Mestrado em Oceanografia Ambiental

URI Permanente para esta coleção

http://repositorio.ufes.br/handle/10/17532

Nível: Mestrado Acadêmico
Ano de início: 2007
Conceito atual na CAPES: 4
Ato normativo: Homologado pelo CNE(Portaria MEC Nº 609 de 14/03/2019) Publicação no DOU em 18/03/2019 Seç. 1, Pág. 63. Parecer CNE/CES nº 487/2018, Processo no 23001.000335/2018-51).
Periodicidade de seleção: Anual
Área(s) de concentração: Sistemas Costeiros e Marinhos
Url do curso: https://oceanografia.ufes.br/pt-br/pos-graduacao/PPGOA/detalhes-do-curso?id=1468

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A bifurcação da corrente do Brasil no embaiamento de Tubarão e seu papel na formação de vórtices ciclônicos
(Universidade Federal do Espírito Santo, 2014-10-13) Servino, Ricardo Nogueira; Azevedo, José Luiz Lima de; Ghisolfi, Renato David; Rigo, Daniel; Paiva, Afonso de Moraes
The transition region from the east to the southeast Brazilian coast, between 19°S and 21°S, shows remarkable geomorphological features that characterizes a complex shelf-break line. The Abrolhos Banks and the Vitória-Trindade Ridge’s (VTR) seamounts are irregularities that promote influences on the system of western boundary currents in this region, specially to the Brazil Current (BC), inducing its meandering and the developing of eddies locally. Confined by these structures around it, the Tubarão Bight (TB) is a region in front of Vitória (20.3°S; 40.3°W) that shelters cyclonic eddies which formation was investigated in this work as influenced by a bifurcation of the BC in this site. The bifurcation of a geostrophic current is a geophysical process of interaction between a jet and a continental boundary that results in the formation of two secondary jets – one in each direction – and that can be responsible for the developing of eddies inside partially confined oceanic basins (e.g Alboran Sea and Sea of Japan). The occurrence of this process was found inside the TB following the impinging of the BC on its continental slope, identified based on numerical modelling results derived from a high-resolution and refined topography simulation. To the extent of our knowledge, this is the first description of such process in this region. This work’s findings suggest that the secondary jet deflected to the TB’s interior is necessary to the developing and maintenance of two kinds of eddies with different size, duration and date of occurrence. These eddies’ characteristics and the bifurcation’s itself were significantly linked to the flowing pattern of the BC through the VTR’s seamounts.
A correlação da cadeia produtiva da pesca com as comunidades pesqueiras da região costeira do Espírito Santo
(Universidade Federal do Espírito Santo, 2018-08-30) Paz, Micael Lincoln Cardoso; Fernandes, Luiz Fernando Loureiro; Zappes, Camilah Antunes; Dadalto, Maria Cristina
A corrente do Brasil no Embaiamento de Tubarão : Oceano Atlântico sudoeste
(Universidade Federal do Espírito Santo, 2014-10-17) Martins, Tayná Rosa; Silva, Meyre Pereira da; Ghisolfi, Renato David; Dias Júnior, Camilo
A dinâmica da camada de mistura oceânica da porção Abrolhos-Campos da costa brasileira
(Universidade Federal do Espírito Santo, 2015-12-21) Salviato, Júlia Tavares; Ghisolfi, Renato David; Bastos, Alex Cardoso; Mill, Guilherme Nogueira
The oceanic surface mixed layer is the link by which the ocean and atmosphere are coupled. The characteristics of the mixed layer determine the air-sea fluxes of heat and gases affecting this way the climate. Additionally, biogeochemical cycles and biological productivity are profoundly affected by the mixed layer depth, which controls the amount of nutrient input to the euphotic zone through vertical mixing and entrainment. Improved understanding of these processes depends in some measure on our understanding of mechanisms and dynamics of the mixed layer. Using temperature and salinity from WOA, heat fluxes from OAFlux Project (Objectively Analyzed air-sea Fluxes) and wind stresses from Comprehensive Ocean-Atmosphere Data Set (COADS) the spatial pattern of the seasonal variability of mixed layer in the Abrolhos-Campos region is investigated, as well as the importance relative of heat and momentum fluxes and Ekman pumping to the seasonal heat-budget of the mixed layer. To complement the above analysis and to investigate mixed layer dynamics at suprainertial scale, time series from October 2011 to October 2012of air-sea fluxes and upper ocean response, obtained from PIRATA mooring at 19oS and 34oW were also analyzed. The seasonal cooling and deepening of the mixed layer is driven primarily by heat fluxes with larger contribution from the short wave radiation. By the end of the winter and spring, strong wind stresses are important to maintain the mixed deep. Ekman pumping velocities play only a small role in the upper ocean evolution in the region of study. In general, the results of the analysis of PIRATA time series confirm those from the climatological data sets. Furthermore, spectral analysis of the mixed layer computed from the PIRATA time series revealed a sharp energy peak at about 12 and 24 hours, suggesting the contribution of internal tides to oceanic mixing.
