Teses em Ecologia Aquática e Pesca (Doutorado) - PPGEAP/NEAP
URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/3501
O Doutorado Acadêmico iniciou em 2007 e pertence ao Programa de Pós-Graduação em Ecologia Aquática e Pesca (PPGEAP) do Núcleo de Ecologia Aquática e Pesca da Amazônia (NEAP) da Universidade Federal do Pará (UFPA).
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Item Acesso aberto (Open Access) Ecologia da ictiofauna do estuário do rio Paciência, Ilha do Maranhão - Brasil(Universidade Federal do Pará, 2012-02-23) SILVA JÚNIOR, Milton Gonçalves da; CASTRO, Antonio Carlos Leal de; http://lattes.cnpq.br/9450410023114396; SAINT-PAUL, Ulrich; http://lattes.cnpq.br/5897104750785224Estuarine systems constitute an important habitat for different species of fish. From the ecological standpoint, the ichthyofauna plays an important role in the energy balance between trophic levels in estuarine ecosystems. Thus, the following were aims of the present study: determine the spatiotemporal distribution of the ichtyofauna; explain behavioral and ecological characteristics; compare the composition of relative biomass, ecological and functional guilds in different estuarine systems in northern Brazil; investigate the influence of biotic and abiotic variables and correlations with the biological patterns of the ichthyofauna; and identify changes in the biotic integrity of the tidal creeks studied. Data were acquired through bimonthly sampling in the Iguaiba, Grande and Cristovao tidal creeks between January 2006 and September 2007, using gillnets and block nets. Samples were also taken of the surface water for the determination of physicochemical parameters and dissolved inorganic nutrients. Diversity, evenness and richness indices were employed for the ecological characterization of the species. The biotic integrity index was used to assess the effects of possible environmental changes on the ichthyofauna. Univariate (ANOVA, Kruskall-Wallis) and multivariate (Cluster, nMDS, SIMPER, COIA and ABC curves) statistical methods were used to compare species and capture sites. A total of 12,219 individuals distributed among 55 species and 27 families were caught. The families Sciaenidae, Ariidae, Carangidae, Engraulidae and Mugilidae had the greatest species richness. Ariopsis bonillai and Cetengraulis edentulus made the greatest contribution to the formation of similar groups. Stellifer naso and Cynoscion acoupa were responsible for the dissimilarity between the groups formed. Approximately 66% of the fish caught were juveniles, thereby confirming the use of estuarine systems as nurseries. The records between the Marajoara and Maranhao Gulfs indicate the occurrence of 140 species. Marine occasional visitors and freshwater species occurred occasionally. Marine estuarine-opportunists and estuarine dependents species made the largest contribution to the Maranhão Gulf, whereas estuarine residents species had high biomass values in all estuarine systems investigated. Detritivores occurred mainly in the state of Para and zoobenthivores were found mainly in the state of Maranhao. The occurrence of piscivores was inversely proportional to the abundance of juveniles. The co-structure formed between environment-fish parameters was significant. Salinity, pH, silicate, ammonium, phosphate and nitrate exerted an influence over the structure of the fish community. No species were associated with environments with high concentrations of inorganic nutrients. The ABC curves revealed that the estuarine environment is moderately disturbed and the integrity index characterized the environmental quality of the tidal creeks as very poor to fair. The presence of juveniles demonstrates the importance of tidal creeks to fish development. The ichthyofauna analyzed in the present study exhibits seasonality with regard to hydrological periods. The fish community in tidal creeks can serve as an indicator of the quality of ecosystems submitted to tidal pulses. Therefore, the protection of tidal creeks in mangroves is essential to the management of fishery resources, considering the strong association between ichthyofauna abundance and the structural composition of the habitat.Item Acesso aberto (Open Access) Ecologia, pesca e dinâmica populacional do camarão-da-Amazônia - Macrobrachium amazonicum (Heller, 1862) (Decapoda:Palaemonidae) – capturado na região das ilhas de Belém - Pará - Brasil(Universidade Federal do Pará, 2011) SILVA, Bianca Bentes da; MARTINELLI-LEMOS, Jussara Moretto; http://lattes.cnpq.br/5264841936875017; ISAAC, Victoria Judith; http://lattes.cnpq.br/3696530797888724In monthly biological samples of M. amazonicum in Guajará Bay and Mosqueiro island, were studied reproduction, density, morphometric relationships and population dynamics. Two other sample designs was realized in two perennial the same estuary. Results indicate differences in capture of this species using different bait of meal, but is solely on the abundance and population structure does not change. The species is most abundant in the dry season, supporting the idea higher catchability of fishery resources. In Combu island was found species with larger sizes. Females are significantly larger and heavier than males, indicating the differentiation in metabolism due to reproduction. Sex ratio of males is higher in smaller size classes, which may indicate an increase in predation on smaller sizes of males due to their behavior more aggressive than the females or males simply because they reach lengths larger than females are more heavily preyed upon by fishing, with the recruitment of only the smaller males. First maturation length for both sexes resulted in 11.5 mm – carapace length - (11.5 mm in males and 11.2 mm in females). Reproduction in M. amazonicum is continuous or periodic a gradual increase during the months from October to March. The most common sites housed, as inner regions of tidal channels or holes (common in Amazon estuary) sites are preferentially sought by mature females for spawning and juvenile growth. Von Bertalanffy growth parameters obtained were very similar between the sexes, where L ∞ = 44.8 mm and K = 0.35 for males and L ∞ = 46.5 and K = 0.31 for females. Mortality and exploitation obtained was in maximum sustainability and the management should be treated fairly care. In this situation, any increase in effort may result a state of over-exploitation of growth. Allied to near commitment of the stocks of M. amazonicum of the socio economic fishing is no different from other systems of coastal fishery Para: poor education, poor performance of professional associations, chain productive complex and that its main underprivileged. We suggest the statistical monitoring of production, the delineation of the minimum capture length in 4.5cm; suppression of fishing with matapis in headwater areas of creeks and tidal channels, a census of users and the use of models bioeconomic that include major aspects of its biological and productive chain.Item 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/4779271407117528The 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.