Florística, distribuição e diversidade beta da comunidade arbórea ao longo do gradiente ambiental hídrico em uma floresta de terra firme no interflúvio Purus-Madeira, Amazônia Central
For a better understanding about how environmental variables influence species distribution a thorough knowledge of the flora of tropical forests is needed. Recent studies have investigated how environmental conditions influence the distribuition of tree species in tropical forests. Soil properti...
| Autor principal: | Souza, Priscila Figueira de |
|---|---|
| Grau: | Dissertação |
| Idioma: | por |
| Publicado em: |
Instituto Nacional de Pesquisas da Amazônia - INPA
2020
|
| Assuntos: | |
| Acesso em linha: |
https://repositorio.inpa.gov.br/handle/1/12783 http://lattes.cnpq.br/7765128988310467 |
| Resumo: |
|---|
|
For a better understanding about how environmental variables influence species
distribution a thorough knowledge of the flora of tropical forests is needed. Recent
studies have investigated how environmental conditions influence the distribuition of
tree species in tropical forests. Soil properties and topography are the most frequently
used predictor variables and indirectly reflect the hydrological conditions of a region.
Nevertheless, the direct relation of water availability and distribution of tree species is
poorly explored.
We inventoried the tree community (DAP > 10 cm) in an upland forest of the
Purus-Madeira interfluvial in 12 plots of 250 x 40 m distributed over approximately 700
km in a North-South gradient in Central Amazonia. The material collected will be
deposited in the herbarium of the Instituto Federal do Amazonas (ETAM). We
identified 655 species in 193 genera and 56 botanical families totaling 3.708
individuals. From these, 263 species (40%) were considered rare, with only one
individual among the 12 plots. The most abundant and richer families were
Lecythidaceae, Fabaceae, Sapotaceae and Chrysobalanaceae. The species with higher
IVI were Eschweilera coriacea, Eschweilera truncate e Licania micrantha. The tree
community was related to local water conditions through two related measures, the
vertical distance from the nearest drainage (HAND) and flooding. The quantitative and
qualitative compositional data of the floristic composition were sorted using NonMetric Multidimensional Scaling (NMDS). The environmental variables of local water
conditions, precipitation in the driest months and soil silt content were related to the
axes of the NMDS through regressions. The percentage of silt in the soil and local water
conditions were related to the change in the floristic composition of trees.
Precipitation in the driest months was weakely related to the composition of
local flora, but plays a fundamental role in the composition of the local water
conditions. All three predictor variables have an important role for effective availability
of water for the trees. |