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Effect of winter storm on water quality and fish toxicity the Duwamish and Nisqually Rivers /Ubilava, Mariam. January 2007 (has links) (PDF)
Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen viewed (1/17/2008). Includes bibliographical references (leaves 67-68).
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Mineralogia de solos e ambientes de sedimentação em manguezais do Estado de São Paulo / Soil mineralogy and sedimentary environment in mangroves of São Paulo StateValdomiro Severino de Souza Júnior 22 February 2006 (has links)
Manguezais são formados por grupos de árvores e arbustos que se desenvolvem na zona de intermarés de regiões tropicais. Este ecossistema ao se estabelecer na interface do ambiente marinho e continental, apresenta sua formação relacionada com as flutuações relativas do nível do mar quaternário, através do preenchimento dos vales dos rios, margens de lagunas e baías com sedimentos tanto de origem continental como marinha. O conhecimento da distribuição de partículas e dos minerais constituintes da assembléia mineralógica dos solos em ambiente de planícies estuarinas, auxilia na compreensão de processos de sedimentação e geoquímica dentro dos estuários. O trabalho foi realizado nos manguezais distribuídos ao longo do litoral do Estado de São Paulo, e objetivou-se caracterizar os ambientes de sedimentação de acordo com a granulometria e o processo de evolução quaternária, determinar qualitativamente e semiquantitativamente a assembléia mineralógica e estudar em detalhe os tipos de esmectitas presentes nesses solos. Para tanto foram coletadas amostras de solos de 14 manguezais nas camadas de 0-20 e 60-80cm e de sedimento em suspensão do Rio Ribeira de Iguape, além de amostras de diferentes profundidades para datações. Determinaram-se as frações, argila, silte, areia total e 5 frações da areia, foram realizadas datações 14C por cintilação líquida e AMS na fração humina da matéria orgânica e por termoluminescência em grãos de quartzo. As análises mineralógicas foram realizadas na fração silte e argila e no sedimento em suspensão através de DRX, IV, MET, MEV com microanálise, ATD e ATG, realizou-se também o teste de Greene- Kelly para identificar o tipo de esmectitas presentes nesses solos. De acordo com os resultados obtidos, concluiu-se que os solos dos manguezais do Estado de São Paulo podem apresentar diferentes texturas desde arenosa até muito argilosa, freqüentemente contêm altos teores de silte e todos têm idade holocênica, oscilando entre 410 anos A.P. e 3.700 anos; a distribuição de partículas está relacionada à morfologia atual do estuário e à natureza dos sedimentos costeiros adjacentes; a assembléia mineralógica da fração fina dos solos é constituída de pirita, nontronita, caulinita, illita, gibbsita, quartzo, feldspato, e localmente ocorrem goethita, vermiculita, biotita, halloysita e anatásio; os minerais alóctones são de origem continental e marinha; a distinção entre os cenários geomorfológicos ao longo do litoral condiciona a distribuição de minerais, e ainda foi inferido que ocorre neoformação de esmectita e de caulinita, e que o processo de oxidação de matéria orgânica nesses solos pode estar utilizando o Fe3+ da nontronita como receptor de elétrons. / Mangroves are formed by groups of trees and shrubs that develop in the intertidal zone of tropical regions. This ecosystem to establish in the interface of both marine and continental environment, present its formation related to the sea-level fluctuations during the quaternary period, where the terrigenous and marine sediments are deposited in rivers valleys, edges of lagoons and bays. The knowledge of both particle distribution and minerals constituent of soils in estuarines areas, can aid to understand the processes of sedimentation and geochemistry in this site. This study was carried out with mangroves distributed along the São Paulo State coast, and aims to characterize the sedimentary environments in accordance with grain size and process of quaternary evolution, to determine qualitatively and semiquantitatively the mineralogical assemblage and to identify the smectites types in these soils. Samples were collected from 14 mangroves soils at the layers 0-20 and 60-80cm, and also was collected sediment in suspension of the Ribeira de Iguape River, and samples of different depths for dating. The clay, silt and total sand sizes and 5 sand fractions were determined, radiocarbon dating were carried out by liquid scintillation counting and accelerator mass spectrometry in humin fraction of the soil organic matter and by thermoluminescence of quartz grains. The mineralogical analyses were carried out by XRD, FTIR, TEM, SEM, DTA and GTA in silt and clay sizes and in the sediment in suspension, also was made the Greene-Kelly test to identify the smectites type. According to the results we concluded that the mangroves soils from São Paulo State have different textures varying from sandy up to very clay, also occuring high silt contents. All the mangroves are holocenic, with ages varying from 410 yr B.P. to 3,700 yr; the particle distribution is related to the current geomorphological setting of the estuary and the origin of coastal sediments. The mineralogical assemblage is constituted of pyrite, nontronite, kaolinite, illite, biotite, gibbsite, quartz, feldspars, and locally occurs goethite, vermiculite, halloysite and anatase; the aloctones minerals are from both the terrigenous and marine origin; the difference between geomorphological settings along the coastal plain rules mineral distribution, and still it was inferred the neoformation of esmectita and kaolinite and that the process of organic matter mineralization in these soils may be using Fe3+ from nontronite as an electron acceptor.
