Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments

Autores
Vignoni, Paula; Tjallingii, Rik; Cordoba, Francisco Elizalde; Plessen, Birgit; Torres, Gonzalo Román; Lupo, Liliana Concepcion; Nowaczyk, Norbert; Brauer, Achim
Año de publicación
2020
Idioma
inglés
Tipo de recurso
documento de conferencia
Estado
versión publicada
Descripción
Due to the meridional extension and prominent orography, the Central Andes of NW Argentina act as a topographic barrier to the moisture-bearing easterly winds. This result in contrasting climate conditions and a steep E-W rainfall gradient with high precipitation on the eastern flanks and increasing aridity westwards into the Puna plateau. Laguna Comedero is a shallow lake located in the subtropical forest of the Yungas in the eastern flank of the Argentine Eastern Cordillera (24°06´54.7" S - 65°29´7.2" W, 2,035 m a.s.l.). About 80% of the total annual precipitation (~1300 mm, Los Nogales station 1958-1989) occurs between November and March, controlled by the dynamics of the South American Monsoon System (SAMS). This region is considered sensitive to shifts in the SAMS, as well as the superposition of other large-scale phenomena (e.g. El Niño Southern Oscillation, Pacific Decadal Oscillation) but the timing and extent of precipitation changes prior to the instrumental period in this area are still largely unknown. Here we present a combination of XRF core scanning, CN elemental analyses and stable isotopes of an 11 m-long sediment record from this lake for reconstructing the regional late Holocene climate history in this region of South America. Our results reveal a prominent shift in sedimentation, from detrital brown event-triggered silt and clay deposition and sandy intervals in the lower part of the core to an alternation of gray clastic and black organic-rich intervals in the upper 3.5 m. Below this shift in sedimentation, low TOC values (mean 0.34%) and high values ofelements indicative of detrital sediments (e.g. Ti) suggest a dominance of catchment erosion processes. High TOC values of up to 20.5% in the organic-rich intervals in the uppermost 3.5 m likely reflect substantial terrestrial organic matter influx as suggested by C/N atomic ratios around 17. δ13COM values in these intervals (-28.8 to -22.2?) reflect the contribution of the Yungas forest (-27.9 to -27.2?) surrounding the lake, dominated by Alnus acuminata, Polypepis australis, Podocarpus parlatorei, among other subtropical tree species. Alnus forest is related to >1000 mm/yr rainfalls. The pronounced alternation of organic-rich and detrital sediments in the upper 3.5 m suggest highly variable lake conditions that might be either influenced by climate and/or catchment changes and is the focus of further investigations. Preliminary dating suggests that the increase in organic matter deposition in the lake occurred at the beginning of the last millennium (ca. AD 1,000). A more detailed chronological framework is in progress including a paleomagnetic reconstruction for this area.
Fil: Vignoni, Paula. German Research Centre for Geosciences; Alemania. Universitat Potsdam; Alemania
Fil: Tjallingii, Rik. German Research Centre for Geosciences; Alemania
Fil: Cordoba, Francisco Elizalde. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina
Fil: Plessen, Birgit. German Research Centre for Geosciences; Alemania
Fil: Torres, Gonzalo Román. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina
Fil: Lupo, Liliana Concepcion. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina
Fil: Nowaczyk, Norbert. German Research Centre for Geosciences; Alemania
Fil: Brauer, Achim. German Research Centre for Geosciences; Alemania
EGU General Assembly 2020
Vienna
Austria
European Geosciences Union
Materia
LAKE SEDIMENTS
PALAEOENVIRONMENTAL CHANGES
SOUTH AMERICAN MONSOON SYSTEM
NORTHWEST ARGENTINA
LATE HOLOCENE
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/156726

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network_name_str CONICET Digital (CONICET)