Análise da estruturação da paisagem costeira do Espírito Santo
(Universidade Federal do Espírito Santo, 2014-11-28) Cancian, Tobias Betzel; Barroso, Gilberto Fonseca; Quaresma, Valéria da Silva
Análise da resposta acústica em sedimentos marinhos
(Universidade Federal do Espírito Santo, 2014-04-13) Menandro, Pedro Smith; Quaresma, Valéria da Silva; Bastos, Alex Cardoso; Ghisolfi, Renato David; Ayres Neto, Arthur
Submarine geoacoustics helps in understanding the behavior of propagation and attenuation of sound in sediment, providing an information set which assists the major data interpretation approaches. The detection of muddy deposit through high resolution acoustic records is generally easy, usually appearing as free reflection layers. However, this acoustic response depends on the frequency used and other characteristics of the deposit, even of the water column. The dynamics of these muddy layers may have influence in many areas, from engineering and harbor maintenance, to biology and studies of impact on benthic biota. The development of a rapid and efficient mapping method for these deposits seems to be a demand for knowledge advance of the processes involved in the transport, deposition and suspension. Thus, this study has two main approaches divided into two independent studies: i) investigate how the acoustic signal response from different sources changes with the frequency and sediment physical properties (grain size and density), and ii) associate variations observed in the acoustic records with sediment mobility over a tidal cycle. The dataset consists of high-frequency geophysical records ( 3.5, 33 and 210 kHz ) , sediment physical properties, in situ density , hydrodynamics and distribution of suspended particulate matter, which were collected at the North Channel of Amazon River . The first chapter showed that different survey methods at the same area can provide different results. Furthermore, the frequency and density were important properties to understand the relationship between surface sediment and acoustic features. The second chapter was an attempt to evaluate sediment dynamics through acoustic system, and showed that the changes in the processes of sediment transport were recognized by the ADCP and OBS allowing to distinguish the acoustic echo sounder records and to interpret sedimentary dynamic processes.
