Navegando por Assunto "Rio Tocantins (Baixo)"

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Composição centesimal, colesterol e maturação ovariana do Acetes marinus Omori, 1975 coletado no Baixo Tocantins
(Universidade Federal do Pará, 2007-11-30) ASSUNÇÃO, Antônia do Socorro Américo de; LOURENÇO, Lúcia de Fátima Henriques; http://lattes.cnpq.br/7365554949786769; PAIVA, Rosildo Santos; http://lattes.cnpq.br/0510818763187669
The specie Acetes marinus Omori, 1975, have full use as food constituting themselves into a kind of nutritional importance to the regional population, however, it is few studied. To contribute to a better use of this resource were conducted monthly collections of A. marinus during the months of January 2006 to June 2007, in two beaches, near of the Cametá town in low Tocantins river. They were certain the composition centesimal (%) and the content of cholesterol (mg/100g) relating to environmental parameters: pH, temperature and material in suspension of the subsurface water. The characterization of ovarian development, were based on the macro-and microscopic changes. For these two beaches the annual average pH was 7.52 ± 0.71, the temperature was 26.57 ° C ± 1.26, and the material in suspension was 73mg / L ± 65.53. For the composition centesimal of A. marinus got itself: 87.1% ± 1.1- moisture; 9.8% ± 1.3-ash, 71% ± 1.8-protein, 5.4% ± 2.9-lipids; 13.7 % ± 2,6- carbohydrates; 387.6% ± 13.2 kcal - calorific value. The content of cholesterol was 374.87 mg/100g ± 207.08. Was revealed a large potential nutrition, especially protein, for this species, but it is rich in cholesterol. And for developing ovarian were described three stages of maturation, based on four different types of oocytes.
Acesso aberto (Open Access)
Filogeografia de três espécies de Passeiriformes (Suboscines) na região do Baixo Tocantins - Ilha do Marajó - Pará
(Universidade Federal do Pará, 2008) FACCIO, Maya Sonnenschein; ALEIXO, Alexandre Luis Padovan; http://lattes.cnpq.br/3661799396744570
The area of the lower Tocantins river - Marajó Island is an excellent place to carry out a study integrating geological and biological data to understand processes responsible for the diversification of species in the Amazon. Population genetics and phylogenetic analyses of populations of three selected bird species (Xiphorhynchus spixii and Glyphorynchus spirurus - Dendrocolaptidae and Willisornis poecilinotus - Thamnophilidae) were carried out employing the mitochondrial gene ND2, and related to the geological scenario proposed for the landscape evolution in the area. Estimates based on maximum likelihood and Bayesian inference where used to infer intraespecific phylogenies and haplotype networks, in addition to tests for deviation of neutrality R2, AMOVA, F ST e Nm, which were employed in population genetic analyses of the three selected species. Xiphorhynchus spixii showed no phylogeographic structure and high levels of gene flow among all populations analyzed. The phylogenetic trees recovered for G. spirurus populations presented one group of haplotypes endemic to the Marajó Island (IM) sister to a second group with the remaining haplotypes belonging to all three areas analyzed; these topologies imply an apparent secondary contact between isolated endemic populations of IM with those of the continent. The tree obtained for W. poecilinotus was similar to that of G. spirurus, indicating that the formation of IM might have affected in a similar way populations of those two species sharing similar dispersion abilities. On the other hand, the lack of phylogeographic structure detected for X.spixii might have been caused by a higher dispersal capacity, thus leading to a different response to the same set of vicariant events. Molecular clock estimates for the node separating haplotypes endemic to IM from those found in ali three areas were 747.000 years BP in G. spirurus and 798.000 years BP in W. poecilinotus thus older than the estimated separation of the IM from the continent (near 10.000 years BP) based on geological data.