spelling Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sedimentsVignoni, PaulaTjallingii, RikCordoba, Francisco ElizaldePlessen, BirgitTorres, Gonzalo RománLupo, Liliana ConcepcionNowaczyk, NorbertBrauer, AchimLAKE SEDIMENTSPALAEOENVIRONMENTAL CHANGESSOUTH AMERICAN MONSOON SYSTEMNORTHWEST ARGENTINALATE HOLOCENEhttps://purl.org/becyt/ford/1.5https://purl.org/becyt/ford/1Due to the meridional extension and prominent orography, the Central Andes of NW Argentina act as a topographic barrier to the moisture-bearing easterly winds. This result in contrasting climate conditions and a steep E-W rainfall gradient with high precipitation on the eastern flanks and increasing aridity westwards into the Puna plateau. Laguna Comedero is a shallow lake located in the subtropical forest of the Yungas in the eastern flank of the Argentine Eastern Cordillera (24°06´54.7" S - 65°29´7.2" W, 2,035 m a.s.l.). About 80% of the total annual precipitation (~1300 mm, Los Nogales station 1958-1989) occurs between November and March, controlled by the dynamics of the South American Monsoon System (SAMS). This region is considered sensitive to shifts in the SAMS, as well as the superposition of other large-scale phenomena (e.g. El Niño Southern Oscillation, Pacific Decadal Oscillation) but the timing and extent of precipitation changes prior to the instrumental period in this area are still largely unknown. Here we present a combination of XRF core scanning, CN elemental analyses and stable isotopes of an 11 m-long sediment record from this lake for reconstructing the regional late Holocene climate history in this region of South America. Our results reveal a prominent shift in sedimentation, from detrital brown event-triggered silt and clay deposition and sandy intervals in the lower part of the core to an alternation of gray clastic and black organic-rich intervals in the upper 3.5 m. Below this shift in sedimentation, low TOC values (mean 0.34%) and high values ofelements indicative of detrital sediments (e.g. Ti) suggest a dominance of catchment erosion processes. High TOC values of up to 20.5% in the organic-rich intervals in the uppermost 3.5 m likely reflect substantial terrestrial organic matter influx as suggested by C/N atomic ratios around 17. δ13COM values in these intervals (-28.8 to -22.2?) reflect the contribution of the Yungas forest (-27.9 to -27.2?) surrounding the lake, dominated by Alnus acuminata, Polypepis australis, Podocarpus parlatorei, among other subtropical tree species. Alnus forest is related to >1000 mm/yr rainfalls. The pronounced alternation of organic-rich and detrital sediments in the upper 3.5 m suggest highly variable lake conditions that might be either influenced by climate and/or catchment changes and is the focus of further investigations. Preliminary dating suggests that the increase in organic matter deposition in the lake occurred at the beginning of the last millennium (ca. AD 1,000). A more detailed chronological framework is in progress including a paleomagnetic reconstruction for this area.Fil: Vignoni, Paula. German Research Centre for Geosciences; Alemania. Universitat Potsdam; AlemaniaFil: Tjallingii, Rik. German Research Centre for Geosciences; AlemaniaFil: Cordoba, Francisco Elizalde. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Plessen, Birgit. German Research Centre for Geosciences; AlemaniaFil: Torres, Gonzalo Román. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Lupo, Liliana Concepcion. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Nowaczyk, Norbert. German Research Centre for Geosciences; AlemaniaFil: Brauer, Achim. German Research Centre for Geosciences; AlemaniaEGU General Assembly 2020ViennaAustriaEuropean Geosciences UnionEuropean Geosciences Union2020info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/conferenceObjectCongresoBookhttp://purl.org/coar/resource_type/c_5794info:ar-repo/semantics/documentoDeConferenciaapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/156726Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments; EGU General Assembly 2020; Vienna; Austria; 2020; 1-2CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.5194/egusphere-egu2020-18601Internacionalinfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:40:27Zoai:ri.conicet.gov.ar:11336/156726instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 10:40:28.171CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments
title Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments
spellingShingle Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments
Vignoni, Paula
LAKE SEDIMENTS
PALAEOENVIRONMENTAL CHANGES
SOUTH AMERICAN MONSOON SYSTEM
NORTHWEST ARGENTINA
LATE HOLOCENE
title_short Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments
title_full Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments
title_fullStr Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments
title_full_unstemmed Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments
title_sort Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments
dc.creator.none.fl_str_mv Vignoni, Paula
Tjallingii, Rik
Cordoba, Francisco Elizalde
Plessen, Birgit
Torres, Gonzalo Román
Lupo, Liliana Concepcion
Nowaczyk, Norbert
Brauer, Achim
author Vignoni, Paula
author_facet Vignoni, Paula
Tjallingii, Rik
Cordoba, Francisco Elizalde
Plessen, Birgit
Torres, Gonzalo Román
Lupo, Liliana Concepcion
Nowaczyk, Norbert
Brauer, Achim
author_role author
author2 Tjallingii, Rik
Cordoba, Francisco Elizalde
Plessen, Birgit
Torres, Gonzalo Román
Lupo, Liliana Concepcion
Nowaczyk, Norbert
Brauer, Achim
author2_role author
author
author
author
author
author
author
dc.subject.none.fl_str_mv LAKE SEDIMENTS
PALAEOENVIRONMENTAL CHANGES
SOUTH AMERICAN MONSOON SYSTEM
NORTHWEST ARGENTINA
LATE HOLOCENE
topic LAKE SEDIMENTS
PALAEOENVIRONMENTAL CHANGES
SOUTH AMERICAN MONSOON SYSTEM
NORTHWEST ARGENTINA
LATE HOLOCENE
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv Due to the meridional extension and prominent orography, the Central Andes of NW Argentina act as a topographic barrier to the moisture-bearing easterly winds. This result in contrasting climate conditions and a steep E-W rainfall gradient with high precipitation on the eastern flanks and increasing aridity westwards into the Puna plateau. Laguna Comedero is a shallow lake located in the subtropical forest of the Yungas in the eastern flank of the Argentine Eastern Cordillera (24°06´54.7" S - 65°29´7.2" W, 2,035 m a.s.l.). About 80% of the total annual precipitation (~1300 mm, Los Nogales station 1958-1989) occurs between November and March, controlled by the dynamics of the South American Monsoon System (SAMS). This region is considered sensitive to shifts in the SAMS, as well as the superposition of other large-scale phenomena (e.g. El Niño Southern Oscillation, Pacific Decadal Oscillation) but the timing and extent of precipitation changes prior to the instrumental period in this area are still largely unknown. Here we present a combination of XRF core scanning, CN elemental analyses and stable isotopes of an 11 m-long sediment record from this lake for reconstructing the regional late Holocene climate history in this region of South America. Our results reveal a prominent shift in sedimentation, from detrital brown event-triggered silt and clay deposition and sandy intervals in the lower part of the core to an alternation of gray clastic and black organic-rich intervals in the upper 3.5 m. Below this shift in sedimentation, low TOC values (mean 0.34%) and high values ofelements indicative of detrital sediments (e.g. Ti) suggest a dominance of catchment erosion processes. High TOC values of up to 20.5% in the organic-rich intervals in the uppermost 3.5 m likely reflect substantial terrestrial organic matter influx as suggested by C/N atomic ratios around 17. δ13COM values in these intervals (-28.8 to -22.2?) reflect the contribution of the Yungas forest (-27.9 to -27.2?) surrounding the lake, dominated by Alnus acuminata, Polypepis australis, Podocarpus parlatorei, among other subtropical tree species. Alnus forest is related to >1000 mm/yr rainfalls. The pronounced alternation of organic-rich and detrital sediments in the upper 3.5 m suggest highly variable lake conditions that might be either influenced by climate and/or catchment changes and is the focus of further investigations. Preliminary dating suggests that the increase in organic matter deposition in the lake occurred at the beginning of the last millennium (ca. AD 1,000). A more detailed chronological framework is in progress including a paleomagnetic reconstruction for this area.
