Este trabalho teve por finalidade simular a hidrodinâmica da Plataforma Continental Interna do Estado de São Paulo (PCISP) e da Plataforma Continental Média do Estado de São Paulo (PCMSP) no período de verão, em resposta às forçantes do gradiente de densidade, do vento climatológico e das marés, através da implementação do modelo numérico hidrodinâmico tridimensional Regional Ocean Modeling System (ROMS). Os experimentos realizados mostraram que os efeitos da distribuição de densidade sobre o comportamento geral da circulação na PCISP e PCMSP são secundários quando comparados à circulação induzida pela tensão de cisalhamento do vento. Os resultados apontam que na PCISP e na PCMSP a componente de velocidade paralela à costa é dominada por forçantes de frequência subinercial, como o vento climatológico e o gradiente de densidade, enquanto que a componente normal, na direção normal à costa, é fortemente influenciada pela forçante de maré. / The aim of this study was simulate the hydrodynamic of the Inner Continental Shelf of the State of São Paulo (PCISP) and of the Mid Continental Shelf of the State of São Paulo (PCMSP) during summer, in response to the density gradient forcing, to the climatological wind shear stress forcing and to the tide forcing, applying the tridimensional hydrodynamic numeric model Regional Ocean Modeling System (ROMS). The experiments performed showed the effects of the density distribution over the general circulation behavior in the PCISP and PCMSP are secondary compared with the induced climatological wind shear stress circulation. The results indicate that in the PCISP and in the PCMSP the component velocity parallel to the coast is dominated by subinertial frequencies forcing, as the climatological wind and the density gradient, while the component velocity perpendicular to the coast is strongly influenced by the tide forcing.

Commonly referred to as “red tide”, harmful algal blooms (HABs) formed by Karenia brevis occur frequently in the Gulf of Mexico (GOM). A bloom is defined as cell abundances >105 cells L-1. This thesis will focus primarily on Karenia brevis, formerly known as Gymnodinium breve, in the Gulf of Mexico. K. brevis is harmful because it produces brevetoxin, a ladder-frame polyether that acts as a potent neurotoxin in vertebrates. K. brevis commonly causes fish kills, respiratory irritation in humans, and Neurotoxic Shellfish Poisoning (NSP) if ingested. Blooms of K. brevis occur almost annually along the West Florida Shelf (WFS) in the late summer and early fall, when the coastal current is favorable for bloom initiation. Along the Texas-Louisiana shelf (TLS) however, blooms of K. brevis are infrequent and sporadic. While much is known of the blooms along the WFS due to their frequent presence, little is known of the mechanisms driving the blooms along the TLS due to their inconsistent presence. To understand the stochastic nature of HABs along the TLS, historical data of bloom occurrences from 1996 to present were compared with NOAA station PTAT2 wind, sea-level pressure, air and water temperature data and NCEP NARR-A sea-level pressure data. The difference in the monthly-mean along-shore component of the wind was statistically significant between bloom and non-bloom years in September (p<<0.001) and April (p=0.0015), with bloom years having a strong downcoast current. Monthly mean water temperature values yielded similar results between bloom and non-bloom years. Both March and September monthly-mean water temperature values were lower during non-bloom years with p-values of 0.01 and 0.048, respectively. These results suggest the possibly of forecasting for HABs along the TLS with currently measured, publicly available data.

