Navegando por Assunto "Ecossistema aquático"

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Acesso aberto (Open Access)
Abordagem multicriterial e indicadores ecológicos e econômicos utilizados na identificação de áreas prioritárias para a conservação da ictiofauna no Estuário Amazônico, Brasil
(Universidade Federal do Pará, 2012) MOURÃO, Keila Renata Moreira; FRÉDOU, Flávia Lucena; http://lattes.cnpq.br/4779271407117528
This study was divided into three steps: (1) description of spatial and temporal distribution of fish fauna in the area of transition from marine and freshwater environments (Chapter 1), (b) use of descriptors of community as a way to determine the community structure and use of the habitat for fish fauna (Chapter 2) and (3) use of community descriptors studied in Chapters 1 and 2, as a criteria to development indicators (integrated in GIS environment) to define priority areas and scenarios for the conservation of the fish fauna (Chapter 3). The collections of the fish fauna in the main channel and tidal creek occurred from 2004 to 2011 during the dry period (July- December) and rainy period (January-June), using gill net, trawl and block net as fishing gears, and in three important areas of the Amazon estuary: the bays of Guajará and Marajó and Guamá River. A total of 41,516 specimens of 136 species, 38 families and 12 orders were captured. The spatial and temporal distribution of fish fauna in the area of transition from mesohaline and freshwater environments showed that species richness increases from the Guamá River towards the Marajó Bay, along with the increasing salinity. In relation to trophic functional groups, piscivores (PV) and zoobentívoros (ZB) were dominant in all areas. The community descriptors obtained in the main channel, showed the highest values of biomass and relative abundance in number in Marajó Bay. In relation to the tidal channel, the abundance of biomass was greater in Guajará Bay. The main channel is used for breeding and nursery, and 90% of the individuals were immature. The indicators of diversity of the environment (DA), habitat use (UH), relative abundance (CPUE), environmental health (SA) and relation to fisheries (PR), showed conservation priorities considered medium and high, along the area study. This trend was also observed considering the ecological and economic scenarios, that showed medium-high and high-very high priority for conservation of the fish fauna in the northern portion Marajó Bay in the dry period, respectively. The methodologies used determined the ecological importance of the study area, emphasizing the heterogeneity between them and therefore cannot be considered as a single environment. The multicriteral approach adopted has no precedent for the Amazon estuary. This methodology proved to be effective in providing, through the different scenarios, a range of options that allows the decision maker to explore the issue as best as possible or use it as part of a process of decision making.
Acesso aberto (Open Access)
Assembleias de ciclídeos na área focal da Reserva de Desenvolvimento Sustentável Mamirauá, médio Rio Solimões, Amazonas, Brasil
(Universidade Federal do Pará, 2010-03-19) PEREIRA, Ludmilla Costa Ferreira; CAMARGO-ZORRO, Mauricio; http://lattes.cnpq.br/5423657235023988
This study aims to know the fish diversity of the family Cichlidae in different habitats (lakes, ressacas and river banks) and habitats (floating macrophytes, branches and beaches) on Sustainable Development Reserve Mamiraua (RDSM), medium Solimoes River, Amazonas. Samples were collected in two periods: 1) Three months sampled in March, July and December 2003 in 21 environments; 2) from September 2003 to August 2004 in five lakes with presence of the floating meadows Eichornia crassipes and Paspalum repens. Were used gillnets, hand nets and seine nets. Were collected 6397 fishes and 350 kilograms, represented in 28 species and 16 genera. Cichlids represented approximately 35% of the total number of fish collected. The composition of the catch was dominated by juvenile forms or small fishes. Mesonauta insignis and Cichlassoma amazonarum dominate in abundance and weight along the study. Species richness was larger in the period I (28 species), while during the period II were recorded 19 species. Nine species were absent in lakes with floating meadows. The study showed that the cichlids moving between environments and habitats of the Reserve in search of better conditions for their survival.
