tronador Glacier. Further, it allows us to link volcanic eruptions to a decrease in species richness and number of chironomids and diatoms, as a consequence of reduced light intensities and food availability induced by the high content of suspended sediments in the water column. This study highlights the effectiveness of multiproxy analyses to reconstruct environmental changes. 53 Published version http //www.scopus.com/inward/record.url eid=2 s2.0 84961588436 partnerID=q2rCbXpz Articolo in rivista Asociacion Paleontologica Argentina 1851 8044 Ameghiniana En linea Ameghiniana En linea Ameghiniana En linea Ameghiniana. En linea andrea.lami LAMI ANDREA |
