Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 years

Macrofossil analysis of a composite 19m long sediment core from Rano Raraku Lake (Easter Island) wasrelated to litho-sedimentary and geochemical features of the sediment. Strong stratigraphical patterns are shown by indirect gradient analyses of the data. The good correspondence between the stratigr...

ver descrição completa

Detalhes bibliográficos
Autores: Cañellas-Boltà, Núria, Rull, Valentí, Sáez, Alberto, Margalef, Olga, Giralt, Santiago, Pueyo Mur, Juan José, Birks, Hilary H., Birks, H. J. B., Pla-Rabes, Sergi
Tipo de documento: artigo
Data de publicação:2012
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositório:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/96628
Acesso em linha:http://hdl.handle.net/10261/96628
Access Level:Acceso aberto
Palavra-chave:Geochemistry
Macrofossils
Taphonomy
Sedimentary facies
Last glacial period
Holocene
Palaeolimnology
Rapa Nui
id ES_d76a11fe6f8d2ededb18687b908b213f
oai_identifier_str oai:digital.csic.es:10261/96628
network_acronym_str ES
network_name_str España
repository_id_str
spelling Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 yearsCañellas-Boltà, NúriaRull, ValentíSáez, AlbertoMargalef, OlgaGiralt, SantiagoPueyo Mur, Juan JoséBirks, Hilary H.Birks, H. J. B.Pla-Rabes, SergiGeochemistryMacrofossilsTaphonomySedimentary faciesLast glacial periodHolocenePalaeolimnologyRapa NuiMacrofossil analysis of a composite 19m long sediment core from Rano Raraku Lake (Easter Island) wasrelated to litho-sedimentary and geochemical features of the sediment. Strong stratigraphical patterns are shown by indirect gradient analyses of the data. The good correspondence between the stratigraphical patterns derived from macrofossil (Correspondence Analysis) and sedimentary and geochemical data (Principal Component Analysis) shows that macrofossil associations provide sound palaeolimnological information in conjunction with sedimentary data. The main taphonomic factors influencing the macrofossil assemblages are run-off from the catchment, the littoral plant belt, and the depositional environment within the basin. Five main stages during the last 34,000 calibrated years BP (calyrBP) are characterised from the lithological, geochemical, and macrofossil data. From 34 to 14.6calkyrBP (last glacial period) the sediments were largely derived from the catchment, indicating a high energy lake environment with much erosion and run-off bringing abundant plant trichomes, lichens, and mosses into the centre of Raraku Lake. During the early Holocene the infilling of the lake basin and warmer conditions favoured the growth of a littoral plant belt that obstructed terrigenous input. Cladoceran remains and Solanaceae seeds are indicative of reduced run-off and higher values of N and organic C indicate increased aquatic and catchment productivity. From 8.7 to 4.5calkyrBP a swamp occupied the entire basin. The increase of Cyperaceae seeds reflects this swamp development and, with oribatid mites and coleopteran remains, indicates a peaty environment and more anoxic conditions in Raraku. At around 4.5calkyrBP dry conditions prevented peat growth and there is a sedimentary hiatus. About 800calyrBP, peat deposition resumed. Finally, in the last few centuries, a small lake formed within the surrounding swamp. Evidence of human activity is recorded in these uppermost sediments. © 2011 Elsevier Ltd.This research was funded by the Spanish Ministry of Science and Education through the projects LAVOLTER (CGL2004-00683/BTE), GEOBILA (CGL2007-60932/BTE) and CONSOLIDER GRACCIE (CSD2007-00067) and an undergraduate grant (BES-2008-002938 to N. Cañellas-Boltà).Peer ReviewedElsevier20122014info:eu-repo/semantics/articlehttp://purl.org/coar/resource_type/c_6501http://hdl.handle.net/10261/96628reponame:DIGITAL.CSIC. Repositorio Institucional del CSICinstname:Consejo Superior de Investigaciones Científicas (CSIC)Ingléshttp://dx.doi.org/10.1016/j.quascirev.2011.12.013info:eu-repo/semantics/openAccessoai:digital.csic.es:10261/966282026-05-22T06:33:51Z
dc.title.none.fl_str_mv Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 years
title Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 years
spellingShingle Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 years
Cañellas-Boltà, Núria
Geochemistry
Macrofossils
Taphonomy
Sedimentary facies
