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SciELO Brasil - Scientific Electronic Library Online (77,247 recursos)
SciELO (Scientific Electronic Library Online) is an electronic library covering a selected collection of Brazilian scientific journals. The objective of the site is to implement an electronic virtual library, providing full access to a collection of serial titles, a collection of issues from individual serial titles, as well as to the full text of articles. The project envisages the development of a common methodology for the preparation, storage, dissemination and evaluation of scientific literature in electronic format.

Brazilian Journal of Oceanography

Mostrando recursos 1 - 20 de 71

1. THE STRUCTURE OF SUBTIDAL MACROALGAL ASSEMBLAGES AT THE TAMOIOS ECOLOGICAL STATION, A THREATENED CONSERVATION UNIT IN RIO DE JANEIRO, BRAZIL - Koutsoukos,Victor de Souza; Villaça,Roberto Campos; Széchy,Maria Teresa Menezes de
The structure of subtidal rocky bottom communities at Tamoios Ecological Station (TES), situated in Ilha Grande Bay, Rio de Janeiro State, as well as in other Brazilian marine protected areas, is insufficiently characterized. The present study describes the macroalgal assemblages of shallow subtidal rocky bottoms on two islands of the TES-Imboassica (IM) and Búzios Pequena (BP)adopting species and genera as observational units. Two sites were surveyed on each island in summer 2011. Random 30x30 cm quadrats (n=3) were scraped to collect all macroalgae except crustose species. The subtidal assemblages, in which 58 macroalgal species occurred, were characterized by the high...

2. GENOTOXICITY OF SHALLOW WATERS NEAR THE BRAZILIAN ANTARCTIC STATION "COMANDANTE FERRAZ" (EACF), ADMIRALTY BAY, KING GEORGE ISLAND, ANTARCTICA - Rocha,Arthur José da Silva; Botelho,Marina Tenório; Hasue,Fabio Matsu; Passos,Maria José de Arruda Campos Rocha; Vignardi,Caroline Patricio; Ngan,Phan Van; Gomes,Vicente
Series of biomonitoring surveys were undertaken weekly in February 2012 to investigate the genotoxicity of the shallow waters around the Brazilian Antarctic Station "Comandante Ferraz" (EACF). The comet assay was applied to assess the damage to the DNA of hemocytes of the crustacean amphipods Gondogeneia antarctica collected from shallow waters near the Fuel Tanks (FT) and Sewage Treatment Outflow (STO) of the research station, and compare it to the DNA damage of animals from Punta Plaza (PPL) and Yellow Point (YP), natural sites far from the EACF defined as experimental controls. The damage to the DNA of hemocytes of G....

3. COMMUNITY STRUCTURE OF THE TINTINNIDS (CILIOPHORA: SPIROTRICHEA) IN THE REGION OF ABROLHOS (BAHIA, BRAZIL) - Costa,Alejandro Esteweson Santos Faustino da; Neumann-Leitão,Sigrid; Thompson,Fabiano Lopes; Melo,Pedro Augusto Mendes de Castro; Santana,Jana Ribeiro de
The tintinnid community in the region of Abrolhos (Bahia, Brazil) was studied during February 2012. We hypothesized that the tintinnid community structure varies significantly over a short temporal scale (photoperiod), as well as spatially over a short scale (on and away from the reefs), and a broad scale (distance of the reef area from the coast). Three areas in Abrolhos were studied. Two sampling points were delimited in each area, where the tintinnids were collected by horizontal subsurface plankton net (20 μm mesh-size) hauls. Sampling was undertaken every 6 hours, during 24 hours in each area. 24 species were found,...

4. POLYCHLORINATED DIBENZO-P-DIOXINS, DIBENZOFURANS, AND BIPHENYLS IN FREGATA MAGNIFICENS FROM ILHA GRANDE BAY, RIO DE JANEIRO STATE, SOUTH-EASTERN BRAZIL - Ferreira,Aldo Pacheco
The purpose of this paper is to perform analyses in a fish-eating seabird species which is recognized to be at risk of accumulating toxic contaminants due to its high position in the trophic web and to its low ability to metabolize xenobiotic compounds. Fregata magnificens were collected at Ilha Grande Bay, Rio de Janeiro, Brazil (23°8'26"S, 44°14'50"W) between February, 2009 and April, 2013. Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs), were analyzed in tissue composites, being subsequently identified and quantified using gas chromatography coupled with mass spectrometry. The concentrations were below the range of concern established by World...

