Paleoecologia das lagoas do Pantanal por análises multiproxy.
Global climate change influences the precipitation patterns, which can have dramatic effects on aquatic and terrestrial ecology. In order to create mitigation strategies is required a deep understanding of the mechanisms and rates of climate change. Lakes and wetlands are sentinels of environmental changes because their sediments and water columns serve as sensitive records of the climate, hydrology, and anthropogenic (human-induced) processes. The Pantanal, located in the Upper Paraguay River, is considered the largest wetland on Earth, and it performs numerous ecosystem services, has an immense biodiversity and is fundamental to global biogeochemical cycles. The environmental changes that occurred on the western border of the Pantanal during the last 19 cal kyr BP were interpreted based on the paleolimnological analysis of sedimentary cores recovered in the Negra and Cáceres lakes. The cores, show variations in the abundance, diversity, and preservation of sponge spicules, phytoliths, and geochemistry of sediments over time. In the Late Pleistocene, the Lakes Negra and Cáceres were strongly influenced by the South American Monsoon System, with intense fluvial activity during a more humid climate. The accumulation of organic carbon in the Pantanal floodplain lakes varied throughout the Late Quaternary. In the Middle Holocene, however, there were drier periods when these lakes were disconnected from the Paraguay River. High levels of organic carbon have been recorded from ~ 7.3-6 cal kyr BP. The records of δ13Corg, δ15Norg and C/N revealed that the organic matter deposited during this phase in the Gaíva, Castelo, Cáceres, and Negra lakes are the source of aquatic macrophytes. It is suggested that the increase in carbon burial in these lakes occurred in a drier climate, in which there was a decrease in the pelagic area. However, the productive coastal areas remained flooded and without the influence of the flood pulses, which were colonized by extensive mats of aquatic macrophytes. The prolonged drier climate resulted in the desiccation and subaerially exposed lake floor, causing sedimentary gaps close to the transition to the Late Holocene. The data suggest that the lakes in the Pantanal floodplain respond in a complex and sometimes indirect way to global climate change. In this sense, the dynamics of the adjacent river system must be considered when interpreting paleohydrology and vegetation patterns. The results of this study allowed new interpretations about the hydroclimatic controls of the lacustrine carbon cycling in the Pantanal wetlands.
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Language: | English |
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Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
2020
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Subjects: | Paleoecologia, Microfósseis de água doce, Espículas de esponjas, Microfósseis de plantas, Fitólitos, Geomorfologia fluvial, Mudanças climáticas, Lagoas, Quaternário Tardio, ASFA_2015::P::Palaeoecology, ASFA_2015::F::Fossils, ASFA_2015::S::Sponges, ASFA_2015::O::Organic carbon, ASFA_2015::W::Wetlands, ASFA_2015::H::Holocene, ASFA_2015::F::Freshwater lakes, ASFA_2015::C::Climatic changes, ASFA_2015::G::Geomorphology, ASFA_2015::F::Floodplains, ASFA_2015::P::Plant fossils, ASFA_2015::F::Fresh water, ASFA_2015::R::Rivers, |
Online Access: | http://hdl.handle.net/1834/41879 |
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Paleoecologia Microfósseis de água doce Espículas de esponjas Microfósseis de plantas Fitólitos Geomorfologia fluvial Mudanças climáticas Lagoas Quaternário Tardio ASFA_2015::P::Palaeoecology ASFA_2015::F::Fossils ASFA_2015::S::Sponges ASFA_2015::O::Organic carbon ASFA_2015::W::Wetlands ASFA_2015::H::Holocene ASFA_2015::F::Freshwater lakes ASFA_2015::C::Climatic changes ASFA_2015::G::Geomorphology ASFA_2015::F::Floodplains ASFA_2015::P::Plant fossils ASFA_2015::F::Fresh water ASFA_2015::R::Rivers Paleoecologia Microfósseis de água doce Espículas de esponjas Microfósseis de plantas Fitólitos Geomorfologia fluvial Mudanças climáticas Lagoas Quaternário Tardio ASFA_2015::P::Palaeoecology ASFA_2015::F::Fossils ASFA_2015::S::Sponges ASFA_2015::O::Organic carbon ASFA_2015::W::Wetlands ASFA_2015::H::Holocene ASFA_2015::F::Freshwater lakes ASFA_2015::C::Climatic changes ASFA_2015::G::Geomorphology ASFA_2015::F::Floodplains ASFA_2015::P::Plant fossils ASFA_2015::F::Fresh water ASFA_2015::R::Rivers |