Acesso aberto (Open Access)
Filogeografia em lagartos no baixo Tocantins, Ilha do Marajó e Sul do Amapá
(Universidade Federal do Pará, 2008) SOUZA, Ana Carla Barros de; GONÇALVES, Evonnildo Costa; http://lattes.cnpq.br/8652560763793265; ÁVILA-PIRES, Teresa Cristina Sauer de; http://lattes.cnpq.br/1339618330655263
Filogeographical studies have helped to clarify the spatial and temporal context of the diversification of organisms from Amazonian, which can be directly compared with specific geological scenarios. This study aims to contribute with the reconstitution of the recent history of low Tocantins/Marajó Island from a philogeographical analysis of Gonatodes humeralis and Kentropyx calcarata. The questions to be answered are whether there is a distinction among the population of the southern Amapá, Marajó Island, and each side of the Tocantins river, and how these populations interrelate one each other. In addition, this work also aims to assess the usefulness of the gene cytochrome oxidase I as a marker for studies of lizard populations. Data from 49 specimens of G. humeralis and 32 of K. calcarata from 14 localities in southern Amapá, low Tocantins, Marajó Island, and of an external population of the focal area of study, in the city of Itaituba, Pará, were analyzed. The molecular studies were based on mitochondrial gene cytochrome oxidase I. The levels of genetic variability were calculated: diversity of nucleotides (π) and diversity of haplotypes (h), the genetic differentiation through the analysis of molecular variance (AMOVA) and the estimates of Fst for pairs of populations and distribution of the differences between pairs of sequences. It was used a statistical test to detect possible R2 events of recent demographic expansion. The phylogenetic relations between populations were evaluated by the construction of non-rooted trees using the methods of maximum parsimony (MP) and maximum likelihood (MV). The results show that although the COI has been rarely used for this purpose, the observed variation in sequences of populations of G. humeralis and K. calcarata indicates that it is a useful marker for Phylogeographic analysis. The five populations of both species studied here, are genetically structured. This indicates a low or, more probably, inexistent gene flow among them. The observed Phylogeographic relations, although more certainly to G. humeralis than K. calcarata, indicates that significant changes have occurred in relatively recent times in the drainage system in the low Tocantins river and Marajo island. This is due strong indications, obtained in this study, that in recent past there was more movement, active or passive, of the species between regions of Marajo and west of the Tocantins river that would have been the most directly affected by these changes.
Acesso aberto (Open Access)
Marcadores imunológicos na exposição mercurial na Região Amazônica
(Universidade Federal do Pará, 2007) ALMEIDA, Sintia Silva de; CORVELO, Tereza Cristina de Oliveira; http://lattes.cnpq.br/7253864056606024
Immune dysfunctions can appear by combination between genetic susceptibility and environmental factors. There are evidences, in humans exposed to total mercury (Hgt), of alterations in immune response, by Hgt induced autoantibodies. This work investigated the occurrence of Hgt-induced autoimmunity (HgtIA) among human being exposed to Hgt in the Tapajós region (Barreiras, Brasília Legal, São Luís do Tapajós), as well as in the riverines from Tocantins region (Panacauera) without exposition to Hgt. The of hair and blood samples were collected from 236 individuals during June of 2004 to December of 2006, in which the total mercury in hair was determined by atomic absorption spectrophotometer, and in the serum, autoantibodies were analyzed by indirect immunofluorescence microscopy, using human epithelial cells (HEp-2) as substrate. The highest Hgtotal levels was found in São Luís do Tapajós (11.24 ± 2.23 μg/g), following for Brasília Legal (10.00 ± 0.99) and Barreiras (8.64 ± 1.13), and the lowest were found in Panacauera (2.98 ± 0.20). When considering the variable sex, association with the levels of Hgtotal in hair was observed only in Brasília Legal. Regarding mercury exposure, the autoantibodies in serum was more frequent in riverine of the Tapajós (79.65%) than in the control group (31.25%). Most of the autoantibodies patterns identified by immunofluorescence were: mixed (50.96%), nuclear (31.21%), nucleolar (14.65%) and mitotic apparatus/cytoplasmatic (3.18%). The mixed and nuclear autoantibodies patterns were observed in exposed communities (p<0.01). In addition, various widely recognized autoimmune disease specific autoantibodies were also found, which occurred more frequently as following: NuMa1, PM/Scl, Ssa-Ro, rRNP/Sm, golgi/Ssa/Ro, PCNA, rRNP, Ku, besides other autoantibodies without defined specificity. The intensity of immunofluorescence was more reactive in riverine of the Tapajós (p<0.0001). Analysis by regression logistics multiple indicated that the risk of autoantibodies present in serum was twice higher in riverines exposed to mercury (>10μg/g) with age group above 50 years (p>0.01). Finally, additional studies are indispensable to confirm the specificity of these autoantibodies associated with the mercurial exposure, as well as to elucidate the mechanisms immunotoxicologicals of action of the mercury on the human immune system.