Acesso aberto (Open Access)
Caracterização biogeoquímica de ecossistemas amazônicos: rios e lagos selecionados das microrregiões Bragantina, do Salgado e Guajarina - PA
(Universidade Federal do Pará, 1999) MENEZES, Lúcia Beckmann de Castro; LIMA, Waterloo Napoleão de; http://lattes.cnpq.br/1229104235556506
It was compared physical, chemical, physical-chemical and hydrobiological environmental parameters of waters and of aquatic humic material, in three kind of places seemingly identified, because these parameters are excellent indicators of biogeochemical and ecophysiological characteristics of aquatic ecosystems, in the attempt of characterizing the influence of the biogeochemical factors of pollution, the anthropogenic influence and the studied ecosystems productivity. It was collected samples in the course of the Guama river, in Ourem – Bragantina zone (high course), in Bujaru (medium course) and in Belem - Guajarina zone (close to estuary), as well as in two lakes of coastal plain located in the island of Atalaia (Salinopolis), and still in the Arapepo river (municipal district of Salinopolis – Salgado zone), this one under strong influence of the waters of the Atlantic ocean, in the months of December of 1996 (drought period), May of 1997 (rainy period) and October of 1997 (drought period). The methods used in the characterization involved physical-chemical analysis and chemical analysis for the determination of the chemical composition in relation to the dominant ions and the indicators of the presence and of the decomposition of the organic matter (humic material) and hydrobiological analysis, for chlorophyll evaluation, in natural waters, submitted or not to an anthropic action. It was utilized the ultraviolet and visible spectrophotometry and in the infra-red spectroscopy to the characterization of the natural organic matter, where the humic acid and fulvic acid prevail. The spectra in the ultraviolet-visible were also used for the identification of the chlorophyll. The analytic results have showed a clear difference among the studied ecosystems, suggesting an influence of an anthropic action in the Guama river, which characterizes the lakes in Salinopolis as an ambient with high amount of organic matter (humic substances) and the Arapepo river presenting results very differents due to the oceanic influence and to the occurrence of mangroves in its margins, being the only ecosystem where the occurrence of photosynthetics pigments were perceived (chlorophyll). The calculation of the ionic relation indicated the presence of marine intrusion in the environments of the lakes I and II, Arapepo river and Guama river (Belem). The seasonal was reflected intensively in the three studied ambients, through parameters as color, turbidity, specific conductivity, chloride, sulfate, organic matter (consumed oxygen), iron and the larger cations (calcium, magnesium, sodium and potassium), notedly in the physiografic area of the Salgado zone. The relation carbon/nitrogen observed for the humic substances suggests that the humic material of the lakes has an older formation than the rivers. The rate E4/E6 obtained through the spectra in the ultraviolet-visible indicates that the humic and fulvic acids present in the samples have a high aromaticity. The interpretation of the spectra of absorption in the area of the infra-red, has permitted to verify that there are present the most characteristic bands, indicating the presence of groups C-H, C=O and COOH and also of aromatic skeleton and suggesting the formation of humic substances - metal complex, what is in conformity with the analytic results obtained for metals in the humic material. The amount of metals (iron, manganese, copper, chromium and zinc) presents in the humic material were always larger in the samples of the Guama river (Belem), what suggests enrichment due to anthropogenic influence.
Acesso aberto (Open Access)
Composição, distribuição, utilização de ambientes e variação sazonal na densidade de quelônios aquáticos do Lago Verde, Alter do Chão, Santarém, Pará, Brasil
(Universidade Federal do Pará, 2010) LEITE, Rachel Ullmann; PEZZUTI, Juarez Carlos Brito; http://lattes.cnpq.br/3852277891994862
Acesso aberto (Open Access)
Contaminação invisível - uma proposta para divulgação e visibilidade e visibilidade aos microplásticos
(Universidade Federal do Pará, 2022-08-10) CARVALHO, Renan Almeida de; MARTINELLI FILHO, José Eduardo; http://lattes.cnpq.br/2080628833884538
Solutions that are microplastics derived from commercial microplastics, or even by industry, by some plastic fragments caused by higher tempering and plastic, chemical and biological reduction. As well as their material, microplastics also have distinct physical properties such as density, for example, which can primarily determine the dynamics of the position of these particles in the environment. From this, it is possible to find that we can find all microplastic particles of water in an ambient column. Therefore, microplastics can contaminate both the biota present in the water column and in the bottom of ecosystems. In order to contribute to the environmental sciences for teaching the water column for the microplastic work environment and for the project as the auxiliary product for water in water environments, water packs for the environment of low density polypropylene (PP) and polyethylene terephthalate (PET) with high relative density. In order to validate the application of the product as a didactic tool, the study was applied to two classes of the 7th year of elementary school. The class was an applied theoretical class and the second class was on the MP theme, and the second class was an applied class, the model and the subject. After analyzing the question answered by the classes, it was observed that when the model was presented in the class, there was a significant difference in the proportion of correct answers for six from the eight questions.This indicated a positive relationship between the use of models as a tool to aid in the teaching of Environmental Sciences.
