876 resultados para Hewlett Bay Park
Resumo:
Structure of intertidal and subtidal benthic macrofauna in the northeastern region of Todos os Santos Bay (TSB), northeast Brazil, was investigated during a period of two years. Relationships with environmental parameters were studied through uni-and multivariate statistical analyses, and the main distributional patterns shown to be especially related to sediment type and content of organic fractions (Carbon, Nitrogen, Phosphorus), on both temporal and spatial scales. Polychaete annelids accounted for more than 70% of the total fauna and showed low densities, species richness and diversity, except for the area situated on the reef banks. These banks constitute a peculiar environment in relation to the rest of the region by having coarse sediments poor in organic matter and rich in biodetritic carbonates besides an abundant and diverse fauna. The intertidal region and the shallower area nearer to the oil refinery RLAM, with sediments composed mainly of fine sand, seem to constitute an unstable system with few highly dominant species, such as Armandia polyophthalma and Laeonereis acuta. In the other regions of TSB, where muddy bottoms predominated, densities and diversity were low, especially in the stations near the refinery. Here the lowest values of the biological indicators occurred together with the highest organic compound content. In addition, the nearest sites (stations 4 and 7) were sometimes azoic. The adjacent Caboto, considered as a control area at first, presented low density but intermediate values of species diversity, which indicates a less disturbed environment in relation to the pelitic infralittoral in front of the refinery. The results of the ordination analyses evidenced five homogeneous groups of stations (intertidal; reef banks; pelitic infralittoral; mixed sediments; Caboto) with different specific patterns, a fact which seems to be mainly related to granulometry and chemical sediment characteristics.
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The aim of this study was to analyze the distribution and abundance of the fish fauna of Palmas bay on Anchieta Island in southeastern Brazil. Specimens were caught in the summer and winter of 1992, using an otter trawl at three locations in the bay. The specimens were caught in both the nighttime and daytime. Data on the water temperature and salinity were recorded for the characterization of the predominant water mass in the region, and sediment samples were taken for granulometric analysis. A total of 7 656 specimens (79 species), with a total weight of approximately 300 kg, were recorded. The most abundant species were Eucinostomus argenteus, Ctenosciaena gracilicirrhus, Haemulon steindachneri, Eucinostomus gula and Diapterus rhombeus, which together accounted for more than 73% of the sample. In general, the ecological indices showed no differences in the composition of species for the abiotic variables analyzed. The multivariate analysis showed that the variations in the distribution of the fish fauna were mainly associated with intra-annual differences in temperature and salinity, resulting from the presence of South Atlantic Central Water (SACW) in the area during the summer. The analysis also showed an association with the type of bottom and a lesser association with respect to the night/day periods.
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The community structure and dynamics as well as some biological parameters of selected species of the ichthyofauna of the Mataripe estuarine region affected by the Landulfo Alves Oil Refinery (RLAM) were analyzed. Twenty stations were sampled with a gillnet in five different periods: August and December 2003, March and July/August 2004 and January 2005. Thirty-five actinopterygian species and one elasmobranch species were recorded, Oligoplites saurus, Diapterus rhombeus, Lutjanus synagris and Scomberomorus brasiliensis among them, on all the campaigns. A total of 1368 specimens, weighing 36.10 kg, were caught. The ichthyofauna total biomass was greater, in weight, on the eastern side of the study region, especially at the stations close to the shoals/reefs and the rocky bottom. A similar pattern was also observed for the diversity values. In general, low evenness and diversity were observed in the area studied, possibly as a result of the fishing gear used. D. rhombeus juveniles dominated in all but one of the samplings (July 2004), in which latter Cyclichthys spinosus was dominant. Carangids and species associated with consolidated bottoms were observed, although in small numbers, throughout the study period. In spite of the limitations imposed by the gear used for sampling, the estuarine area influenced by the RLAM was seen to play a role as a growth area for the great majority of species, especially the mojarra (D. rhombeus), but it offers no fishing potential due to the prevalence of young and small individuals. Evidence of imminent spawning was recorded for Pomadasys corvinaeformis in August 2003, and recent spawning in March 2004 for Oligoplites saurus. Further, mature individuals occurred in insufficient numbers to permit population level evaluation.
