Estrutura de comunidades de macroinvertebrados em riachos: efeitos de diferentes condições de perturbação sobre os processos de colonização e recolonização de substratos
Carregando...
Data
2011-08-29
Autores
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Federal de Goiás
Resumo
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.
Descrição
Palavras-chave
Insetos aquáticos , Distúrbio , Perturbação , Colonização , Riachos , Cerrado , Aquatic insects , Disturbance , Colonization , Streams , Cerrado
Citação
HOLANDA, Luis Fernando Rabelo. Estrutura de comunidades de macroinvertebrados em riachos: efeitos de diferentes condições de perturbação sobre os processos de colonização e recolonização de substratos. 2011. 83 f. Dissertação (Mestrado em Ecologia e Evolução) - Universidade Federal de Goiás, Goiânia, 2011.