Acesso aberto (Open Access)
Cytogenetic damage related to low levels of methyl mercury contamination in the Brazilian Amazon
(2000-12) AMORIM, Marúcia Irena Medeiros de; MERGLER, Donna; BAHIA, Marcelo de Oliveira; DUBEAU, Hélène; MIRANDA, Daniela; LEBEL, Jean; BURBANO, Rommel Mario Rodriguéz; LUCOTTE, Marc Michel
The mercury rejected in the water system, from mining operations and lixiviation of soils after deforestation, is considered to be the main contributors to the contamination of the ecosystem in the Amazon Basin. The objectives of the present study were to examine cytogenetic functions in peripheral lymphocytes within a population living on the banks of the Tapajós River with respect to methylmercury (MeHg) contamination, using hair mercury as a biological indicator of exposure. Our investigation shows a clear relation between methylmercury contamination and cytogenetic damage in lymphocytes at levels well below 50 micrograms/gram, the level at which initial clinical signs and symptoms of mercury poisoning occur. The first apparent biological effect with increasing MeHg hair level was the impairment of lymphocyte proliferation measured as mitotic index (MI). The relation between mercury concentration in hair and MI suggests that this parameter, an indicator of changes in lymphocytes and their ability to respond to culture conditions, may be an early marker of cytotoxicity and genotoxicity in humans and should be taken into account in the preliminary evaluation of the risks to populations exposed in vivo. This is the first report showing clear cytotoxic effects of long-term exposure to MeHg. Although the results strongly suggest that, under the conditions examined here, MeHg is both a spindle poison and a clastogen, the biological significance of these observations are as yet unknown. A long-term follow-up of these subjects should be undertaken.
Acesso aberto (Open Access)
Determinantes da estrutura de comunidades de insetos aquáticos em riachos na Amazônia: o papel do habitat e da escala especial
(Universidade Federal do Pará, 2017-01-30) BATISTA, Gilberto Nicacio; HAMADA, Neusa; http://lattes.cnpq.br/1512994126787334; JUEN, Leandro; http://lattes.cnpq.br/1369357248133029
Aquatic ecosystems are highly complex environments, mainly due to interactions between their abiotic and biotic components; they are dependent on variation in physical structure and limnological characteristics, which in general, are factors that specifically act on different spatial and temporal scales. Therefore, considering this complexity in structuring stream habitats, particularly in Amazonian lotic ecosystems, this doctoral thesis aims to evaluate which are the determining factors to structure aquatic insect communities and their distribution according to environmental variation and geographical distances. To meet this goal the thesis is divided into four chapters. In the first, a systematic revision was carried out with a global assessment about the use of insects (Chironomidae: Diptera) in monitoring aquatic ecosystems and their responses as bioindicators. We found that the main issues presented in the studies were related to anthropogenic impacts on aquatic ecosystems and the taxonomic difficulties on the use of species identification to biomonitoring. The second shows analysis of distribution patterns and diversity of Chironomidae communities, under predictions of Metacommunity models, to evaluate the relations of the assemblages with the spatial scale and the environment. The main results showed that the assemblages were mainly affected by components of the physical habitat structure and partly the communities were limited by dispersal among the streams when considered at large scale in the region studied. The third showed analysis of functional composition on the communities of aquatic insects (Coleoptera, Diptera, Ephemeroptera, Hemiptera, Lepidoptera, Megaloptera, Odonata, Plecoptera, Trichoptera) and their responses to variation in habitat structure considered under the assumptions of the Habitat Templet. Overall, we found relationships between the distribution of morphological and functional traits with the physical habitat variables. The fourth chapter evaluates the effect of spatial distance on the community similarity of Ephemeroptera, Trichoptera, Plecoptera communities in two regions of Eastern Amazon. In this final chapter, we find differences in the composition of communities expressed as species replacement because of the geographical distance and local environmental characteristics of each region. Finally, the studies developed in this thesis summarized how the structure of the habitat of streams can affect the aquatic insect communities and variation in the riparian structure and physical habitat, can cause variation in taxonomical composition and functional attributes. In summary, from these findings, we conclude that the physical habitat variables are determining factors in structuring aquatic insect communities. In addition, it is highlighted the importance of local factors (riparian vegetation structure/composition of substrates/limnological characteristics) as explanatory variables for taxonomical and functional composition. In addition, the regional factors (geographical distance / dispersal limitation) are essential components to affect similarity and structure of the communities.
Acesso aberto (Open Access)
Diversidade e abundância de algas epilíticas no setor do médio Rio Xingu-PA
(Universidade Federal do Pará, 2010-08-31) BASTOS, Alessandra dos Santos Matni; CAMARGO-ZORRO, Mauricio; http://lattes.cnpq.br/5423657235023988
The periphyton is defined as a complex community of microorganisms (fungi, algae, bacteria, animals), which along with organic and inorganic particles is loosely or firmly adhered to a substrate submerged. Epilithic algae (bedrock) are organims found in environments of rivers and rapids, and other ecosystems. This paper aims to list the diversity of epilithic algae, estimate their relative abundance and frequency of occurrence during an annual cycle. In the main channel of the river Xingu was selected environment rapids of Boa Esperança and localities Arroz Cru. The epilíton was removed, properly identified and preserved in Transeau solution and subsequently analyzed in the laboratory. Were listed 132 species belonging to 78 genera. The total richness observed for Boa Esperança and Arroz Cru, in the months studied were 108 and 101 species respectively. Among all classes, Bacillariophyceae expressed greater contribution in both localities in terms of richness and abundance. The epilithic specie more abundant was Aulacoseira granulata (Ehrenberg) Simonsen (Bacillariophyceae), in the locations studied. In november/2006 and january/2007 (flood) occurred at higher densities mean: 133 and 124 ind.cm-2 in the riverine environment Boa Esperança. In the Arroz Cru was 107 and 90 ind.cm-2. The lowest mean density occurred in march/2007 (filled) with 26 ind.cm-2 in the riverine environment and Boa Esperança in august 2006 (flood) with 15 ind.cm-2 in Arroz Cru. The diversity of epilíton varied among seasons. The precipitation, wind, turbidity and nutrients, possibly influence the variations of abundance, richness and density.