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Information on marine and estuarine capture fishery activity in northern Todos os Santos Bay, northeastern Brazil, based on daily data collected between September 2003 and June 2005 is presented. Small-scale artisanal fishery in this area includes the use of traditional vessels both nonmotorized and motorized for locomotion, being carried out mainly by canoe or on foot, and involves many different kinds of gear, including gillnet, hook and line, seine nets, and traps. A total of 113 taxa were grouped into 77 resources, including 88 fish, 10 crustaceans, and 15 mollusks. Data on nominal catches of fish, crustaceans and mollusks are presented by month and location. A total of 345.2 tonnes of fishery resources were produced (285.4 tonnes of fish, 39.2 tonnes of fresh invertebrates, and 20.6 tonnes of processed invertebrates). Temporal variation in the fish catch was associated with the life cycle of the species or with the hydrographic conditions. The first-sale value of this catch amounted to around US$ 615,000.00, fishes representing 71.3% of it. A table of the average price of each fishery resource is presented. The results produced in this study may be considered a reference for future monitoring programs of fishery resources in the area.
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This paper presents the results of the planform stability classification for the headland-bay beaches of the State of Santa Catarina and of the Northern Coast of São Paulo, based on the application of the Parabolic Bay-Shape Equation (PBSE) to aerial images of the beaches, using the software MEPBAY®. For this purpose, georeferenced mosaics of the QuickBird2® satellite imagery (for the State of Santa Catarina) and vertical aerial photographs (for the northern coast of São Paulo State) were used. Headland-bay beach planform stability can be classified as: (1) in static equilibrium, (2) in dynamic equilibrium, (3) unstable or (4) in a state of natural beach reshaping. Static equilibrium beaches are the most frequent along the coast of the State of Santa Catarina and the Northern Shore of São Paulo, notably along the most rugged sectors of the coast and those with experiencing lower fluvial discharge. By comparison, dynamic equilibrium beaches occur primarily on the less rugged sectors of the coast and along regions with higher fluvial discharge. Beaches in a state of natural beach reshaping have only been found in SC, associated with stabilized estuarine inlets or port breakwaters. However, it is not possible to classify any of these beaches as unstable because only one set of images was used. No clear relation was observed between a beach's planform stability and other classification factors, such as morphodynamics or orientation.
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The results obtained in the August and December 2003, August 2004 and January 2005 oceanographic campaigns in the northern region of the Todos os Santos Bay (lat. 12º44.5'S; long. 038º35.00'W) between the Madre de Deus and Maré islands are analyzed. Instruments of continuous and discrete samplings were used to measure hydrographic properties currents and tides. The water mass of the northern region of the bay is forced by semidiurnal and mesotides of form number 0.08 and the lunar component M2 height was estimated at 91cm. The time series of the surface currents indicated movements in the N/S direction, forced by the tide with maximum magnitudes of 0.73 m.s-1 on the December 2003 campaign. However, in August 2004 the currents were dominated by the wind stress forcing, with a maximum speed of 1.85 m.s-1 and SE direction. Near the bottom, the influence of the tide is not as evident, with a decrease in intensity due to internal and bottom friction, with a maximum velocity of 0.17 m.s-1. The thermal and haline structures were weakly horizontally, as well as vertically stratified, with extreme values varying in the intervals 23ºC (August, 2004) to 28ºC (December, 2003) and 31.0 psu (August, 2003) to 36.0 psu (December, 2003), respectively. Some conclusions may be drawn from these results: i) The signs of the dilution of the fresh water discharges of the Caípe, Mataripe and São Paulo rivers in the region under the influence of the RLAM were observed only during the winter periods, but in the summer the region was flooded by waters of oceanic origin and the salinities above 36.0 indicated TW mass intrusion; ii) The N-S circulation near the RLAM is strongly dominated by the tide, and the importance of the M2 component was unequivocal, however, the E-W component presented some tidal modulation away from abrupt bottom topographical changes, and iii) The residual series, calculated as the difference between the original and modeled, is about ¼ of the original and confirmed its semidiurnal character.
