Estrutura de comunidades de macroinvertebrados em riachos: efeitos de diferentes condições de perturbação sobre os processos de colonização e recolonização de substratos

• Ano de defesa: 2011
• Autor(a) principal: Holanda, Luis Fernando Rabelo
• Orientador(a): Oliveira, Leandro Gonçalves
• Banca de defesa: Oliveira , Leandro Gonçalves, Roque, Fábio de Oliveira, Garro, Francisco Leonardo Tejerina
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Goiás
• Programa de Pós-Graduação: Programa de Pós-graduação em Ecologia e Evolução (ICB)
• Departamento: Instituto de Ciências Biológicas - ICB (RG)
• País: Brasil
• Palavras-chave em Português: Insetos aquáticos; Distúrbio; Perturbação; Colonização; Riachos; Cerrado
• Palavras-chave em Inglês: Aquatic insects; Disturbance; Colonization; Streams; Cerrado
• Área do conhecimento CNPq: CIENCIAS BIOLOGICAS::ECOLOGIA
• Link de acesso: http://repositorio.bc.ufg.br/tede/handle/tede/4004

Disturbance events affect the colonization and re-colonization process of streams by benthic macroinvertebrates. The Intermediate Disturbance Theory predicts distinct community patterns resultant by disturbance, where we can found coexistence or species loss. Such patterns vary with intensity and frequency of disturbance plus species trait, which can provide resistance or resilience to the community. An experiment was carried out to test the immediate and during time effects of two intensities and three frequencies of disturbance on the benthic macroinvertebrates community at five Cerrado streams, at Goiás State, Brazil. We tested two hypothesis: 1) Disturbance affect the permanency probabilities of species on substrates along time, but it’s more likely for cylindrical body and high mobility groups of species than to hydrodynamic body and short life cycle species group; and 2) Disturbance events change the community composition of aquatic invertebrates, such a way that through time there’s a tendency of increasing similarity of community. The low intensity disturbance did not have an immediately effect on the occurrence probabilities of hydrodynamic body, large body or grabbing species group. However, increasing on disturbance intensity drove to a negative effect of all groups, except the Elmidae larvae with flattened body. Through time, we observed resilience of R-strategists groups, seeing that their permanency probabilities weren’t affected by disturbance intensity and frequency through time. Furthermore, high intensity disturbance caused an immediately effect on community composition between control and treatment differing the proportion off spatial turnover and nesting process, driving dissimilarities resultant from species loss. Nevertheless, there was no support for the increasing similarity resultant of replacement or species loss through time hypothesis. These results indicate that, despite of the distinguished immediate effect of disturbance, there’s a fast pattern of re-colonization of substrates, which results in non discrepant community structure pattern. The more likely effect of disturbance is a redistribution of individuals between the different habitats, generating unpredictability on detection of species by traditional methodologies.