Comunidades de macroinvertebrados bentônicos e a relação com os diferentes usos da terra no sudoeste de Goiás

• Autor(a) principal: Rocha, Hudson Moraes
• Data de Publicação: 2018
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/8541
• topic: Biomonitoramento; Classificação hidrológica; Paisagem do cerrado; Biomonitoring; Hydrological classification; Cerrado landscape; GEOGRAFIA FISICA::HIDROGEOGRAFIA

The water, during its circulation process, suffers alterations in its quality due to the anthropic actions and of the themselves environmental interrelationships with water resources. The incorporation of the natural lands of the Cerrado areas for the development of agriculture and livestock has been intense, causing damage to human health and a substantial loss of habitats and biodiversity of aquatic ecosystems. In environmental studies, the benthic macroinvertebrate communities are importants environmental indicators in assessing water quality. The present research aims to evaluate the influence of land use and occupation and the structure of the lotic environment in the distribution and structuring of benthic macroinvertebrate communities. The sampling of the fauna were realized in the period from August to November 2014, corresponding to the dry season in the Cerrado. The study was conducted in nine sub-basins (agricultural areas, livestock areas and preserved or partially preserved areas) in the Southwest of Goiás, totaling 137 sampled rivers. The data used were: taxonomic abundance of benthic macroinvertebrates, with taxonomic classification at family level; the physical and chemical data of water (in situ); the land use and occupation data - agriculture, livestock and preserved, from the sampling points. The applied methods for the analysis of the data were: analysis of richness and taxonomic abundance to infer the composition of the aquatic fauna; analysis of variance to verify the effects between land use variables and the hydrological classification of rivers in relation to richness and abundance of taxa; canonical correspondence analysis to infer the patterns of variation in the composition of the biological community, explained by environmental variables, relating to land use and occupation. According to the results, the flow, water velocity, depth of the rivers, and the dissolved oxygen at the level of P <0.05 were significantly higher in the rivers near the areas of agriculture and livestock in relation to the preserved areas. In total, 11,884 individuals were collected and identified in 72 families. In the rivers located in agricultural areas, the Simuliidade family was the predominant in the stretches of 1st to 2nd orders, rivers of less current and depth. In the Analysis of Variance, it was verified that the abundance of the functional group of collector-filter was dominant in all orders of rivers studied in the preserved areas, reaching the highest significant averages in the stretches of rivers from 4th to 6th orders. The Canonical Correspondence analysis produced a similarity diagram of the fauna in relation to the physical and chemical parameters for each type of land use and occupation. In the application of the study of the richness distribution and abundance of benthic macroinvertebrates, it was observed that the hydrographic basins of predominantly agriculture and livestock use had a loss of taxa, with a predominance of generalist taxa and, while in the rivers of preserved areas present the highest richness and taxonomic abundance.