Influência da heterogeneidade ambiental e distância geográfica na composição de espécies do gênero Piper (Piperaceae) em floresta de terra firme no interflúvio Madeira-Purus, Amazônia Central
Mechanisms involved in plant distribution patterns are mainly mediated by environmental determinism and/or by historical processes and dispersal limitation. However there is not a consensus regarding which of these have a higher relative importance in structuring plant communities in the tropics....
| Autor principal: | Bernardes, Carolina |
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| Grau: | Dissertação |
| Idioma: | por |
| Publicado em: |
Instituto Nacional de Pesquisas da Amazônia - INPA
2020
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| Acesso em linha: |
https://repositorio.inpa.gov.br/handle/1/11968 http://lattes.cnpq.br/3218472556248041 |
| Resumo: |
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Mechanisms involved in plant distribution patterns are mainly mediated by environmental
determinism and/or by historical processes and dispersal limitation. However there is not a
consensus regarding which of these have a higher relative importance in structuring plant
communities in the tropics. This study aims to determine the effects of canopy openness, litter
depth, soil cation and texture content and palm species abundances on Piper species
composition at the mesoscale and to determine the relative importance of geographic and
environmental distances in determining the variation of beta diversity of Piper community at
the large scale of the Madeira-Purus interfluve in the Central Amazonia. At the mesoscale we
inventoried Piper species composition and collected data on environmental variables and
palm species in 41 plots of 250 x 5 m placed in terra firme forest. At the large scale we placed
nine 500 x 5 m plots along the BR-319 in Madeira-Purus interfluve. In mesoescale, Piper
species composition was significantly related to litter depth, soil texture and abundance of
Lepidocaryum tenue and Oenocarpus bataua. Influence of edaphic components on tropical
plant communities has already been documented. However, the strong effect of litter variation
on plant community structure was not yet demonstrated, despite its known influence on
species development. Given that Piper species composition had a significant relationship with
palm species abundances. So palms can be used instead of environmental variables as
predictors of Piper species composition. At the larger scale geographic distance alone was
significantly related to beta diversity of the Piper community. At the regional scale, the total
variance of the beta diversity of the Piper community explained by multiple regression on
geographic and environmental components, based on quantitative data, was 22%. From
which, 6 % were explained by pure geographic distance, 8 % by pure environmental distance
and 8 % by the mixed environmental-geographic component. Yet, 78 % of the variation
cloud not be explained by the variables used in the multiple regression models. The total
variance of the beta diversity of the Piper community explained by multiple regression on
geographic and environmental components, based on qualitative data, was 23%. From which,
22% were explained by pure geographic distance and pure environmental distance didn’t
contribute to explain its variation. Yet, 77 % of the variation cloud not be explained by the
variables used in the multiple regression models. This study differs from previous studies as it
gives almost no importance to environmental conditions in explaining the variation in Piper
beta diversity, highlighting the importance of historical and dispersal limitation processes in
the maintenance of Piper community beta diversity at the regional scale (.> 100 km). |