The problem of how sand and mud was distributed downslope, within linked alluvial-brackish water-marine shoreline systems of an extensive clastic wedge is addressed here. The Iles Clastic wedge accumulated over a time period of a few million years (my), and its component high-frequency regressive-transgressive sequences have a duration of a few 100 thousand years (ky). The sediment partitioning study provides insight into where the thickest sandstones and mudstones were located, and generates a model that can be applied to improving the management of hydrocarbons or water resources. A 300 km 2-D study transect across the Iles Clastic Wedge in SW Wyoming and N Colorado included subsurface well log information and outcrop stratigraphic columns. This information was used to correlate high-frequency sequences across several hundred kilometers, characterize depositional processes from proximal to distal reaches, develop a sediment partitioning model, and understand the role of the likely drivers in the development of the wedge and its internal sequences. The main results of this study are: (1) The Iles Clastic Wedge spans 3 my (500 m thick) and is composed internally of 11 sequences of 200-400 ky, each of which have significant regressive-transgressive transits of up to 90 km. Sediment partitioning analysis shows that within the regressive limb of the large wedge, the component regressive compartments tend to thicken basinwards, whereas transgressive compartments thicken landwards. This geometry is driven by preferential erosion in proximal areas during regression, bypassing much sediment to the marine shorelines, and transgressive backfilling into proximal areas previously eroded more deeply. (2) The greatest concentration of sands tends to be located in the proximal fluvial and estuarine facies of the transgressive compartments and within the medial shoreline/deltaic facies of the regressive compartments. (3) As the high-frequency sequences developed, the effectiveness of basinward sand partitioning reaches a maximum value near the peak regression level of the wedge, reflecting stronger erosion and sediment bypass during this times. (4) The development of the Iles Clastic Wedge was influenced by both tectonic and eustatic drivers, with important tectonic control in the upstream reaches. On a 4th-order timescale, the Iles Wedge internal sequences were likely influenced mainly by eustasy. / text

<p>När en kommersiell hamn byggs ut fordras omfattande muddringsarbete för att säkerställa ett brukligt djup för sjöfart. Då stora delar av muddermassorna ofta är förorenade av tungmetaller och miljögifter krävs särskilt omhändertagande av dessa. Traditionella omhändertagningsalternativ består av att deponera massorna på särskild avsedd plats på land eller tippa till havs, något som inte tillåts för förorenade sediment. En relativt ny metod är stabilisering/solidifiering (S/S) som innebär att muddermassorna behandlas med ett bindemedel för att sedan kunna användas som fyllnadsmaterial i exempelvis kajkonstruktioner. Dessa alternativ behöver noga vägas mot varandra med hänsyn till ekonomiska och miljömässiga aspekter. Föreliggande studie undersöker  ventuella brister i de ekonomiska värderingar som genomförts inför  utbyggandet av Oxelösunds hamn. Vidare genomförs en begränsad cost-benefit analys (CBA) för att värdera alternativen utifrån emissionsnivåer till luft och vatten. Resultatet visar att S/S innan nyttiggörande är det samhällsekonomiskt mest attraktiva alternativet.</p> / <p>When a commercial port is expanding its activities there is need for dredging to secure a safe depth for water borne traffic. The sediments are to a large extent contaminated by metals and toxins which calls for certain treatment. Traditionally sediments have either been disposed of at a specific location on land or dumped at sea; the latter is however not permitted by law. A relatively new method is stabilization/solidification (S/S) which means that the sediments are treated using a solidifying agent after which it is possible to use the dredged materials as filling in construction of jetties. These alternatives need to be carefully compared with respect to economical and environmental aspects. This thesis investigates the potential shortcomings of conducted economical evaluations prior to the expansion of Oxelösund port. Further, a limited cost-benefit analysis is conducted to evaluate the alternatives with respect to emissions of contaminants to air and water. The results show that S/S before utilization of the dredged materials is the most attractive alternative from an economical point of view.</p> / STABCON