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Paleoecologia Microfósseis de água doce Espículas de esponjas Microfósseis de plantas Fitólitos Geomorfologia fluvial Mudanças climáticas Lagoas Quaternário Tardio ASFA_2015::P::Palaeoecology ASFA_2015::F::Fossils ASFA_2015::S::Sponges ASFA_2015::O::Organic carbon ASFA_2015::W::Wetlands ASFA_2015::H::Holocene ASFA_2015::F::Freshwater lakes ASFA_2015::C::Climatic changes ASFA_2015::G::Geomorphology ASFA_2015::F::Floodplains ASFA_2015::P::Plant fossils ASFA_2015::F::Fresh water ASFA_2015::R::Rivers Paleoecologia Microfósseis de água doce Espículas de esponjas Microfósseis de plantas Fitólitos Geomorfologia fluvial Mudanças climáticas Lagoas Quaternário Tardio ASFA_2015::P::Palaeoecology ASFA_2015::F::Fossils ASFA_2015::S::Sponges ASFA_2015::O::Organic carbon ASFA_2015::W::Wetlands ASFA_2015::H::Holocene ASFA_2015::F::Freshwater lakes ASFA_2015::C::Climatic changes ASFA_2015::G::Geomorphology ASFA_2015::F::Floodplains ASFA_2015::P::Plant fossils ASFA_2015::F::Fresh water ASFA_2015::R::Rivers Rasbold, Giliane Gessica Paleoecologia das lagoas do Pantanal por análises multiproxy. |
description |
Global climate change influences the precipitation patterns, which can have dramatic effects on aquatic and terrestrial ecology. In order to create mitigation strategies is required a deep understanding of the mechanisms and rates of climate change. Lakes and wetlands are sentinels of environmental changes because their sediments and water columns serve as sensitive records of the climate, hydrology, and anthropogenic (human-induced) processes. The Pantanal, located in the Upper Paraguay River, is considered the largest wetland on Earth, and it performs numerous ecosystem services, has an immense biodiversity and is fundamental to global biogeochemical cycles. The environmental changes that occurred on the western border of the Pantanal during the last 19 cal kyr BP were interpreted based on the paleolimnological analysis of sedimentary cores recovered in the Negra and Cáceres lakes. The cores, show variations in the abundance, diversity, and preservation of sponge spicules, phytoliths, and geochemistry of sediments over time. In the Late Pleistocene, the Lakes Negra and Cáceres were strongly influenced by the South American Monsoon System, with intense fluvial activity during a more humid climate. The accumulation of organic carbon in the Pantanal floodplain lakes varied throughout the Late Quaternary. In the Middle Holocene, however, there were drier periods when these lakes were disconnected from the Paraguay River. High levels of organic carbon have been recorded from ~ 7.3-6 cal kyr BP. The records of δ13Corg, δ15Norg and C/N revealed that the organic matter deposited during this phase in the Gaíva, Castelo, Cáceres, and Negra lakes are the source of aquatic macrophytes. It is suggested that the increase in carbon burial in these lakes occurred in a drier climate, in which there was a decrease in the pelagic area. However, the productive coastal areas remained flooded and without the influence of the flood pulses, which were colonized by extensive mats of aquatic macrophytes. The prolonged drier climate resulted in the desiccation and subaerially exposed lake floor, causing sedimentary gaps close to the transition to the Late Holocene. The data suggest that the lakes in the Pantanal floodplain respond in a complex and sometimes indirect way to global climate change. In this sense, the dynamics of the adjacent river system must be considered when interpreting paleohydrology and vegetation patterns. The results of this study allowed new interpretations about the hydroclimatic controls of the lacustrine carbon cycling in the Pantanal wetlands. |