Acesso aberto (Open Access)
Diversidade genética de isolados ambientais de Vibrio cholerae da Amazônia brasileira
(Universidade Federal do Pará, 2009-09-30) SÁ, Lena Líllian Canto de; VICENTE, Ana Carolina Paulo; http://lattes.cnpq.br/9393006603341915
Vibrio cholerae, the etiologic agent of cholera, is an autochtonus bacterium of aquatic environment in temperate and tropical regions of the world. Cholera is endemic and epidemic in many countries in Africa, Asia and Central and South America. In this study our goal was to detemine the genetic diversity of V.cholerae environmental isolates from aquatic ecosystems in the Amazon region of Brazil. A total of 148 environmental strains of V.cholerae non-O1 and non-O139 (NAG) and O1 serogroups, isolated from the Amazon region since 1977 to 2007, were characterized and compared with clinical strains of V.cholerae O1 from sixty and seventh cholera pandemic. PFGE (pulsed-field gel electrophoresis) was performed to determine the clonal relationships between V.cholerae non-O1, O1 environmental and clinical strains. The presence of virulence genes (hlyA/hem, hlyB, hlyC, rtxA, rtxC, tcp, ctx, zot, ace, stn/sto) and class 1, 2 and 3 integrons (intI 1, 2 e 3) was analyzed by polymerase chain reaction. Whole genome macrorestriction analysis revealed that the environmental V.cholerae NAGs were more diverse than the environmental O1 strains, both groups segregate in distinct clusters and most of environmental O1 strains show a clonal relationship with seventh cholera pandemic strains. The distribution of virulence genes in NAGs strains is largely different from that of O1 strains which, in general, were positive for all virulence genes analyzed excepting for stn/sto and class 1, 2 and 3 integrons. Some O1 environmental strains, belonging to the seventh pandemic lineage, went through an extensive gene loss. Distinct NAGs strains were stn/sto+ and intI 1+. Two alleles of aadA were found: aadA2 and aadA7. Interestingly, V.cholerae O1 environmental strains belonging to the pandemic lineage were only isolated during the period of cholera epidemic in the Amazon region of Brazil (1991-1996).
Acesso aberto (Open Access)
Diversidade, distribuição e estrutura da comunidade de peixes na Estação Científica Ferreira Pena: Amazônia Oriental
(Universidade Federal do Pará, 2001-11-20) MONTAG, Luciano Fogaça de Assis; BARTHEM, Ronaldo Borges; http://lattes.cnpq.br/4192105831997326
The conservation of the biodiversity in aquatic ecosystems is one of the most important and difficult challenges in the current world. According to available information, the biodiversity of aquatic ecosystems is poorly understood in comparison with tropical terrestrial ecosystems. Thus, systematic and taxonomic analyses, the understanding of phylogenetic, biogeographical and ecological relationships represent items that need to be investigated. The first question addressed is the characterization of the ecosystem. We observed that the environmental features, mainly wideness and depth, ranges spatially along the rivers and possess the inferior zone with strong characteristics of river—lake transitional areas. The following question was to estimates fishes richness of in the Ferreira Penna Scientific Station. In order to answer this question, we used protocol techniques and obtained 130 species, of these 39 were separated by morphospecies. This fact indicates that approximately 30% of the fauna might be new or there is no available bibliography for identification. The species collected in the inventory are considered to represent a reasonable set of the ichythyofauna of the region. Lastly, we aimed to characterize fish communities and expose the patterns of distribution of species concerning the investigated habitats. As a result, we observed that the com position of species in the communities followed the substitution and addition pattern. The greatest diversity of species was observed for the final zones of the rivers. The increase in the water volume and area in some habitats of the rivers makes possible their exploitation by a larger number of individuals or new species.