Paleoclimatic archives, such as lake sediments, extend our understanding of terrestrial and aquatic ecosystem dynamics in relation to climate variability beyond the period covered by instrumental data. In this context, annually laminated (i.e. varved) lake sediments are particularly valuable, as they offer high temporal resolution and undisturbed sediment. However, in order to extract reliable climate information from lake sediments, a careful calibration with the processes controlling the sediment formation is essential. This thesis combines limnological and paleolimnological data from a varved, boreal lake in northern Sweden (Nylandssjön, Nordingrå) collected over different time scales. The main aim of the thesis is to gain a more refined insight into which processes are reflected in the sedimentary diatom assemblage. More specifically, sequential sediment trap records were coupled with physical, chemical and biological lake monitoring and environmental data for comparison and validation with the varved sediment record. The main result of the thesis is that timing, succession and inter-annual variability of key limnological and environmental processes (e.g. ice-cover duration, lake over-turn or catchment run-off) are of major importance for the sedimentary diatom assemblage formation. Continuous monitoring of physico-chemical parameters over three consecutive years identified varying winter air temperature as a major factor influencing in-lake processes and hence the diatom record. Timing of lake over-turn and catchment run-off seemed to be the driver for monospecific diatom blooms, which are reflected in the annual sediment signal. The integrated annual diatom signal in the sediment was dominated by spring or autumn blooms, resulting either from a Cyclotella glomerata dominated spring bloom after relatively warm winter conditions, or a Asterionella formosa dominated autumn bloom after relatively cold winter conditions. The analysis of the diatom stratigraphy in the varved sediment over several decades corroborated the importance of climatic variables (late winter air temperature and NAO), even though the variables with the most predictive power for variance in the diatom data were associated with sediment composition (C, N and sedimentation rate) and pollution (Pb and Cu). Overall, the analysis of the drivers of inter-annual and decadal diatom assemblage fluctuations emphasizes the importance of winter air temperature, indicating that weather extremes may be disproportionately represented in annual sediment records in contrast to nutrient concentrations or sedimentation rate.

Nos connaissances et notre compréhension de la dynamique sédimentaire des plages macrotidales sont encore limitées de nos jours en raison d'un manque de données lié à la plus faible proportion de ces plages à l'échelle mondiale. Trois plages macrotidales à barres et à bâches du littoral de la Côte d'Opale dans le Nord de la France ont été choisies pour mener cette étude. Elle se base sur trois approches différentes visant à caractériser (1) le régime tidal et les conditions hydrodynamiques, (2) la morphologie de la zone intertidale et (3) les flux sédimentaires longitudinaux (FL) et transversaux (FC) dans diverses conditions tidales et énergétiques. Le transport a été mesuré dans la zone proche du déferlement à l’aide de pièges à sédiment de type Kraus (1987) permettant de caractériser le débit solide à plusieurs niveaux au dessus du fond au cours de conditions d'agitation faibles à modérées (Hs < 1 m). Malgré une uniformité des flux le long de la plage, les phénomènes de vidange des bâches par l’intermédiaire de chenaux perpendiculaires au trait de côte permettent l’introduction de volumes de sédiment significatifs, augmentant localement le FL. La distribution des flux à travers l’estran présente, quant à elle, une décroissance nette du bas de plage vers le haut de plage. Les mesures simultanées de FL et de FC ont démontré que le FC dirigé vers le haut de plage et la résultante du FC sont dans la plupart des cas supérieurs aux FL en raison de la plus forte intensité des vitesses de courant oscillatoire. Ces résultats mettent en évidence des mouvements significatifs de volume de sable à travers la zone intertidale à l’échelle de la mesure, ce qui influence fortement la morphodynamique de la plage. L’ensemble de la zone intertidale est toutefois apparue relativement stable, avec des changements plus significatifs à court terme qu'à plus long terme. Les mesures de transport ont permis de mettre en lumière le rôle fondamental des bâches dans la dynamique des plages macrotidales. Ces dépressions inter-barres sont en effet responsables de la canalisation du sédiment le long du rivage, limitant ainsi les transports sédimentaires transversaux et par conséquent la migration des barres intertidales. Il est vraisemblable que le temps de résidence et l'intensité des processus hydro-sédimentaires jouent un