Acesso aberto (Open Access)
O Papel da pesca na eficiência reprodutiva dos ribeirinhos do baixo Tocantins: o caso do município de Mocajuba - PA
(Universidade Federal do Pará, 2013-04-22) ALMEIDA, Inailde Corrêa de; COSTA, Francisco de Assis; http://lattes.cnpq.br/1820238947667908
This work aims to analyze the knowledge of traditional communities in natural resource management through its productive activity, fishing approach of Reproductive Efficiency and Technological Trajectories notion, and thus valuing local knowledge, coupled with their territoriality constitution, as issues crucial to the success of collective management as a basis for sustainable development. Knowing traditional with the assumptions of reproductive efficiency, enabling a rational process and inherent agents that build productive strategies, grounded in multispecies, especially in the use of space and technology, the main mitigating action to ensure the sustainability of human activity in context Amazon. Because this was a study of a more qualitative, were analyzed: a) the historical formation of the city of Mocajuba fishing in the region Lower Tocantins, the natural foundations of spatial scenarios prevailing in research and aspects of rationality and standards production and reproductive performance of economic agents. The results showed us that the rationality of reproductive efficiency has proven effective in the analysis, with the value found in h converging to 1, in other words, the field shows that fishing provides comfort to those in work, represented in the modus vivendi of the agent, to reflect its form of social interaction that same scenario in capitalist societies are constituted, markedly, by its social bases family intertwined in the construction and reconstruction of the natural environment to sustain strong relationships of solidarity and cooperation as its core brands. The configuration of social organization fishing emphasized the model of bipolar division, determined by age and sex, seated in the domestic hierarchy and relationship of human productive force. Technological developments occurred in the Lower Tocantins, affected the fishing, and based on new quirk space optimization fishing. In this sense, technological changes, show up, reducing the effective execution time, increase stamina and enhance the productive yield, without thinking unlink conservation agent. It was evident that the fisheries conducted in the study area, is multispecific, developed dynamically in the different fishing methods employed at each annual seasonal cycle applied in different habitats. Thus, we conclude this paper that the ecological consciousness of the peasant and the value of traditional knowledge is paramount for successful fishing, however, this knowledge is often overlooked by the environmental authorities, but should be considered and consulted so that they can support measures for effective management environment to thrive.
Acesso aberto (Open Access)
A pesca comercial dos tucunarés Cichla Spp. (Peciformes, Cichlidae) no Reservatório da UHE-Tucuruí, Rio Tocantins, PA
(Universidade Federal do Pará, 2007) BOTELHO, Marília Cunha; BARTHEM, Ronaldo Borges; http://lattes.cnpq.br/4192105831997326
This study describes the freshwater fishery based on peacock bass ("tucunaré") Cichla spp. in the lower Tocantins River, Pará state, northern Brazil, in the area influenced by the Tucuruí hydroelectric dam, with emphasis on the reservoir. The study was divided in two parts: Chapter I describes the commercial peacock bass fishery with relation to fishing gear, fishing strategies, utilized environments, seasonality, and local fishing management according to the fishermen’s perception. The fishermen’s local knowledge was studies, including their ethnobiological classification of peacock bass types, and the social, ecological, and economical aspects involved. Interviews with fishermen and participation observation were conducted in situ. The Tucurui reservoir peacock bass fishery is of great importance in the social and economic life of these fishermen and is their main income source. This fishery occurs in specific places in the lake and uses rudimentary methods and equipment. According to the fisherman, production is influenced by environmental variables and by the use of guild nets, that the fishermen say drives away peacock bass from the fishing environments. The use of environments for fishing is the main source of conflict among fisherman. Social relations among fishermen in a system of partnership and the presence of middlemen diminish the the fisherman’s income. Fishermen possess consistent knowledge on the ecology and behavior of peacock bass. Their system of fish classification recognizes three ethnospecies, two of which constitute a single scientific species. Chapter II treats peacock bass yields at landing points in the lake, from 1997 to 2003, according to data furnished by ELETRONORTE, and a measure of fishing effort was considered that was most adequate for these data. The data were analyzed according to port, fishing gear, type of boat, fishing grounds, and river flood cycle. The data demonstrated that different cities possess fishing fleets with their own characteristics and that these utilize nearby fishing grounds. The greatest yields were during periods of flooding and subsidence of water levels, with hook and line fishery being responsible for most of the catch. Canoes were the most used boats. The yield data at landing points indicate that this fishery is more important in cities and areas located on the lake. Fish yield for unit of effort only shows adequate statistical behavior when analyzed for fishing grounds and the adjusted units of effort are number of fisherman per days of fishing, after logarithmic transformation.
