Fatores determinantes da distribuição de aves no interflúvio Purus-Madeira
Studies addressing deterministic and stochastic processes that effect changes in species composition among sites (beta diversity) have focused, for the most part, on sessile organisms. These are highly susceptible to random dispersal processes, confirming neutral theory assumptions. At first glan...
| Autor principal: | Menger, Juliana da Silva |
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| Grau: | Dissertação |
| Idioma: | por |
| Publicado em: |
Instituto Nacional de Pesquisas da Amazônia - INPA
2020
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| Assuntos: | |
| Acesso em linha: |
https://repositorio.inpa.gov.br/handle/1/11993 http://lattes.cnpq.br/7611745246165159 |
| Resumo: |
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Studies addressing deterministic and stochastic processes that effect changes in
species composition among sites (beta diversity) have focused, for the most part, on
sessile organisms. These are highly susceptible to random dispersal processes,
confirming neutral theory assumptions. At first glance, birds would appear to have
high dispersal ability. However, in Amazonian forests most birds are extremely
sedentary, with restricted distributions, often limited by large rivers. In this study, we
evaluated the environmental effects (palm species composition) relative to
geographical distances between sites, as factors related differences in forest bird
species composition. We sampled 11 sites in upland forest, separated from one
another by 60 km, covering a 670 km extension in the Purus-Madeira interfluve of
Western Amazon, Brazil. Similarity in bird assemblage was significantly correlated
with palm species composition. Understory and canopy birds assemblages showed
similar correlation with palm species composition. When the effect of palm species
composition was controlled, distance was not a good indicator of changes in the bird
community. Our results suggest that, in this region and at this spatial scale, birds are
not limited by geographical distance and can disperse throughout the region studied.
Nevertheless, they are not uniformly distributed which can best be explained by
environmental variation, represented here by palm species composition. Although
our results indicate that geographic distance has no effect on changes in bird
composition, we emphasize that studies on a larger spatial scale could help to
understand dispersal limitation effects in tropical Amazonian forest bird composition. |