Ana Dauner | University of Helsinki (original) (raw)
Papers by Ana Dauner
Orientador : Dr. César de Castro MartinsDissertação (mestrado) - Universidade Federal do Paraná, ... more Orientador : Dr. César de Castro MartinsDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Terra, Programa de Pós-Graduação em Sistemas Costeiros e Oceânicos. Defesa: Pontal do Paraná, 24/04/2015Inclui referênciasResumo: O objetivo desta dissertação foi avaliar a distribuição espacial e temporal, de curta escala, de hidrocarbonetos (hidrocarbonetos policíclicos aromáticos - HPAs, hidrocarbonetos alifáticos - HAs, Alquilbenzenos lineares - LABs) no material particulado em suspensão (MPS) da Baía de Guaratuba, PR, Brasil, bem como identificar as suas principais fontes e verificar como os parâmetros da coluna d'água afetam a sua distribuição. Para tanto, foram coletadas 22 amostras em três períodos distintos (04/2013, 08/2013 e 03/2014). De um modo geral, foram observados altos valores na porção mediana do estuário, relacionados a fenômenos hidrodinâmicos que contribuem para o acúmulo de matéria orgânica, gerando uma região atuante como um filtro geoquími...
Millennial-scale oscillations are known to be important in the climatic evolution of the Atlantic... more Millennial-scale oscillations are known to be important in the climatic evolution of the Atlantic basin, but which internal processes originates these oscillations are still uncertain. In this study, we investigated how the Greenland and Antarctic climates affect the SW Atlantic through basin-wide oceanographic features (such as the NADW formation and the Agulhas leakage). We reconstructed sea surface and subsurface temperatures (SST and subT) using three lipid-based biomarker proxies (UK'37, TEX86 and LDI indexes) from a sediment core (NAP 63-1) retrieved from the SW Atlantic slope (24.8°S, 44.3°W). This location permitted to evaluate the temperature oscillations of the Brazil Current without any terrigenous or upwelling-derived biases. Both TEX86-based and LDI-based estimates represent the mean annual SST, while the UK'37-based estimates represent the subT (around 30 m water depth). The periods with the most well-mixed water column were observed during intervals of cooling...
Hydrocarbons are organic geochemical markers found in biogenic organic matter, crude oil and thei... more Hydrocarbons are organic geochemical markers found in biogenic organic matter, crude oil and their by-products, and also in residues of burned fossil fuels and biomass. High levels of anthropogenic hydrocarbons, as polycyclic aromatic hydrocarbons (PAHs) may cause ecosystem and human health damage due the toxic and mutagenic effects. Guaratuba Bay is located on SW Atlantic coast, Brazil (25°52'S; 48°38'O). This region is within an Environmental Protected Area where Atlantic Forest remains relatively pristine. Guaratuba Bay also presents increased human occupation and tourism in summer period, what may contribute to anthropic impacts related to the hydrocarbon input. The main objective of this study was to evaluate the spatial distribution of aliphatic (AHs) and PAHs in a total of eleven surface sediments of Guaratuba Bay, collected in October 2010. Samples were freeze-dried, carefully homogenized with a mortar, extracted and purified. Subsequently, hydrocarbon concentrations...
A urbanizacao, agricultura, pecuaria, pesca e o turismo sao as principais atividades antropicas e... more A urbanizacao, agricultura, pecuaria, pesca e o turismo sao as principais atividades antropicas exercidas na Baia de Guaratuba, localizada na regiao Sul do Brasil. Esse ambiente recebe quantidades significativas de residuos e material orgânico a partir de uma grande variedade de fontes, que inclui as contribuicoes terrigenas, descarga de esgoto, deposicao atmosferica, trafego de embarcacoes e as atividades pesqueiras e portuarias de pequeno porte. Este trabalho determinou as concentracoes de hidrocarbonetos policiclicos aromaticos (HPAs) no material particulado em suspensao (MPS) em dois periodos (inverno de 2014 e verao de 2015), identificando as possiveis fontes antropicas destes compostos. Os HPAs foram obtidos atraves de extracao em Soxhlet, purificados em coluna de adsorcao, identificados e quantificados em um cromatografo gasoso acoplados a um espectrometro de massa (GC/MS) para a identificacao e quantificacao dos hidrocarbonetos. As concentracoes totais de HPAs variaram entre...