5. COMPETITION FOR SPACE BETWEEN FISHING AND EXPLORATORY OIL DRILLING, OBSERVED FROM A DRILLING PLATFORM IN THE ESPIRITO SANTO BASIN, SOUTHEASTERN BRAZIL - Silva,Alessandra Coutinho Thomé da; Valentin,Jean Louis; Vianna,Marcelo
Fishing and oil drilling compete for space in some regions off the Brazilian coast. Fish congregate around drilling platforms, which attracts fishing vessels that may illegally breach the 500 m safety perimeter. The objective of this study was to identify the fleets that frequent the safety zone of a platform and their behavior and to determine if there was a seasonal relationship in this interaction, during two exploration campaigns, in different periods, carried out on the "Ocean Star" platform in the Espírito Santo Basin. The results indicated a high incidence of artisanal fishing vessels inside the prohibited area, and of...

6. SEASONAL AND SPATIAL PATTERNS OF TOXIGENIC SPECIES OF Dinophysis AND Pseudo-nitzschia IN A SUBTROPICAL BRAZILIAN ESTUARY - Tibiriçá,Carlos Eduardo Junqueira de Azevedo; Fernandes,Luciano Felício; Mafra Junior,Luiz Laureno
This study investigated the spatial and temporal distributions of toxigenic phytoplankton species between October 2010 and April 2012 in Guaratuba Bay, Paraná state, Brazil, where aquaculture has been intensified in recent years. The highest abundances of Pseudo-nitzschia calliantha and P. pungens (up to 7.3 x 104 cells L-1), diatoms which cause amnesic shellfish poisoning (ASP), were correlated with higher values of temperature (from December to April, salinity (>20) and silicate concentrations (ranging from 6.0 to 90.0 µm). The occurrence of these harmful diatoms in the bay also appeared to depend upon the development of seeding mechanisms in the adjacent coastal...

7. SPATIAL AND TEMPORALVARIATION OF DISSOLVED INORGANIC NUTRIENTS, AND CHLOROPHYLL-α IN A TROPICAL ESTUARY IN NORTHEASTERN BRAZIL: DYNAMICS OF NUTRIENT REMOVAL - Silva,Maria Aparecida Macedo; Souza,Marcelo F. L.; Abreu,Paulo C.
Monthly sampling campaigns were carried out between February 2010 and January 2011 to evaluate the spatial and temporal distribution of nutrients (ammonium, nitrite, nitrate, dissolved organic nitrogen, phosphate, dissolved organic phosphorus and silicate) and chlorophyll-α along a salinity gradient in the tropical Cachoeira River estuary, subject to the untreated effluents of a sewage treatment plant (STP). During the study period the lowest and highest river discharge occurred in February and April 2010, respectively. High river outflow promoted increased concentrations of inorganic nitrogen and silicate but did not affect the concentration of phosphate. Based on the chlorophyll-α concentration the estuary may...

8. SHORT-TERM PHYTOPLANKTON DYNAMICS IN RESPONSE TO TIDAL STIRRING IN A TROPICAL ESTUARY (SOUTHEASTERN BRAZIL) - Leles,Suzana Gonçalves; Souza,Catharina Alves de; Faria,Cassia de Oliveira; Ramos,Ana Beatriz; Fernandes,Alexandre Macedo; Moser,Gleyci Aparecida de Oliveira

9. POPULATION BIOLOGY OF SEABOB-SHRIMP Xiphopenaeus kroyeri (Heller, 1862) CAPTURED ON THE SOUTH COAST OF PERNAMBUCO STATE, NORTHEASTERN BRAZIL - Lopes,Danilo Francisco Corrêa; Peixoto,Silvio Ricardo Maurano; Frédou,Flavia Lucena; Silva,Emanuell Felipe Beserra da
This paper aims to describe the population dynamics and to evaluate the stock of the seabob-shrimp Xiphopenaeus kroyeri on the coast of Pernambuco. Sampling was carried out between August/2011 and July/2012 in Sirinhaém, southern coast of Pernambuco. A total of 1201 individuals were analyzed, 673 females and 528 males. Total length (Lt) of females varied from 4.5 to 13.5 cm while the Lt of males ranged between 4.0 and 11.0 cm. The relationship between the Lt and carapace length and Lt and total weight showed negative allometry (males, females and pooled sexes). The slope of the curve "b" was statistically...