Aspectos etnobiológicos e etnoecológicos na pesca artesanal em três municípios do litoral sul do Espírito Santo
(Universidade Federal do Espírito Santo, 2018-03-16) Oliveira, Ana Carolina Machado de; Zappes, Camilah Antunes; Braga, Adriane Araújo; Martins, Agnaldo Silva; Preto, Bruno de Lima
This study aims to relate the traditional knowledge of fishermen to the scientific literature, as regards ethnobiological and ethnoecological aspects of decapod crustaceans caught in artisanal fishing on the Southern coast of Espírito Santo. The research was done in Anchieta, Piúma and Marataízes cities, South coast of Espírito Santo, and data collection occurred between September 2016 and February 2017. The ethnografic method used consisted of: 1) participant observation method; 2) semi-structured interviews and questionnaires; 3) snowball method; 4) method of triangulation of results. A total of 92 artisanal fishermen were interviewed, all aged between 18 and 71 years. In Anchieta city the target species of the fishing are the sea-bob shrimp, pink shrimp and white shrimp, and in Piúma and Marataízes only the sea-bob shrimp. The carcinofauna, captured in the three municipalities, is composed mainly of crabs and swimming crabs. The fishermen demonstrated knowledge about the biology of the species of crustaceans captured, differentiating the juvenile stages of the adults, as well as an occurrence of sexual dimorphism, once they recognize the copulatory organ of male shrimps (petasma) and in the females the presence of a greenish color in the dorsal region characterized by ovary development. In crabs and swimming crabs, the respondents reported that the shape of the abdomen is different between the sexes. The habitat of decapod species has also been described. Fishermen considered crustaceans to be important for the environment because: 1) they play roles in the dynamics of the marine community, in the food chain and in the processes of organic matter cycling and energy flow; 2) are important for consumption; and 3) are used for bait and comercialization. When questioned about the fisheries closure season, fishermen consider important but incorrect for the region, which indicates the need of greater dialogue between enforcement agencies and fishing communities. The information of this research corroborates with the literatura and can function as a tool for the management of fishery resources, and on the decrease of the impact on the populations of the target species and fauna by-catch, aiming at the sustainability of fishing and the valuing of coastal communities of Southern Southern coast of Espírito Santo.
Aspectos fisiográficos, sedimentológicos e estruturais do fundo marinho em uma área da porção central da bacia do Espírito Santo
(Universidade Federal do Espírito Santo, 2012-12-17) Tschiedel, Flávio Eduardo; Bastos, Alex Cardoso; Silva, Cleverson Guizan; Quaresma, Valéria da Silva
The development of industrial activity in the state of Espírito Santo (Brazil) in recent years has been highlighted in offshore regions. The government agency that controls the activities of oil exploration and production in sedimentary basins in Brazil requires, for activities offshore, the geological knowledge of the seabed as well as geological structures related to it that may cause geological and environmental risk in the future. Engineering works in these areas are related to the development of the activity of exploration and production of oil primarily. The lack of knowledge of buried geological features and geological aspects of the seabed may hinder or impede the execution of projects in this activity due to unforeseen peculiarities. This work includes the identification of physiographic features of the seabed in the Continental Shelf and Slope areas in the Espírito Santo sedimentary basin. The area is about 45km away from the coast, adjacent the Doce River mouth. In order to reach the target, this study uses various analysis tools (2D and 3D seismic, high resolution seismic, seabed samples and wells) aiming at identifying seabed characteristics, involving structural and sedimentological aspects. It also presents a brief discussion about the applicability of the use of geophysical methods in this study, and a comparison of the uses of geophysical methods and their ability to identify the physiographic features of the seabed in the area of this project. At the end a predictive map of physiographic characteristics of the seabed is presented, identifying areas of salt influence and geological faults, channels and others. The area was subdivided into three regions, taking into account the predominance of physiographic features and geological risks they present.