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Caracteriza??o batim?trica e fisicooceanogr?fica do canal de acesso ao porto de Cabedelo/PB: uma an?lise ambiental ao derrame de ?leoFraz?o, Luciana de Sousa 30 June 2011 (has links)
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Previous issue date: 2011-06-30 / The State of Para?ba is one of the most dynamic states of Brazil, strategically located
in the northeast, is notable for the excellent potential for integration of different transportation
modes forming the states of Rio Grande do Norte, Pernambuco and Alagoas. The dynamic
that occurs with port activity causes changes in the space where it is installed. And the
elements of this space are always more than suffering direct or indirect influences as the flow
in the port is expanded. Therefore, this region became subject to the accidental spillage of oil,
because it presents a heavy traffic of ships of various sizes that can run aground or collide
with oil causing accidental events. The study of geomorphological and sedimentological
compositions of seafloor becomes important as more is known about the relationships
between these parameters and associated fauna, and can identify their preferred habitats. The
database background, acoustically collected along the proposed study area, is a wealth of
information, which were duly examined, cataloged and made available. Such information can
serve as an important tool, providing a geomorphological survey of the sedimentary area
studied, and come to subsidize, in a flexible, future decision making. With the study area Port
of Cabedelo, Para?ba - Brazil, this research aimed to evaluate the influence of the tidal surface
and background in modeling the seabed, including the acquisition of information about the
location of submerged rocky bodies and the depth of these bodies may turn out to be natural
traps for the trapping of oil in case of leaks, and obtain the relationship between types of bed
and the hydrodynamic conditions present in the region. In this context, for this study were
collected bathymetric data (depth) and physical oceanographic (height of water column, water
temperature, intensity and direction of currents, waves and turbidity), meteorological (rainfall,
air temperature, humidity, winds and barometric pressure) of the access channel to the Port of
Cabedelo / PB and its basin evolution (where the cruise ships dock), and includes tools of
remote sensing (Landsat 7 ETM +, 2001), so that images and the results are integrated into
Geographic Information Systems and used in the elaboration of measures aimed at
environmental protection areas under the influence of this scale facilities, serving as a grant to
prepare a contingency plan in case of oil spills in the region. The main findings highlight the
techniques of using hydroacoustic data acquisition together bathymetric surveys of high and
low frequency. From there, five were prepared in bathymetric pattern of Directorate of
Hydrography and Navigation - DHN, with the depth in meters, on a scale of 1:2500 (Channel
and Basin Evolution of Access to Port of Cabedelo), where there is a large extent possible
beachrocks that hinder the movement of vessels in the port area, which can cause collisions,
running aground and leaking oil. From the scatter diagram of the vectors of currents, it can be
seen as the tidal stream and undergoes a channeling effect caused by the bidirectional effect of
the tide (ebb and flood) in the basin of the Port of Cabedelo evolution in NW-direction SE and
the highest speed of the currents occurs at low tide. The characterization weather for the
period from 28/02 to 04/07/2010 values was within the expected average for the region of
study. The multidisciplinary integration of products (digital maps and remote sensing images),
proved to be efficient for the characterization of underwater geomorphological study area,
reaching the aim to discriminate and enhance submerged structures, previously not visible in
the images / O Estado da Para?ba ? um dos estados mais din?micos do Brasil, estrategicamente localizado
na regi?o nordeste, se destaca pelo excelente potencial para integra??o dos diversos modais de
transporte formado com os Estados do Rio Grande do Norte, Pernambuco e Alagoas e por
abrigar o Porto de Cabedelo. A din?mica que ocorre com a atividade portu?ria provoca
mudan?as no espa?o onde ele ? instalado. E os elementos que comp?em esse espa?o passam
ent?o a sofrer sempre mais influ?ncias diretas ou indiretas ? medida que o fluxo no porto ?