Acesso aberto (Open Access)
Efeito da alteração do hábitat sobre assembleias de peixes em igarapés afogados da Amazônia oriental
(Universidade Federal do Pará, 2014-02-26) SOUSA, Híngara Leão; FERREIRA, Cristiane de Paula; http://lattes.cnpq.br/7804816854015308; MONTAG, Luciano Fogaça de Assis; http://lattes.cnpq.br/4936237097107099
The natural aquatic ecosystems are complex systems that are exposed to a variety of disturbances. In the Amazon region, for instance, land use and occupation have altered the physical structure of aquatic environments, especially regarding the small streams, influencing their communit structure and composition. This has led to research development and evaluation programs to see how the changes that are occurring in these environments affect biotic communities, through habitat characteristics that are more sensitive to disturbance. Thus, this study aimed to describe and measure physical attributes of drowned out streams and evaluate how fish assemblages respond to different levels of streams physical integrity. Our hypothesis is that structurally intact environments endure a more diverse ichthyofauna than altered environments, since their decreased environmental complexity limits the potential ecosystem, because they presented a decrease in environmental complexity. The study was conducted in 34 streams, 17 located within the territory of Caxiuanã National Forest, and 17 in its surroundings, located close to Portel and Melgaço cities (PA). The process of urbanization is expanding in the region, reaching areas of forests and streams that are still preserved. There is also an intense logging, because the area is included in the main timber pole of the estuary in the state of Pará. The physical habitat was evaluated according to a standardized protocol of stream environmental assessment. The samplings were conducted with hand nets passed along 150 meter long reaches during six hours (divided among segments and collectors). Although a set of metrics which responded to the local impact gradient has been detected these were not sufficient to reduce or increase the number of species across different levels of preservation, maintaining substantially constant the wealth and abundance for all three groups (altered, intermediate and preserved). However, the difference was significant for the composition, with eleven exclusive exclusive species of altered habitats and eight preserved environments. The degradation of the physical environment, even at smaller scales favors the occurrence and abundance of most tolerant species and phenotypic plasticity, in addition to the population increase of opportunistic species. Different effects can be exerted on the groups of species that make up a community, since they have different biological and ecological attributes that include your answers to the same ecological variables. Therefore, the possible deconstruction of community groups of species (taxonomic, functional, etc.) may show different responses to the changes of habitat, being a promising strategy for linking environmental standards of richness characteristics displayed by these communities. Assessment of biotic integrity is also an alternative to identify effects of habitat alteration on species, especially considering the region’s peculiarity and the lack of information about the local ichthyofauna.
Acesso aberto (Open Access)
Efeito de características ambientais no uso dos canais-de-maré por três espécies de peixes bentófagos durante o período transição-seca no estuário de Curuçá (Pará-Brasil)
(Universidade Federal do Pará, 2009-08-10) ALMEIDA, José Bruno Araújo de; GIARRIZZO, Tommaso; http://lattes.cnpq.br/5889416127858884; ISAAC, Victoria Judith; http://lattes.cnpq.br/3696530797888724
The Curuçá estuary is part of a Conservation Unit (RESEX Great Mother of Curuçá) since 2002 and has as main water courses the Curuçá River and Muriá bore. This study aimed to analyze the effect of environmental characteristics in the use of the creek on the benthophagous species Colomesus psittacus, Sciades herzbergii and Genyatremus luteus. The analysis involved the relationship of environmental data (salinity, submergence area and tree cover) and biotic data from the three species studied (density, biomass, feeding intensity and distribution of total length). The first expedition took place in July 2008 to collect the fish fauna and the second in October 2008 to conduct the tree inventory, and each campaign lasted for three days. For all the estuary of Curuçá, more precisely, along the Curuçá River and Muriá bore were allotted a total of six study sites, where within each site were sampled two creeks, making a total of twelve creeks sampled. The species C. psittacus, S. herzbergii and G. luteus were among the five most abundant and occurred in all sites, except for S. herzbergii, which was captured only in five of the six sites. The three species showed, among sites, highly significant differences for changes in their average density, biomass, index of fullness and length, except for G. luteus which did not show statistical differences in their average total length. All variations of the average environmental characteristics related to tree cover (density, height and diameter), as well as, the area of flood creek showed significant differences between sites. This study has showed: the influence of salinity gradient in the distribution of species within the estuary; spatial relations between the flooded area and availability of food resources, where the creek with larger flooded area were more conducive to forage fish fauna benthophagous; likely, there is a better yield when feeding species benthophagous occurs in creek surrounded by vegetation developed.