Avaliação do estado trófico de um sistema estuarino tropical a partir do índice trófico TRIX
(Universidade Federal do Espírito Santo, 2014-06-27) Bertoldi, Larissa; Barosso, Gilberto Fonseca; Quaresma, Valéria da Silva; Dias Junior, Camilo; Chícharo, Luis Manuel Zambujal
The estuarine ecosystem is located in the interface continent - ocean, with hydrodynamic, morphological, biological and sedimentary characteristics influenced by freshwater discharge from the drainage basin, and oceanographic processes. The Piraquê–açu and Piraquê–Mirim’s Estuarine System (SEPAPM) (7,48 km2), located in the district of Santa Cruz (Aracruz, ES), is predominantly situated in the valleys of Formação Barreiras. The SEPAPM has great importance, providing many goods and services to the local economy, as well as having a predominantly natural setting with no history of significant dredging and engineering works. Thus, is necessary to investigate it characteristics understanding the ecological processes to contribute to coastal zone management. Therefore, this study aimed to assess the trophic conditions of SEPAPM through environmental variables chlorophyll a, total phosphorus (TP), dissolved inorganic nitrogen (DIN), percentage of oxygen combined into a Trophic State Index (TRIX). Influence of river discharge were considered on TRIX. Samples were taken at 10 sampling stations in the rainy and dry periods of 2012. Point data variables were interpolated in Geographic Information System - GIS using the Spline method. As a result, the trophic condition of SEPAPM show eutrophic trends (TRIX > 6). The SEPAPM showed significant spatial variation of chlorophyll a and salinity in the rainy season and percentage of oxygen and salinity in the dry season; Significant temporal variation of TP, dissolved inorganic nitrogen, oxygen percentage and salinity. There was a negative significant correlation using the Spearman test between chlorophyll a and salinity (dry and rainy), chlorophyll a and flow (dry), TP and salinity (dry), NID and percent oxygen (dry), TRIX and percent oxygen (dry), salinity and flow (dry and rainy) chlorophyll a and oxygen percentage (rainy), TF and NID (rainy) and TRIX and TP (rainy). There was a significant positive correlation for percentage of oxygen and chlorophyll a (dry), TRIX and NID (dry and rainy), oxygen percentage and flow (rainy), salinity and TRIX (rainy) and TP and flow (rainy). This work appears as a management tool for the steering committee of the North Coast Regional Hydrographic Center.
Avaliação do ITS1 e do ITS2 como barcode para Calanoida (Crustacea, Copepoda) marinhos e como marcador complementar para filogenia do grupo
(Universidade Federal do Espírito Santo, 2014-06-06) Rocha, Gustavo Martins; Fernandes, Luiz Fernando Loureiro; Farro, Ana Paula Cazerta; Milstein, Daniela
Calanoida is the most abundant copepod Order in the world, having recognized ecological and scientific importance. But the accurate morphological taxonomic identification of this animal group is not simple, requiring years of experience and practice, especially when working with specimens in larval and juvenile stages. Thereat, molecular identification through DNA barcode is an important tool for assistance the identification of these organisms on the species taxonomic level. The mitochondrial marker Cytocromo Oxydase I (COI) is considered standard for molecular identification of most animal groups, but it doesn’t seems as efficient for calanoid copepods. This study aimed to test the two subunits of the nuclear molecular marker Internal Transcribed Spacer (ITS1 and ITS2) as a barcode for this animal group. We tried to sequence ITS1, ITS2 and COI from 105 individuals representing 14 families of Calanoida. Sequencing success rates of nuclear markers were much higher than those from COI (98%, 91% and 34%, respectively). In addition, it was found a gap between intraspecific and interspecific genetic distances for the nuclear molecular markers that allow grouping 100% of the sampled individual’s sequences with other individuals’ from the same species in monophyletic clades for ITS2 and with one exception for ITS1. Phylogeny of Calanoida, based on ITS1-ITS2-COI concatenated sequences, proved to be congruent with what has already been established in relation to the evolutionary relationships of species in the group. Despite the need for additional studies to confirm the patterns found here, we can conclude, based in our results, that both ITS1 and ITS2 are molecular markers that are easy sequenced and have enough variation to be used for DNA barcoding of marine calanoids.