Die Bestimmung von Variationen des Meeresspiegels ist heute wichtiger Gegenstand geodätischer Forschungen. So stellt der mittlere Meeresspiegel eine geometrische Grenzfläche der Erdfigur dar. Seine säkulare Änderung ist darüber hinaus eine wichtige Größe u.a. bei der Planung künftiger Küstenschutzmaßnahmen. Die zuverlässige Schätzung dieser Größen aus den relativ kurzen Zeitreihen aktueller Satellitenaltimeterbeobachtungen wird jedoch durch lang- und kurzzeitig wirkende Meeresspiegelvariationen erschwert. Am Beispiel der Ostsee wurde ein Verfahren entwickelt, diese Variationen in den Beobachtungsdaten mit Hilfe modellierter Oberflächenauslenkungen, die einem hochauflösenden ozeanographischen Modell der Ostsee entnommen wurden, zu reduzieren. Die Streuung der beobachteten Höhen wurde so von ursprünglich etwa 15 bis 25cm auf unter 10cm reduziert. Vor der Nutzung des Modells ergab der Vergleich der modellierten mit beobachteten Variationen des Meeresspiegels eine Genauigkeit der modellierten Meeresspiegelauslenkungen von 5 bis 15cm. Darüber hinaus konnte unter Verwendung von Pegelbeobachtungen eine Modellverbesserung erzielt werden. Die Kombination der Beobachtungen unterschiedlicher Altimetermissionen erforderte des Weiteren eine Homogenisierung der Reihen und die Überprüfung ihrer Langzeitstabilität. Hierzu erfolgte eine absolute Altimetervalidierung durch Vergleich mit Pegelmessungen in der südlichen Ostsee. Relative Biaswerte wurden durch Vergleich der Beobachtungen unterschiedlicher Altimeter im Bereich der gesamten Ostsee ermittelt. Die korrigierten und um die modellierten Meeresspiegelvariationen reduzierten Altimetermeeresspiegelhöhen bildeten im Weiteren die Grundlage zur Bestimmung des mittleren Meeresspiegels der Ostsee und seiner säkularen Änderung. Der lineare Trend des Meeresspiegelanstieges in der Ostsee, bezogen auf das Geoid, ergab sich zu (+1,2+-0,8)mm/Jahr. Die Kombination dieses Wertes mit der an Küstenpegeln beobachteten relativen Meeresspiegeländerung erlaubte weiterhin die Schätzung postglazialer Landhebungsraten im Küstenbereich an den Pegelstationen. Die mittlere Meerestopographie innerhalb der offenen Ostsee wurde, bezogen auf ein regionales Geoidmodell, mit einer Genauigkeit von etwa 3 bis 10cm bestimmt. Das erarbeitete Verfahren zeigt das Potential der Kombination geodätischer Beobachtungsverfahren mit den Ergebnissen einer präzisen Modellierung der beobachteten Größe. Die Arbeit stellt eine regionale Studie dar, die - bei Vorhandensein entsprechender Daten - auch auf andere Regionen übertragbar ist. / The determination of sea level variations is a major topic of present geodetic research. The mean sea surface is a geometric boundary surface to describe the figure of the Earth. Its secular change has, for instance, to be considered in future coastal protection projects. However, the estimation of reliable values for these parameters from the relatively short altimeter observation time series is hampered by long- and short-term sea level variations. For the Baltic Sea, a processing scheme was developed that uses sea surface elevations taken from a high-resolution oceanographic model of the Baltic Sea to reduce these sea level variations in the observations. Thus, the standard deviation of the observed sea level heights was reduced from original values of about 15 to 25cm to final values of less than 10cm. A comparison of the modelled and the observed sea level variations was performed before the model was employed. From this, the accuracy of the modelled sea surface elevations was found to be in the order of 5 to 15cm. Moreover, the oceanographic model could be improved by the assimilation of tide gauge observations. The combination of the observations of different satellite altimeters requires also the homogenisation of the time series and the examination of their temporal stability. The comparison with tide gauge observations at the southern coast of the Baltic Sea allowed the determination of the absolute bias of each altimeter mission. Relative bias values were estimated by comparison of altimetric heights of different missions within the entire Baltic Sea. Finally, the time series of the corrected and reduced altimetric sea level heights formed the basis on which the mean sea surface of the Baltic Sea and its secular change were determined. The linear rate of the sea level rise in the Baltic Sea with respect to the geoid was estimated to (+1,2+-0,8)mm/year. This absolute rate was then combined with the relative sea level change observed at coastal tide gauges, allowing the estimation of the rates of the postglacial rebound in the vicinity of the gauges. The mean sea surface topography in the open Baltic was determined with an accuracy of about 3 to 10cm. A regional geoid model served as the reference surface. The presented procedure shows the potential of combining geodetic observations with the results of a precise model of the observed parameter. It can be regarded as a regional study that can be applied also to other regions where observational and modelled data are available.