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Thesis/Dissertation |
topic_facet |
Paleoecologia Microfósseis de água doce Espículas de esponjas Microfósseis de plantas Fitólitos Geomorfologia fluvial Mudanças climáticas Lagoas Quaternário Tardio ASFA_2015::P::Palaeoecology ASFA_2015::F::Fossils ASFA_2015::S::Sponges ASFA_2015::O::Organic carbon ASFA_2015::W::Wetlands ASFA_2015::H::Holocene ASFA_2015::F::Freshwater lakes ASFA_2015::C::Climatic changes ASFA_2015::G::Geomorphology ASFA_2015::F::Floodplains ASFA_2015::P::Plant fossils ASFA_2015::F::Fresh water ASFA_2015::R::Rivers |
author |
Rasbold, Giliane Gessica |
author_facet |
Rasbold, Giliane Gessica |
author_sort |
Rasbold, Giliane Gessica |
title |
Paleoecologia das lagoas do Pantanal por análises multiproxy. |
title_short |
Paleoecologia das lagoas do Pantanal por análises multiproxy. |
title_full |
Paleoecologia das lagoas do Pantanal por análises multiproxy. |
title_fullStr |
Paleoecologia das lagoas do Pantanal por análises multiproxy. |
title_full_unstemmed |
Paleoecologia das lagoas do Pantanal por análises multiproxy. |
title_sort |
paleoecologia das lagoas do pantanal por análises multiproxy. |
publisher |
Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais. |
publishDate |
2020 |
url |
http://hdl.handle.net/1834/41879 |
work_keys_str_mv |
AT rasboldgilianegessica paleoecologiadaslagoasdopantanalporanalisesmultiproxy AT rasboldgilianegessica paleoecologyofpantanallakesviamultiproxyanalysis |
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1756080216599429120 |
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dig-aquadocs-1834-418792022-07-05T12:45:30Z Paleoecologia das lagoas do Pantanal por análises multiproxy. Paleoecology of Pantanal lakes via multiproxy analysis. Rasbold, Giliane Gessica Paleoecologia Microfósseis de água doce Espículas de esponjas Microfósseis de plantas Fitólitos Geomorfologia fluvial Mudanças climáticas Lagoas Quaternário Tardio ASFA_2015::P::Palaeoecology ASFA_2015::F::Fossils ASFA_2015::S::Sponges ASFA_2015::O::Organic carbon ASFA_2015::W::Wetlands ASFA_2015::H::Holocene ASFA_2015::F::Freshwater lakes ASFA_2015::C::Climatic changes ASFA_2015::G::Geomorphology ASFA_2015::F::Floodplains ASFA_2015::P::Plant fossils ASFA_2015::F::Fresh water ASFA_2015::R::Rivers Global climate change influences the precipitation patterns, which can have dramatic effects on aquatic and terrestrial ecology. In order to create mitigation strategies is required a deep understanding of the mechanisms and rates of climate change. Lakes and wetlands are sentinels of environmental changes because their sediments and water columns serve as sensitive records of the climate, hydrology, and anthropogenic (human-induced) processes. The Pantanal, located in the Upper Paraguay River, is considered the largest wetland on Earth, and it performs numerous ecosystem services, has an immense biodiversity and is fundamental to global biogeochemical cycles. The environmental changes that occurred on the western border of the Pantanal during the last 19 cal kyr BP were interpreted based on the paleolimnological analysis of sedimentary cores recovered in the Negra and Cáceres lakes. The cores, show variations in the abundance, diversity, and preservation of sponge spicules, phytoliths, and geochemistry of sediments over time. In the Late Pleistocene, the Lakes Negra and Cáceres were strongly influenced by the South American Monsoon System, with intense fluvial activity during a more humid climate. The accumulation of organic carbon in the Pantanal floodplain lakes varied throughout the Late Quaternary. In the Middle Holocene, however, there were drier periods when these lakes were disconnected from the Paraguay River. High levels of organic carbon have been recorded from ~ 7.3-6 cal kyr BP. The records of δ13Corg, δ15Norg and C/N revealed that the organic matter deposited during this phase in the Gaíva, Castelo, Cáceres, and