10. GROWTH OF Litopenaeus schmitti (BURKENROAD, 1936) AND Farfantepenaeus paulensis (PEREZ-FARFANTE, 1967) SHRIMP REARED IN RECIRCULATION CULTURE SYSTEM - Henriques,Marcelo Barbosa; Alves,Pedro Mestre Ferreira; Barreto,Oscar José Sallée; Souza,Marcelo Ricardo de
The Litopenaeus schmitti and Farfantepenaeus paulensis shrimp captured in estuaries are marketed as live bait for recreational fishing. As an alternative to shrimp extractive activities, the authors evaluated the rearing of these species in a recirculation culture system. For each species, the grow-out study was carried out in two 120-day production cycles, using 3,300 juveniles of an average length of 25 mm and weight of 0.9 grams in each, distributed in 12 tanks of 1,500 liters and 1.32 m2, at a population density of 208.3 shrimp per m2. The growth parameters were obtained using the von Bertalanffy model based on...

11. OXYGEN CONSUMPTION AND AMMONIA EXCRETION OF THE ANTARCTIC AMPHIPOD Bovallia gigantea PFEFFER, 1888, AT DIFFERENT TEMPERATURES AND SALINITIES - Gomes,Vicente; Passos,Maria José de Arruda Campos Rocha; Rocha,Arthur José da Silva; Santos,Thais da Cruz Alves dos; Hasue,Fabio Matsu; Ngan,Phan Van
The energy budget of Antarctic stenothermic and/or stenohaline ectotherms is modulated by variations of temperature and salinity. The joint effects of these latter on polar organisms have been but little studied. Data on this subject are of great importance for an understanding of the energy demand of Antarctic animals such as amphipods, especially when considering their ecological importance and the possible impacts of global changes. Experiments were carried out at the Brazilian Antarctic Station "Comandante Ferraz" under controlled conditions. Specimens of Bovallia gigantea were collected in Admiralty Bay and acclimated to temperatures of 0ºC; 2.5ºC and 5ºC and to salinities...

12. FEEDING AND REPRODUCTIVE ACTIVITY OF THE COPEPODS Drepanopus forcipatus AND Calanus australis DURING LATE SUMMER ON THE SOUTHERN PATAGONIAN SHELF (ARGENTINA, 47°-55°S) - Antacli,Julieta Carolina; Sabatini,Marina E.; Silva,Ricardo I.; Hernández,Daniel R.; Jaureguizar,Andrés J.; Akselman,Rut
Drepanopus forcipatus and Calanus australis are key planktonic copepods on the southern Patagonian shelf. Their feeding and reproductive patterns and population status were investigated during late summer, when environmental conditions may be critical. The presence of food in the gut and food-pellet length were recorded in adult females and the most abundant copepodite stages. Diet composition was also studied in adult females. Female reproductive status was evaluated by gonad staging. Despite generally low feeding conditions and decreasing seasonal temperature, both copepods fed to some degree. The most numerous copepodites and adult females of both species showed similarly low feeding activity....

13. SEASONAL ASSESSMENT OF HYDROGRAPHIC VARIABLES AND PHYTOPLANKTON COMMUNITY IN THE ARABIAN SEA WATERS OF KERALA, SOUTHWEST COAST OF INDIA - Rai,Sushanth Vishwanath; Rajashekhar,Madaiah
The seasonal variation of the hydrographic variables and phytoplankton species in the Arabian Sea waters of the Kerala coast, Southern India was investigated during different seasons. The variables such as pH, temperature, salinity, turbidity and chlorophyll-a contents of water were found to be high during pre-monsoon season and the dissolved oxygen content was minimal. The concentration of nutrients viz., nitrate, phosphate, silicate varied independently. In the study a total of 53 species of phytoplankton were recorded. Their density was higher during the post-monsoon season than during other seasons and the diatoms were found to be the dominant species. The major...

14. HYDRODYNAMICS AND BIO-OPTICAL ASSESSMENT OF TWO PRISTINE SUBTROPICAL ESTUARIES IN SOUTHERN BRAZIL - Noernberg,Mauricio Almeida; Mizerkowski,Byanka Damian; Paloschi,Nicole Gabriele; Bento,Joaquim Pereira
Measuring small-scale physical processes and how they affect the spatial patterns of sea water's optical constituents plays a key role in understanding the functioning of complex coastal ecosystems such as estuaries. The spatial variations of physical and bio-optical water properties were investigated during one spring tidal cycle in austral summer, on two transects across the channel of the Medeiros and Itaqui sub-estuaries. These sub-estuaries are a biosphere reserve, and part of the Paranaguá Estuarine System, located on the Southern Brazilian coast. Both sub-estuaries were classified as Type 1a, wellmixed with low stratification. The salinity variations are in phase with the...