ampliado. Logo, essa regi?o tornou-se pass?vel ao derramamento acidental de ?leo, por
apresentar um intenso tr?fego de navios de diversos portes que podem encalhar ou colidir
ocasionando eventos acidentais com ?leo. O estudo das composi??es geomorfol?gicas e
sedimentol?gicas do fundo oce?nico tornam-se importantes ? medida que se conhece mais a
respeito de rela??es entre estes par?metros e a fauna associada, sendo poss?vel identificar seus
habitats preferenciais. O banco de dados de fundo, acusticamente coletados ao longo da ?rea
do estudo proposto, constitui um grande acervo de informa??es, que foram devidamente
analisadas, catalogadas e disponibilizadas. Tais informa??es podem servir como uma
importante ferramenta, proporcionando um levantamento geomorfol?gico da ?rea estudada, e
vir a subsidiar, de forma ?gil, futuras tomadas de decis?o. Tendo como ?rea de estudo Porto
de Cabedelo, Para?ba - Brasil, esta pesquisa objetivou avaliar a influ?ncia das correntes de
mar?s superficiais e de fundo na modelagem do leito marinho, incluindo a aquisi??o de
informa??es sobre a localiza??o de corpos rochosos submersos e a profundidade desses
corpos que podem vir a se tornar armadilhas naturais para o aprisionamento de ?leo em casos
de vazamentos, al?m de obter a rela??o entre tipos de leito e as condi??es hidrodin?micas
atuais na regi?o. Nesse contexto, para este trabalho, foram coletados dados batim?tricos
(profundidade) e f?sico-oceanogr?ficos (altura de coluna d ?gua, temperatura da ?gua,
intensidade e dire??o das correntes, ondas e turbidez), meteorol?gicos (precipita??o
pluviom?trica, temperatura do ar, umidade do ar, ventos e press?o barom?trica) do canal de
acesso ao Porto de Cabedelo/PB e sua bacia de evolu??o (local onde os navios atracam),
incluindo ainda ferramentas do Sensoriamento Remoto (imagens Landsat 7 ETM+, 2001),
para que as imagens e os resultados obtidos sejam integrados em Sistemas de Informa??o
Geogr?fica e utilizados na elabora??o de medidas que visem ? prote??o ambiental de ?reas
sob influ?ncia de instala??es desse porte, servindo como subs?dio para elabora??o de um
plano de conting?ncia em casos de derrames de ?leo na regi?o. Como principais resultados
destacam-se as t?cnicas de aquisi??o de dados hidroac?sticos utilizando em conjunto
levantamentos batim?tricos de alta e baixa frequ?ncia. A partir disso, foram elaboradas cinco
cartas batim?tricas no padr?o da Diretoria de Hidrografia e Navega??o - DHN, apresentando a
profundidade em metros, na escala de 1:2.500 (Bacia de Evolu??o e Canal de Acesso ao Porto
de Cabedelo), onde observa-se em grande extens?o poss?veis arenitos praiais que dificultam a
movimenta??o das embarca??es na ?rea do porto, podendo provocar colis?es, encalhe e
vazamentos de ?leo. A partir do digrama de dispers?o dos vetores de correntes, pode-se
observar como a corrente de mar? sofre uma canaliza??o e com sentido bidirecional
provocado pelo efeito da mar? (vazante e enchente) na bacia de evolu??o do Porto de
Cabedelo, no sentido NW-SE e que a maior velocidade das correntes ocorre na baixa-mar. A
caracteriza??o meteorol?gica referente ao per?odo de 28/02 a 04/07/2010 apresentou valores
dentro das m?dias esperadas para a regi?o de estudo. A integra??o de produtos multidados
(mapas digitais e imagens de sensores remotos), mostrou-se eficiente para a caracteriza??o
geomorfol?gica submersa da ?rea estudada, alcan?ando o intuito de discriminar e real?ar
estruturas submersas, antes n?o percept?veis nas imagens
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The influence of sediment characteristics on the abundance and distribution of E. coli in estuarine sedimentsWyness, Adam James January 2017 (has links)
Microbiological water quality monitoring of bathing waters does not account for faecal bacteria in sediments. Intertidal deposits are a significant reservoir of faecal bacteria and this indicates there is a risk to human health through direct contact with the sediment, or through the resuspension of bacteria to the water column. This project investigated factors influencing the relative abundance of faecal indicator organisms (FIOs) in intertidal estuarine sediments. The effects of physical, biogeochemical and biological sediment characteristics, environmental variables and native microbial communities were explored through field campaigns on the Ythan and Eden estuaries, Scotland. The contributory role of sediments to adverse water quality was investigated by combining FIO abundance and measurements of sediment stability. The importance of strain and sediment characteristics in the adhesion of E. coli to suspended sediments was also examined using laboratory experiments. E. coli concentrations up to 5.9 log₁₀ CFU 100 g dry wt⁻¹ were observed, confirming that intertidal sediments are an important reservoir of faecal bacteria. The variability of E. coli abundance in estuarine sediments was successfully explained with multiple stepwise linear regression (Adjusted R² up to 87.4) using easily-obtainable measurements of sediment characteristics and environmental variables, with variability most heavily influenced by salinity and particle size gradients. Native microbial community population metrics and community constituent composition correlated with environmental gradients, but did not influence FIO abundance. The amount of E. coli adhering to suspended sediments ranged from 0.02 to 0.74 log₁₀ CFU ml⁻¹, and was dependant on strain characteristics and sediment type rather than zeta potential, with higher cell-particle adhesion at 2 and 3.5 PSU than 0 and 5 PSU. Monitoring of sediment characteristics will lead to more informed bathing water quality advisories to protect public health. Future research should focus on applying the findings here to the modelling of bacterial fate and transport on a catchment scale.