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Thirty-eight stations were sampled in Guanabara Bay, Rio de Janeiro, Brazil, to assess the spatio-temporal diversity and biomass of sublittoral polychaetes. Samples were collected during the dry (September 2000) and rainy season (May 2001) in shallow sublittoral sediments. The polychaete spatial composition showed a heterogeneous distribution throughout the bay. A negative gradient of diversity and biomass was observed towards the inner parts of the bay and sheltered areas. A wide azoic area was found inside the bay. Some high-biomass and low-diversity spots were found near a sewage-discharge point. In these areas, the polychaete biomass increased after the rainy season. A diversified polychaete community was identified around the bay mouth, with no dramatic changes of this pattern between the two sampling periods. Deposit-feeders were dominant in the entire study area. The relative importance of carnivores and omnivores increased towards the outer sector, at stations with coarse sediment fractions. Guanabara Bay can be divided into three main zones with respect to environmental conditions and polychaete diversity and biomass patterns: A) High polychaete diversity, hydrodynamically exposed areas composed of sandy, oxidized or moderately reduced sediments with normoxic conditions in the water column. B) Low diversity and high biomass of deposit and suspension-feeding polychaete species in the middle part of the bay near continental inflows, comprising stations sharing similar proportions of silt, clay and fine sands. C) Azoic area or an impoverished polychaete community in hydrodynamically low-energy areas of silt and clay with extremely reduced sediments, high total organic matter content and hypoxic conditions in the water column, located essentially from the mid-bay towards the north sector. High total organic matter content and hypoxic conditions combined with slow water renewal in the inner bay seemed to play a key role in the polychaete diversity and biomass. Sedimentation processes and organic load coming from untreated sewage into the bay may have negatively affected the survivorship of the fauna.
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INTRODUCTION: Spotted fevers are emerging zoonoses caused by Rickettsia species in the spotted fever group (SFG). Rickettsia rickettsii is the main etiologic agent of Brazilian spotted fever (BSF) and it is transmitted by Amblyomma spp. ticks. METHODS: The study aimed to investigate SFG rickettsiae in the Arthur Thomas Municipal Park in Londrina, PR, by collecting free-living ticks and ticks from capybaras and blood samples from personnel working in these areas. Samples from A. dubitatum and A. cajennense were submitted for PCR in pools to analyze the Rickettsia spp. gltA (citrate synthase gene). RESULTS: All the pools analyzed were negative. Human sera were tested by indirect immunofluorescence assay with R. rickettsii and R. parkeri as antigens. Among the 34 sera analyzed, seven (20.6%) were reactive for R. rickettsii: four of these had endpoint titers equal to 64, 2 titers were 128 and 1 titer was 256. None of the samples were reactive for R. parkeri. An epidemiological questionnaire was applied to the park staff, but no statistically significant associations were identified. CONCLUSIONS: The serological studies suggest the presence of Rickettsiae related to SFG that could be infecting the human population studied; however, analysis of the ticks collected was unable to determine which species may be involved in transmission to humans.
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This study aimed to investigate the occurrence of coronaviruses (CoVs) in captive birds placed inside a zoological park in Brazil. The role of captive birds in the epidemiology of CoVs in the tropics is poorly understood. A total of 25 (n = 25) different species were tested for viral RNA using individual fecal samples collected from healthy birds. Reverse transcription-polymerase chain reaction targeting the 30 untranslated region was used to detect CoV RNA, and positive samples were submitted for sequence analysis. The phylogenetic search revealed nine mutations in the black shouldered peafowl (Pavus cristatus) CoV sequence, which clustered separately from samples previously described in England. This is the first report on the detection of the CoV genome in captive birds in Brazil.
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Wild-caught larvae, attributed to the lobster shrimp Arius serratus, consisting of two zoeal stages and a decapodid (megalopa), are described in detail. Parentage of larvae was ascertained based on geographic distribution of axiideans and gebiideans (= former thalassinideans) within the study area and close morphological resemblance to other congeneric larval stages. Larvae of A. serratus represent the first described 'thalassinidean' larvae from Canadian Atlantic waters and the first for Axiidae within the northwest Atlantic. Among axiidean larvae, those of A. serratus most closely resemble larvae of A. stirhynchus from the eastern Atlantic. Distinct features include the spination of the pleon that set A. serratus zoeae apart from those of most other 'thalassinideans' but that, in combination with a telson very similar to Homarus americanus, contributes to the general resemblance of A. serratus larvae to those of the American lobster. The primary distinction between these taxa is the presence of a chela on the third pereiopod in the latter that is not present in the former. In view of these appendages being prone to loss or damage, other characters that separate these taxa are listed and discussed. Given the uncertain status of some taxa within Axiidae and limited detailed information of larvae with certain parentage, difficulties in delineating the family based on larvae persist, as they do for cladistic analyses using adult morphology and molecular approaches.