Negra lakes are the source of aquatic macrophytes. It is suggested that the increase in carbon burial in these lakes occurred in a drier climate, in which there was a decrease in the pelagic area. However, the productive coastal areas remained flooded and without the influence of the flood pulses, which were colonized by extensive mats of aquatic macrophytes. The prolonged drier climate resulted in the desiccation and subaerially exposed lake floor, causing sedimentary gaps close to the transition to the Late Holocene. The data suggest that the lakes in the Pantanal floodplain respond in a complex and sometimes indirect way to global climate change. In this sense, the dynamics of the adjacent river system must be considered when interpreting paleohydrology and vegetation patterns. The results of this study allowed new interpretations about the hydroclimatic controls of the lacustrine carbon cycling in the Pantanal wetlands. As mudanças climáticas globais resultam em alterações nos padrões de precipitação, que podem ter efeitos dramáticos na ecologia aquática e terrestre. Para criar estratégias de mitigação de impactos é necessário um profundo entendimento dos mecanismos e taxas das mudanças climáticas. Os lagos e as áreas úmidas são considerados sentinelas das mudanças ambientais, porque seus sedimentos e colunas de água servem como registros sensíveis dos processos climáticos, hidrológicos e antropogênicos (induzidos pelo homem) da região. O Pantanal, localizado no alto rio Paraguai, é considerada a maior área úmida do planeta e desempenha inúmeros serviços ecossistêmicos, abriga uma imensa biodiversidade e é fundamental para os ciclos biogeoquímicos globais. As mudanças ambientais ocorridas na borda oeste do Pantanal durante os últimos 19 k anos AP foram interpretadas com base na análise paleolimnológica de testemunhos sedimentares recuperados nas lagoas Negra e Cáceres. Os testemunhos mostram variações na abundância, diversidade e preservação de espículas de esponja, fitólitos e geoquímica dos sedimentos ao longo do tempo. No final do Pleistoceno, as lagoas Negra e Cáceres foram influenciadas fortemente pelo Sistema de Monção Sul-Americano, com atividade fluvial intensa durante um clima mais úmido que o atual. A acumulação de carbono orgânico nas lagoas da planície de inundação do Pantanal variou ao longo do Quaternário Tardio. No Holoceno Médio, entretanto, houve períodos mais secos que o atual, em que essas lagoas foram desconectadas do rio Paraguai. Altos teores de carbono orgânico foram registrados a partir de ~7,3-6 k anos AP. Os registros de δ13Corg, δ15Norg e C/N revelaram que a matéria orgânica depositada durante essa fase nas lagoas Gaíva, Castelo, Cáceres e Negra (direcionadas em um transecto Norte-Sul) tem como fonte as macrófitas aquáticas. Sugere-se que o aumento no enterro de carbono ocorreu em um clima mais seco, no qual houve a diminuição da área pelágica dessas lagoas. No entanto, as áreas litorâneas produtivas permaneceram alagadas e sem influência dos pulsos de inundação, as quais foram colonizadas por extensos bancos de macrófitas aquáticas. O clima mais seco prolongado resultou na dessecação e exposição do fundo de alguns dessas lagoas, ocasionando hiatos sedimentares próximo à transição para o Holoceno Tardio. Os dados sugerem que as lagoas da planície de inundação do Pantanal respondem de maneira complexa e, às vezes, indireta às mudanças climáticas. Nesse sentido, a dinâmica do sistema fluvial adjacente deve ser considerada na interpretação dos padrões de paleoidrologia e vegetação. Os resultados deste estudo permitiram novas interpretações sobre os controles hidroclimáticos da ciclagem de carbono lacustre nas zonas úmidas do Pantanal. PhD 2022-03-10T13:39:16Z 2022-03-10T13:39:16Z 2020 Thesis/Dissertation http://hdl.handle.net/1834/41879 en http://nou-rau.uem.br/nou-rau/document/?code=4487 http://repositorio.uem.br:8080/jspui/handle/1/6543 109pp. Brasil Brazil Mato Grosso do Sul (Estado) Pantanal Planície de inundação Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais. |