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SciELO Brasil - Scientific Electronic Library Online (76,895 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 64

1. 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

2. 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...

3. 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...

4. 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...

5. 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....

6. 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...

7. 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...

8. 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...

9. 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...

10. 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...

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

12. 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...

13. 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...

14. Liver damages and nuclear abnormalities in erythrocytes of Atherinella brasiliensis (Actynopterigii, Atherinopsidade) from two beaches in Southeast of Brazil - Fernandez,Welingtom S.; Dias,June Ferraz; Ribeiro,Ciro Alberto Oliveira; Azevedo,Juliana de Souza
There are few environmental studies using biomarkers for the species Atherinella brasiliensis in Brazil. In the present work, the presence of hepatic histopathological lesions and nuclear abnormalities in erythrocytes were investigated in A. brasiliensis from Lamberto, a beach under influence of domestic wastes and marine activities. For comparison, fish were also sampled in Puruba, a non-polluted beach, located in the northeastern of São Paulo State. The frequency of lesions found in liver was in higher numbers in individuals from Lamberto than Puruba beach. The most critical injuries observed in A. brasiliensis were the presence of necrotic areas, leucocytes infiltration and...

15. Recruitment of mud clam Polymesoda erosa (Solander, 1876) in a mangrove habitat of Chorao island, Goa - Clemente,Sandhya; Ingole,Baban
Habitat-specific settlement success results either from active habitat selection or differential mortality after non-selective settlement. The mud clam Polymesoda erosa (Solander, 1876) is an ecologically and economically important benthic invertebrate with high abundance in the mangrove forests of Chorao Island, Goa, India. A one-year study (Jul 2004-Jul 2005) was conducted to characterize the patterns of post-larval settlement and survival of P. erosa in the mangrove habitat. The mean density of settling post-larvae was 28 no.m-2 with a majority of settlers during Sept 04. The density of adult clams in the landward zone ranged from 7-12 no.m-2 (mean: 9 ± 6...

16. Temporal variation in vegetative development of Caulerpa scalpelliformis (Chlorophyta) from Baleia beach, Ilha Grande bay (Rio de janeiro, brazil) - Vasconcelos,Marcelo Augusto; Schubart,Carolina Leite Queiroga; Széchy,Maria Teresa Menezes de
Caulerpa scalpelliformis grows on rocky and sandy bottoms at different depths in Jacuacanga Cove, Ilha Grande Bay, where it can form dense patches. The invasive behavior of this and other species of Caulerpa is well documented in the literature. This study analyzed the variation of the vegetative development of C. scalpelliformis from Baleia Beach (23º01'63''S and 44º14'18''W) in Jacuacanga Cove, from June 2003 to September 2004, including plants from rocky and sandy substrates. Morphometric and dry weight data from the erect and prostrate portions were used. Plants were collected from 20 x 20 cm² plots (n=3), randomly positioned on the...

17. The co-influence of the sea breeze and the coastal upwelling at Cabo Frio: a numerical investigation using coupled models - Ribeiro,Flávia Noronha Dutra; Soares,Jacyra; Oliveira,Amauri Pereira de
A coupled atmospheric-oceanic model was used to investigate whether there is a positive feedback between the coastal upwelling and the sea breeze at Cabo Frio - RJ (Brazil). Two experiments were performed to ascertain the influence of the sea breeze on the coastal upwelling: the first one used the coupled model forced with synoptic NE winds of 8 m s-1 and the sign of the sea breeze circulation was set by the atmospheric model; the second experiment used only the oceanic model with constant 8 m s-1 NE winds. Then, to study the influence of the coastal upwelling on the...

18. Coral community structure and sedimentation at different distances from the coast of the Abrolhos Bank, Brazil - Segal,Bárbara; Castro,Clovis B.
Sedimentation has previously been considered an important source of impact in coral reefs. We compared 3 sites on the Abrolhos Bank, Brazil, regarding sedimentation rates, carbonate sediment composition, coral cover, and colony size for the commonest local coral species (Mussismilia braziliensis, Siderastrea stellata, and Favia gravida). The sites are located at different distances from the mainland: Pedra de Leste (14 km), Pontas Sul (26 km), and Parcel dos Abrolhos (58 km). Sedimentation was higher in winter (p <0.05), but no difference among sites was noted. Sites differed in sediment type (P <0.05), with Parcel dos Abrolhos showing nearly 90% of...

19. Organotin pollution at Arraial do Cabo, Rio de Janeiro State, Brazil: increasing levels after the TBT ban - Toste,Raquel; Fernandez,Marcos Antônio; Pessoa,Igor de Araújo; Parahyba,Mateus Alves; Dore,Marina Pereira
Imposex, an endocrine disruption phenomenon, is a biomarker of tributyltin (TBT) exposure in marine gastropod populations. The occurrence and intensity of the syndrome in populations of the neogastropod Stramonita haemastoma were ascertained at nine sampling stations in October 2008 at Arraial do Cabo, a very important tourist resort in Rio de Janeiro state (Brazil) and part of the Marine Extractive Reserve of Arraial do Cabo. The results obtained made it possible to evaluate the changes which had occurred since the last biomonitoring campaign, undertaken in 2001, at these same stations. Despite the ban on the use of TBT imposed by...

20. Ichthyoplankton distribution and abundance in the northern Todos os Santos and Camamu Bays, Bahia State - Brazil - Katsuragawa,Mario; Zani-Teixeira,Maria de Lourdes; Goçalo,Cássia Gôngora; Ohkawara,Marcio Hidekazu; Itagaki,Michael Kengo
The occurrence, distribution and abundance of ichthyoplankton in Todos os Santos and Camamu Bays were analyzed based on four samplings (winter 2003, summer 2003, winter 2004 and summer 2005). Samples were obtained by surface horizontal hauls, using a 200-µm mesh conical-cylinder plankton net. The distribution and abundance of eggs indicate a remarkable seasonal and annual variation of spawning activity in the region, especially when the two summer campaigns are compared. In summer 2003 the highest quantitative values were recorded, especially for Camamu, where the maximum reached 106.56 eggs.m-3, with an overall average of 43.46 eggs.m-3 for the two areas. In...

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