rôle prépondérant dans la dynamique des barres intertidales. Les mesures ont également été comparées avec plusieurs estimations du transport sédimentaire issues de modèles numériques et morphodynamiques. Bien que les flux calculés surestiment en général le transport mesuré, certaines formules semblent plus adaptées pour déterminer le FL dans la zone de levée. / Our knowledge and understanding of the sediment dynamics of sandy macrotidal beaches is still limited by a lack of data from these macrotidal environments. This limitation is due to the relatively small proportion of macrotidal coasts in the world. Three sandy beaches on the coast of Northern France were chosen to conduct this study. Three scientific approaches were used: 1) characterization of tidal and waves energy conditions using wave and current meters deployed on the foreshore; 2) beach morphology survey and 3) estimation of longshore (FL) and cross-shore (FC) sediment transport using streamer traps similar to those designed by Kraus (1987). Sand transport was measured about 1 m water, next to the breaker zone and either in the shoaling zone or in the surf zone; under low to moderate waves energy conditions (Hs < 1 m). In spite of a low longshore variability in sediment transport due to a high degree of hydrodynamic uniformity along the shore, runnel drainage can locally increase sediment transport rates. Cross-shore distribution appeared to be more variable as sediment transport decreased from the lower to the upper part of the beach. Onshore, offshore and longshore sediment transport measured simultaneously showed that under various energetic conditions, FC appeared to be generally higher than FL. Although net littoral drift is directed towards the Belgian coast, these results suggest that significant volumes of sand move across the intertidal zone. These significant volumes of sand most likely have a strong influence on the morphodynamics of the beach. Daily topographical survey has shown little morphological variations while sediment transport rates appeared very variable and very significant, especially during the highest wave energy conditions. Sediment transport measurements across the foreshore highlight the important role played by inter-bar troughs in the morphodynamics of macrotidal beaches. Higher bed roughness in these depressions is responsible for an increase in sediment resuspension through the water column. Suspended transport is therefore favoured in troughs and hinders the cross-shore sediment transport, which is responsible for the bar migration across the intertidal zone. Morphological changes are dependent of the time residence of the hydrodynamic zones, but the morphodynamics of the intertidal bars appear to be strongly controlled by the amplitude of the incident waves. FL were also compared with calculated data computed using from numerical and morphodynamic model. Although computed transport rates are generally higher than in situ measurements, it appears that some formulae provide better estimate of FL, especially in the shoaling zone

L’objectif de ce travail est d’étudier la dynamique du bouchon vaseux, ainsi que la dynamique saline, dans l’estuaire de la Gironde. La stratégie adoptée consiste à examiner, par le biais du modèle de simulation SIAM-3D, l’impact du paramétrage hydro-sédimentaire, du débit fluvial et de la bathymétrie, sur le comportement des sédiments et sur l’évolution de la salinité. L’effet de la vitesse de chute sur la dynamique sédimentaire est l’un des cas étudiés ; son impact sur la distribution des suspensions est considérable. Ainsi, la diminution de ce paramètre entraîne l’homogénéisation de la concentration sur la verticale, mais aussi l’étalement du bouchon vaseux et l’évacuation d’une masse de sédiment hors de l’estuaire. Nous avons également mis en évidence lors d’une période de débits moyens ou faibles précédée par une crue, la partition du bouchon vaseux simulé en deux masses turbides, l’une remonte l’estuaire alors que l’autre se maintient en aval. La dynamique saline a été étudiée, entre autres, par l’analyse des gradients de salinité, calculés dans l’estuaire aval et en situation de forts débits. On observe, la diminution de ces gradients avec l’augmentation de l’intensité de la marée à l’échelle des cycles vives-eaux/mortes-eaux, toutefois, de fortes valeurs sont maintenues lors de la phase d’augmentation de cette grandeur à l’échelle de la marée. D’autres résultats ont permis de vérifier la capacité du modèle à simuler des dynamiques sédimentaires observées in-situ ; on peut citer entre autres, le détachement du bouchon vaseux de la rive gauche dans l’estuaire aval et son transfert vers la rive droite, en situation de forts débits. Afin d’évaluer l’impact de l’évolution du fond des fleuves de 1959 à 