IECOS - Instituto de Estudos Costeiros/Campus Bragança

URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/2228

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Agora exibindo 1 - 13 de 13

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Características sedimentares fluviais associadas ao grau de preservação da mata Ciliar - Rio Urumajó, Nordeste Paraense
(Instituto Nacional de Pesquisas da Amazônia, 2009-03) BRITO, Roney Nonato Reis de; ASP NETO, Nils Edvin; BEASLEY, Colin Robert; SANTOS, Helane Súzia Silva dos
Rivers are the main ways of sediment transport from inland to the coastal zone and oceans. Despite direct influence of climate, the vegetation coverage plays a central role in liquid and solid fluvial discharge. In this context, the present work aimed to study the fluvial sedimentology of the Urumajó River (Pará, Brazil) in relation to the preservation state of riparian vegetation. Sediment samples were collected at five sites (A to E), including a five-sample transversal profile at each site. The sites were distributed from the source to the estuarine area. The characteristics and preservation state of the riparian vegetation were analyzed at each site as well. The collected sediments were submitted to grain size analysis, where mean grain size, median, asymmetry, selection and kurtosis were obtained. The results made it possible to recognize the regular characteristics (sites A and C), which included median sand as the main sediment class and well-sorted and approximate symmetric grain size distribution, directly related to the well-preserved riparian vegetation at sites A and C. On the other hand, sites B, D and E showed substantial differences in relation to the regular pattern. This fact could be associated to the vegetation degradation at those sites, resulting in margin erosion. Furthermore, at site E, reflexes of tide influence on the sediment characteristics could be observed, subsidizing the estuary delimitation.
Acesso aberto (Open Access)
Chemometric identification and nutritional evaluation of three species of Lutjanidae (Perciformes) from the Amazonian Atlantic Coast based on fatty acid profiles
(Instituto Nacional de Pesquisas da Amazônia, 2016-12) ALMEIDA, Edilene Santos de; SILVA, Evaldo Martins da
The fatty acid (FA) profiles of fish species with a similar genetic or geographic origin are important quality parameters that attract bioecological interest because they are inﬂuenced by the nutritional habits of the species. The aim of this study was to determine the proximate compositions and FA profiles of heart, brain and muscle tissues from three fish species (Lutjanus purpureus, Lutjanus synagris and Ocyurus chrysurus) captured from the Amazonian Atlantic Coast. In addition to performing nutritional analysis of the FA profiles, principal components analysis (PCA) was performed as a chemometric tool to discriminate among the species. Lutjanus synagris had the highest protein content (18.23%), while O. chrysurus possessed the highest lipid content (4.25%). All of the nutritional quality parameters (the n-6/n-3 and Σ polyunsaturated FA/Σ saturated FA ratios and dietary indices of atherogenicity and thrombogenicity) of the FA profiles of the three species are of interest to consumers. In general, the predominant FA in the tissues of all species analyzed was palmitic acid, followed by stearic acid. Oleic acid was predominant among the monounsaturated FAs, while docosahexaenoic acid was the most prevalent polyunsaturated FA. Chemometric analysis was an effective tool for fish identification. PCA showed that the FA profiles of the brain tissues were optimal for discriminating among the species, with O. chrysurus showing the most different FA profile from the others. The muscle FA profile was the most useful for identifying L. purpureus.
Acesso aberto (Open Access)
Crescimento de mudas de mangue sob diferentes níveis de sombreamento na península de Ajuruteua, Bragança, Pará
(Instituto Nacional de Pesquisas da Amazônia, 2013-09) LOPES, Elaine Cristina; ARAÚJO, Erneida Coelho de; COSTA, Rejane Silva da; DAHER, Rogerio Figueiredo; FERNANDES, Marcus Emanuel Barroncas
The purpose of this study was to evaluate the influence of different levels of shading on the development of seedlings of three mangrove species (Avicennia germinans (L.) Stearn., Rhizophora mangle L. and Laguncularia racemosa (L.) Gaertn. f.). The experiment was conducted at the community of Tamatateua, Ajuruteua peninsula, Bragança, PA, Brazil. For seedling production, the propagules and seeds of the mangrove species were planted in polyethylene bags (17 x 27 cm), filled with a typical mangrove substrate. The seedlings of the three species were grown under full sun (0), 30% and 60% shading, in a completely randomized design, a 3 x 3 factorial (three species and three shading levels), with eight seedlings per replication. After nine months under shading, plant samples were taken. The variables evaluated were: the shoot/height ratio, stem diameter, shoot dry matter, stem mass, root dry matter, total dry mass matter and morphological indices. Growth of seedlings of R. mangle occurred at all light levels. Seedlings of A. germinans grew faster at full sun and at 30% shading. Whereas, seedlings of L. racemosa were able to grow at 30 and 60% shading, but they also grew faster at full sunlight.