Fil: Vignoni, Paula. German Research Centre for Geosciences; Alemania. Universitat Potsdam; Alemania
Fil: Tjallingii, Rik. German Research Centre for Geosciences; Alemania
Fil: Cordoba, Francisco Elizalde. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina
Fil: Plessen, Birgit. German Research Centre for Geosciences; Alemania
Fil: Torres, Gonzalo Román. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina
Fil: Lupo, Liliana Concepcion. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina
Fil: Nowaczyk, Norbert. German Research Centre for Geosciences; Alemania
Fil: Brauer, Achim. German Research Centre for Geosciences; Alemania
EGU General Assembly 2020
Vienna
Austria
European Geosciences Union
description Due to the meridional extension and prominent orography, the Central Andes of NW Argentina act as a topographic barrier to the moisture-bearing easterly winds. This result in contrasting climate conditions and a steep E-W rainfall gradient with high precipitation on the eastern flanks and increasing aridity westwards into the Puna plateau. Laguna Comedero is a shallow lake located in the subtropical forest of the Yungas in the eastern flank of the Argentine Eastern Cordillera (24°06´54.7" S - 65°29´7.2" W, 2,035 m a.s.l.). About 80% of the total annual precipitation (~1300 mm, Los Nogales station 1958-1989) occurs between November and March, controlled by the dynamics of the South American Monsoon System (SAMS). This region is considered sensitive to shifts in the SAMS, as well as the superposition of other large-scale phenomena (e.g. El Niño Southern Oscillation, Pacific Decadal Oscillation) but the timing and extent of precipitation changes prior to the instrumental period in this area are still largely unknown. Here we present a combination of XRF core scanning, CN elemental analyses and stable isotopes of an 11 m-long sediment record from this lake for reconstructing the regional late Holocene climate history in this region of South America. Our results reveal a prominent shift in sedimentation, from detrital brown event-triggered silt and clay deposition and sandy intervals in the lower part of the core to an alternation of gray clastic and black organic-rich intervals in the upper 3.5 m. Below this shift in sedimentation, low TOC values (mean 0.34%) and high values ofelements indicative of detrital sediments (e.g. Ti) suggest a dominance of catchment erosion processes. High TOC values of up to 20.5% in the organic-rich intervals in the uppermost 3.5 m likely reflect substantial terrestrial organic matter influx as suggested by C/N atomic ratios around 17. δ13COM values in these intervals (-28.8 to -22.2?) reflect the contribution of the Yungas forest (-27.9 to -27.2?) surrounding the lake, dominated by Alnus acuminata, Polypepis australis, Podocarpus parlatorei, among other subtropical tree species. Alnus forest is related to >1000 mm/yr rainfalls. The pronounced alternation of organic-rich and detrital sediments in the upper 3.5 m suggest highly variable lake conditions that might be either influenced by climate and/or catchment changes and is the focus of further investigations. Preliminary dating suggests that the increase in organic matter deposition in the lake occurred at the beginning of the last millennium (ca. AD 1,000). A more detailed chronological framework is in progress including a paleomagnetic reconstruction for this area.
publishDate 2020
dc.date.none.fl_str_mv 2020
dc.type.none.fl_str_mv info:eu-repo/semantics/publishedVersion
info:eu-repo/semantics/conferenceObject
Congreso
Book
http://purl.org/coar/resource_type/c_5794
info:ar-repo/semantics/documentoDeConferencia
status_str publishedVersion
format conferenceObject
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/156726
Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments; EGU General Assembly 2020; Vienna; Austria; 2020; 1-2
CONICET Digital
CONICET
url http://hdl.handle.net/11336/156726
identifier_str_mv Past climate and environmental changes in the Central Andes of NW Argentina recorded in Laguna Comedero sediments; EGU General Assembly 2020; Vienna; Austria; 2020; 1-2
CONICET Digital
CONICET
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language eng
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https://creativecommons.org/licenses/by/2.5/ar/
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dc.coverage.none.fl_str_mv Internacional
dc.publisher.none.fl_str_mv European Geosciences Union
publisher.none.fl_str_mv European Geosciences Union
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