Caracterização da circulação e balanço do material particulado em suspensão (MPS) na desembocadura da baía de Vitória/ES
(Universidade Federal do Espírito Santo, 2012-03-28) Garonce, Flávia Acypreste Alfredo; Quaresma, Valéria da Silva; Guerra, Josefa Varela; Ghisolfi, Renato David
Understanding estuarine dynamics is an extremely arduous task due to the numerous variables that can influence the system, such as tide, river flow, wind, morphology, among others. However, such studies are necessary due to the large use of this environment for navigation, creation of ports, fisheries, tourism, and a range of goods and services it provides. Thus, this study aimed to contribute to the knowledge of hydrodynamics and flow properties (SPM and salt) in the mouth of the estuary of the Bay of Vitoria. For this purpose measurements were made in four tidal cycles, two in spring tides and two in the neap tides, with seasonal variations between summer (rainy season) and winter (dry season), salinity and temperature with a CTD (OBS 3A) currents with a ADCP (River Surveyor). For the analysis of SPM water samples were collected. This water samples were filtered to obtain the concentrations thereof. From our analysis, this section of the estuary was classified according to the diagram Hansen and Hattray (1966) as the type 1a in springs tide and 2b in neap tide during dry season and 2b in neap tide rainy season. This corroborates the findings using Richardson layer number where the highest values were found during the neap tide rainy, it was the cycle that showed greater stratification. Although there were variations between the dry and rainy season tides was the main forcing controlling hydrodynamic processes in the estuary. Salt and MPS, there were predominantly imported, except for the spring rainy cycle, were exported SPM. In addition, the dynamics of the suspended material showed a nonconservative behavior, with no association with the current processes although lags interfere in the transport, it may be observed due to residual tidal currents (asymmetry tide) is mainly toward the sea. Furthermore, it was realized that the tide was the most active in providing through the suspension of the bottom, and the process of tidal pumping that allowed transport into the estuary.
Caracterização de habitats em áreas de proteção marinha através de imageamento com veículo de operação remota (ROV)
(Universidade Federal do Espírito Santo, 2019-03-21) Silva, Diego Bezerra de Melo e; Fernandes, Luiz Fernando Loureiro; Bastos, Alex Cardoso; Maia, Luís Parente
Studies of characterization of benthic communities and habitats are of paramount importance in the elaboration of management plans and in the preservation of marine biodiversity, especially in areas of marine protection, regions considered of relevant ecological interest. At the Santa Cruz Wildlife Refuge (RVS) and the Environmental Protection Area (APA) in the state of Espirito Santo, there are several potentially anthropogenic activities that cause impacts, such as fishing activity and exploration and production of oil and gas occurring near the region. The objective of this study was to characterize the main habitats in the region of the RVS of Santa Cruz and the APA Costa das Algas, using remotely operated vehicle (ROV) imaging techniques and its correlation with the sedimentological material. The records were obtained through 50 collection stations distributed along the continental shelf, from the 10 m isobath. Five habitats were identified and described as Terrestrial Sands, Carboniferous Gravels, Rodoliths and Gravels, Reefs and Rodolites and Laterites (Hardground), refining the level of knowledge in relation to that already existing in past and more regional studies of the study area. It was possible to identify a greater abundance in the habitat described as Reefs and Rodolites, located in the deeper portion of the APA Costa das Algas, having as opposite the Terrestrial Sands habitat, mostly comprising at the RVS of Santa Cruz. The method used proved to be satisfactory for this type of characterization, which can be replicated in studies of more sensitive areas. The results obtained in the present study will be able to subsidize the managing organ of the two protected areas in the elaboration of their respective management plans.