Acesso aberto (Open Access)
Efeitos do espaço e do ambiente sobre assembleias de peixes de igarapés da Amazônia oriental
(Universidade Federal do Pará, 2012) BENONE, Naraiana Loureiro; MONTAG, Luciano Fogaça de Assis; http://lattes.cnpq.br/4936237097107099
The amazon streams have harsh environmental characteristics for several fish species due to their oligotrophic conditions. In spite of that, these watercourses possess a rich and diversified ichthyofauna, resulting from the various microhabitats found in streams. In ria lake systems, the rivers and streams suffer a natural impoundment, which provokes a lowering on current velocity values. This could homogenize the environment, since current velocity affects many of the streams features. Thereby, distance between streams could have its importance emphasized as a structural factor of stream fish assemblages. This study aimed to analyze the influence of space and environment on the structure of fish assemblages in drowned streams of Caxiuanã, in Eastern Amazon. The fishes were caught during the period of drought of 2010, including 34 transects of drowned streams. Eight abiotic factors were measured to test the effect of the environment. To analyze the effect of the space, space filters were calculated based on the geographical coordinates, as well as the distance among the streams following the watercourse. The analyses showed that the environment was the only factor to influence the beta diversity, refuting the hypothesis of the space as a structuring factor and reinforcing the paper of the ecological niche in the distribution of species. Nevertheless, the abiotic factors explained a low percentage of the variation in the fish composition, what shows that other variables can affect these assemblages.
Acesso aberto (Open Access)
Eficiência de diferentes abordagens metodológicas e caracterização das associações macrobentônicas estuarinas da zona costeira amazônica
(Universidade Federal do Pará, 2009-06-10) MONTEIRO, Viviane Ferreira; ROSA FILHO, José Souto; http://lattes.cnpq.br/3223362071251898
The estuarine macrobenthic communities from Amazonian coastal regions were characterized using different mesh sizes and sampling depths. The samplings were performed in Algodoal island and peninsula of Ajuruteua (PA), during rainy and dry seasons (June and December 2007, respectively) at the following habitats: mangrove edge, mangrove, sandy and muddy-sandy paths. At each habitat eight biological samples were collected using a cylindrical corer with 0.0079 m², as well as samples for sediment analysis (texture, moisture and organic matter concentrations) and chlorophyll a and pheopigments concentrations. Each biological sample was devided into three strata (0-5, 5-10 and 10-20 cm) and they were sieved on mesh screen sizes of 1.0, 0.5, 0.3 and 0.25 mm. Univariate (ANOVA) and multivariate (MDS, ANOSIM, SIMPER and BIOENV) techniques were used for data analysis. Macrofaunal composition consisted of 68 taxa with dominance of Annelida (Tubificidae and Capitellidae). Meshes of 0.3 and 0.25 mm were the most efficient in terms of retention of organisms and species, while the mesh of 1.0 mm lost significant quantities of organisms, especially Tubificidae. The samples collected at 10 and 20 cm depth did not differ significantly regarding to the number of taxa and organisms. Significant spatial variations were observed on the macrofaunal structure between habitats in both locations and sampling moments, with higher density and richness in muddy paths (mangrove edge and mangrove). The amount of clay, organic matter and moisture concentrations of the sediment were the most correlated environmental variables with the fauna. It could be concluded that: 1. the benthic macrofauna in Algodoal island and peninsula of Ajuruteua was composed by few taxa, and those were typically estuarine and of small dimensions, dominated by Annelida; 2. for characterization of benthic macrofauna is necessary to take samples at 10 cm depth and sieve them on mesh of 0.3 mm size; 3. Muddy-sandy habitats presented normally highest densities and richness; 4. only in Algodoal island was observed temporal variation in the structure of benthic macrofauna; 5. the amount of clay, pheopigments and moisture content in the sediment were the main factors responsible for macrofaunal structure.
Acesso aberto (Open Access)
Epidemiologia descritiva de Salmonella em ecossistemas aquáticos de diferentes áreas do Estado do Pará
(Universidade Federal do Pará, 2007-09-20) LOUREIRO, Edvaldo Carlos Brito; ISHAK, Ricardo; http://lattes.cnpq.br/5621101706909450
Surveillance of Salmonella serotypes in aquatic environments is an important procedure for the monitoring of human and animal infections. The analysis of 694 samples of water collected from river, creek, bay, beaches, lake, well, nascent, provisioning water, stream, drainage and sewage distributed along 11 districts in the State of Pará, Brazil, yielded 212 (30,5%) contaminated samples with 91 serotypes and 2,115 strains of Salmonella. In Belém, 77 sorotypes were identified out of 1,300 isolates from freshwater and sewage; S. Saintpaul, S. Panama, S. Muenster, S. Hadar and S. Agona were the most frequent serotypes. In the National Forest of Caxiuanã, 69,4% of water samples were positive for Salmonella and 17 serotypes were identified, being S. Panama, S. Miami and S. Gaminara the most frequent ones. Antibiotic resistance was described in 64.8% of the Salmonella isolates from aquatic environments, with a special importance to streptomycin (97,1%) and tetracycline (10,8%). The presence of Salmonella and thermo-tolerant coliforms in superficial and underground water was frequently associated, but E.coli was not isolated in ten occasions. Rappaport-Vassiliadis enrichment broth was more efficient than Selenite Cystine for the isolation of Salmonella when kept at 42,5ºC. The serotypes isolated from sewage closely resembled the isolates originated from human fecal cultures during the same period. The results show the dissemination of Salmonella in aquatic environments in the State of Pará and the risk to the health of the human population.
