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).

Navegar

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Ecologia da ictiofauna e análise ecossistêmica das áreas de influência direta da UHE Coaracy Nunes, Ferreira Gomes - AP
(Universidade Federal do Pará, 2012-04-25) OLIVEIRA, Júlio Cesár Sá de; NAHUM, Victoria Judith Isaac; http://lattes.cnpq.br/3696530797888724
The reservoir of UHE Coaracy Nunes in Araguari is located between the cities of Porto Grande and Ferreira Gomes in the state of Amapá, Brazil, lying 200 km from the Atlantic Ocean. The Coaracy Nunes was the first dam to be built in the Brazilian Amazon, with its works started in 1967. The Araguari river is the main of the state of Amapá and represents a source of income generation through fishing, farming activities in their floodplain, navigation, mining, power generation and recreation. The present study aimed to assess the changes imposed by the construction of the reservoir of UHE Coaracy Nunes, through the fish assemblages of four areas of direct influence of this plant. For this, from May 2009 to July 2010, fish collections were made bimonthly, with standardized mesh networks ranging from 1.0 to 10.0 cm between knots and other technical aids. From these collections, in the Chapter 1 was investigates the composition, abundance (CPUEn) and biomass (CPUEp) on the fish fauna, sampling efficiency (collector curve, rarefaction curves and Jacknife) and descriptors of ecological communities (richness, diversity, evenness and dominance) of the assemblages of the four areas. We conducted analyzes of variance (ANOVA: factorial), Kruskal-Wallis, t-test and Mann-Whitney test to see if there were significant differences between the descriptors of the areas and seasons. These analyzes were corroborated by multivariate analysis of grouping (cluster), spatial (MDS) and ANOSIM Simper. In chapter 2, the ecological status of the four areas were verified using as indicators: species abundance curves, curves and Kdominance curves ABC, as well as species-abundance models geometric series, log series, log normal and broken stick, and regression model linear size spectra. In chapter 3, the trophic structure was estimated from the categorization of species in each area five guilds: piscivorous, omnivorous, detritivorous, carnivorous and herbivorous. The abundance, biomass and ecological indexes of these guilds were estimated and verified their spatial and temporal variations, by analysis of variance (ANOVA: factorial and Kruskal-Wallis) and Student t test. In chapter 4, the diet of most abundant species assemblage of each area was checked and their spatial and temporal variations detected by analysis of variance (ANOVA: factorial and Kruskal-Wallis). Also estimated the breadth and niche overlap of the most abundant species, as well as the existence of competition between species through modeling zero. In chapter 5 was evaluated four areas of the ecosystem through flow models of biomass in the ecosystem food web, using as a tool for modeling software Ecopath. These analyzes were designed to describe the changes in ecological attributes that quantify the properties of maturity, stability and resilience ecosystem that could reflect the ecological status of these areas. The model included functional compartments from primary producers to top predators. In general, all analyzes indicated significant changes in fish fauna attributed to the implementation of UHE Coaracy Nunes, reflected in the three organizational levels: ecosystem, community (assembly) and guild. The results indicated the capture of 1977 fish divided into two classes, 9 orders, 23 families, 73 genera and 108 species. The species accumulation curves and rarefaction curves showed that samples areas were sufficient to Reservoir and Lacustrine areas. The results showed that the area downstream was more rich, diverse and equitable in relation to other areas and did not influence the seasonal variation in these rates. The relative abundance (CPUEn) was higher in areas Reservoir and Lacustrine and relative biomass (CPUEb) was higher in the downstream, with no seasonal differences for these descriptors in all areas. The cluster analysis (cluster) and spatial (MDS) of the fish fauna permitted to identify the formation of three distinct assemblies: Downstream, Upstream and an assembly comprising Reservoir and Lacustrine areas, confirming the similarity of these two areas. The results of the curves whitake-plot, ABC and K-dominance, as well as the satisfactory adjustment of the broken stick model and the patterns of currvas spectrum size to the assembly area downstream indicate that this area was the most balanced in terms of ecology. Reservoir and Lacustrine areas, the results of both the model adjust geometric series, as the results of the curves