The research work presents the carried out investigations on the effect of the celestial bodies on the gravity field elements and the analysis was made on the Moon’s and Sun’s effect on the geodetic measurements. The results of the research are advised to be implemented for the assessment of the effect of the celestial bodies regarding the geodetic, measurements as well as when selecting the surfaces of the Earth and geoid and the system of gravity. The dissertation consists of introduction, four chapters and the summation of the results. The introduction depicts the topicality of the chosen research, determining the relevance of the investigated issue. There are described the objective of the work as well as the tasks, there is revealed the scientific novelty of the work ant etc. Chapter one deals with the review of the scientific literature. The chapter also presents the analysis of the available methods of the assessment of the Earth’s tides and their accuracies. The scientific literature was analysed extensively in terms of the effect of the celestial bodies on the Earth’s gravity field and on the issues of the geodetic measurements. The problems were indicated concerning the assessment of the effect of the celestial bodies and the tasks were specified for the research work to be investigated. Chapter 2 deals with the theoretical research. The author presents the analysis of the effect of the members of the series of the tide potential caused by the celestial bodies on... [to full text] / Disertacijoje pateikti dangaus kūnų įtakos sunkio lauko elementams tyrimai ir nagrinėjamas Mėnulio ir Saulės poveikis geodeziniams matavimams. Pagrindinis disertacijos tikslas – ištirti ir įvertinti dangaus kūnų poveikį sunkio lauko elementams ir patobulinti dangaus kūnų poveikio geodeziniams matavimams įvertinimo metodikas. Atlikto darbo rezultatus galima panaudoti vertinant dangaus kūnų poveikį geodeziniams, gravimetriniams ir geodezinės astronomijos matavimams, taip pat pasirenkant Žemės ir geoido paviršius bei sunkio sistemą, dangaus kūnų poveikio įvertinimo atžvilgiu. Disertaciją sudaro įvadas, keturi skyriai ir rezultatų apibendrinimas. Įvadiniame skyriuje pagrindžiama tiriamoji problema, apibrėžiamas problemos aktualumas, formuluojamas darbo tikslas bei uždaviniai, aprašomas mokslinis darbo naujumas, pateikiami ginamieji disertacijos teiginiai pristatomos autoriaus publikacijos ir pranešimai konferencijose, aprašoma disertacijos struktūra. Pirmasis skyrius skirtas literatūros analizei. Jame nagrinėjami esami Žemės potvynių įvertinimo metodai ir jų tikslumas. Išanalizuota mokslinė literatūra dangaus kūnų poveikio Žemės sunkio laukui ir geodeziniams matavimams klausimais. Identifikuotos problemos dangaus kūnų poveikio vertinime ir suformuluoti uždaviniai, kuriuos disertaciniame darbe tikslinga išspręsti. Antrajame disertacijos skyriuje pateiktas teorinis tyrimas. Nagrinėjamas dangaus kūno lemiamo potvynio potencialo eilutės narių poveikis sunkio lauko elementams:... [toliau žr. visą tekstą]

ABSTRACT The Eocene Roda Formation in northern Spain documents the deposits from a range of coastal depositional environments. These include alluvial plains, distributary channels, mouth bars, upper to lower-shorefaces, and tidal shelf ridges. Eighteen progradational sand tongues that are interpreted as parasequences compose two third-order sequences. Sequence 1 accumulated in an environment with strong tidal currents and high rates of progradation, while Sequence 2 was deposited under relatively weaker currents and higher rates of aggradation, which produced a higher mudstone:sandstone ratio. The stratigraphy highlights the transgressive origin of six tidal shelf ridges, three in each sequence, that overlie regressive deltaic tongues. Sequence 1 shelf ridges are composed almost entirely of cross-bedded sandstones, whereas Sequence 2 ridges are composed of a mixture of cross-bedded and ripple-laminated deposits. Ridges in both sequences contain bioturbation that is typical of the Cruziana Ichnofacies, and that indicates a marine origin. The tidal ridges are stratigraphically located at or near the point of maximum third-order regression, and are not found within early highstand or late transgressive deposits― times of high relative sea level when the deltaic shoreline did not protrude significantly. Tidal currents were accentuated at the coast when the delta complex had prograded several kilometres into the basin, while during times of high relative sea level, the basin was wider and tidal currents were weaker, consequently leading to a lack of tidal deposits. The tidal ridges are, thus, interpreted as being headland-associated deposits. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2011-04-29 17:10:10.008