Acesso aberto (Open Access)
Developmental morphology of mouthparts and foregut of the larvae and postlarvae of Lepidophthalmus siriboia Felder & Rodrigues, 1993 (Decapoda: Callianassidae)
(Instituto Nacional de Pesquisas da Amazônia, 2006) ABRUNHOSA, Fernando Araujo; MELO, Marlon Aguiar; LIMA, Jô de Farias; ABRUNHOSA, Jacqueline Pompeu
In this study, the gross morphology of the mouthparts and foregut of the ghost shrimp Lepidophthalmus siriboia were investigated from larvae and postlarvae reared in the laboratory. The mouthparts (maxillae and maxillipeds) of the zoeae have a reduced number of setae and spines (or is absent in some individuals), and the foregut, under developed, have few minute setae in the cardiac and pyloric chambers. In contrast, after the metamorphosis into megalopa stage, all feeding appendages have many setae and, the foregut shows a well-developed gastric mill with strong lateral teeth. In the juvenile stage occurs an increase of setae and spines in the mouthparts and the foregut becomes more specialized. These observations strongly suggest that a lecithotrophic development occurs during all zoeal stages but the megalopa and juvenile stages are feeding animals. The functional morphology of the feeding structures of L. siriboia and other decapods will be briefly discussed.
Acesso aberto (Open Access)
O efeito da salinidade no desenvolvimento larval do caranguejo-uçá, Ucides cordatus (Linnaeus, 1763) (Decapoda: Ocypodidae) no Norte do Brasil
(Instituto Nacional de Pesquisas da Amazônia, 2008) SIMITH, Darlan de Jesus de Brito; DIELE, Karen
The present work studied the effect of salinity on the survival and duration of larval development of the mangrove crab, Ucides cordatus (from the Caeté River estuary, North of Brazil) until the megalopal phase in seven salinity treatments (0, 5, 10, 15, 20, 25 e 30). Salinity significantly affected the survival of the zoea larvae, however it did not affect the duration of the larval development (20.77 ± 1.56 days). In salinity 0, 5 and 10 all zoea larvae died. Only from off salinity 15, complete development until the megalopal phase occurred. The survival rate was highest in salinity 30 (72%) and lowest in 15 (16%). The reduced survival rate of the U. cordatus zoea larvae, in low salinities, indicates the necessity of larval dispersion from the estuary to coastal waters, where salinity conditions for larval development are more favorable. Otherwise, if there was no dispersion, the reduced salinity of estuarine waters in the rainy season would cause a high mortality thereby affecting the recruitment, maintenance and growth of the U. cordatus population in the mangroves.
Acesso aberto (Open Access)
Efeitos do tratamento com formalina e sulfato de cobre sobre os parâmetros hematológicos e parasitos monogenéticos em juvenis de Hemigrammus sp. (Osteichthyes: Characidae)
(Instituto Nacional de Pesquisas da Amazônia, 2013-06) PAIXÃO, Luciana Farias; SANTOS, Rudã Fernandes Brandão; RAMOS, Fabrício Menezes; FUJIMOTO, Rodrigo Yudi
The objective of this study was to evaluate the effectiveness of formalin and copper sulphate to controlm onogeneans injuvenile Hemigrammus spand its effect on leukocyte count. We used acompletely randomized design with five treatments and three replications. All treatments lasted for three days and consisted of: T1, control; T2 and T3 immersion bath for one hour in formalin, an of two concentrations of 0.25ml formalin and the other 0.1mlL-1; the T4 bath for 24 hours with 0,025 ml of formalin-L -1; and T5, bath 24 hours with copper sulphate (0.3 mgL-1). After the experimental period was observed that T2, 100% mortality. The T3 and T5 provided 100% efficiency, however, fish presented mortalities and intoxication of the 66 and 80% respectively. T4 showed an efficacy of 77.7% and decrease in parasitological indices: total number of parasites of 11, 3 ± 9, mean infection intensity of 3.2 ± 2 and a prevalence of 47.1%. As the leukocytes was observed that at T3, T4 and T5 occurred differences in the proportionof lymphocytes, monocytes and neutrophilsas compared to control. The CuSO4 and formalin reduce the parasite load, but presented to be toxicat higher concentrations.