Acesso aberto (Open Access)
A política de regularização fundiária e reforma agrária: o PAE nas ilhas do Pará
(Universidade Federal do Pará, 2011-10-13) MAIA, Rosane de Oliveira Martins; RAVENA, Nírvia; http://lattes.cnpq.br/0486445417640290
This thesis studies the Land Reform and Land Settlement Policy in the Amazon region, from the Second National Plan for Land Reform (PNRA II), which inserted the traditional riverine populations in the whole of its audience. We focus on the analysis of settlement projects in the municipalities of the Lower Tocantins Microregion islands (State of Pará). The project was conducted by a task force formed by INCRA (The National Institute of Colonization and Agrarian Reform) and SPU (National Secretary of the Federal Government Heritage). However, the proposed use and democratization of land ownership, which allows land to be secured for the riverine populations, was not strategically planned and prioritized by government institutions. Through the analysis of the decision-making process, the action plans of some institutions, the perceptions of data collection by the associations of the settled people, and the outcome of elections from 2000 to 2010, we conclude that the settlement projects were intensely carried out in a disorderly fashion, aiming to respond to the Lula administration’s land reforming indices in order to create a positive impact on election results which were essential to maintain the governing political system.
Acesso aberto (Open Access)
Seletividade de captura, dinâmica populacional, análise de estoque e sustentabilidade da pesca de Hemiodus unimaculatus (Bloch, 1794) a montante da barragem de Tucuruí, Brasil
(Universidade Federal do Pará, 2013-04-23) MARTINS, Jeronimo Carvalho; CINTRA, Israel Hidenburgo Aniceto; http://lattes.cnpq.br/6632466008150577; SARPEDONTI, Valérie; http://lattes.cnpq.br/2358097649881792
Hemiodus unimaculatus (Bloch, 1794) is one of the main species landed into the area of influence of Tucuruí Hydroelectric plant; however there is little information available about the fishery and biology of the species in the area. Therefore, this study aims to investigate spatial changes of H. unimaculatus, determine selectivity curves for the fishing nets used and calculate some parameters of population dynamics. The study area was located on Tucuruí’s dam, including the reservatory (flooded area) and up-river section. The samples were colected on a quaterly basis for the years 2001, 2003, 2005, 2006 and 2006, and semiannually in 2002 and 2004, in five areas located in the lake and two areas upstream, usinga battery of gillnets 50 m long and 3 m high, with a stretched mesh size of 40, 60, 80, 100 mm between opposing nodes. The Kruskal-Wallis test was used to compare mean total length and weight of the specimens at a significance level of 5%, the spatio-temporal variation of the catch was determined by cluster analysis and the SIMPER; selectivity for network construction curves selection, and population aspects (growth, longevity, mortality, recruitment and yield per recruit) with the aid of the FISAT II. Results showed that females were bigger and heavier than males. During the first period (2001 – 2003) the study area was shared in spawning grounds and growth, while in the final period (2005-2007) there was no difference in the use of space. The mesh of 60 mm is the most suitable for fishing, considering the capture of 50% of adults. The sex ratio was 1.44:1 favorable to females (χ2 c = 28.86; p < 0.0001). Relations total weight / total length showed a positive correlation and did not differ between sexes (t = -0.097; p = 0.9229), with males and females exhibited isometric growth. The condition factor was not different between the sampling points, suggesting that the species uses the entire study area as a feeding zone. The von Bertalanffy growth parameters were L∞ = 358 mm, k = 0.55 yr-1 and t0 = -0.15 year. The average total mortality and natural were 3.04 yr-1 and 0.7 yr-1, respectively. The exploitation rate was estimated at 0.77 and the yield per recruit showed that the rate of exploitation of the H. unimaculatus stock should be reduced by 52% to maintain the recruitment and spawning. So with all the information generated, it can be seen that change in the structure and spatio-temporal dynamics of H. unimaculatus is a process of continuous adaptation and appropriate fisheries management becomes essential for the preservation of the species. To reach this goal, it is necessary to review the current fisheries legislation, seeking an optimal mesh size for catching the species, decrease the rate of exploitation and regularly monitor the selectivity and population parameters.