whitake-plot, ABC and K-spectrum dominance and size as well as the results of the curves and adjustments to the model spectrum and lower logserie size for the assembly of the reservoir area, reflect that fish these areas, most of them are little guys with high dominance and low evenness, featuring typical of communities impacted areas. The trophic structure of fish assemblages in areas dammed (Reservoir and Lacustrine) formatted according to the bus of the river, which was isolated and fragmented environment, determining their physical modification, requiring the establishment of a fish fauna species pre-adapted to environmental conditions impoundment, different, in part, the structure of the pre-river ichthyofauna bus, highlighting the piscivores, omnivores and detritivores that were the richest and most abundant in the availability in the two areas of food resources of your choice. The results showed that the diets of the assemblies of all areas were similar to the prevalence of consumption of fish and debris, followed by allochthonous plant food, revealing a pattern with a few large clusters and a higher concentration of species with narrower niches. However, the pattern of low amplitude was evidenced by trophic guild dominance of piscivores, added to the detritivore and herbivore guilds. Seasonality little influence on the supply of most species in all areas. The comparative patterns of diet among the areas upstream and downstream to the Reservoir and Lacustrine areas indicate that most species of impoundment areas belonged to guilds piscivorous, omnivorous and detritivorous bus before the river, which colonized these environments, influenced mainly by abundance of food resources on their preferences and physical conditions are favorable. Competitive interactions were evidenced by the null model, suggesting that competition was also an important factor in structuring assemblages. Ecossistemicamente, the four flow models represent ecosystems with high biomass production primári coming from the riparian forest and filamentous algae, which are partially used. The detritus-based food chain had to be more important than that is based on primary aprodução Reservoir and Lacustrine areas. Most flow occurs in compartments lower trophic levels. The properties area downstream ecosystem indicate that this environment is further developed and couple, characterized by a high resilience and entropy. The area presented Reservoir ecosystem attribute features that conferred less resilient and more stable, but less than the couple areas of the river. The Lacustrine area presented attributes characterizing an environment of intermediate resilience, stable immature and at the same time. The Upstream area showed a pattern intermediate amount of resilience, stability and maturity.
Acesso aberto (Open Access)
Produtividade e rentabilidade da frota artesanal que captura serra, (Scomberomorus brasiliensis, Collette, Russo & Zavalla-Camin, 1978), na costa norte do Brasil
(Universidade Federal do Pará, 2012-04-25) ESPÍRITO SANTO, Roberto Vilhena do; NAHUM, Victoria Judith Isaac; http://lattes.cnpq.br/3696530797888724
The fisheries on the Brazil north coast, as well as the S. brasiliensis, has a great economic importance to the local fisheries communities. This resource have a seasonal production variation associated at the changes of the precipitation, with migrations to the northern hemisphere and to the Brazilian Northeast too. Your fishing is shared by many fleets of different Brazilian states and several countries, with no one management policies, for this stock. The Amapá state coast is comparatively more productive than that of Pará and Maranhão, but the fishing on the Pará coastline promotes a better economic return for small boats. Larger boats have a better economic income when their fishing are on the Amapá coast. Financing to a boat acquisition must be accompanied by a trained professional to guiding the fisherman, with a economic and technical information, to straight at a fishing activity with a better financial returns. The middleman, at this time, have a fundamental importance in the serra capture, capitalizing the fishing activity and are the major marketing agents of the production. A change in the economic profile of production and in the marketing chain is required, changing from a disorganized activity, artisanal and unprofitable to the fishermen, to a scale economy with less overhead and greater income. This only will happen with formation of associations and/or cooperatives. The professional training only will increase with the grow of the formal education level, because the education is a limiting factor for the technical learning of fishermen.

Navegar

Navegando Teses em Ecologia Aquática e Pesca (Doutorado) - PPGEAP/NEAP por Orientadores "NAHUM, Victoria Judith Isaac"