Caracterização e distribuição dos minerais pesados ao longo da plataforma continental do Espírito Santo
(Universidade Federal do Espírito Santo, 2018-05-29) Costa Junior, Adeildo de Assis; Turbay, Caio Vinícius Gabrig; Quaresma, Valéria da Silva; Bastos, Alex Cardoso; Ferreira Júnior, Paulo Dias
The heavy minerals have a density greater than 2,8 g/cm3 , upper to that of quartz (2,65 g/ cm3 ) and appear as accessory minerals in sedimentary, igneous and metamorphic rocks. The heavy minerals were used as a tool to better understand the past and present sedimentary processes of the Continental Shelf of Espírito Santo (CSES). The study area was subdivided into 3 sectores: Paleovalley Shelf, Doceriver Shelf and Abrolhos Shelf. The sediments found in the CSES are siliciclastic, biodetritic and mixed distributed in a peculiar manner respecting the different sedimentological characteristics governed by accommodation and supply regimes. Fifteen different species of heavy minerals were identified in the CSES: Ilmenite, limonite, sillimanite, zircon, tourmaline, epidote, monazite, hematite, magnetite, grenade, staourolite, rutile, titanite, andaluzita and kyanite. The deposits of heavy minerals with higher concentrations are found in the Doce river Shelf and Abrolhos Shelf, presenting values of maximum content of 3,6%. ZTR index values (zircon, tourmaline and rutile) associated with the interpretation of bathymetric profiles and geological knowledge on CSES have led us to believe that the most expressive heavy mineral deposits are composed of relict sediments possibly from past river transport associated with the relative lowering of sea level in the Late Quaternary.
Composição e estrutura da comunidade zooplanctônica de um estuário tropical (Espírito Santo, Brasil)
(Universidade Federal do Espírito Santo, 2010-03-12) Nunes, Rafaela Aliprandi; Fernandes, Luiz Fernando Loureiro; Dias Junior, Camilo; Bonecker, Sergio Luiz Costa
With the aim to analyze the zooplankton community structure at the Piraquêaçu/ Piraquê-mirim Rivers Estuary, regarding their temporal and spatial variations and tidal, monthly sampling between May 2008 and April 2009 were performed, during the neap and spring tides, in four sampling locations. A total of 64 taxons were identified, with Arthropoda being the most representative with 47 taxons. The most abundant species (88.32% of the total samples) were the copepods Acartia lilljeborgi, Temora turbinata, Parvocalanus crassirostris, Oithona oswaldocruzi, Oithona oculata, Euterpina acutifrons, Paracalanus parvus, Brachyura larvae, Cirripedia (cypris and nauplius) and Gastropoda larvae. Average total abundance presented a defined seasonal and spatial pattern, with higher values during the raining period and at the inner estuary stations, however, no pattern related to tidal fluctuation was observed. Species richness did not show a temporal pattern related to tidal fluctuations, however, a spatial pattern was observed, with higher values closer to the estuary entrance. Diveristy and equitabilty did not present either a temporal or spatial pattern, nor in relation to tides. The Piraquê-açú/Piraquê-mirim river estuary is strongly influenced by the rainfall regime. Variability of the environmental conditions, however, caused alterations in the zooplankton composition, temporal and spatial distributions in this estuary.
Desenvolvimento e morfodinâmica de praias sobre plataformas de abrasão em litorais de micromaré dominados por ondas
(Universidade Federal do Espírito Santo, 2018-03-21) Souza, Brenda Silva de; Albino, Jacqueline; Bastos, Alex Cardoso; Oliveira, Leonardo Azevedo Klumb
Beaches on shore platforms are influenced by their singular geomorphology and respond differently from sandy beaches in terms of morphology and morphodynamic processes. The application of models has become a useful tool in the study of these complex environments. The model of Trenhaile (2004), proposed for mesotidal and macrotidal shore platform coasts, has been considered the most suitable among several models. This model considers the morphology of the shore platforms and hydrodynamic conditions of the coast. Studies about beach development on shore platforms along microtidal coasts, not frequently, consider the contribution of hydrodynamic factors. Thus, the aim of present study was to propose a new model for the development of beaches on shore platforms in microtidal coast, where waves are the fundamental morphodynamical agent. This propose was based on Trenhaile (2004) assumptions and elements. In addition, the influence of the shore platforms on the morphodynamic processes of these beaches was evaluated. The study area comprised three beaches on shore platforms located in the coast of Espírito Santo, Brazil, classified as microtidal coast. Some adaptation from Trenhaile model (2004) were applied for the success of new model: the vertical limit of emerse beach profile was obtained by wave run up during spring tidal and profile morphology data were known by field survey. The results indicated that shore platforms do not prevent the accumulation of sediments and, consequently, the formation of beaches. Although, shore platform exerts significant influence on the limitation of the accommodation space, on beach morphology and morphodynamic processes. In general, the new model was able to represent the morphology and the sediment accommodation capacity of the studied beach systems.