In this study, The Beach Dewatering System, a relatively recent technology to combat beach erosion, which is proposed as a practical alternative to more traditional shoreline stabilization methods, is investigated and an informative overview on the genesis, development and recent use of this technique is provided. On the basis of the link existing between the elevation of beach groundwater and erosional or accretionary trends at the beach face, a numerical model that simulates groundwater flow in a coastal aquifer under beach drainage is presented. In this model, the seaward boundary of the domain is considered to be tidally fluctuating in a large scale to represent the occurrence of seepage face significantly. The unsteady groundwater flow equation is solved numerically using the method of finite differences. The results clearly showed that the water table being lowered caused the reduction of the seepage face which is the main aim of Beach Dewatering projects. The positional design parameters, i.e. horizontal and vertical location of the drain, are also investigated by utilizing an efficiency index. It is observed that the system efficiency decreased as the drain is shifted landward. The results also indicated that, the efficiency slightly increased with the vertical drain elevation.

This study verified if the behavior since formation to dissipation on a Mesoscale Convective Complex (MCC) is somehow related to the sea level rising caused by ocean tide. The objective of this study is to find a possible link between ocean height variation and the MCC event. The ocean tide data were obtained from the Banco Nacional de Dados Oceanográficos (BNDO) between January 2005 and December 2009. The MCC event data in this period were collected in previous researches in UFAL Sinoptics Laboratory which add up the total of 41 cases. When relating the ocean tide forecast data with the MCC, a significant relationship was observed. A significant variation in sea surface temperature related with MCC was detected. There was an evident relationship between seasonality with tide behavior and lunar phase and duration of MCC. The major occurrence of the MCC are in Autumn with 63% of the cases. There are no records of a Winter MCC. The MCC events reached its maximum growth in 63% of cases in the flood tide. The dissipation occurred in 56% of the tidal flow. A probable association between the sea temperature variation with depth of 60 meters with the occurrence of MCC event was verified. A more detailed study of the temperature variations is needed to confirm the relationship. / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Este estudo verificou se o comportamento desde formação à dissipação dos Complexos Convectivos de Mesoescala (CCM) está de alguma forma relacionado a elevação do nível do mar causada pela maré oceânica. O objetivo deste estudo é encontrar uma possível relação entre a variação da altura do oceano e o evento CCM. Foram utilizados os dados de previsão de maré oceânica, obtidos no Banco Nacional de Dados Oceanográficos (BNDO) entre Janeiro de 2005 e Dezembro de 2009. Os dados de eventos CCM no período de estudo, foram adquiridos em trabalhos anteriores do Laboratório de Sinótica da UFAL e somam o total de 41 casos. Ao cruzar os dados da previsão de maré oceânica com os de CCM, observou-se relações relevantes para o estudo. Foram observadas algumas situações de variação significativa na temperatura da superfície do mar com o evento CCM. Ficaram evidentes as relações de sazonalidade com comportamento da maré e fase lunar e duração do CCM. A maior ocorrência dos casos 63% é no Outono. Não existem ocorrências no Inverno. Os eventos de CCM atingiram seu máximo desenvolvimento em 63% dos casos na enchente da maré. A dissipação ocorreu em 56% na vazão da maré. Foi verificada uma possível relação entre a variação de temperatura do mar na profundidade de 60 metros com a ocorrência do evento CCM. Um estudo mais detalhado sobre as variações de temperatura se faz necessário para confirmar a relação.