2002 sur l’hydrodynamique et les dynamiques sédimentaire et saline, nous avons comparé deux simulations, l’une effectuée avec l’ancienne bathymétrie de 1959, l’autre avec la nouvelle bathymétrie de 2002. Les résultats montrent l’augmentation de la masse sédimentaire dans les fleuves avec la bathymétrie de 2002 comparée à celle de 1959, ainsi que la hausse de la salinité dans la Garonne et l’amplification de la marée dans la Dordogne. Ces résultats sont en accord avec les mesures et observations in-situ. / The aim of this work is to study the turbidity maximum dynamics as well as the salinity dynamics in the Gironde estuary. The adopted strategy consists in analysing, by means of the SIAM-3D simulation model, the impact of hydro-sedimentary parameters, the fluvial flow and the bathymetry on sediment behaviour and salinity evolution. The effect of settling velocity on sediment dynamics is one of the studied cases; its impact on suspended sediment distribution is goodly. Thus, the diminution of this parameter leads to homogenisation of concentration in water column, but also spreading the turbidity maximum and evacuation of a sediment mass outside the Gironde estuary. We gave also prominence to the division of the turbidity maximum into two parts during low or mean water flow preceded by peak high water discharge, one of the parts migrates upstream whereas the other remains downstream. We studied the salinity dynamics, among others things, by means of analysing the calculated salinity gradients in the lower estuary during high water discharge. We observe the decrease of these gradients with increase of the tide intensity on a scale of spring tides/neap tides cycles, however, on a scale of tide, these gradients reach high values during the augmentation phase. Others results indicate the model capacity to simulate in-situ observations of the sediment dynamics; for example, the detachment of turbidity maximum from the left bank in the lower estuary and its transfer to the right bank during high water discharge. In order to evaluate the impact of the bed river evolution from 1959 to 2002 on hydrodynamics, sediment and salinity dynamics, we compared two simulations performed using the former (1959) and recent (2002) bathymetries. The results demonstrate that the sediment mass increase in the rivers with recent bathymetry, as well as, the salinity in the Garonne river and the tide amplitude in the Dordogne river. These results are in accordance with the in-situ measures and observations.

Os sedimentos, pela sua capacidade de acumular compostos, têm grande importância na avaliação do nível de contaminação e poluição dos ecossistemas aquáticos continentais. Este trabalho tem como objetivo avaliar a qualidade do sedimento de um reservatório urbano (Reservatório Guarapiranga, SP, Brasil), quanto ao teor de metais fracamente ligados ao sedimento usando valores-guia de qualidade como parâmetro de comparação; e verificar a possível heterogeneidade dos metais contidos neste sedimento em um gradiente espacial horizontal. Foram amostrados onze pontos ao longo do eixo principal do Reservatório Guarapiranga, com a utilização de coletor tipo Ambhül e Bührer, em 05/10/2006 e 27/04/2007. As variáveis analisadas foram: matéria orgânica total, para cálculo do carbono orgânico total (COT); sulfeto volatilizável por acidificação (SVA), metais simultaneamente extraídos (MES), pH, EH, temperatura, oxigênio dissolvido, profundidade e granulometria. Pela relação molar (&sum;[MES] - [SVA])/ COT, critério de qualidade de sedimento estabelecido pela U.S.EPA, o sedimento não apresentou toxicidade provável à biota, ou seja, os metais presentes não estão biodisponíveis. As concentrações de SVA e de matéria orgânica encontradas no sedimento e as frações granulométricas silte e argila se mostraram como importantes fases complexadoras dos metais. Segundo os Valores-Guia de Qualidade de Sedimento, estabelecidos pelo Conselho Canadense do Ministério do Meio Ambiente (CCME), em outubro, a maioria dos pontos amostrados encontrou-se acima do intervalo com possíveis efeitos adversos à biota (PEL: Probable Effect Level), em relação a concentração de Cd, Cu e Ni; e em abril a maioria dos pontos amostrados apresentou concentrações acima de PEL para Cu e Cr. A maioria dos pontos amostrados teve concentrações dos metais Cd, Cu, Ni e Zn acima do Valor de Referência Regional (VRR) para sedimentos da Bacia do Rio Tietê, em outubro; e concentrações acima de VRR para Cd, Cu, Cr e Zn, em abril. Em relação à heterogeneidade espacial horizontal, pode-se dividir o reservatório em dois compartimentos, que diferem, de acordo com a PCA, quanto aos teores dos metais Cd e Cu e a profundidade, sendo a região com maiores concentrações de metais a que engloba a captação de água para abastecimento