Orientador : Prof. Dr. César de Castro MartinsMonografia (graduação) - Universidade Federal do Pa... more Orientador : Prof. Dr. César de Castro MartinsMonografia (graduação) - Universidade Federal do Paraná, Setor de Ciências da Terra, Centro de Estudos do Mar, Curso de OceanografiaResumo: Potter Cove (62 ‹14 fS, 58 ‹39 fO) e um pequeno fiorde na costa sudoeste da Ilha Rei George, Arquipelago Shetlands do Sul, e onde esta situada a estacao de pesquisa argentina Carlini. A fim de avaliar um possivel quadro de contaminacao por oleo e esgoto na regiao, foram coletadas 16 amostras de sedimentos superficiais, onde foram determinadas diferentes classes de marca-dores organicos geoquimicos: hidrocarbonetos alifaticos (HAs), hidrocarbonetos policiclicos aromaticos (HPAs), alquilbenzenos lineares (LABs) e esteroides. As concentracoes de HAs em Potter Cove variaram entre 1,097 e 3,229 ƒÊg.g-1, as de HPAs foram de 12,05 a 210,02 ng.g-1, as de LABs variaram entre 0,26 e 1,67 ng.g-1, enquanto as concentracoes de esteroides variaram entre 3,60 e 10,64 ƒÊg.g-1. As maiores concentracoes foram encontradas no centro da enseada, local de maiores profundidades e menor hidrodinamica, o que favorece o acu-mulo de sedimentos finos e de compostos organicos. Indices envolvendo hidro-carbonetos indicaram a predominancia de compostos leves, oriundos de residuos de oleo ou de producao fitoplanctonica em quase toda a baia. Ja a porcao central apresentou hidrocarbonetos provenientes da combustao de biomassa vegetal e de combustiveis fosseis. Os marcadores de esgoto manti-veram-se abaixo dos limites estabelecidos para areas contaminadas. Sendo assim, a principal fonte de esterois esta associada a presenca de florestas de macroalgas na desembocadura do fiorde e a um pequeno enriquecimento organico proximo a estacao Carlini. As amostras coletadas na Ilha Nelson apresentaram baixas concentracoes, principalmente pela distancia de fontes potenciais. Ja as amostras da Ilha Ardley apresentaram valores na mesma faixa observada em Potter Cove, devido a influencia da estacao chinesa Great Wall. Assim, os resultados deste estudo mostraram que, apesar da deteccao de compostos relacionados a atividades humanas, a regiao de Potter Cove pode ser considerada como nao contaminada por hidrocarbonetos de petroleo e por esgoto, devido as baixas concentracoes encontradas, associadas a hidrodi-namica local, que favorece a dispersao dos poluentes.Abstract: Potter Cove (62°14’S, 58°39’W) is a small fjord on the southwest coast of King George Island, South Shetland Islands, and where the Argentine Carlini station is located. In order to evaluate a possible contamination by oil and/or sewage, 16 sediment sample were collected to analyze different organic compounds: aliphatic hydrocarbons (AHs), polycyclic aromatic hydrocarbons (PAHs), linear alkylbenzenes (LABs) and steroids. The AHs concentrations varied between 1.097 and 3.229 ìg.g-1, the PAHs between 12.05 and 210.02 ng.g-1, the LABs from 0.26 to 1.67 ng.g-1, and the steroids between 3.60 and 10.64 ìg.g-1. The highest values were found in the fjords central portion, the deeper and less dynamic region, where the fine sediments deposition and the subsequent accumulation of organic compounds occur. To assess the organic matter origin, indexes using n-alkanes were calculated and indicated the predominance of low molecular weight compounds, derived from oil residuals or phytoplanktonic production in almost all the bay. Only the central portion of the study site showed evidences of hydrocarbons from vegetal biomass or fossil fuel combustion. The sewage markers remained below the established limit for polluted areas. Therefore, the main source of steroids is associated with the seaweed forest on the fjord inlet and a little organic enrichment near the station beach. The samples taken at Nelson Island presented low concentrations of all compounds, probably due to the distance from potential sources. On the other hand, the Ardley Island values were in the same range observed in Potter Cove, most likely due to the influence of the Chinese Great Wall station. These results showed that, despite of the detection of organic compounds related to human activities, the Potter Cove region can be considered as an unpolluted area by oil hydrocarbons and sewage
Organic Geochemistry, 2021
Abstract Isoprenoidal glycerol dialkyl glycerol tetraethers (isoGDGTs) are archaeal biomarkers. I... more Abstract Isoprenoidal glycerol dialkyl glycerol tetraethers (isoGDGTs) are archaeal biomarkers. In many settings, the degree of cyclization of isoGDGTs is correlated with temperature, forming the basis of the TEX86 paleothermometer that is widely used to reconstruct sea surface temperature (SST) across a range of time scales. However, the application of TEX86 to the polar regions is relatively limited and there is currently no consensus on which calibration is best suited for polar environments. In addition, application of TEX86 to the polar regions is complicated by uncertainty regarding the source of organic matter input in coastal polar environments. We tested five different calibrations for TEX86 in marine sediments from the Antarctic coastal region of Admiralty Bay near King George Island, using four short cores that span the second half of the 20th century. We also explored the possible sources of organic matter in these cores using sterol biomarkers. Best results for TEX86 were obtained using a quadratic calibration. The TEX86 signal presented a strong seasonal signal and best matched reanalysis temperatures of the austral spring season (Oct-Nov-Dec). The most abundant compounds observed in the sediments were the sterols cholest-5-en-3β-ol and 24-ethylcholest-5-en-3β-ol, the fatty alcohols C16 and phytol, and isoGDGT-0, indicating a dominant marine origin of the organic matter. Differences in their vertical distributions suggests that some compounds (such as cholest-5-en-3β-ol and phytol) may have had different sources over the evaluated period. Together our results indicate that TEX86 can be used to reconstruct SSTs in the Antarctic coastal region.
Science of The Total Environment, 2021
Organic biomarkers, as aliphatic hydrocarbons, are present in sedimentary organic matter and have... more Organic biomarkers, as aliphatic hydrocarbons, are present in sedimentary organic matter and have been largely applied to the evaluation of recent environmental changes in the marine environment around the globe, including the Antarctic continent. Five sediment cores were taken in the Admiralty Bay, South Shetland Archipelago, Antarctica to evaluate changes in the signature of aliphatic hydrocarbons such as n-alkanes (n-C10 to n-C40) and isoprenoids as pristane and phytane, over the last decades. The total n-alkanes concentration ranged from 0.17 to 1.67 μg g-1 (mean = 0.74 ± 0.42) which is considered low and similar to pristine sediments. Aliphatic hydrocarbons present in the sedimentary pool came mostly from terrestrial sources as Antarctic lichens and mosses, and from marine sources as the macroalgae forest debris and emergent macrophytes. Anthropogenic inputs of aliphatic hydrocarbons (e.g., petroleum and their by-products) may be neglected based on the multi-proxy approach used to distinct sources of these organic compounds. In general, no significant changes in the sources of aliphatic hydrocarbons were observed along the sediment cores; however, an increased aliphatic hydrocarbons input registered between 1975 and 1992 may be related to the increase in meltwater runoff and the relatively high abundance of marine producers more adapted to increased sea temperatures.