15. SURVIVAL ESTIMATES OF BYCATCH INDIVIDUALS DISCARDED FROM BIVALVE DREDGES - Leitão,Francisco; Range,Pedro; Gaspar,Miguel Baptista
The fate of released bycatch is an issue of great interest for fisheries research and management. Survival experiments were carried out to assess the survival capacity of animals damaged and discarded during clam dredging operations. Three common bycatch species, two fish (Trachinus vipera; Dicologlossa cuneata) and one crab (Polybius henslowii), were collected during the sorting of catches from a commercial dredging boat. An arbitrary score scale was used to quantify the type and extent of damage to the organisms. Onboard, damaged individuals were placed in tanks containing seawater which were subsequently transferred to the laboratory. Survival experiments were conducted during...

16. THE INFLUENCE OF TIDAL AND RAINFALL CYCLES ON INTERTIDAL NEMATODES: A CASE STUDY IN A TROPICAL SANDY BEACH - Venekey,Virag; Santos,Paulo Jorge Parreira dos; Fonsêca-Genevois,Verônica Gomes da
The present study describes the nematode assemblage of the bay of Tamandaré (Brazil), a tropical sandy beach, during the low, flood, high and ebb tides of two consecutive tidal cycles in four different months of the year (May, July, September and November). The nematode assemblage was dominated by Metachromadora and Perepsilonema and varied significantly between months and tides. Densities were lower in July, and changes in assemblage structure occurred during the transitional periods between rainy and dry months, which showed the influence of rainfall. Flood and ebb tides appeared to exercise the greatest influences over the tidal cycle, although the...

17. A LPUE (LANDING PER UNIT EFFORT) ANALYSIS OF THE TRAWL FISHERY FOR THE COASTAL SHRIMPS Artemesia longinaris AND Pleoticus muelleri OFF SOUTHERN BRAZIL - Metri,Cassiana Baptista; Perez,José Angel Alvarez
The Argentine stiletto shrimp (Artemesia longinaris) and the Argentine red shrimp (Pleoticus muelleri) currently sustain an important fishery in terms of tonnage and revenues in southern Brazil. This study analyzed the factors affecting the abundance of both species through the application of Generalized Linear Models to landing-per-unit-of-effort (LPUE) data of the trawl fleet operating on the main fishing grounds between 1998 and 2005. The main patterns of LPUE variability of both species were attributed do the effect of seasons and annual cycles. Larger yields were obtained in the southern shallow areas of Rio Grande do Sul State. No tendency either...

18. Variations of mesozooplankton composition in a eutrophicated semi-enclosed system (Encerrada Bay, Tierra del Fuego, Argentina) - Biancalana,Florencia; Torres,Amèrico I.

19. Spatio-temporal distribution and target species in a longline fishery off the southeastern coast of Brazil - Mourato,Bruno L.; Arfelli,Carlos A.; Amorim,Alberto F.; Hazin,Humberto G.; Carvalho,Felipe C.; Hazin,Fábio H. V.
In the present study, a cluster analysis, in relation to the species composition of the catches, was used to classify 6,486 fishing sets by a longline fleet based in São Paulo State, Brazil, from 1998 to 2006. Based on the proportions of 12 species and three broader species groups, three clusters were identified: C1: other fishes; C2: blue shark; C3: swordfish. Results indicated that the fleet targeted mainly blue shark and swordfish and also showed that the blue shark importance in this fishery has been growing progressively trough the years. Offshore areas were exploited mainly in the first and fourth...

20. Fishery biology of the swordfish (Xiphias gladius, Linnaeus 1758) caught by surface longliners based in Itajaí, southern Brazil - Quaggio,Ana Lia Campos; Lessa,Rosângela P. T.; Kotas,Jorge Eduardo; Lin,Celson F.
The Xiphias gladius (Linnaeus, 1758) data used in the present study were obtained from commercial fishing cruises of the pelagic longline fleet based in Itajaí, operating in the Southwest Atlantic. For the Covariance models, fishing effort (number of hooks) and catches (kg) were pooled and categorized into the following groups: (1) year (1997, 1998, 2001, 2002 and 2007); (2) lunar phase; and (3) seasons, fishing effort being the covariate. The highest mean swordfish catch (kg) occurred during the waxing crescent moon and during wintertime. The Mantel-Haenszel procedure was applied to compare the efficiency of the two hooks tested, and showed...

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