Made available in DSpace on 2016-12-23T13:47:35Z (GMT). No. of bitstreams: 1 Rafael Almeida Magris.pdf: 1237040 bytes, checksum: 07bea7179db169152f53f5f9f64662ff (MD5) 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.

Made available in DSpace on 2016-06-02T19:28:58Z (GMT). No. of bitstreams: 1 TeseAS.pdf: 2981431 bytes, checksum: 5aa43d392871f5fb8a0ab8af1836259a (MD5) Previous issue date: 2006-06-02 / Universidade Federal de Sao Carlos / Studies related to the quality of the water in coastal environments as bays, estuaries and tidal creeks are important due to the high productivity and intense influence of anthropic activities in these areas. This study aims the physical, chemical and microbiological characterization of diverse tidal creeks along Paraná coast. We analized seasonal variations in four tidal creeks and differences among rainy and dry periods in two tidal creeks. The cellular density of the pico, nano and microplanktonic fractions in different trophic conditions, differentiating the auto and heterotrofic compartments were performed. The temperature, salinity, pH, alkalinity, CO2, dissolved oxygen, nitrite, nitrate, ammonium, phosphate, silicate, suspended matter, particulate organic and humic matter, total chlorophyll, total coliforms and Escherichia coli were analyzed. The pico- and the nanoplankton were analyzed by direct counting under epifluorescence microscopy, while the microphytoplankton and the protozooplankton were through the Utermöhl method. In relation to the physico-chemical and biological characteristics the Perequê tidal creek exhibited larger saline intrusion, and in the Olho d´Água tidal creek was detected great amount of discharged domestic effluents. Among the pico- and nanoplanktonic fractions prevailed the heterotrophic compartment, in both phases. On the other hand, the abundance of the phytoplankton prevailed under the protozooplankton in the microplanktonic fraction along the whole study. Differences between dry and rainy periods were confirmed. In the rainy period was observed in the two tidal creeks an increase in nitrite, suspended matter, organic particulate matter and picoplankton and a reduction of nitrate, chlorophyll, nanoplankton (auto- and heterotrophic) and of the autotrophic microplankton. Increase of phosphate, ammonium and humic substances were only observed in Barranco tidal creek and of dissolved oxygen and E. coli in Olho d´Água. These results show that in periods of high pluviosity elevated amounts of nutrients are exported by the tidal creeks to the adjacent internal continental shelf. It was not possible to define a pattern for none of the variables in relation to the tide and to the day and night periods. / xi Estudos relacionados com a qualidade da água em ambientes costeiros como baías, estuários e gamboas são importantes por serem regiões de alta produtividade e influenciadas por atividades antrópicas. Neste estudo foram avaliadas variáveis físicoquímicas e biológicas em diversas gamboas ao longo da costa do Estado do Paraná. Foram analisadas variações sazonais em quatro gamboas e diferenças entre períodos secos e de alta pluviosidade em duas das gamboas. A densidade celular das frações pico, nano e microplanctônicas, em diferentes condições tróficas e diferenciando os compartimentos auto e heterotróficos, foi avaliada. Foi realizada a análise de temperatura, salinidade, pH, alcalinidade, dióxido de carbono, oxigênio dissolvido, nitrito, nitrato, amônio, fosfato, silicato, material particulado em suspensão, matéria orgânica particulada, substâncias húmicas, clorofila total, coliformes totais e de Escherichia coli. O pico e o nanoplâncton foram analisados por contagem direta em epifluorescência, enquanto que o microfitoplâncton e o protozooplâncton foram determinados pelo método de Utermöhl. Em relação às características fisico-químicas e biológicas, foi detectada uma maior intrusão salina na Gamboa Perequê e a Gamboa Olho d´Água se diferenciou por causa da grande quantidade de efluentes domésticos que recebe. Entre as frações pico e nanoplanctônicas predominou o compartimento heterotrófico, em ambas as fases. Prevaleceu à abundância do fitoplâncton sob o protozooplâncton na fração microplânctonica ao longo de todo o