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Uptake and mobilisation of metals associated with estuarine intertidal sediment by microphytobenthic diatomsBecker, Amani Eve January 2017 (has links)
Microphytobenthos (MPB), a mixed community of microscopic, photosynthetic organisms, algae and cyanobacteria, inhabiting the top few millimetres of bottom sediment, is a key component of intertidal mudflats. It accounts for a significant proportion of estuarine primary production, forms the base of the food chain and influences sediment distribution and resuspension (through production of extracellular polymeric substances (EPS)). Diatoms dominate the microphytobenthos community in the mid-latitudes of the Northern Hemisphere. Estuarine sediments, are a sink for metal contaminants derived from fluvial, marine and atmospheric sources. Whilst metal releases to estuaries have declined in recent years due to increased regulation and declining industrial activity, metals previously discharged and which are now locked up in saltmarsh sediments remain a concern. For example, there are indications that saltmarshes are already being eroded, due to climate change related sea level rise, in some locations. This erosion may result in the redistribution of historically contaminated sediment to locations, such as the mudflats, where it is more available to biota, such as the MPB. In addition to causing redistribution, climate change effects, such as increasing temperatures and storminess, may also alter the bioavailability of metals to MPB. Increased concentrations of metals within the MPB could potentially increase their transfer to higher organisms through the food chain with potential impacts for biota. Whilst planktonic algae have been well studied with respect to metal uptake from the water column, there has been little research involving MPB and uptake of metals from sediment. The extent to which contaminant uptake by microphytobenthic algae occurs and under what conditions is therefore poorly understood. The research presented uses laboratory, mesocosm and field studies, to gain an understanding of processes governing metal bioavailability and mechanisms for uptake from sediment to the diatoms of the MPB under the complex and variable conditions of intertidal mudflats. A laboratory study using a single diatom species Cylindrotheca closterium found that uptake of cadmium (Cd) varied with sediment properties revealing the importance of sediment particle size and organic matter content in metal bioavailability to diatoms. Additionally, this study showed that the presence of diatoms altered Cd partitioning between sediment, overlying and pore water. Specifically there was an increase in Cd in the overlying and pore water when diatoms were present, indicating that diatoms mobilise metals from the sediment to the water column potentially increasing metal bioavailability to other biota. A study was conducted using an intertidal mesocosm to increase the realism of the study system and examine uptake to a natural MPB community. Diatoms were found to have higher concentrations of all the metals analysed (except tin) than other types of algae (filamentous and sheet macroalgae), confirming their importance as a study organism with respect to metal uptake and potential mobilisation through the food chain. Sediment disturbance was shown to increase metal uptake (iron, aluminium, vanadium and lead) from the sediment to algae. This is of concern due to predicted increases in storminess which are likely to increase sediment disturbance, with the likelihood that uptake of metals to diatoms will increase in the future. However, there were also indications of an antagonistic effect of temperature on disturbance, whilst disturbance increased bioavailability and uptake, increasing temperatures reduced uptake of some metals. This highlights the importance of considering the effects of multiple stressors in complex systems. Field studies showed that concentrations of some metals were related to their position on the mudflat whilst others were related to sampling date, indicating that there may be seasonal controls, such as to the presence of greater diatom biomass in spring and autumn, on metal uptake from the sediment. The research conducted has increased understanding of metal uptake to microphytobenthic diatoms from sediment and the influence they have in transferring metals from sediment to water, however the research also raises a number of new questions. For example, there appeared to be a link between sediment organic matter content and bioavailability of metals to diatoms, although the relative contribution of the diatoms, other algae, cyanobacteria and EPS to the sediment organic matter warrants further investigation. Furthermore, it has shown that the use of laboratory and mesocosm studies for this type of research can produce similar outcomes to those observed in the field but under more controlled and easily manipulated conditions, although field studies will continue to be vital in improving understanding of metals availability and transfer.