Acesso aberto (Open Access)
Estrutura das assembléias de macroinvertebrados de substratos rochosos no litoral de Curuçá, nordeste do Pará, Brasil
(Universidade Federal do Pará, 2011-04-15) MORAIS, Gisele Cavalcante; LEE, James Tony; http://lattes.cnpq.br/1693070833836566
Acesso aberto (Open Access)
A ictiofauna no monitoramento da qualidade ambiental em um distrito industrial do estuário amazônico
(Universidade Federal do Pará, 2011) VIANA, Andréa Pontes; ROCHA, Rossineide Martins da; http://lattes.cnpq.br/4371300451793081; FRÉDOU, Flávia Lucena; http://lattes.cnpq.br/4779271407117528
The district of Vila do Conde, in the municipality of Barcarena, is a prominent industrial hub, constituting a risk factor for water quality. Given this, the present study focused on the environmental quality of the aquatic habitats adjacent to this site, using the fish community as a bioindicator and liver two species of fish as a biomarker histopathological. The collection of abiotic data (water samples) and fish specimens was organized in three distinct zones, representing different levels of impact. Zone 1 was located in the vicinity of the Vila do Conde cargo terminal, where the risk of contamination was highest. Zone 2 was in the Capim Island, located on the border between the municipalities of Bacarena and Abaetetuba, classified as a median risk area due to its relative proximity to the port. Zone 3 was in Onças Island, which was classified as minimum risk, due to its distance from the industrial district of Vila do Conde. Two different types of environment – the main river channel and marginal tidal creek were sampled in all three zones. Samples were collected every two months, covering the region’s principal climatic periods - rainy-dry transition (June 2009), dry season (September 2009), dry-rainy transition (January 2010), rainy season (April 2010), in one year collection. Data was collected using monofilament gillnets and block net. Aiming to evaluate the water quality considering different tools, this study was divided into three parts. In the the first part, the icthyofauna was used as an bioindicator of water quality (Chapter 1). In the second part, two species abundant with different feeding habits, Plagioscion squamosissimus and Lithodoras dorsalis, to assess the health of the environment through the use of liver as a biomarker histopathological (Chapter 2). Finally, all families of descriptors (chapters 1 and 2), were combined into biological integrity indexes in chapter 3. The analysis of the icthyofauna as an bioindicator showed differences in the composition between zones and environments (main channel and tidal creek), for the different groups of descriptors. Considering the 77 species captured, only 23 species were recorded in comparison with the less impacted areas. Also, large fish were least common in zone 1. In the present study, the smaller proportion of larger-sized fish recorded in the impacted areas may reflect an ecological response to anthropogenic disturbance. Biomarker analysis, carried out through the liver histopatologic study, was efficient to detect the influence of antropogenic factors in the heatlh of P. squamosissimus e L. dorsalis. The MAV (Mean Assessment Values), HAI (Histological Alteration Index) e o MDS (multidimensional scaling) analysis all indicated clear differences between the areas surveyed. The alterations were more severe (in some cases, irreversible) in zone 1, which was closest to the port and the industrial district. The principal alterations observed in the tissue of both species included an increase in the number of melanomacrophagous centers, fatty degeneration, inflammation, congestion, hepatitis, and focal necrosis. The hepatic alterations observed in the present study were generally more intense in the carnivorous P. squamosissimus, which feeds mainly on shrimp in the region of the study area. Though integrity indexes, all community information were combined into metrics. In the present study, considering the ABC curve, in the main channel and creek, the zones 1 and 2 were classified as moderately disturbed, which predicts an increase in the relative abundance of opportunistic species. The BHI (Estuarine biological health index), EFCI (Estuarine fish community índex), TFCI (Transitional fish classification índex) e EBI (Estuarine biotic integrity index) were considered to be excellent indicators of the ecological integrity of the different sectors of the study area, and were especially effective for the demonstration of the critical alterations of the fish community of zone 1. It was also possible to identify alterations to the environment of zone 2. The procedures adopted in the present study were nevertheless adequate for the detection of the alterations to the environment which have occurred in the vicinity of the town’s industrial district and cargo terminal and are able to be replicted in others estuarine areas. However, more reliable information on the bio-accumulation of heavy metals in these species will be necessary. This is especially important due to the prominence of both species in the diet of the local communities.