Organic Geochemistry, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Chemosphere, 2020
Tracking the sources of allochthonous organic matter along a subtropical fluvial-estuarine gradie... more Tracking the sources of allochthonous organic matter along a subtropical fluvial-estuarine gradient using molecular proxies in view of land uses, Chemosphere (2020), doi: https://doi.org/10.1016/ j.chemosphere.2020.126435. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Quaternary Science Reviews, 2019
Millennial-scale oscillations are known to be important in the climatic evolution of the Atlantic... more Millennial-scale oscillations are known to be important in the climatic evolution of the Atlantic basin, but which internal processes originates these oscillations are still uncertain. In this study, we investigated how the Greenland and Antarctic climates affect the SW Atlantic through basin-wide oceanographic features (such as the NADW formation and the Agulhas leakage). We reconstructed sea surface and subsurface temperatures (SST and subT) using three lipid-based biomarker proxies (U K' 37 , TEX 86 and LDI indexes) from a sediment core (NAP 63-1) retrieved from the SW Atlantic slope (24.8 S, 44.3 W). This location allowed us to evaluate the temperature oscillations of the Brazil Current without any terrigenous or upwelling-derived biases. Both TEX 86-based and LDI-based estimates represent the mean annual SST, while the U K' 37-based estimates represent the subT (around 30 m water depth). The periods with the most well-mixed water column were observed during intervals of cooling orbital trends due to the time required to transfer the surface cooling to the subsurface. The temperature reconstructions showed a general colder MIS 3 when compared to the MIS 4. They also showed evidence of a late response to deglaciation, with its onset in the SW Atlantic occurring in the middle of the Last Glacial Maximum. Based on these reconstructions, the NAP 63-1 SST orbital-scale trend seems to be linked to the Antarctic climate, influenced by local insolation changes. These temperature records also presented a clear millennial periodicity around 8 kyr. On this timescale, the millennial oscillations in the SW Atlantic's SST are likely linked to the NADW formation.
Journal of environmental management, 2018
The concentration, distribution, and ecological risk of hydrocarbons, as well as bulk parameters,... more The concentration, distribution, and ecological risk of hydrocarbons, as well as bulk parameters, were determined in surface sediments of the Babitonga Bay, a subtropical human-impacted estuary in South Atlantic. Total aliphatic and polycyclic aromatic hydrocarbons (PAHs) ranged between 0.8 and 201.2 μg g and from 8.7 to 5489 ng g, respectively. Saguaçú Lagoon, the region near the ferry boat and the vicinity of São Francisco harbour (SFH), presented high hydrocarbon concentrations. Despite the low accumulation trend in this region, the SFH and city may act as a punctual hydrocarbon source. The inner portion of the estuary had the finest sediment grains and the highest concentrations of carbon, nitrogen, and sulphur, indicating its importance as a depositional and cumulative area. The occurrence of unresolved complex mixture suggested chronic oil contamination. Petrogenic (based on the high percentage of alkylated PAHs) and pyrolytic (according to the diagnostic ratios of PAH isomer ...
Environmental Technology & Innovation, 2016
Abstract Guaratuba Bay is a subtropical estuary located in an Environmental Protection Area and b... more Abstract Guaratuba Bay is a subtropical estuary located in an Environmental Protection Area and between two touristic cities, which are strongly influenced by seasonal increased population during austral summer. To evaluate the recent introduction of polycyclic aromatic hydrocarbons (PAHs) in Guaratuba Bay, samples of surficial suspended particulate matter (SPM) were collected at 22 sites and at three different times. PAHs were determined by gas chromatography coupled to a mass spectrometer (GC/MS). The studied area was sectored according to hydrological parameters. The highest PAH concentrations were observed during the Carnival period due to the tourism and population increase. Spatially, the highest concentrations were verified in the mesohaline and euhaline estuarine regions and were related to the environmental characteristics that facilitate material accumulation and the proximity to ship docks, respectively. The diagnostic ratios and the principal component analysis suggest that the main sources of PAHs are petrogenic inputs related to the boat traffic.
Polar Biology, 2017
degradation degrees. First, relatively fresh phytoplankton organic matter and an enhanced bacteri... more degradation degrees. First, relatively fresh phytoplankton organic matter and an enhanced bacterial activity were associated with the occurrence of seaweeds detritus and represent the source of n-alkanols. Second, relatively fresh material mainly associated with seaweeds debris were identified as the source of macroalgae sterols. Our results shed some light into the base of the Potter Cove trophic benthic chain and increase our understanding on the region's biogeochemical processes relating to OM recycling. It also provides a baseline for assessing future changes in the structure of the benthic food web in this environment, which is subject to noticeable glaciers retreat.
Antarctic Science, 2016
Lipid biomarkers are potential tools for identifying the sources, diagenesis and reactivity of or... more Lipid biomarkers are potential tools for identifying the sources, diagenesis and reactivity of organic matter (OM) in marine systems, including in Antarctica where the particular environmental characteristics have motivated several studies of organic markers. Sedimentary sterol distributions were determined in two sediment cores (PGI-1 and PGI-2) collected from the marine environment around Penguin Island, Antarctica, during the 2007–08 summer. The cores were sectioned at 1 cm intervals and the sterols were analysed using gas chromatography with flame ionization detection. The results indicate that the sterols were subjected to decades of degradation and transformation with depth in both cores. However, an expected progressive conversion of stenols to stanols (evaluated by 5α-stanols/Δ5-stenols ratio) within the deepest sediment layers was not clear, suggesting low degradation rates. In PGI-1, the deposition of large quantities of penguin guano affected the distribution of sterols a...