público. Os elevados teores de metais, apesar de este trabalho sugerir que não estão biodisponíveis, reforçam a necessidade do contínuo monitoramento não apenas da qualidade do sedimento, mas também da massa de água, principalmente por se tratar de um reservatório destinado ao abastecimento público para 20% da população da cidade de São Paulo. / Sediments are very important in assessing contamination and pollution level in continental aquatic ecosystems, because of their capacity of accumulating compounds. The objective of this project was to asses sediment quality of a tropical urban reservoir (Guarapiranga Reservoir, São Paulo State, Brazil), related to the level of weakly-bounded metals by using different sediment quality guidelines as reference; and to check possible space heterogeneity of these metals in a horizontal space gradient. Eleven sample stations along the main axis of Guarapiranga Reservoir were sampled by means of an Ambhül and Bührer collector, in October/05/2006 and April/27/2007. The variables analyzed were: total organic matter for calculation of the total organic carbon (TOC), acid volatile sulfide (AVS), simultaneously extracted metals (SEM), pH, EH, temperature, dissolved oxygen, depth and granulometry. According the molar relation (&sum;[SEM] - [AVS])/ TOC, sediment quality guidelines suggested by U.S.EPA, sediment did not show probable toxicity, in other words, metals were not bioavailable. The AVS, organic matter concentrations and clay silt percentiles showed be important phases of metal complexation, in sediment. According to sediment quality guidelines suggested by Canadian Council of Ministers of Environment (CCME), in October, most of sampling stations presented metal concentration above PEL (Probable Effect Level) for Cd, Cu and Ni; and in April, most of sampling stations presented concentration above PEL for Cu and Cr. Most of sampling stations presents Cd, Cu, Ni and Zn concentrations above the Regional Reference Values (RRV) for Tietê River Basin sediments, in October and concentrations above (RRV) for Cd, Cu, Cr and Zn, in April. In relation to space heterogeneity, the reservoir can be divided into two parts, which are different, according PCA, because of Cd and Cu concentrations and depth, being the region with higher concentrations that from where water is taken in for public supply. The high metal levels, eventhoug the present work indicates no- bioavailability, reinforce the necessity of continuous monitoring of sediment and water quality, especially due to the fact that this reservoir is used to supply 20% of the population from São Paulo city.

A deriva litorânea é estudada no litoral sul do Espírito Santo através de diferentes técnicas: distribuição de Minerais Pesados (MP); modelo conceitual Análise de Transport de Sedimento (Sediment Trend Analysis - STA), através da variação de parâmetros texturais do sedimento; dados de clima de onda entre 1997 e 2010 do modelo global WaveWatch III propagados para a zona costeira através do modelo Delft-3D, fornecendo parâmetros necessários para as equações de deriva; e imagens de satélite e fotografias aéreas para avaliar a variação espaço-temporal da morfologia costeira. O modelo STA mostrou-se confiável apenas nos dois setores ao norte, enquanto nos demais os resultados foram mascarados por altos teores de MP e/ou carbonato e a entrada de outras fácies no sistema; as equações representaram bem a variação da morfologia costeira na área de estudos. De maneira geral, os setores ao sul apresentaram transporte longitudinal para sul, e os setores ao norte, para norte, fato relacionado à batimetria local. A orientação da linha de costa auxiliou na compreensão dos fenômenos erosivos, pois em sua maioria estão orientados no sentido NEN, formando 45º com as ondas dos setores de ESE e SE. / Longshore drift is studied in the southern portion of Espírito Santo through different techniques: Heavy Minerals (HM) distribution; the conceptual model Sediment Trend Analysis (STA) by sediment textural parameters fluctuation; wave climate data between 1997 and 2010 from WaveWatch III propagated to the coastal zone through Delft-3D model, providing the required data for longshore drift equations; and satellite images and aerial photograph to survey time-space coastline variations. The STA model appears to be trustworthy only within the northern sectors, as high HM and/or carbonate content and different facies input into the system may mask the results. Broadly speaking, the southern sectors showed longshore transport southward, while northern sectors showed northward longshore transport, which is related to local bathymetry. Shoreline azimuth helped understanding the location of erosive zones, since most of them are turned NEN, 45o with ESE and SE wave sectors.