Last glacial period
Holocene
Palaeolimnology
Rapa Nui
title_short Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 years
title_full Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 years
title_fullStr Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 years
title_full_unstemmed Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 years
title_sort Macrofossils in Raraku Lake (Easter Island) integrated with sedimentary and geochemical records: Towards a palaeoecological synthesis for the last 34,000 years
dc.creator.none.fl_str_mv Cañellas-Boltà, Núria
Rull, Valentí
Sáez, Alberto
Margalef, Olga
Giralt, Santiago
Pueyo Mur, Juan José
Birks, Hilary H.
Birks, H. J. B.
Pla-Rabes, Sergi
author Cañellas-Boltà, Núria
author_facet Cañellas-Boltà, Núria
Rull, Valentí
Sáez, Alberto
Margalef, Olga
Giralt, Santiago
Pueyo Mur, Juan José
Birks, Hilary H.
Birks, H. J. B.
Pla-Rabes, Sergi
author_role author
author2 Rull, Valentí
Sáez, Alberto
Margalef, Olga
Giralt, Santiago
Pueyo Mur, Juan José
Birks, Hilary H.
Birks, H. J. B.
Pla-Rabes, Sergi
author2_role author
author
author
author
author
author
author
author
dc.subject.none.fl_str_mv Geochemistry
Macrofossils
Taphonomy
Sedimentary facies
Last glacial period
Holocene
Palaeolimnology
Rapa Nui
topic Geochemistry
Macrofossils
Taphonomy
Sedimentary facies
Last glacial period
Holocene
Palaeolimnology
Rapa Nui
description Macrofossil analysis of a composite 19m long sediment core from Rano Raraku Lake (Easter Island) wasrelated to litho-sedimentary and geochemical features of the sediment. Strong stratigraphical patterns are shown by indirect gradient analyses of the data. The good correspondence between the stratigraphical patterns derived from macrofossil (Correspondence Analysis) and sedimentary and geochemical data (Principal Component Analysis) shows that macrofossil associations provide sound palaeolimnological information in conjunction with sedimentary data. The main taphonomic factors influencing the macrofossil assemblages are run-off from the catchment, the littoral plant belt, and the depositional environment within the basin. Five main stages during the last 34,000 calibrated years BP (calyrBP) are characterised from the lithological, geochemical, and macrofossil data. From 34 to 14.6calkyrBP (last glacial period) the sediments were largely derived from the catchment, indicating a high energy lake environment with much erosion and run-off bringing abundant plant trichomes, lichens, and mosses into the centre of Raraku Lake. During the early Holocene the infilling of the lake basin and warmer conditions favoured the growth of a littoral plant belt that obstructed terrigenous input. Cladoceran remains and Solanaceae seeds are indicative of reduced run-off and higher values of N and organic C indicate increased aquatic and catchment productivity. From 8.7 to 4.5calkyrBP a swamp occupied the entire basin. The increase of Cyperaceae seeds reflects this swamp development and, with oribatid mites and coleopteran remains, indicates a peaty environment and more anoxic conditions in Raraku. At around 4.5calkyrBP dry conditions prevented peat growth and there is a sedimentary hiatus. About 800calyrBP, peat deposition resumed. Finally, in the last few centuries, a small lake formed within the surrounding swamp. Evidence of human activity is recorded in these uppermost sediments. © 2011 Elsevier Ltd.
publishDate 2012
dc.date.none.fl_str_mv 2012
2014
dc.type.none.fl_str_mv info:eu-repo/semantics/article
http://purl.org/coar/resource_type/c_6501
format article
dc.identifier.none.fl_str_mv http://hdl.handle.net/10261/96628
url http://hdl.handle.net/10261/96628
dc.language.none.fl_str_mv Inglés
language_invalid_str_mv Inglés
dc.relation.none.fl_str_mv http://dx.doi.org/10.1016/j.quascirev.2011.12.013
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.publisher.none.fl_str_mv Elsevier
publisher.none.fl_str_mv Elsevier
dc.source.none.fl_str_mv reponame:DIGITAL.CSIC. Repositorio Institucional del CSIC
instname:Consejo Superior de Investigaciones Científicas (CSIC)
instname_str Consejo Superior de Investigaciones Científicas (CSIC)
reponame_str DIGITAL.CSIC. Repositorio Institucional del CSIC
collection DIGITAL.CSIC. Repositorio Institucional del CSIC
repository.name.fl_str_mv
repository.mail.fl_str_mv
_version_ 1869421001253584896
score 15,812455

Registros relacionados