Influência da mata ripária na estrutura das assembléias de riachos da bacia do alto rio Paraná em Goiás, Brasil

• Autor(a) principal: VIEIRA, Thiago Bernardi
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tde/2556
• topic: interações ecológicas, riqueza, habitat aquático; 1. Interações ecológicas 2. Riqueza de espécies 3. Habitat aquático; ecological interactions, richness, aquatic habitat.; CNPQ::CIENCIAS BIOLOGICAS::ECOLOGIA

The presence of riparian vegetation is an important factor that strongly influences such river characteristics, which consequently maintain local habitat heterogeneity and contributes to the input of allochthonous materials. Therefore, this dissertation has two objectives: 1) to compare the interaction of fish assemblages with riparian vegetation that belongs to the streamlet Santa Maria, Meia Ponte, Piracanjuba Rivers basins, rivers located in the Northern portion of the Paraná River basin, Central Brasil, identifying possible structures relating basins and rivers orders to the vegetation cover percentage, availability of allochthonous and authochthonus matters and water turbidity; 2) determine which habitat variables (geomorphology, riparian vegetation, limnological, physical-chemical and hydrological aspects) influence streamlet fish assemblages found within in the Northern Paraná River Basin. In order to do so, during April and September 2009 samples were performed in 27 streamlets of first and second orders from Meia Ponte River (seven tributaries), Piracanjuba River (14 tributaries) and Santa Maria Streamlet (six tributaries) located in the Southeastern region of the state of Goias (Northern Paraná Basin). By the end of the samples, 4879 specimens from 59 species and 19 families were collected. Species richness, individual abundances by guilds and total biomass did not presented significant differences among the three basins considered. However,when the streamlets order were considered, such difference was significant. The difference between first and second order streamlets when considering species richness was, on average, of eight species and the highest species richness was found among second order streamlets. Individual abundances found by trophic guilds presented differences among, carnivorous, herbivorous and insectivorous species, and in all cases, the species richness was higher in the second order streamlets. Total biomass presented an average increase of 131g in the second order streamlets. From the 18 habitat descriptive variables analyzed, eight influenced the local fish assemblages: two of them were quantitative ones (margins cover type and deposited matter in the streamlet bed) and six were quantitative (stream velocity, river width, dissolved oxygen, water conductivity, water temperature and water turbidity).