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Variabilidade Interanual e Sazonal na Comunidade de Copepoda Relacionada ao Regime de Marés em um Estuário Tropical (Rio Mucuri, Brasil) / Interannual and seasonal variability in the Copepoda community associated with the tidal cycles in a tropical estuary (Mucuri River, Brazil)Magris, Rafael Almeida 24 March 2008 (has links)
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Previous issue date: 2008-03-24 / A variabilidade interanual, sazonal e entre as fases da maré da comunidade de Copepoda no estuário do rio Mucuri (Bahia, Brasil) foi estudada. Foram coletadas amostras de plâncton em cada estação do ano por um período de cinco anos (2002-2006) em três pontos de amostragem; sendo que em um
deles, as amostragens aconteceram de acordo com o ciclo de marés (duas na enchente e duas na vazante). Dados de temperatura, salinidade, pluviosidade e vazão do rio foram obtidos. O inverno e o verão se destacaram por representarem o período seco e o chuvoso, respectivamente. A representatividade de Copepoda na comunidade zooplanctônica variou entre 40 e 63% da abundância total de espécies, e foi composta por 46 taxa, sendo dominada por espécies comuns nos ecossistemas estuarinos (Temora turbinata, Parvocalanus crassirostris, Acartia lilljeborgi, Oithona
hebes, dentre outras). Foram encontrados indivíduos em todos os estágios do ciclo de vida, exemplificando o papel do estuário na reprodução e crescimento das espécies. Para espécies estenohalinas (e.g. Notodiaptomus sp. e Thermocyclops minutus), as variações interanuais e
sazonais parecem ser mais importantes enquanto as espécies eurihalinas (a maioria das espécies dominantes) tiveram suas densidades controladas pela variabilidade entre as fases de maré. / Copepod community variability among years, seasons and tidal fluctuations at the Mucuri River estuary (Bahia, Brasil) were studied. Zooplankton samples were collected in each season for a period of five years (2002-2006) at three sampling stations; with one of the stations sampled at each tidal cycle (two neap and two flood tides). Temperature, salinity, river flow and rainfall data were obtained. Winter and summer represented the dry and wet seasons, respectively. Copepods
abundance ranged from 40 to 63% of the total zooplankton community and was composed of 46 taxa, dominated by common estuarine species such as Temora turbinata, Parvocalanus crassirostris, Acartia lilljeborgi, Oithona hebes, among others). Individuals in all of the life stages were found, exemplifying the role of the estuary in the reproduction and growth of several species. For the stenohaline species (e.g. Notodiaptomus sp. and Thermocyclops minutus), interannual and seasonal variations seems to be more important while for the euryhaline species (the majority of the dominant ones) had their densities controlled by tidal variability.
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Flowing Together: Addressing Social-Ecological Scale Mismatches for Estuary Watershed Restoration in the Whidbey Basin, Puget Sound, WAJanuary 2015 (has links)
abstract: Landscape restoration is a global priority as evidenced by the United Nations’ 2020 goal to restore 150 million hectares of land worldwide. Restoration is particularly needed in estuaries and their watersheds as society depends on these environments for numerous benefits. Estuary restoration is often undermined by social-ecological scale mismatch, the incongruence between governing units and the bio-physical resources they seek to govern. Despite growing recognition of this fact, few empirical studies focus on scale mismatches in environmental restoration work. Using a sub-basin of Puget Sound, Washington, U.S.A., I analyze scale mismatches in estuary restoration. I take a network science approach because governance networks can bridge scale mismatches. I combine quantitative social network analysis (SNA), geographic information systems (GIS), and qualitative interview analysis.