Dieta e ecologia alimentar do boto-cinza, Sotalia guianensis (Cetartiodactyla: Delphinidae) na região do banco dos Abrolhos, Costa Central do Brasil
(Universidade Federal do Espírito Santo, 2014-03-10) Rodrigues, Vitor Leonardo Amaral; Farro, Ana Paula Cazerta; Joyeux, Jean-Christophe; Ott, Paulo Henrique
In the present study the diet and feeding ecology of Guiana dolphin (Sotalia guianensis) from Abrolhos Bank region was investigated by analyzing the stomach contents of 42 stranding individuals, from 2003 to 2012. The food itens were identified at the minor taxonomic level by the prey hard structures (sagittal otoliths and cephalopod beaks) and also quantified by count, size and biomass. The bony fish were the mainly food resource of Guiana dolphin, followed by cephalopods and crustaceans. The overall diet was comprised by 37 prey taxa, being 33 bony fishes, two cephalopods and two crustaceans. The mainly consumed prey taxa were I. parvipinnis, S. rastrifer, Bagre sp., Macrodon sp., T. lepturus, e Mugil sp. The ontogenetic development of Guiana dolphin seems to affect their feeding patterns, so that, prey items consumed by juvenile dolphins were smaller and their diet less diverse compared to adult ones. The diet composition even showed a seasonal pattern as follow: cutlass fish (T. lepturus), squids and the shortfin-corvina (I. parvipinnis) were most abundant in the summer; catfish (Bagre sp.) and mullet (Mugil sp.) were most common in the winter/autumn and the star drum (Stellifer sp.) and king weak fish (Macrodon sp.) were predominant during spring. This study provides evidences of Guiana dolphin being a generalist and opportunistic forager in the studied region as it showed a wide feeding spectrum, low dominance for most preys and great diet variation between the individuals. Regarding the ecological classification, the mainly prey taxa of Guiana dolphin came from benthic demersal habitats, occur over soft bottom and present some estuarine dependency. Also was observed a great contribution of soniferous fishes to diet reinforcing the hypothesis that this small cetacean use audition or even passive electroreception to detect their prey. This study provides the first description of Guiana’s dolphin diet on Abrolhos Bank region and also gives important insights on feeding ecology of this specie as like: ontogeny, seasonality, feeding strategy and individual variation.
Dinâmica de um canal estuarino fracamente estratificado
(Universidade Federal do Espírito Santo, 2014-03-11) Silva, Fernanda Nascimento de Paula e; Quaresma, Valéria da Silva; Bastos, Alex Cardoso; Vinzon, Susana Beatriz
The aim of this study is to describe spatial structures of tidal and subtidal flows in an estuarine channel under different hydrologic and tidal conditions. Estuaries are regions with major economic, environmental and social importance. Therefore, knowing the patterns of circulation in them is essential, especially because they are responsible for controlling biogeochemical environmental standards. Even though estuarine hydrodynamics have been studied under different oceanographic conditions, regions like estuarine system Piraquê-açu Piraquê-mirim (SEPAPM) are still unknown, making important to investigate which are the dominant factors that influence these environment. SEPAPM has well marked hydrological seasonality, weak vertical stratification, semidiurnal tides and a bathymetry with a deep channel followed by a plateau of? approximately 50% of the channel depth and 5 times wider. Therefore, a cross-channel estuarine dynamics were analyzed, seeking to determinate the tidal and subtidal flows as well as the bathymetry, wind and river discharge influence. In the estuary were analyzed: (i) the spatial and temporal structures of temperature, salinity and density, (ii) tidal flow, and ( iii ) both longitudinal (W-E) and transverse (N-S) subtidal flow. We used data collected in 2010 during two distinct seasons (wet and dry) in each tide period (neap and spring). It was determinate that this part of the estuary is weakly stratified, vertically and horizontally, and the tidal straining process is dominant for the stratification process in all sampling periods. The semidiurnal tidal amplitude and phase had a homogeneously pattern at the profile, although in the presence of high amplitude current it may occur horizontal shearing with the greatest amplitudes in the channel. The residual flow showed a clear pattern of gravitational circulation, even under different conditions. Nevertheless, over the sampling periods, the residual flow was dominated by friction in the dry season and the topography in the rainy season. The residual flux founded for spring dry was considered atypical and caused due to weather conditions. Finally, the lateral flow showed greater variation in different seasons, with opposite patterns, a counterclockwise gyre in the dry and a clockwise gyre in the wet. The sediment transport was also inverse in both seasons, occurring import of sediment during the dry season and export during the wet season, probably related to lateral flow.