Chemical weathering of silicate rock consumes atmospheric CO2 and supplies the oceans with cations, thereby controlling both seawater chemistry and climate. The rate of CO2 consumption is closely linked to the rate of CO2 outgassing from the planetary interior, providing a negative feedback loop essential to maintaining an equable climate on Earth. Reconstruction of past global temperatures indicates that a pronounced episode of global cooling began ~50 million years ago, coincident with the collision of India and Asia, and the subsequent exhumation of the Himalayas and Tibet. This has drawn attention to the possible links between exhumation, erosion, changes in silicate weathering rates, and climate. However, many of the present-day weathering processes operating on the continents remain debated and poorly constrained, hampering our interpretations of marine geochemical archives and past climatic shifts. To constrain the controls on silicate weathering, this thesis investigates the lithium (Li) isotopic composition of river waters, suspended sediments and bed load sediments in the Alaknanda river basin, forming the headwaters of the Ganges. Due to the large fractionation of Li isotopes in the Earth’s surface environment, Li is sensitive to small changes in silicate weathering processes. As a consequence of the pronounced gradients in climate (rainfall and temperature) and erosion across the basin, the river waters show large variations in their Li isotopic composition (δ7Li), ranging from +7.4 to +35.4‰, covering much of the observed global variation. This allows a detailed investigation of the controls on Li isotope fractionation, and by extension silicate weathering. The Li isotopic composition is modelled using a one-dimensional reactive transport model. The model incorporates the continuous input of Li from rock dissolution, removal due to secondary mineral formation, and hydrology along subsurface flow paths. Modelling shows that the Li isotopic variations can be described by two dimensionless variables; (1) the Damköhler number, ND, which relates the silicate dissolution rate to the fluid transit time, and (2) the net partition coefficient of Li during weathering, kp, describing the partitioning of Li between secondary clay minerals and water, which is primarily controlled by the stoichiometry of the weathering reactions. The derived values of the controlling parameters ND and kp, are investigated over a range of climatic conditions and on a seasonal basis, shedding light onto variations in the silicate weathering cycle. In a kinetically limited weathering regime such as the Himalayan Mountains, both climate and erosion exert critical controls the weathering intensity (the fraction of eroded rock which is dissolved) and the weathering progression (which minerals that are being weathered), and consequently the fractionation of Li isotopes and silicate weathering in general. Modelling of the Li isotopic composition provides an independent estimate of the parameters which control silicate weathering. These estimates are then used to constrain variables such as subsurface fluid flux, silicate dissolution rates, fluid transit times and the fraction of rock which is weathered to form secondary clay minerals. The simple one-dimensional reactive transport model therefore provides a powerful tool to investigate the minimum controls on silicate weathering on the continents.