estudo. No estudo sazonal confirmaram-se as diferenças entre os períodos seco e chuvoso. No período chuvoso foi observado aumento de nitrito, material particulado em suspensão, matéria orgânica particulada e picoplâncton e redução de nitrato, clorofila, nanoplâncton (auto e heterotrófico) e do microplâncton autotrófico nas duas gamboas. Foram observados aumento de fosfato, amônio e substâncias húmicas na Gamboa Barranco e de oxigênio dissolvido e E. coli na Gamboa Olho d´Água. Estes resultados mostram que em períodos de alta pluviosidade são exportadas pelas gamboas quantidades mais elevadas de nutrientes para a plataforma continental interna adjacente. Em relação à maré e aos períodos diurno e noturno, não foi possível definir um padrão para as diferentes variáveis analisadas. Palavas-chave: gamboa, picoplâncton, nanoplâncton, fitoplâncton, protozooplâncton, maré, estado trófico.

Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-05-22T17:05:47Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_Lacerda2014 (versão BC).pdf: 15671958 bytes, checksum: bd96e677f6b27688458828455de7708d (MD5) / Made available in DSpace on 2017-05-22T17:05:47Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_Lacerda2014 (versão BC).pdf: 15671958 bytes, checksum: bd96e677f6b27688458828455de7708d (MD5) Previous issue date: 2014 / As zonas costeiras são consideradas áreas de transição entre os domínios continental e marinho, apresentando alta complexidade e dinamismo. Representando aproximadamente 10% das áreas emersas habitáveis, abrigam atualmente cerca de dois terços da população mundial proporcionando inúmeros serviços econômico-sociais a sociedade humana, que em constante expansão sobrecarrega cada vez mais esses ambientes que exercem papéis ecológicos fundamentais na manutenção da biodiversidade (e produtividade) local e de ecossistemas adjacentes (terrestre e marinho). Dentre os diferentes ecossistemas costeiros, os sistemas estuarinos são bastante conhecidos por estarem presentes em praticamente toda a costa brasileira, assim como por apresentarem grande importância ecológica, econômica e social. Na costa nordeste do Brasil muitos ecossistemas estuarinos ainda encontram-se pouco ou até mesmo não estudados, deixando uma lacuna nos estudos ecológicos referentes a esses ecossistemas que além de grande dinamismo também apresentam muitas particularidades, principalmente ao longo dessa região (NE) onde a plataforma continental é mais estreita. Dessa forma, durante o período de doze meses o habitat praia estabelecido na porção externa do estuário do Rio Goiana foi amplamente estudado, tendo como objetivo principal, avaliar o potencial desse ambiente como berçário para as assembleias de peixes. Um total de três desenhos amostrais foram elaborados e executados nas praias adjacentes a foz do Rio Goiana. A partir do esforço amostral, aspectos relacionados à composição e dinâmica da comunidade de fauna, assim como, características morfodinâmicas e ambientais, foram descritos pela primeira vez nesse habitat, que atualmente encontra-se sob a condição de Reserva Extrativista (RESEX Acaú-Goiana). Foi identificado que as praias adjacentes ao estuário ocorrem junto a um extenso terraço de baixa-mar, cortado pelo canal principal do rio ao longo da margem sul do estuário. Por se tratar de um ambiente dominado pela maré, diferentes ciclos ambientais como o ciclo lunar e circadiano, apresentaram grande influencia nos padrões das variáveis ambientais (salinidade, temperatura da agua, oxigênio dissolvido e profundidade), assim como, no uso do habitat pelas diferentes espécies da fauna. A diferença no regime de chuvas ao longo do ciclo sazonal mostrou-se determinante na composição da comunidade biótica das praias, dominadas por espécies estuarinas durante a estação chuvosa, e abrigando um maior número de espécies costeiras durante a estação seca. Esse ciclo sazonal do habitat, estimulado pelas oscilações de variáveis ambientais como salinidade e temperatura, permite que o habitat contemple um maior número de espécies, e aumenta a eficiência do fluxo de energia entre a porção interna do estuário e habitats costeiros adjacentes. A porção externa do estuário do Rio Goiana proporciona um extenso habitat de aguas rasas, ideal