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dc.contributor.authorHernández, Armand
dc.contributor.authorBao, Roberto
dc.contributor.authorGiralt, Santiago
dc.contributor.authorBarker, Philip
dc.contributor.authorLeng, Melanie
dc.contributor.authorSloane, Hilary
dc.contributor.authorSáez, Alberto
dc.date.accessioned2024-03-22T17:34:20Z
dc.date.available2024-03-22T17:34:20Z
dc.date.issued2010-05-19
dc.identifier.citationArmand Hernández, Roberto Bao, Santiago Giralt, Philip A. Barker, Melanie J. Leng, Hilary J. Sloane, Alberto Sáez, Biogeochemical processes controlling oxygen and carbon isotopes of diatom silica in Late Glacial to Holocene lacustrine rhythmites, Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 299, Issues 3–4, 2011, Pages 413-425, ISSN 0031-0182, https://doi.org/10.1016/j.palaeo.2010.11.020. (https://www.sciencedirect.com/science/article/pii/S0031018210006966)es_ES
dc.identifier.issn0031-0182
dc.identifier.urihttp://hdl.handle.net/2183/35967
dc.descriptionPreprint version of the article.es_ES
dc.description.abstract[Abstract] Biogeochemical cycles and sedimentary records in lakes are related to climate controls on hydrology and catchment processes. Changes in the isotopic composition of the diatom frustules (δ18Odiatom and δ13Cdiatom) in lacustrine sediments can be used to reconstruct palaeoclimatic and palaeoenvironmental changes. The Lago Chungará (Andean Altiplano, 18°15′S, 69°10′W, 4520masl) diatomaceous laminated sediments are made up of white and green multiannual rhythmites. White laminae were formed during short-term diatom super-blooms, and are composed almost exclusively of large-sized Cyclostephanos andinus. These diatoms bloom during mixing events when recycled nutrients from the bottom waters are brought to the surface and/or when nutrients are introduced from the catchment during periods of strong runoff. Conversely, the green laminae are thought to have been deposited over several years and are composed of a mixture of diatoms (mainly smaller valves of C. andinus and Discostella stelligera) and organic matter. These green laminae reflect the lake's hydrological recovery from a status favouring the diatom super-blooms (white laminae) towards baseline conditions. δ18Odiatom and δ13Cdiatom from 11,990 to 11,530cal years BP allow us to reconstruct shifts in the precipitation/evaporation ratio and changes in the lake water dissolved carbon concentration, respectively. δ18Odiatom values indicate that white laminae formation occurred mainly during low lake level stages, whereas green laminae formation generally occurred during high lake level stages. The isotope and chronostratigraphical data together suggest that white laminae deposition is caused by extraordinary environmental events. El Niño-Southern Oscillation and changes in solar activity are the most likely climate forcing mechanisms that could trigger such events, favouring hydrological changes at interannual-to-decadal scale. This study demonstrates the potential for laminated lake sediments to document extreme pluriannual events.es_ES
dc.description.sponsorshipThe Spanish Ministry of Science and Innovation funded the research at Lago Chungará through the projects ANDESTER (BTE2001-3225), Complementary Action (BTE2001-5257-E), LAVOLTER (CGL2004-00683/BTE), GEOBILA (CGL2007-60932/BTE) and CONSOLIDER-Ingenio 2010 GRACCIE (CSD2007-00067). A. Hernández have benefited from a FPI grant from The Spanish Ministry of Science and Innovation. The Limological Research Center (USA) provided the technology and expertise to retrieve the cores. We are grateful to CONAF (Chile) for the facilities provided in Parque Nacional Lauca. The NIGL (UK) funded the isotope analyses. Chris P. Kendrick is thanked for conducting the carbon isotope measurements. We also wish to thank Juan J. Pueyo for valuable discussions on the manuscript and Alice Chang for her insight on the implications of self-sedimentation processes in the formation of the laminated sediments.es_ES
dc.language.isoenges_ES
dc.publisherElsevieres_ES
dc.relationinfo:eu-repo/grantAgreement/MICYT/Plan Nacional de I+D+i 2000-2003/BTE2001-3225/ES/es_ES
dc.relationinfo:eu-repo/grantAgreement/MICYT/Plan Nacional de I+D+i 2004-2007/CGL2004-00683/ES/FENOMENOS EXTREMOS EN EL REGISTRO SEDIMENTARIO DE LAGOS EN CONTEXTO VOLCANICO-HIDROTERMAL ACTIVO/es_ES
dc.relationinfo:eu-repo/grantAgreement/MEC/Plan Nacional de I+D+i 2004-2007/CGL2007-60932/ES/RECONSTRUCCION PALEOCLIMATICA DE ALTA RESOLUCION DESDE EL ULTIMO MAXIMO GLACIAR BASADA EN INDICADORES GEOQUIMICOS Y BIOLOGICOS DE LAGOS ANDINOS Y DEL OCEANO PACIFICO/es_ES
dc.relationinfo:eu-repo/grantAgreement/MEC/Plan Nacional de I+D+i 2004-2007/CSD2007-00067/ES/MULTIDISCIPLINARY RESEARCH CONSORTIUM ON GRADUAL AND ABRUPT CLIMATE CHANGES, AND THEIR IMPACTS ON THE ENVIRONMENT (GRACCIE)/es_ES
dc.relation.urihttps://doi.org/10.1016/j.palaeo.2010.11.020es_ES
dc.subjectOxygen isotopeses_ES
dc.subjectCarbon isotopeses_ES
dc.subjectDiatomses_ES
dc.subjectLacustrine sedimentses_ES
dc.subjectAndean Altiplanoes_ES
dc.subjectENSOes_ES
dc.titleBiogeochemical Processes Controlling Oxygen and Carbon Isotopes of Diatom Silica in Late Glacial to Holocene Lacustrine Rhythmiteses_ES
dc.typeinfo:eu-repo/semantics/preprintes_ES
dc.rights.accessinfo:eu-repo/semantics/openAccesses_ES
UDC.journalTitlePalaeogeography, Palaeoclimatology, Palaeoecologyes_ES
UDC.volume299es_ES
UDC.issue3–4 (15 January 2011)es_ES
UDC.startPage413es_ES
UDC.endPage425es_ES
dc.identifier.doi10.1016/j.palaeo.2010.11.020


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