Environmental pollution (Barking, Essex : 1987), Jan 15, 2016
The Paranaguá Estuarine Complex (PEC) is an important socioeconomic estuary of the Brazilian coas... more The Paranaguá Estuarine Complex (PEC) is an important socioeconomic estuary of the Brazilian coast that is influenced by the input of pollutants like polycyclic aromatic hydrocarbons (PAHs). Because of the apparent lack of comparative studies involving PAHs in different estuarine compartments, the aim of this study was to determine and compare PAH concentrations in surface sediment and suspended particulate material (SPM) in the PEC to evaluate their behaviour, compositions, sources and spatial distributions. The total PAH concentrations in the sediment ranged from 0.6 to 63.8 ng g(-1) (dry weight), whereas in the SPM these concentrations ranged from 391 to 4164 ng g(-1). Diagnostic ratios suggest distinct sources of PAHs to sediments (i.e., pyrolytic sources) and SPM (i.e., petrogenic sources such as vessel traffic). Thus, the recent introduction of PAHs is more clearly indicated in the SPM since oil related-compounds (e.g., alkyl-PAHs) remain present in similar concentrations. Fur...
Science of The Total Environment, 2015
Guaratuba Bay, a subtropical estuary located in the SW Atlantic, is under variable anthropogenic ... more Guaratuba Bay, a subtropical estuary located in the SW Atlantic, is under variable anthropogenic pressure throughout the year. Samples of surficial suspended particulate matter (SPM) were collected at 22 sites during three different periods to evaluate the temporal and spatial variability of aliphatic hydrocarbons (AHs) and linear alkylbenzenes (LABs). These compounds were determined by gas chromatography with flame ionization detection (GC-FID) and mass spectrometry (GC/MS). The spatial distributions of both compound classes were similar and varied among the sampling campaigns. Generally, the highest concentrations were observed during the austral summer, highlighting the importance of the increased human influence during this season. The compound distributions were also affected by the natural geochemical processes of organic matter accumulation. AHs were associated with petroleum, derived from boat and vehicle traffic, and biogenic sources, related to mangrove forests and autochthonous production. The LAB composition evidenced preferential degradation processes during the austral summer.
Brazilian Journal of Oceanography, 2015
Situated opposite the Freshwater Front, Montevideo city with its more than 1.5 million inhabitant... more Situated opposite the Freshwater Front, Montevideo city with its more than 1.5 million inhabitants encircles Montevideo Bay, where one of the most active and polluted harbors in South America is located. Faecal sterols, trace metals, organochlorine compounds and petroleum derivatives in the sediments of Montevideo Harbor were evaluated and their spatial distribution inside the harbor as well as in the input of two main tributary streams analyzed. Specifically for the harbor sites, a temporal comparison of metal and hydrocarbons was made with previous measurements taken 12 years ago. Clear changes were observed at these sites. The concentration of metals such as Pb, Cr and Zn have diminished, while aliphatic hydrocarbons have increased their values at almost all of the stations studied. Differences were observed between summer and winter suggesting sedimentation, input or hydrodynamic changes in the area. These results help one to understand the present situation and develop the mana...
Environmental Pollution, 2015
Spectroscopic and chromatographic techniques can be used together to evaluate hydrocarbon inputs ... more Spectroscopic and chromatographic techniques can be used together to evaluate hydrocarbon inputs to coastal environments such as the Paranagu a estuarine system (PES), located in the SW Atlantic, Brazil. Historical inputs of aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs) were analyzed using two sediment cores from the PES. The AHs were related to the presence of biogenic organic matter and degraded oil residues. The PAHs were associated with mixed sources. The highest hydrocarbon concentrations were related to oil spills, while relatively low levels could be attributed to the decrease in oil usage during the global oil crisis. The results of electron paramagnetic resonance were in agreement with the absolute AHs and PAHs concentrations measured by chromatographic techniques, while near-infrared spectroscopy results were consistent with unresolved complex mixture (UCM)/total n-alkanes ratios. These findings suggest that the use of a combination of techniques can increase the accuracy of assessment of contamination in sediments.
INCT-APA Annual Activity Report, 2015
Potter Cove (62°14'S, 58°39'W) is a small fjord on the southwest coast of King George Island, Sou... more Potter Cove (62°14'S, 58°39'W) is a small fjord on the southwest coast of King George Island, South Shetland Islands, and where the Argentine Carlini station is located. In order to evaluate a possible input of oil and/or sewage, related to anthropogenic activities, 12 sediment samples were collected to analyze different organic markers: aliphatic and aromatic hydrocarbons, and fecal sterols. The concentrations of aliphatic and polycyclic aromatic hydrocarbons were lower in comparison to marine sediments contaminated by oil hydrocarbons, indicating natural sources and little contribution from petrogenic and combustion sources of these compounds. The concentrations of sewage molecular markers were lower than levels found in contaminated areas and other Antarctic places. Despite the detection of organic compounds related to human activities, these results showed that the Potter Cove region may be considered less impacted by oil hydrocarbons and sewage input.
Science of The Total Environment, 2015
• Concentrations of oil and sewage markers were determined in Antarctic sediments. • Despite the ... more • Concentrations of oil and sewage markers were determined in Antarctic sediments. • Despite the anthropogenic sources of AHs, biogenic input was predominant. • PAHs were found to be associated with petrogenic sources. • Low concentrations of coprostanol provide no evidences of sewage pollution.