Spatial network analysis reveals several areas with weak scale mismatch bridging networks. These weak social networks are then compared to ecological restoration needs to identify coupled social-ecological restoration concerns. Subsequent study investigates jurisdictional and sectoral network integration because governance siloes contribute to scale mismatch. While the network is fairly well integrated, several sectors do not interact or interact very little. An analysis of collaboration reasons disentangles the idea of generic collaboration. Among three relationship types considered, mandated relationships contribute almost 5.5 times less to perceived collaboration productivity than shared interest relationships, highlighting the benefits of true collaborations in watershed governance. Lastly, the effects of scale mismatch on individual restoration projects and landscape level restoration planning are assessed through qualitative interview analysis. Results illustrate why human-environment processes should be included in landscape restoration planning. Social factors are not considered as constraints to restoration but rather part of the very landscape fabric to be restored. Scale mismatch is conceptualized as a complex social-ecological landscape pattern that affects the flow of financial, human, and natural capital across the landscape. This represents a new way of thinking about scale mismatch and landscape restoration in complex multi-level governance systems. In addition, the maps, network diagnostics, and narratives in this dissertation can help practitioners in Puget Sound and provide proofs of concepts that can be replicated elsewhere for restoration and broader conservation sciences. / Dissertation/Thesis / Doctoral Dissertation Geography 2015
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Estudo do equilíbrio biogeoquímico das formas de fósforo considerando sua distribuição, partição e comportamento ao longo do complexo estuarino-lagunar de Cananéia-Iguape (SP) como ferramenta para indicação de impacto ambiental / Study of Biogeochemical Balance of Phosphorus Forms Considering Their Distribution, Partion and Behavior Along The Cananeia-Iguape Estuarine-Lagoon Complex (SP) As A Tool For Environmental Impact StatementBeatriz Ferraz Scigliano 03 August 2016 (has links)
Este trabalho teve como objetivo estudar as diferentes formas do fósforo (dissolvida, particulada e sedimentar) ao longo do complexo estuarino-lagunar de Cananeia-Iguape (SP) considerando o impacto antrópico regional causado pela abertura do canal do Valo Grande, observando o processo de ciclagem biogeoquímica do fósforo na coluna d\' água e no sedimento. O sistema foi caracterizado por meio de parâmetros hidrológicos, hidroquímicos e sedimentológicos, com enfase a formas do fósforo na água (fósforo inorgânico dissolvido, fósforo orgânico dissolvido, fósforo inorgânico particulado e fósforo orgânico particulado) e sua especiação no sedimento (fósforo biodisponível, fósforo ligado à oxi-hidróxidos de ferro, fósforo ligado à apatita autigênica, fósforo ligado à fluorapatita, fósforo orgânico e fósforo total). Para tanto foram realizadas duas coletas amostrais, uma em agosto de 2014 (inverno) composta por 20 estações, e outra em maio de 2015 (outono) com 19 estações. De posse destes dados foi possível observar no complexo estuarino dois comportamentos distintos, regidos principalmente pela influência do rio Ribeira de Iguape. Os valores mais altos fósforo dissolvido (valores de PID próximos à 10 μmol L-1 em agosto de 2014 e à 5 μmol L-1 em maio de 2015) e particulado (PIP foi de aproximadamente 70 μmol g-1 em agosto de 2014 e 60 μmol g-1 em maio de 2015) indicando a influência dos materiais e água doce introduzidos no sistema via Valo Grande. No sedimento esta distribuição foi menos evidente, recebendo maior influência da granulometria e dos processos de deposição sedimentar (P-T de aproximadamente 16 μmol g-1 e P-Fe próximo à 9 μmol g-1). Existe uma grande possibilidade de a mineração contribuir antropicamente ao aporte de fosforo especialmente na forma inorgânica. No sistema estuarino como um todo as formas particuladas de fósforo tiveram valores mais elevados que as dissolvidas, indicando um processo ativo de adsorção do fósforo ao material particulado. O setor sul apresenta concentrações menores de fósforo, indicando a maior influência marinha. Este estudo caracterizou o complexo estuarino-lagunar de Cananeia-Iguape como retentor de fósforo. / This work aimed to study the different phosphorus forms (dissolved, particulate and sedimentary) along the Cananeia-Iguape estuarine-lagoon complex (SP) considering the regional anthropic impact caused by the opening of the Valo Grande channel, observing the process of biogeochemical cycling of phosphorus in the water column and sediment. The system was characterized by means of hydrological, hydrochemical and sedimentological parameters, with emphasis in phosphorus forms in water (dissolved inorganic phosphorus, dissolved organic