Dinâmica e o estágio evolutivo do sistema praia-falésia em Maimbá-ES
(Universidade Federal do Espírito Santo, 2018-02-06) Eguchi, Branco Mateus Murata; Albino, Jacqueline; Muehe, Dieter Carl Ernst Heino; Ghisolfi, Renato David
Dinâmica espaço-temporal da macrofauna bentônica em duas praias arenosas da ecorregião marinha leste do Brasil
(Universidade Federal do Espírito Santo, 2015-06-16) Coutinho, Mariane Silva; Bernardino, Angelo Fraga; Joyeux, Jean Christophe; Barros, Francisco Rocha
Sandy beaches are dynamic environmentalunder strong interaction among sand grain size, waves energy and tidal variation. This type of beach hasa great economic and ecologic importance because they dominate the most coastal areas. Associated with beaches sediments, benthic invertebrates assemblages are closely related to hydrodynamic, chemistry and biological forces of these ecosystems, resulting in spatialand temporal distribution patches. These heterogeneity assemblagesoccurin local, regional and also latitudinal spatial scales, exhibit biogeographic patterns well know in benthic abundance, biomass and species richness.Numerous efforts in description of benthic macrofauna spatial-temporal variation on sandy beaches were realized in Brazil, mostly concentrated in Southeastern Marine Ecoregion between Rio de Janeiro, São Paula and Paraná States.This study search understand spatial and temporalscales of variability in benthic macrofauna (i.e.>500µm) through a hierarchical sampling oftwo sandy beaches within Eastern Marine Ecoregion of Brazil in two different times (the winter of 2011 and the summer of 2012). By sampling on beaches with similar morphodynamic, we tested the hypothesisthat spatial variation (i.e., meters to hundreds meters scales) in benthic assemblages structure will be more significant and directly related to abiotic variables compared to seasonal fluctuations of temperature, productivity (measure by availabilityorganic sediment) and morphodynamic beach. As expected, the beaches showed small spatial and temporal differences in abiotic and morphodynamic, but some differences in faunal composition were evident. Hierarchical sampling showeddifferencesin faunal composition and density in local spatial scales (meters to hundreds meters) and temporal scales (winter and summer). The macrofauna abundance and composition respondeddirectly to the contentof organic matter and sand grain size. The beaches of Eastern Marine Ecoregion had some particularpatterns compared to other beacheson Brazilian coast, as the presence of Nemertea and Oligochaeta betweenmacrofauna. In general, we confirm the hypothesisthat spatial variability of macrofauna assemblages of these beaches is greaterthansmall spatial scales duechanges sedimentary parameters
Dinâmica sedimentar no Sistema Estuarino do Piraquê-Açu, Aracruz/ES
(Universidade Federal do Espírito Santo, 2018-07-16) Alves, Rodolfo Teixeira; Quaresma, Valéria da Silva; Jardim, Alex Fabiano; Gallo, Marcos Nicolás

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