Orientador : Dr. César de Castro MartinsDissertação (mestrado) - Universidade Federal do Paraná, ... more Orientador : Dr. César de Castro MartinsDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Terra, Programa de Pós-Graduação em Sistemas Costeiros e Oceânicos. Defesa: Pontal do Paraná, 24/04/2015Inclui referênciasResumo: O objetivo desta dissertação foi avaliar a distribuição espacial e temporal, de curta escala, de hidrocarbonetos (hidrocarbonetos policíclicos aromáticos - HPAs, hidrocarbonetos alifáticos - HAs, Alquilbenzenos lineares - LABs) no material particulado em suspensão (MPS) da Baía de Guaratuba, PR, Brasil, bem como identificar as suas principais fontes e verificar como os parâmetros da coluna d'água afetam a sua distribuição. Para tanto, foram coletadas 22 amostras em três períodos distintos (04/2013, 08/2013 e 03/2014). De um modo geral, foram observados altos valores na porção mediana do estuário, relacionados a fenômenos hidrodinâmicos que contribuem para o acúmulo de matéria orgânica, gerando uma região atuante como um filtro geoquími...
Millennial-scale oscillations are known to be important in the climatic evolution of the Atlantic... more Millennial-scale oscillations are known to be important in the climatic evolution of the Atlantic basin, but which internal processes originates these oscillations are still uncertain. In this study, we investigated how the Greenland and Antarctic climates affect the SW Atlantic through basin-wide oceanographic features (such as the NADW formation and the Agulhas leakage). We reconstructed sea surface and subsurface temperatures (SST and subT) using three lipid-based biomarker proxies (UK'37, TEX86 and LDI indexes) from a sediment core (NAP 63-1) retrieved from the SW Atlantic slope (24.8°S, 44.3°W). This location permitted to evaluate the temperature oscillations of the Brazil Current without any terrigenous or upwelling-derived biases. Both TEX86-based and LDI-based estimates represent the mean annual SST, while the UK'37-based estimates represent the subT (around 30 m water depth). The periods with the most well-mixed water column were observed during intervals of cooling...
Hydrocarbons are organic geochemical markers found in biogenic organic matter, crude oil and thei... more Hydrocarbons are organic geochemical markers found in biogenic organic matter, crude oil and their by-products, and also in residues of burned fossil fuels and biomass. High levels of anthropogenic hydrocarbons, as polycyclic aromatic hydrocarbons (PAHs) may cause ecosystem and human health damage due the toxic and mutagenic effects. Guaratuba Bay is located on SW Atlantic coast, Brazil (25°52'S; 48°38'O). This region is within an Environmental Protected Area where Atlantic Forest remains relatively pristine. Guaratuba Bay also presents increased human occupation and tourism in summer period, what may contribute to anthropic impacts related to the hydrocarbon input. The main objective of this study was to evaluate the spatial distribution of aliphatic (AHs) and PAHs in a total of eleven surface sediments of Guaratuba Bay, collected in October 2010. Samples were freeze-dried, carefully homogenized with a mortar, extracted and purified. Subsequently, hydrocarbon concentrations...
A urbanizacao, agricultura, pecuaria, pesca e o turismo sao as principais atividades antropicas e... more A urbanizacao, agricultura, pecuaria, pesca e o turismo sao as principais atividades antropicas exercidas na Baia de Guaratuba, localizada na regiao Sul do Brasil. Esse ambiente recebe quantidades significativas de residuos e material orgânico a partir de uma grande variedade de fontes, que inclui as contribuicoes terrigenas, descarga de esgoto, deposicao atmosferica, trafego de embarcacoes e as atividades pesqueiras e portuarias de pequeno porte. Este trabalho determinou as concentracoes de hidrocarbonetos policiclicos aromaticos (HPAs) no material particulado em suspensao (MPS) em dois periodos (inverno de 2014 e verao de 2015), identificando as possiveis fontes antropicas destes compostos. Os HPAs foram obtidos atraves de extracao em Soxhlet, purificados em coluna de adsorcao, identificados e quantificados em um cromatografo gasoso acoplados a um espectrometro de massa (GC/MS) para a identificacao e quantificacao dos hidrocarbonetos. As concentracoes totais de HPAs variaram entre...
