Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina

Autores
Hassan, Gabriela Susana
Año de publicación
2013
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Diatoms recovered from shallow Lake Lonkoy sediment core in southern Pampas, Argentina, were studied in order to assess past environmental conditions. A total of 47 samples were selected from a 1.42-m long core that spans the last 4840 cal. years. Diatoms were extracted by chemical cleaning and studied under light and scanning electron microscopy. A total of 89 diatom taxa were recorded, including 36 taxa that reached>2% relative abundance and were used in statistical analyses. A cluster analysis allowed five significant diatom association zones (DAZ) to be defined. DAZ I (142–92 cm) was dominated by Cyclotella meneghiniana Kützing, Cocconeis placentula Ehrenberg and Nitzschia hustedtiana Salah, and a low abundance of aerophilic taxa, indicating brackish water conditions probably related to the Holocene sea-level high stand. DAZ II (90–48.5 cm) was dominated by C. meneghiniana and Aulacoseira granulata (Ehrenberg) Simonsen, representing a period of high nutrient loading and turbid conditions in the lake, associated with higher water levels and lower salinities than the environmental conditions in DAZ I. The upper 50 cm of the core (DAZ III to V) showed an increase in the dominance of brackish epiphytic and hypereutrophic benthic taxa, indicating an increase in nutrient concentrations associated with agricultural human impacts in the basin. Overall, diatoms allowed major paleoenvironmental changes to be inferred for the lake during the Holocene.
Fil: Hassan, Gabriela Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina
Materia
Shallow Lake
Paleoecology
Holocene
Southern Pampas
Argentina
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/25907
Acceder
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network_acronym_str CONICETDig
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network_name_str CONICET Digital (CONICET)
spelling Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, ArgentinaHassan, Gabriela SusanaShallow LakePaleoecologyHoloceneSouthern PampasArgentinahttps://purl.org/becyt/ford/1.5https://purl.org/becyt/ford/1Diatoms recovered from shallow Lake Lonkoy sediment core in southern Pampas, Argentina, were studied in order to assess past environmental conditions. A total of 47 samples were selected from a 1.42-m long core that spans the last 4840 cal. years. Diatoms were extracted by chemical cleaning and studied under light and scanning electron microscopy. A total of 89 diatom taxa were recorded, including 36 taxa that reached>2% relative abundance and were used in statistical analyses. A cluster analysis allowed five significant diatom association zones (DAZ) to be defined. DAZ I (142–92 cm) was dominated by Cyclotella meneghiniana Kützing, Cocconeis placentula Ehrenberg and Nitzschia hustedtiana Salah, and a low abundance of aerophilic taxa, indicating brackish water conditions probably related to the Holocene sea-level high stand. DAZ II (90–48.5 cm) was dominated by C. meneghiniana and Aulacoseira granulata (Ehrenberg) Simonsen, representing a period of high nutrient loading and turbid conditions in the lake, associated with higher water levels and lower salinities than the environmental conditions in DAZ I. The upper 50 cm of the core (DAZ III to V) showed an increase in the dominance of brackish epiphytic and hypereutrophic benthic taxa, indicating an increase in nutrient concentrations associated with agricultural human impacts in the basin. Overall, diatoms allowed major paleoenvironmental changes to be inferred for the lake during the Holocene.Fil: Hassan, Gabriela Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaBiopress Limited2013-12info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/25907Hassan, Gabriela Susana; Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina; Biopress Limited; Diatom Research; 28; 4; 12-2013; 473-4860269-249XCONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1080/0269249X.2013.851118info:eu-repo/semantics/altIdentifier/url/http://www.tandfonline.com/doi/abs/10.1080/0269249X.2013.851118info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-03T10:10:36Zoai:ri.conicet.gov.ar:11336/25907instacron: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:34982025-09-03 10:10:37.013CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina
title Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina
spellingShingle Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina
Hassan, Gabriela Susana
Shallow Lake
Paleoecology
Holocene
Southern Pampas
Argentina
title_short Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina
title_full Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina
title_fullStr Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina
title_full_unstemmed Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina
title_sort Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina
dc.creator.none.fl_str_mv Hassan, Gabriela Susana
author Hassan, Gabriela Susana
author_facet Hassan, Gabriela Susana
author_role author
dc.subject.none.fl_str_mv Shallow Lake
Paleoecology
Holocene
Southern Pampas
Argentina
topic Shallow Lake
Paleoecology
Holocene
Southern Pampas
Argentina
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv Diatoms recovered from shallow Lake Lonkoy sediment core in southern Pampas, Argentina, were studied in order to assess past environmental conditions. A total of 47 samples were selected from a 1.42-m long core that spans the last 4840 cal. years. Diatoms were extracted by chemical cleaning and studied under light and scanning electron microscopy. A total of 89 diatom taxa were recorded, including 36 taxa that reached>2% relative abundance and were used in statistical analyses. A cluster analysis allowed five significant diatom association zones (DAZ) to be defined. DAZ I (142–92 cm) was dominated by Cyclotella meneghiniana Kützing, Cocconeis placentula Ehrenberg and Nitzschia hustedtiana Salah, and a low abundance of aerophilic taxa, indicating brackish water conditions probably related to the Holocene sea-level high stand. DAZ II (90–48.5 cm) was dominated by C. meneghiniana and Aulacoseira granulata (Ehrenberg) Simonsen, representing a period of high nutrient loading and turbid conditions in the lake, associated with higher water levels and lower salinities than the environmental conditions in DAZ I. The upper 50 cm of the core (DAZ III to V) showed an increase in the dominance of brackish epiphytic and hypereutrophic benthic taxa, indicating an increase in nutrient concentrations associated with agricultural human impacts in the basin. Overall, diatoms allowed major paleoenvironmental changes to be inferred for the lake during the Holocene.
Fil: Hassan, Gabriela Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencia Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina
description Diatoms recovered from shallow Lake Lonkoy sediment core in southern Pampas, Argentina, were studied in order to assess past environmental conditions. A total of 47 samples were selected from a 1.42-m long core that spans the last 4840 cal. years. Diatoms were extracted by chemical cleaning and studied under light and scanning electron microscopy. A total of 89 diatom taxa were recorded, including 36 taxa that reached>2% relative abundance and were used in statistical analyses. A cluster analysis allowed five significant diatom association zones (DAZ) to be defined. DAZ I (142–92 cm) was dominated by Cyclotella meneghiniana Kützing, Cocconeis placentula Ehrenberg and Nitzschia hustedtiana Salah, and a low abundance of aerophilic taxa, indicating brackish water conditions probably related to the Holocene sea-level high stand. DAZ II (90–48.5 cm) was dominated by C. meneghiniana and Aulacoseira granulata (Ehrenberg) Simonsen, representing a period of high nutrient loading and turbid conditions in the lake, associated with higher water levels and lower salinities than the environmental conditions in DAZ I. The upper 50 cm of the core (DAZ III to V) showed an increase in the dominance of brackish epiphytic and hypereutrophic benthic taxa, indicating an increase in nutrient concentrations associated with agricultural human impacts in the basin. Overall, diatoms allowed major paleoenvironmental changes to be inferred for the lake during the Holocene.
publishDate 2013
dc.date.none.fl_str_mv 2013-12
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/25907
Hassan, Gabriela Susana; Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina; Biopress Limited; Diatom Research; 28; 4; 12-2013; 473-486
0269-249X
CONICET Digital
CONICET
url http://hdl.handle.net/11336/25907
identifier_str_mv Hassan, Gabriela Susana; Diatom-based reconstruction of Middle to Late Holocene paleoenvironments in Lake Lonkoy, southern Pampas, Argentina; Biopress Limited; Diatom Research; 28; 4; 12-2013; 473-486
0269-249X
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1080/0269249X.2013.851118
info:eu-repo/semantics/altIdentifier/url/http://www.tandfonline.com/doi/abs/10.1080/0269249X.2013.851118
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
dc.publisher.none.fl_str_mv Biopress Limited
publisher.none.fl_str_mv Biopress Limited
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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score 13.13397

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