phosphorus, particulate inorganic phosphorus and particulate organic phosphorus) and speciation in sediment (loosely sorbed phosphorus, ferric iron-bound phosphorus, authigenic apatite biogenic apatite CaCO3- bound phosphorus, detrital apatite, organic phosphorus and total phosphorus). To this end there were two sample collections, one in August 2014 (winter) with 20 stations, and another in May 2015 (autumn) with 19 stations. Based on these data two distinct behaviors were observed in the system. They are mainly governed by the influence of the Ribeira de Iguape river. The northern sector showed higher values of dissolved (values of PID near 10 μmol L-1 in August 2014 and 5 μmol L-1 in May 2015) and particulate phosphorus (PIP was approximately 70 μmol g-1 in August 2014 and about 60 μmol g-1 in May 2015), indicating the influence of materials and fresh water input into the system via Valo Grande. In the sediment this distribution was less evident, being more influenced by grain size and sediment deposition processes (P-T was approximately 16 μmol g-1 and P-Fe near 9 μmol g-1). There is a great possibility mining was the main anthropic activity that contributes to phosphorus input especially in the inorganic form. In the estuarine system as a whole, phosphorus particulate forms were higher than those dissolved, indicating an active dissolved phosphorus adsorption process on the particulate material. The southern sector has lower phosphorus concentrations, indicating the greater marine influence. This study characterized the Cananeia-Iguape estuarine-lagoon complex as phosphorus retainer.
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Dinâmica de sedimentos coesivos em um estuário altamente estratificado: rio Araranguá, SC / Dynamic of cohesive sediment at stratified estuary: Araranguá River, SCMariana Afonso Abade Couceiro 24 April 2015 (has links)
O objetivo deste estudo é compreender a dinâmica das partículas no estuário do rio Araranguá (SC) em termos de transporte em suspensão, deposição e exportação, em diferentes condições físico-químicas da água, com pH baixo (<4,5) e normal (>=7), e sob condições de regime transiente da descarga fluvial. O estuário do rio Araranguá é classificado como altamente estratificado e dominado pela descarga fluvial. Um aspecto fundamental nos processos que controlam a dinâmica de materiais em suspensão no estuário é a atividade de lavra e beneficiamento do carvão, que gera uma drenagem ácida no rio Mãe Luzia. O seu pH baixo (˜3) indica que o processo de floculação é intensificado no interior do estuário. Com o objetivo de melhor entender a hidrodinâmica do estuário, um modelo tridimensional foi implementado para a região. O modelo foi calibrado e validado com dados observados. Simulações com diferentes picos de descarga fluvial (100, 400, 700 e 1000 m3.s-1) e baixa descarga (30 m3.s-1) foram realizadas. Para calcular o transporte do material particulado em suspensão foi desenvolvido um modelo Lagrangeano da trajetória da partícula. O modelo da trajetória utiliza os resultados do modelo hidrodinâmico e a velocidade de decantação das partículas. O estuário respondeu rapidamente às variações da descarga fluvial. A cunha salina foi transportada para fora do estuário durante os picos de 700 e 1000 m3.s-1. A descarga fluvial é o fator dominante no controle da intrusão da salinidade no estuário e, em condições de baixa descarga, o transporte advectivo de sal é dominado pelo termo dispersivo da circulação gravitacional. O tempo de residência médio das partículas no estuário foi menor em condições de pH baixo. A exportação das partículas aumentou com o aumento da descarga fluvial (pico de 1000 m3.s-1), sendo que 27% e 30% foram exportadas para a plataforma interna durante os experimentos com pH baixo e pH normal, respectivamente. A região de deposição das partículas indica que com a diminuição do pH, as partículas passam a depositar mais à jusante no estuário. O evento de descarga de 1000 m3.s-1 não foi capaz de remover a grande maioria das partículas do estuário, mas foi responsável por redistribuir as partículas ao longo do médio estuário, onde se depositaram em condições favoráveis com baixas velocidades e ausência de salinidade. O trabalho demonstra que apesar da alta estratificação do estuário, a acidez de suas águas, seu padrão de circulação, com baixas velocidades e a presença da cunha salina, possuem um papel fundamental no transporte das partículas, resultando em maior potencial de retenção do material em suspensão no estuário do rio Araranguá. / The present study assessed the dynamics of particles of the Araranguá (SC) river estuary in terns of suspended transport, deposition and exportation in different conditions of physical-chemical of water, with low (<4,5) and normal pH (>=7), and transient of river discharge conditions. The Araranguá river estuary is a highly stratified flash-flood dominated. The river basin of the Mãe Luzia river, one of the main tributaries of the Araranguá river, is performed the activity of mining