Acesso aberto (Open Access)
Larval development of Lepidophthalmus siriboia Felder & Rodrigues, 1993 (Decapoda: Thalassinidea) from the Amazon region, reared in the laboratory
(Instituto Nacional de Pesquisas da Amazônia, 2005) ABRUNHOSA, Fernando Araujo; PIRES, Marcus Alexandre Borges; LIMA, Jô de Farias; COELHO FILHO, Petrônio Alves
The complete larval development of the ghost shrimp Lepidophthalmus siriboia Felder & Rodrigues, 1993 was described and illustrated in detail from specimens reared in the laboratory. Ovigerous females were collected at Canela Island in the northeastern region of the State of Pará. The larvae hatch as a prezoea, in which they persist for less than 3 hours. The larval development consists of three zoeal stages and a megalopa. The zoeal development averaged from 69 to 111 hours. The period in the megalopa stage was about 185 hours (about 8 days). The percentage of individuals succeeding in molt into juvenile stage was 91,8%. The first juvenile stage was reached 254 hours (about 10 days) after hatching. Morphological comparisons and their relationship with larvae of congeneric species are briefly discussed.
Acesso aberto (Open Access)
Mangrove sedimentary characteristics and implications for crab Ucides cordatus (Crustacea, Decapoda, Ucididae) distribution in an estuarine area of the Amazonian region
(2013-12) GOMES, José Diego; ABRUNHOSA, Fernando Araujo; SIMITH, Darlan de Jesus de Brito; ASP NETO, Nils Edvin
At the coastal zone sediments, water and organisms interact intensely. At equatorial tidal-dominated coast mangroves are abundant. These areas are well-known for their ecological importance. Considering the mangroves of Atlantic South America, the mangrove crab, Ucides cordatus has ecological and economic prominence. High densities of this crab are found on the Amazon coast. This study investigates the sediment distribution of the Bragança mangrove area (Amazon coast, Brazil) and its correlations with vegetation and mangrove crab distribution. Sediments of 47 sites, as well as crabs from sites with different sediment and vegetation, were sampled. Results show that surface sediment of the area is mainly composed by silt (59%), with 21% sand and 20% clay. Variations in sorting and skewness are the product of local variations in clay and sand content. The vegetation type was significantly correlated to mangrove crab characteristics, abundance and weight/size. Sediment characteristics are also substantially different according to the vegetation type. Areas where Avicennia germinans prevails have more sand and clay than areas of Rizophora mangle, in which silt is dominant and crabs were significantly heavier. The present results have showed that the distribution of sediments, crabs and vegetation at mangrove areas are strongly correlated. Thus, they should be studied in conjunction.
Acesso aberto (Open Access)
Mangrove vegetation in Amazonia: a review of studies from the coast of Pará and Maranhão States, north Brazil
(Instituto Nacional de Pesquisas da Amazônia, 2008) MENEZES, Moirah Paula Machado de; BERGER, Uta; MEHLIG, Ulf
The present study is a compilation of the literature about vegetation of mangrove forest of the north coast of Brazil. It synthesizes the knowledge about this important ecosystem and lists the currently available literature. The study focuses on the coast of Pará and Maranhão states, which are covered by a continuous belt of mangroves. The mangrove flora comprises six mangrove tree species and several associated species. Mangrove tree height and stem diameter vary as a function of abiotic local stand parameters. Seasonal variation in rainfall and salinity affect the species' phenology and litter fall. Local population use products derived from mangrove plants for different purposes (e.g. fuel; medicinal; rural construction). The increase in the coastal population has given rise to conflicts, which impact on mangrove forest.