Orientador : Prof. Dr. César de Castro MartinsMonografia (graduação) - Universidade Federal do Pa... more Orientador : Prof. Dr. César de Castro MartinsMonografia (graduação) - Universidade Federal do Paraná, Setor de Ciências da Terra, Centro de Estudos do Mar, Curso de OceanografiaResumo: Potter Cove (62 ‹14 fS, 58 ‹39 fO) e um pequeno fiorde na costa sudoeste da Ilha Rei George, Arquipelago Shetlands do Sul, e onde esta situada a estacao de pesquisa argentina Carlini. A fim de avaliar um possivel quadro de contaminacao por oleo e esgoto na regiao, foram coletadas 16 amostras de sedimentos superficiais, onde foram determinadas diferentes classes de marca-dores organicos geoquimicos: hidrocarbonetos alifaticos (HAs), hidrocarbonetos policiclicos aromaticos (HPAs), alquilbenzenos lineares (LABs) e esteroides. As concentracoes de HAs em Potter Cove variaram entre 1,097 e 3,229 ƒÊg.g-1, as de HPAs foram de 12,05 a 210,02 ng.g-1, as de LABs variaram entre 0,26 e 1,67 ng.g-1, enquanto as concentracoes de esteroides variaram entre 3,60 e 10,64 ƒÊg.g-1. As maiores concentracoes foram encontradas no centro da enseada, local de maiores profundidades e menor hidrodinamica, o que favorece o acu-mulo de sedimentos finos e de compostos organicos. Indices envolvendo hidro-carbonetos indicaram a predominancia de compostos leves, oriundos de residuos de oleo ou de producao fitoplanctonica em quase toda a baia. Ja a porcao central apresentou hidrocarbonetos provenientes da combustao de biomassa vegetal e de combustiveis fosseis. Os marcadores de esgoto manti-veram-se abaixo dos limites estabelecidos para areas contaminadas. Sendo assim, a principal fonte de esterois esta associada a presenca de florestas de macroalgas na desembocadura do fiorde e a um pequeno enriquecimento organico proximo a estacao Carlini. As amostras coletadas na Ilha Nelson apresentaram baixas concentracoes, principalmente pela distancia de fontes potenciais. Ja as amostras da Ilha Ardley apresentaram valores na mesma faixa observada em Potter Cove, devido a influencia da estacao chinesa Great Wall. Assim, os resultados deste estudo mostraram que, apesar da deteccao de compostos relacionados a atividades humanas, a regiao de Potter Cove pode ser considerada como nao contaminada por hidrocarbonetos de petroleo e por esgoto, devido as baixas concentracoes encontradas, associadas a hidrodi-namica local, que favorece a dispersao dos poluentes.Abstract: Potter Cove (62°14’S, 58°39’W) is a small fjord on the southwest coast of King George Island, South Shetland Islands, and where the Argentine Carlini station is located. In order to evaluate a possible contamination by oil and/or sewage, 16 sediment sample were collected to analyze different organic compounds: aliphatic hydrocarbons (AHs), polycyclic aromatic hydrocarbons (PAHs), linear alkylbenzenes (LABs) and steroids. The AHs concentrations varied between 1.097 and 3.229 ìg.g-1, the PAHs between 12.05 and 210.02 ng.g-1, the LABs from 0.26 to 1.67 ng.g-1, and the steroids between 3.60 and 10.64 ìg.g-1. The highest values were found in the fjords central portion, the deeper and less dynamic region, where the fine sediments deposition and the subsequent accumulation of organic compounds occur. To assess the organic matter origin, indexes using n-alkanes were calculated and indicated the predominance of low molecular weight compounds, derived from oil residuals or phytoplanktonic production in almost all the bay. Only the central portion of the study site showed evidences of hydrocarbons from vegetal biomass or fossil fuel combustion. The sewage markers remained below the established limit for polluted areas. Therefore, the main source of steroids is associated with the seaweed forest on the fjord inlet and a little organic enrichment near the station beach. The samples taken at Nelson Island presented low concentrations of all compounds, probably due to the distance from potential sources. On the other hand, the Ardley Island values were in the same range observed in Potter Cove, most likely due to the influence of the Chinese Great Wall station. These results showed that, despite of the detection of organic compounds related to human activities, the Potter Cove region can be considered as an unpolluted area by oil hydrocarbons and sewage
Organic Geochemistry, 2021
Abstract Isoprenoidal glycerol dialkyl glycerol tetraethers (isoGDGTs) are archaeal biomarkers. I... more Abstract Isoprenoidal glycerol dialkyl glycerol tetraethers (isoGDGTs) are archaeal biomarkers. In many settings, the degree of cyclization of isoGDGTs is correlated with temperature, forming the basis of the TEX86 paleothermometer that is widely used to reconstruct sea surface temperature (SST) across a range of time scales. However, the application of TEX86 to the polar regions is relatively limited and there is currently no consensus on which calibration is best suited for polar environments. In addition, application of TEX86 to the polar regions is complicated by uncertainty regarding the source of organic matter input in coastal polar environments. We tested five different calibrations for TEX86 in marine sediments from the Antarctic coastal region of Admiralty Bay near King George Island, using four short cores that span the second half of the 20th century. We also explored the possible sources of organic matter in these cores using sterol biomarkers. Best results for TEX86 were obtained using a quadratic calibration. The TEX86 signal presented a strong seasonal signal and best matched reanalysis temperatures of the austral spring season (Oct-Nov-Dec). The most abundant compounds observed in the sediments were the sterols cholest-5-en-3β-ol and 24-ethylcholest-5-en-3β-ol, the fatty alcohols C16 and phytol, and isoGDGT-0, indicating a dominant marine origin of the organic matter. Differences in their vertical distributions suggests that some compounds (such as cholest-5-en-3β-ol and phytol) may have had different sources over the evaluated period. Together our results indicate that TEX86 can be used to reconstruct SSTs in the Antarctic coastal region.
Science of The Total Environment, 2021
Organic biomarkers, as aliphatic hydrocarbons, are present in sedimentary organic matter and have... more Organic biomarkers, as aliphatic hydrocarbons, are present in sedimentary organic matter and have been largely applied to the evaluation of recent environmental changes in the marine environment around the globe, including the Antarctic continent. Five sediment cores were taken in the Admiralty Bay, South Shetland Archipelago, Antarctica to evaluate changes in the signature of aliphatic hydrocarbons such as n-alkanes (n-C10 to n-C40) and isoprenoids as pristane and phytane, over the last decades. The total n-alkanes concentration ranged from 0.17 to 1.67 μg g-1 (mean = 0.74 ± 0.42) which is considered low and similar to pristine sediments. Aliphatic hydrocarbons present in the sedimentary pool came mostly from terrestrial sources as Antarctic lichens and mosses, and from marine sources as the macroalgae forest debris and emergent macrophytes. Anthropogenic inputs of aliphatic hydrocarbons (e.g., petroleum and their by-products) may be neglected based on the multi-proxy approach used to distinct sources of these organic compounds. In general, no significant changes in the sources of aliphatic hydrocarbons were observed along the sediment cores; however, an increased aliphatic hydrocarbons input registered between 1975 and 1992 may be related to the increase in meltwater runoff and the relatively high abundance of marine producers more adapted to increased sea temperatures.