and coal processing, wich generates an acidic drainage. Its low pH indicates that flocculation process is intensified in estuary inner. With the objective of better understanding the estuarine processes, a three-dimensional hydrodynamics model was implemented. The model was calibrated and verified using observational data. Simulations were conducted with freshet peak ranged over 100, 400, 700 and 1000 m3.s-1. Lagrangian particle tracking algorithms was developed to represent the suspended particle transport at estuary. The particle tracking used the montion resulting from hydrodynamics model and the particle settling velocity. The estuary responded quickly the river discharge variations. During the pulse event the velocities at water column were unidirectional down-estuary is shown the barotropic dominates over baroclinic component. During the highest flash flood event (700 and 1000 m3.s-1) the salt water was pushed out of the estuary. The river discharge is a dominating factor affecting the salinity intrusion in the estuarine system and under low discharge conditions the advective salt transport is dominated by dispersive term of gravitational circulation. The mean residence time of the particles was lowest in pH low conditions. The particles export is great as the river discharge is rising (1000 m3.s-1) with 27% and 30% exported to inner shelf during the experiments with low and normal pH, respectively. The particles deposition local indicates that with the pH decrease the particles become to be deposited further downstream. The discharge event of 1000 m3.s-1 was not able to remove all particles out, but was response to redistribute the particles along of the meddle estuary, where settling in favorable conditions at low velocities and absence of salinity. The study shows that although high stratification of estuary, the acidity of water, the pattern of circulation, at low velocities, and the salt wedge presence play a fundamental role in the transport of particle matter resulting in increased the potential retention of suspended matter in the Araranguá river estuary.
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Determinação da história deposicional recente do Alto Estuário Santista, com base nos teores de metais e na suscetiblidade magnética dos sedimentos / Determination of the recent depositional history of Santos and São Vicente Estuary, based on heavy-metal contents and magnetic susceptibility of the sedimentsMarina Midori Fukumoto 27 September 2007 (has links)
O Sistema Estuarino de Santos e São Vicente, localizado na porção central do litoral do Estado de São Paulo, abriga o mais importante complexo industrial costeiro do País, o Complexo Industrial de Cubatão, e o maior porto brasileiro, o Porto de Santos. Os objetivos deste trabalho foram o estudo do histórico da contaminação da área por metais pesados e a avaliação da aplicabilidade da suscetibilidade magnética na detecção de anomalias geoquímicas. Foram estudados três testemunhos próximos a fontes pontuais de poluição. A taxa de sedimentação foi determinada pelo método do 137Cs, a suscetibilidade magnética foi medida por um perfilador Bartington MS2C e o teor de metais foi analisado em ICP-OES. Os teores de Pb, Cu, Cr e Zn apresentaram uma tendência de aumento em direção ao topo dos testemunhos, mas os maiores teores não ocorrem na superfície, e sim a alguns centímetros de profundidade. A correlação entre os teores de Pb, Cu, Cr e Zn e a suscetibilidade magnética indicou a aplicabilidade desta na avaliação preliminar da qualidade dos sedimentos. O aporte desses metais pode ser associado a diversas fontes antrópicas relacionadas ao desenvolvimento urbano-industrial da região, como atividades industriais e portuárias e disposição irregular de resíduos sólidos e esgoto. / The Santos and São Vicente Estuary, located in the central portion of the coast of São Paulo state, has the most important industrial area of Brazilian coast, the Cubatão industrial complex, and the largest Brazilian harbour, the Santos harbour. The aims of this work were the study of the contamination history of the area by heavy metals and the applicability of magnetic susceptibility to detect geochemical anomalies. Three sediment cores were collected near polluted sites. The sedimentation rate was determined by 137Cs method, magnetic susceptibility was measured by a Bartington MS2C sensor and metal contents was analyzed by ICP-OES. Pb, Cu, Cr and Zn contents presented high values near the top of the cores. The highest values don?t occur in the surface, but in some centimeters of depth. The correlation between Pb, Cu, and Zn contents and magnetic susceptibility shows the applicability of magnetic susceptibility in the preliminary evaluation of sediment quality. The input of these metals can be associated to different anthropic sources, linked to urban and industrial development of the area: industrial and harbour activities and irregular waste and sewage disposal.
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