Este trabalho teve como objetivo principal a utilização de duas variantes da técnica analítica de fluorescência de raios X, dispersiva em energia - EDXRF e reflexão total TXRF, na determinação de Pb em amostras de águas superficiais e subterrâneas, e em sedimentos em suspensão e de fundo. Cinco amostras de cada matriz foram coletadas em uma área contaminada, nas proximidades da desativada fábrica de baterias Indústria Acumuladores Ajax Ltda., localizada no km 229 da rodovia Jaú-Ipaussu, em Bauru, SP. As variantes EDXRF com pré-concentração com APDC e medida direta por TXRF mostraram resultados satisfatórios na determinação de Pb em soluções-padrão e amostra certificada de água natural SRM1640, produzida pelo NIST, obtendo-se concentrações compatíveis com os valores esperados. A primeira técnica resultou em limite de detecção da ordem de 0,70 mg L-1, com tempo de análise de 300 s, melhor que a segunda técnica (4,46 mg L-1), em 200 s. Estas duas variantes também foram utilizadas para outros elementos químicos, como o Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn e Br, onde a EDXRF mostrou também melhores limites de detecção para todos os elementos. Para Ni, Cu e Zn, importantes na indústria de baterias, foram encontrados os limites de 0,34 - 0,27 e 0,24 mg L-1, respectivamente, enquanto que por TXRF foram encontrados os valores ao redor de 1 mg L-1. Na validação destas duas metodologias para análise de água, a EDXRF mostrou resultados mais próximos aos valores esperados, enquanto que por TXRF foram superestimados na maioria das vezes, com exceção para As, Se e Pb. Este erro foi devido a uma interferência espectral ocasionada provavelmente pela presença dos elementos Ti ao Zn nos componentes metálicos do arranjo experimental, ausentes no suporte refletor de quartzo, colimador do detector ou solução do padrão interno. Sem a eliminação dessa interferência, os resultados obtidos por TXRF para estes elementos, com exceção para As, Se e Pb, só podem ser utilizados como qualitativos. Para análise de sedimentos em suspensão foi utilizada a técnica de EDXRF, assumindo a amostra como filme fino, atingindo limite de detecção da ordem de 2 mg g-1 para Pb, enquanto que para o Cu e Zn o limite de detecção foi da ordem de 5 mg g-1, em 300 s. Para sedimento de fundo foi utilizada a mesma técnica, mas admitindo a amostra como espessa, corrigindo-se o efeito matriz através do fator de absorção, validando-a pela análise de amostras certificadas de sedimento (SRM1646a/NIST) e solo (SRM2711/NIST). O limite de detecção para Pb ficou em torno de 2 mg g-1, e para outros elementos os limites foram de 3,07 mg g-1 para Ni, 2,12 mg g-1 para Cu e 1,50 mg g-1 para Zn, em 500 s. Com base nos valores máximos permitidos para Pb, estabelecidos pela Portaria 1469/00 e Resolução 20/1986 CONAMA, duas amostras de água mostraram-se contaminadas pelos resultados obtidos pela variante EDXRF, e quatro pelos resultados da TXRF. Para os outros elementos, apesar da interferência na TXRF, por esta técnica uma amostra de água ultrapassou o limite permissível para Cu e todas as cinco para Zn, e pela EDXRF uma amostra para Ni e Cu em água, e três para Zn. Na legislação brasileira não há limite máximo permitido para Pb e outros elementos em solos e sedimentos, e portanto foram adotados os limites TEL (Threshold Effect Level, nível limiar do efeito) e PEL (Probable Effect Level, nível provável do efeito), utilizados pela Agência Ambiental Canadense. As amostras de sedimento em suspensão mostraram concentrações de Pb menores que o limite de detecção, e das cinco amostras de sedimento de fundo, uma amostra apresentou valor acima do limite TEL, e outra, coletada num ponto bem ao lado da fábrica, acima do limite PEL. Para os outros elementos Ni, Cu e Zn, nenhuma das amostras de sedimento em suspensão ou de fundo não ultrapassaram os limites TEL. / This study had as main objective the use of two variants of the analytical technique of X-ray fluorescence, energy dispersive - EDXRF and total reflection - TXRF, for the determination of Pb in superficial and underground water and in suspended and bottom sediment samples. Five samples of each matrix were collected in a contaminated area near the closed battery plant, Indústria de Acumuladores Ajax Ltd., located on km 229 of the Jaú-Ipaussu highway, near the city of Bauru in São Paulo State, Brazil. The two variants – EDXRF with preconcentration with APDC and TXRF direct measurement – had shown satisfactory results in the determination of Pb in standard solutions and certified natural water sample SRM1640/NIST, obtaining compatible concentrations with the expected values. The first technique resulted in a 0.70 mg L-1 limit of detention, with 300 s analysis time, and the second one 4.46 mg L-1 in 200 s. These two variants were also used for other chemical elements, such as Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn and Br. EDXRF also showed better limits of detection for all the elements. For Ni, Cu and Zn, important in the industry of batteries, the limits of 0.34, 0.27 and 0.24 mg L-1, respectively, were found, while with TXRF the values of around 1 mg L-1 were achieved. In the validation of these two methodologies for water analysis, the EDXRF showed results nearer to the expected values, while with TXRF the results were overestimated most of the times, with the exceptions of As, Se and Pb. This error was due to a spectral interference caused probably by the presence of the elements Ti to Zn in the metallic parts of the experimental arrangement, absent in the quartz reflecting support, detector collimator or internal standard solution. Without the elimination of this interference, the results for TXRF for these elements, with the exceptions of As, Se and Pb, can only be used as qualitative results. For analysis of suspended sediments, the EDXRF technique was used, assuming the sample as thin film, the limit of detection of around 2 mg g-1 for Pb was reached, while that for Cu and Zn was around 5 mg g-1, in 300 s. For bottom sediments the same technique was used, but admitting the sample as thick, the matrix effect through the absorption factor was corrected, validating it for the analysis of certified samples of sediment (SRM1646a/NIST) and soil (SRM2711/NIST). The limit of detention for Pb was around 2 mg g-1 and for other elements the limits were 3.07, 2.12 and 1.50 mg g-1 for Ni, Cu and Zn, respectively, in 500 s. On the basis of the Brazilian allowed maximum values for Pb, established by Decree 1469/00 and Resolution 20/1986 CONAMA, two water samples were shown to be contaminated by the results gotten with variant EDXRF, and four by the results of TXRF. For the other elements from the TXRF results (despite the interference) one water sample exceeded the permissible limit for Cu and all the five for Zn, and for the EDXRF results one sample for Ni and Cu and three for Zn. In the Brazilian legislation there is no maximum limit allowed for Pb and other elements in soils and sediments; therefore, TEL (Threshold Effect Level) and PEL (Probable Effect Level) limits from the Canadian Environment Agency were adopted. The suspended sediment samples showed Pb concentrations lesser than the limit of detection. From the five bottom sediment samples, one sample presented a value above the TEL limit, and another one, collected in a point very close to the plant, above the PEL limit. For the other elements, Ni, Cu and Zn, none of the suspended or bottom sediment samples exceeded the TEL limits.

A deriva litorânea é estudada no litoral sul do Espírito Santo através de diferentes técnicas: distribuição de Minerais Pesados (MP); modelo conceitual Análise de Transport de Sedimento (Sediment Trend Analysis - STA), através da variação de parâmetros texturais do sedimento; dados de clima de onda entre 1997 e 2010 do modelo global WaveWatch III propagados para a zona costeira através do modelo Delft-3D, fornecendo parâmetros necessários para as equações de deriva; e imagens de satélite e fotografias aéreas para avaliar a variação espaço-temporal da morfologia costeira. O modelo STA mostrou-se confiável apenas nos dois setores ao norte, enquanto nos demais os resultados foram mascarados por altos teores de MP e/ou carbonato e a entrada de outras fácies no sistema; as equações representaram bem a variação da morfologia costeira na área de estudos. De maneira geral, os setores ao sul apresentaram transporte longitudinal para sul, e os setores ao norte, para norte, fato relacionado à batimetria local. A orientação da linha de costa auxiliou na compreensão dos fenômenos erosivos, pois em sua maioria estão orientados no sentido NEN, formando 45º com as ondas dos setores de ESE e SE. / Longshore drift is studied in the southern portion of Espírito Santo through different techniques: Heavy Minerals (HM) distribution; the conceptual model Sediment Trend Analysis (STA) by sediment textural parameters fluctuation; wave climate data between 1997 and 2010 from WaveWatch III propagated to the coastal zone through Delft-3D model, providing the required data for longshore drift equations; and satellite images and aerial photograph to survey time-space coastline variations. The STA model appears to be trustworthy only within the northern sectors, as high HM and/or carbonate content and different facies input into the system may mask the results. Broadly speaking, the southern sectors showed longshore transport southward, while northern sectors showed northward longshore transport, which is related to local bathymetry. Shoreline azimuth helped understanding the location of erosive zones, since most of them are turned NEN, 45o with ESE and SE wave sectors.