Organic Geochemistry, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Chemosphere, 2020
Tracking the sources of allochthonous organic matter along a subtropical fluvial-estuarine gradie... more Tracking the sources of allochthonous organic matter along a subtropical fluvial-estuarine gradient using molecular proxies in view of land uses, Chemosphere (2020), doi: https://doi.org/10.1016/ j.chemosphere.2020.126435. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Quaternary Science Reviews, 2019
Millennial-scale oscillations are known to be important in the climatic evolution of the Atlantic... more Millennial-scale oscillations are known to be important in the climatic evolution of the Atlantic basin, but which internal processes originates these oscillations are still uncertain. In this study, we investigated how the Greenland and Antarctic climates affect the SW Atlantic through basin-wide oceanographic features (such as the NADW formation and the Agulhas leakage). We reconstructed sea surface and subsurface temperatures (SST and subT) using three lipid-based biomarker proxies (U K' 37 , TEX 86 and LDI indexes) from a sediment core (NAP 63-1) retrieved from the SW Atlantic slope (24.8 S, 44.3 W). This location allowed us to evaluate the temperature oscillations of the Brazil Current without any terrigenous or upwelling-derived biases. Both TEX 86-based and LDI-based estimates represent the mean annual SST, while the U K' 37-based estimates represent the subT (around 30 m water depth). The periods with the most well-mixed water column were observed during intervals of cooling orbital trends due to the time required to transfer the surface cooling to the subsurface. The temperature reconstructions showed a general colder MIS 3 when compared to the MIS 4. They also showed evidence of a late response to deglaciation, with its onset in the SW Atlantic occurring in the middle of the Last Glacial Maximum. Based on these reconstructions, the NAP 63-1 SST orbital-scale trend seems to be linked to the Antarctic climate, influenced by local insolation changes. These temperature records also presented a clear millennial periodicity around 8 kyr. On this timescale, the millennial oscillations in the SW Atlantic's SST are likely linked to the NADW formation.
Journal of environmental management, 2018
The concentration, distribution, and ecological risk of hydrocarbons, as well as bulk parameters,... more The concentration, distribution, and ecological risk of hydrocarbons, as well as bulk parameters, were determined in surface sediments of the Babitonga Bay, a subtropical human-impacted estuary in South Atlantic. Total aliphatic and polycyclic aromatic hydrocarbons (PAHs) ranged between 0.8 and 201.2 μg g and from 8.7 to 5489 ng g, respectively. Saguaçú Lagoon, the region near the ferry boat and the vicinity of São Francisco harbour (SFH), presented high hydrocarbon concentrations. Despite the low accumulation trend in this region, the SFH and city may act as a punctual hydrocarbon source. The inner portion of the estuary had the finest sediment grains and the highest concentrations of carbon, nitrogen, and sulphur, indicating its importance as a depositional and cumulative area. The occurrence of unresolved complex mixture suggested chronic oil contamination. Petrogenic (based on the high percentage of alkylated PAHs) and pyrolytic (according to the diagnostic ratios of PAH isomer ...
Environmental Technology & Innovation, 2016
Abstract Guaratuba Bay is a subtropical estuary located in an Environmental Protection Area and b... more Abstract Guaratuba Bay is a subtropical estuary located in an Environmental Protection Area and between two touristic cities, which are strongly influenced by seasonal increased population during austral summer. To evaluate the recent introduction of polycyclic aromatic hydrocarbons (PAHs) in Guaratuba Bay, samples of surficial suspended particulate matter (SPM) were collected at 22 sites and at three different times. PAHs were determined by gas chromatography coupled to a mass spectrometer (GC/MS). The studied area was sectored according to hydrological parameters. The highest PAH concentrations were observed during the Carnival period due to the tourism and population increase. Spatially, the highest concentrations were verified in the mesohaline and euhaline estuarine regions and were related to the environmental characteristics that facilitate material accumulation and the proximity to ship docks, respectively. The diagnostic ratios and the principal component analysis suggest that the main sources of PAHs are petrogenic inputs related to the boat traffic.
Polar Biology, 2017
degradation degrees. First, relatively fresh phytoplankton organic matter and an enhanced bacteri... more degradation degrees. First, relatively fresh phytoplankton organic matter and an enhanced bacterial activity were associated with the occurrence of seaweeds detritus and represent the source of n-alkanols. Second, relatively fresh material mainly associated with seaweeds debris were identified as the source of macroalgae sterols. Our results shed some light into the base of the Potter Cove trophic benthic chain and increase our understanding on the region's biogeochemical processes relating to OM recycling. It also provides a baseline for assessing future changes in the structure of the benthic food web in this environment, which is subject to noticeable glaciers retreat.
Antarctic Science, 2016
Lipid biomarkers are potential tools for identifying the sources, diagenesis and reactivity of or... more Lipid biomarkers are potential tools for identifying the sources, diagenesis and reactivity of organic matter (OM) in marine systems, including in Antarctica where the particular environmental characteristics have motivated several studies of organic markers. Sedimentary sterol distributions were determined in two sediment cores (PGI-1 and PGI-2) collected from the marine environment around Penguin Island, Antarctica, during the 2007–08 summer. The cores were sectioned at 1 cm intervals and the sterols were analysed using gas chromatography with flame ionization detection. The results indicate that the sterols were subjected to decades of degradation and transformation with depth in both cores. However, an expected progressive conversion of stenols to stanols (evaluated by 5α-stanols/Δ5-stenols ratio) within the deepest sediment layers was not clear, suggesting low degradation rates. In PGI-1, the deposition of large quantities of penguin guano affected the distribution of sterols a...