Acesso aberto (Open Access)
The morphology of the foregut of larvae and postlarva of Sesarma curacaoense De Man, 1892: a species with facultative lecithotrophy during larval development
(Instituto Nacional de Pesquisas da Amazônia, 2006) MELO, Marlon Aguiar; ABRUNHOSA, Fernando Araujo; SAMPAIO, Maria Iracilda da Cunha
Previous study on the resistance of larvae of Sesarma curacaoense submitted to starvation has revealed a facultative lecithotrophy during zoeal stages, but megalopa and first juvenile stages are exclusively feeding stages. In the present study, the gross morphology and fine structure of the foregut of S. curacaoense were investigated during larval, megalopa and first juvenile stages. The foregut of the zoea I show specific setae and a filter press apparently functional. The foregut undergoes changes in the zoea II (last larval stage) with increment of setae number, mainly on the cardiopyloric valve and complexity of the filter press. After metamorphosis to megalopa stage the foregut become rather complex, with a gastric mill supporting a medial and two lateral teeth well-developed. The foregut of the first juvenile is more specialized compared to the previous stage, showing similar characteristics of the decapod adults. These results provide further evidence of facultative lecithotrophic development in the larvae of S. curacaoense.
Acesso aberto (Open Access)
New records of Fredius denticulatus (H. Milne-Edwards, 1853) and F. reflexifrons (Ortmann, 1897), and the eastern limits of the distribution of pseudothelphusid crabs (Crustacea: Decapoda) in Brazil
(Instituto Nacional de Pesquisas da Amazônia, 2005) MAGALHÃES FILHO, Célio Ubirajara; ABRUNHOSA, Fernando Araujo; PEREIRA, Milena de Oliveira; MELO, Marlon Aguiar
The occurence of Fredius reflexifrons (Ortmann, 1897), a pseudothelphusid crab widely distributed in the Amazon region and the Atlantic Guianas, is recorded from the state of Ceará, northeastern Brazil. Other records of this species and Fredius denticulatus (H. Milne-Edwards, 1853) from the Amazon region are also presented. A discussion is made on the eastern limits of the distribution of the family Pseudothelphusidae in Brazil.
Acesso aberto (Open Access)
Observações hidrológicas e resultados de modelagem no espalhamento sazonal e espacial da pluma de água Amazônica
(Instituto Nacional de Pesquisas da Amazônia, 2009) SILVA, Alex Costa da; SANTOS, Maria de Lourdes Souza; ARAUJO, Moacyr Cunha; BOURLÈS, Bernard
In this study, we present surface synoptic data collected during four oceanographic cruises undertaken in March-April 1995, October-November 1997, April-May 1999 and August-September 2001 in the Brazilian Program “REVIZEE/SCORE-NO” and a combination of model results (1/6 deg.). The emphasis of this paper is to point out the monthly changes on the spreading of the Amazon plume over the external Amazon shelf area and the eastern region of the Amazon River. Hydrographic data and model results demonstrated that during March-May, the Amazon plume moved southwestward along the northern coast of Brazil, decreasing during August-September; but this was not observed during October-November. Model results revealed ring signatures shedding from the North Brazil Current (NBC). Results also showed that during August the Amazon plume encircling the NBC retroflection was around 7º N.
Acesso aberto (Open Access)
Seasonality of nematode larvae in Iguanodectes spilurus (Characidae) an ornamental fish from northeastern Para, Brazil
(Instituto Nacional de Pesquisas da Amazônia, 2013-12) FUJIMOTO, Rodrigo Yudi; ANJOS, Ellem Cristina Silva dos; RAMOS, Fabrício Menezes; MARTINS, Maurício Laterça
The current study presents a parasitological survey of larval nematodes from freshwater ornamental fish Iguanodectes spilurus caught in the watercourse of the Caete River, in the northeast region of the State of Para, Brazil. A total of 176 specimens, 1.36±0.75 g weight and 5.53±0.98 cm total length, were analyzed. Nematode larvae were identified as Capillaria sp., Procamallanus sp. and Anisakidae, with prevalence of 70.45% and infection intensity ranging from 1.81 to 4.70 larvae. The highest prevalence 57.38% occurred in the liver, but no seasonality was observed, indicating high infection throughout the year. Seasonality was observed in fish parasitized in the stomach, intestine and caecum, with prevalence and mean intensity of 17.61% and 2.32 parasites, 12.5% and 1.81 parasites, 10.79% and 2.21 parasites, respectively. The highest degree of infection was observed in the rainy season, probably due to increased availability of intermediate hosts or food.

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