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Lignin phenols were measured in the sediments of Sepitiba Bay, Rio de Janeiro, Brazil and in bedload sediments and suspended sediments of the four major fluvial inputs to the bay: Sao Francisco and Guandu Channels and the Guarda and Cacao Rivers. Fluvial suspended lignin yields (Sigma 8 3.5-14.6 mgC 10 g dw(-1)) vary little between the wet and dry seasons and are poorly correlated with fluvial chlorophyll concentrations (0.8-50.2 mu gC L(-1)). Despite current land use practices that favor grassland agriculture or industrial uses, fluvial lignin compositions are dominated by a degraded leaf-sourced material. The exception is the Guarda River, which has a slight influence from grasses. The Lignin Phenol Vegetation Index, coupled with acid/aldehyde and 3.5 Db/V ratios, indicate that degraded leaf-derived phenols are also the primary preserved lignin component in the bay. The presence of fringe Typha sp. and Spartina sp. grass beds surrounding portions of the Bay are not reflected in the lignin signature. Instead, lignin entering the bay appears to reflect the erosion of soils containing a degraded signature from the former Atlantic rain forest that once dominated the watershed, instead of containing a significant signature derived from current agricultural uses. A three-component mixing model using the LPVI, atomic N:C ratios, and stable carbon isotopes (which range between -26.8 and -21.8 parts per thousand) supports the hypothesis that fluvial inputs to the bay are dominated by planktonic matter (78% of the input), with lignin dominated by leaf (14% of the input) over grass (6%). Sediments are composed of a roughly 50-50 mixture of autochthonous material and terrigenous material, with lignin being primarily sourced from leaf. (C) 2010 Elsevier Ltd. All rights reserved.
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The biogeochemical processes affecting the transport and cycling of terrestrial organic carbon in coastal and transition areas are still not fully understood One means of distinguishing between the sources of organic materials contributing to particulate organic matter (POM) in Babitonga Bay waters and sediments is by the direct measurement of delta(13)C of dissolved inorganic carbon (DIC) and delta(13)C and delta(15)N in the organic constituents. An isotopic survey was taken from samples collected in the Bay in late spring of 2004. The results indicate that the delta(13)C and delta(15)N compositions of OM varied from -21.7 parts per thousand to -26 2 parts per thousand. and from + 9 2 parts per thousand. to -0 1 parts per thousand, respectively. delta(13)C from DIC ranges from +0.04 parts per thousand to -12.7 parts per thousand The difference in the isotope compositions enables the determination of three distinct end-members terrestrial, marine and urban Moreover, the evaluation of source contribution to the particulate organic matter (POM) in the Bay, enables assessment of the anthropogenic impact. Comparing the depleted values of delta(13)C(DIC) and delta(13)C(POC) it is possible to further understand the carbon dynamic within Babitonga Bay (C) 2010 Elsevier BV All rights reserved
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The Brazilian Atlantic Rainforest is internationally recognised as one of the most biodiverse and threatened tropical forests in the world [Myers, N., Mittermeier, R.A., Mittermeier, C.G., da Fonseca, G.A.B., Kent, J., 2000. Biodiversity hotspots for conservation priorities. Nature 403, 853-858]. The Seasonal Semi-Deciduous Forest is among the most fragmented and threatened biomes of the Atlantic Rainforest Domain. The largest remnant of this biome (35,000 ha) is protected by the Morro do Diabo State Park (MDSP), situated in the area known as the Pontal do Paranapanema, in Sao Paulo State, Brazil. Despite its environmental importance, the park is under political, economic and demographic pressure. The main aim of our research was to estimate the population`s willingness to pay (WTP) for the conservation of MDSP and for the Atlantic Rainforest`s remnants in Sao Paulo State as a whole, by means of the contingent valuation method (CVM). The results featured a high incidence of null WTP and of protest votes. Nevertheless, the population is willing to pay US$ 2,113,548.00/year (R$ 7,080,385.00/year) for the conservation of the MDSP (use and existence values), or US$ 60.39 ha/year (R$ 202.30/ha/year). The results indicate that the preservation value is strongly associated to the population`s ability to pay, increasing with income levels. Qualitative research questions showed that the population considers protected areas to be very important. Still, the valuation of MDSP revealed a gap between the government budget allotted to the park and the value assigned to the area by the public. (C) 2007 Elsevier B.V. All rights reserved.
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The greenhouse effect and resulting increase in the Earth`s temperature may accelerate the mean sea-level rise. The natural response of bays and estuaries to this rise, such as this case study of Santos Bay (Brazil), will include change in shoreline position, land flooding and wetlands impacts. The main impacts of this scenario were studied in a physical model built in the Coastal and Harbour Division of Hydraulic Laboratory, University of Sao Paulo, and the main conclusions are presented in this paper. The model reproduces near 1,000 km(2) of the study area, including Santos, Sao Vicente, Praia Grande, Cubatao, Guaruja and Bertioga cities.