Acesso aberto (Open Access)
A influência do ambiente e do espaço em comunidades de peixes estuarinos da Zona Costeira Amazônica
(Universidade Federal do Pará, 2012) SANTOS, Bruno Ayres; MONTAG, Luciano Fogaça de Assis; http://lattes.cnpq.br/4936237097107099
One of the objectives of fish assemblage ecology is to identify and predict the structuring patterns of these assemblages in response to biotic and abiotic interactions that occurs within the ecosystem. Specifically at the Amazon Coastal Zone there is growing number of studies being made about the influences of the environment and geographic location structuring estuarine fish assemblages, however, these influences have been evaluated separately, leaving incomplete the understanding of the dynamics within these environments. Therefore, this study aimed to identify the space-seasonal structuring pattern the ichthyofauna at Salinópolis Bay linking assemblage descriptors of fish assemblages with environmental and spatial variables. The sampling period took place on the rain and dry seasons of 2011 within the Salinópolis Bay using traditional sampling methods (bottom fish nets). A total of 1,294 indivuals were captured, distributed in 67 species and 27 families. Species Cathorops spixii (n = 121) and Cathorops agassizii (n = 201) were the most abundant during the rainy season. During the dry season, species Cathorops agassizii (n = 118) and Genyatremus luteus (n = 72) were most abundant. Results shown that fish diversity between seasons are very similar. The environmental and geographic variables do not influence the structure of the fish assemblage, suggesting a random pattern of distribution for this assemblage, following the null model pattern.
Acesso aberto (Open Access)
Invasion of the Indo-Pacific blenny Omobranchus punctatus (Perciformes: Blenniidae) on the Atlantic Coast of Central and South America
(2011) LASSO-ALCALÁ, Oscar; NUNES, Jorge Luiz Silva; LASSO, Carlos; POSADA, Juan; ROBERTSON, Ross; PIORSKI, Nivaldo Magalhães; VAN TASSELL, James
We examined 308 specimens of the Indo-Pacific blenniid Omobranchus punctatus deposited in four museum collections, and analyzed data on their collection locations to assess its invasion on the Atlantic coast of Central and South America. This species occurs in shoreline estuarine and marine habitats in the Indo-West Pacific. Previous sampling and recent records in the Tropical West Atlantic from 1930 to 2004 produced 20 records for: Panamá, Colombia, Venezuela, Trinidad and Brazil. In this work, we provide data on 17 new records for the Gulfs of Venezuela and Paria in Venezuela, as well as four records for Maranhão and Pará states in NE Brazil. The temporal pattern of collections (1930 - 2009) and the proximity of most localities to ports and zones of ship traffic indicate that O. punctatus was initially introduced to the Atlantic by ships travelling from India to Trinidad. Within Brazil the introduction is linked to shipping connected to petroleum platforms. In Maranhão and Pará the introduction may have occurred as a result of fish sheltering in fouling on hulls of ships moving between ports around the mouth of the Amazon River. Alternatively, the spread of this species along of the American coast may reflect the expansion of the range of O. puntactus through larval dispersal in northward flowing currents. We recommend monitoring of this introduced species, and studies of its ecology in West Atlantic areas.
Acesso aberto (Open Access)
Uso da abordagem diversidade funcional na estrutura das comunidades de macroinvertebrados aquáticos
(Universidade Federal do Pará, 2016-02-29) ANDRADE, Ana Luiza; MONTAG, Luciano Fogaça de Assis; http://lattes.cnpq.br/4936237097107099; FERREIRA, André Luiz Netto; http://lattes.cnpq.br/1272360228203358
Aquatic macroinvertebrates are largely used to evaluate the health and functioning of lotic ecosystems. These organizations operate in maintenance of ecosystem processes and are responsible for nutrient cycling and energy flow. But understand the mechanisms that structure such communities is still a challenge to ecological studies, with that comes the need to study new approaches and metrics investigative In this context it was inserted the functional diversity whose approach is based on morphological, physiological or behavioral characteristics of the species that play a role in the community or ecosystem.. In this sense, we did a literature review to investigate the trends and global gaps of functional diversity of aquatic macroinvertebrates of lotic systems. Studies with this approach are relatively new to the group and showed a rapid growth over the years, but has been little used in neotropical regions. Among the investigated items found variations in basic concepts of functional approach between the articles, which can lead to erroneous interpretations. We also find that the functional responses of aquatic insects were more abundant among the macroinvertebrates and more frequently in studies evaluating the effect of environmental impacts anthropic. At last, we tested the applicability of the functional diversity approach. We evaluated the functional and taxonomic responses of the orders Ephemeroptera, Plecoptera and Trichoptera of streams inserted in areas of oil palm plantations comparing them to streams of forested areas of Eastern Amazon. We found that the abundance of EPT differ among communities, being higher in plantations, while the species richness was greater in the forest, with the loss of nine genera EPT in oil palm streams. Even with this biological loss, functional diversity did not differ between communities. However, when we analyze the characteristics of the environment, there were differences in pH, number of trunks and proximity to roads, and these, along with water temperature were able to select the attributes functional trophic habit and body size in the EPT community.