para o desenvolvimento inicial de varias espécies de peixes e crustáceos. É nesse habitat, que o berçário de espécies chave para a subsistência de famílias tradicionais como, Mugil spp. e Callinectes danae ocorre. O grande acúmulo de matéria orgânica, típico de terraços de maré, associado às baixas profundidades e transparência, promovem proteção e recursos alimentares para inúmeras espécies em desenvolvimento inicial, se apresentando assim, como uma importante alternativa de berçário para as assembleias de peixes e crustáceos. As praias estudadas podem exercer um importante papel na manutenção da biodiversidade do ecossistema estuarino e adjacente. As informações levantadas no presente estudo são inéditas, podendo servir de auxilio aos órgãos competentes, em seus planos de manejo de ecossistemas costeiros em unidades de conservação. / Coastal areas are considered transition zones between continental and marine environments, with high complexity and dynamism. Representing approximately 10% of the habitable emerged areas, currently home to about two-thirds of the world population providing numerous services (economic and social) to human society, which in constantly expanding, overwhelms these environments which performing key ecological roles in the maintenance of local biodiversity (and productivity ) and in the adjacent ecosystems (terrestrial and marine). Among the different coastal ecosystems, estuarine systems are well known to be present in practically the entire Brazilian coast, as well as presenting ecological, economic and social services. On the northeast coast of Brazil many estuarine ecosystems are still little or even not studied, leaving a gap in ecological estuarine studies, especially over this region (NE), where the continental shelf is narrower providing many particularities to this ecosystems. So, during the twelve-month period, the beach habitat established in the outer portion of the estuary Goiana was widely studied, with the main purpose of evaluating the potential of this environment as a nursery for fish assemblages. A total of three sampling designs were developed and implemented in the sandy beaches adjacent to Goiana River’s mouth. Aspects related to the composition and dynamics of the faunal community, as well as, morphodynamic and environmental features, were described for the first time in this area, a Marine Conservation Unit, of type Extractive Reserve (RESEX Acaú-Goiás). It was identified that the adjacent estuarine beaches occur along an extensive low tide terrace, crossed by the Goiana main channel along the southern shore. As a tide dominated environment, different environmental cycles, such as circadian and lunar cycle, had great influence on the patterns of environmental variables (salinity, water temperature, dissolved oxygen and depth), as well as in habitat use by different fauna species. The differences in rainfall regime along the seasonal cycle, proved decisive in the composition of the biotic community, dominated by estuarine species during the rainy season, and harboring a greater number of coastal species during the dry season. This seasonal cycle of the habitat, allows the sandy beaches to contemplate a larger number of species, and increases the efficiency of energy flow between the inner portion of the estuary and adjacent coastal habitats. The outer portion of Goiana River estuary provides an extensive shallow water habitat, ideal for the initial development of various species of fish and crustaceans. In this habitat, the nursery of key species for the livelihoods of traditional families as Mugil spp. and Callinectes danae occurs. The large accumulation of organic matter (wrack), typical of tidal terraces, associated to lowest depths and water transparency, promote protection and food resources for many species in early development, presenting as an important alternative nursery and feeding site for fish and crustaceans species. Thus, the sandy beach habitat plays an important role in the livelihood of the local community, as well as in maintaining the biodiversity of estuarine-coastal continuum. The information gathered in this study, should be taken into account by environmental agencies in their planning of coastal ecosystems.