Environmental pollution (Barking, Essex : 1987), Jan 15, 2016
The Paranaguá Estuarine Complex (PEC) is an important socioeconomic estuary of the Brazilian coas... more The Paranaguá Estuarine Complex (PEC) is an important socioeconomic estuary of the Brazilian coast that is influenced by the input of pollutants like polycyclic aromatic hydrocarbons (PAHs). Because of the apparent lack of comparative studies involving PAHs in different estuarine compartments, the aim of this study was to determine and compare PAH concentrations in surface sediment and suspended particulate material (SPM) in the PEC to evaluate their behaviour, compositions, sources and spatial distributions. The total PAH concentrations in the sediment ranged from 0.6 to 63.8 ng g(-1) (dry weight), whereas in the SPM these concentrations ranged from 391 to 4164 ng g(-1). Diagnostic ratios suggest distinct sources of PAHs to sediments (i.e., pyrolytic sources) and SPM (i.e., petrogenic sources such as vessel traffic). Thus, the recent introduction of PAHs is more clearly indicated in the SPM since oil related-compounds (e.g., alkyl-PAHs) remain present in similar concentrations. Fur...
Science of The Total Environment, 2015
Guaratuba Bay, a subtropical estuary located in the SW Atlantic, is under variable anthropogenic ... more Guaratuba Bay, a subtropical estuary located in the SW Atlantic, is under variable anthropogenic pressure throughout the year. Samples of surficial suspended particulate matter (SPM) were collected at 22 sites during three different periods to evaluate the temporal and spatial variability of aliphatic hydrocarbons (AHs) and linear alkylbenzenes (LABs). These compounds were determined by gas chromatography with flame ionization detection (GC-FID) and mass spectrometry (GC/MS). The spatial distributions of both compound classes were similar and varied among the sampling campaigns. Generally, the highest concentrations were observed during the austral summer, highlighting the importance of the increased human influence during this season. The compound distributions were also affected by the natural geochemical processes of organic matter accumulation. AHs were associated with petroleum, derived from boat and vehicle traffic, and biogenic sources, related to mangrove forests and autochthonous production. The LAB composition evidenced preferential degradation processes during the austral summer.
Brazilian Journal of Oceanography, 2015
Situated opposite the Freshwater Front, Montevideo city with its more than 1.5 million inhabitant... more Situated opposite the Freshwater Front, Montevideo city with its more than 1.5 million inhabitants encircles Montevideo Bay, where one of the most active and polluted harbors in South America is located. Faecal sterols, trace metals, organochlorine compounds and petroleum derivatives in the sediments of Montevideo Harbor were evaluated and their spatial distribution inside the harbor as well as in the input of two main tributary streams analyzed. Specifically for the harbor sites, a temporal comparison of metal and hydrocarbons was made with previous measurements taken 12 years ago. Clear changes were observed at these sites. The concentration of metals such as Pb, Cr and Zn have diminished, while aliphatic hydrocarbons have increased their values at almost all of the stations studied. Differences were observed between summer and winter suggesting sedimentation, input or hydrodynamic changes in the area. These results help one to understand the present situation and develop the mana...
Environmental Pollution, 2015
Spectroscopic and chromatographic techniques can be used together to evaluate hydrocarbon inputs ... more Spectroscopic and chromatographic techniques can be used together to evaluate hydrocarbon inputs to coastal environments such as the Paranagu a estuarine system (PES), located in the SW Atlantic, Brazil. Historical inputs of aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs) were analyzed using two sediment cores from the PES. The AHs were related to the presence of biogenic organic matter and degraded oil residues. The PAHs were associated with mixed sources. The highest hydrocarbon concentrations were related to oil spills, while relatively low levels could be attributed to the decrease in oil usage during the global oil crisis. The results of electron paramagnetic resonance were in agreement with the absolute AHs and PAHs concentrations measured by chromatographic techniques, while near-infrared spectroscopy results were consistent with unresolved complex mixture (UCM)/total n-alkanes ratios. These findings suggest that the use of a combination of techniques can increase the accuracy of assessment of contamination in sediments.
INCT-APA Annual Activity Report, 2015
Potter Cove (62°14'S, 58°39'W) is a small fjord on the southwest coast of King George Island, Sou... more Potter Cove (62°14'S, 58°39'W) is a small fjord on the southwest coast of King George Island, South Shetland Islands, and where the Argentine Carlini station is located. In order to evaluate a possible input of oil and/or sewage, related to anthropogenic activities, 12 sediment samples were collected to analyze different organic markers: aliphatic and aromatic hydrocarbons, and fecal sterols. The concentrations of aliphatic and polycyclic aromatic hydrocarbons were lower in comparison to marine sediments contaminated by oil hydrocarbons, indicating natural sources and little contribution from petrogenic and combustion sources of these compounds. The concentrations of sewage molecular markers were lower than levels found in contaminated areas and other Antarctic places. Despite the detection of organic compounds related to human activities, these results showed that the Potter Cove region may be considered less impacted by oil hydrocarbons and sewage input.
Science of The Total Environment, 2015
• Concentrations of oil and sewage markers were determined in Antarctic sediments. • Despite the ... more • Concentrations of oil and sewage markers were determined in Antarctic sediments. • Despite the anthropogenic sources of AHs, biogenic input was predominant. • PAHs were found to be associated with petrogenic sources. • Low concentrations of coprostanol provide no evidences of sewage pollution.