Variação geográfica e intraespecífica da densidade básica da madeira do gênero Eschweilera (E. coriacea e E. truncata) no estado do Amazonas.
Many uncertainties exist in the estimates of carbon stocks and the capacity of sequestration of carbon in tropical forests. Wood specific gravity (WSG) has been used as a variable in models to estimate forest biomass. However the average values used for wood density for each species neglects the...
| Autor principal: | Schmitt, Adalberto Rodrigo Kossmann |
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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/1/5156 http://lattes.cnpq.br/2445924231484008 |
| Resumo: |
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Many uncertainties exist in the estimates of carbon stocks and the capacity of
sequestration of carbon in tropical forests. Wood specific gravity (WSG) has been used as a
variable in models to estimate forest biomass. However the average values used for wood
density for each species neglects the variation in wood density of a particular species in
different areas. Also, the sampling method used to evaluate the average density of each tree
should consider the radial and axial variations in the WSG. The objective of this research was
to determine the variations in the WSG of Eschweilera coriacea (DC.) S. A Mori, inside of
the tree and among spatially different locations within the State of Amazon, to determine the
results of using the average WSG in the estimation of forest biomass. Destructive sampling
was used in the collection of 28 trees with a diameter at breast height of between 18 and 38
cm. The sample locations were distributed in six municipal districts of Amazons State. The
trees were sawn into sections of 10 cm in thickness in the locations at the base of the bole,
DAP, half way up the bole and top of the bole. The basic density of the wood was determined
following the norm ASTM (2007). The basic density of the wood of E. coriacea varied within
the individuals in the radial direction (p: 0.00079), in the axial direction (p: 7.27e -09) and
among sites (p = 0.000324), demonstrating that variation exists in the basic density of the
wood for the same species and among sites. Data of basic density collected at one site to
evaluate the biomass in another site generated errors of up to 24%. The sampling method was
developed to evaluate the basic density of the function of the axial and radial position at a
given sampling point. The average density in the axial position of the DAP was found to be a
representative density of the medium density of the tree (R²: 0.98; p < 0.0001). The
proportion of 20% of the ray of the tree represents the density basic average of the tree for the
E. coriacea (R²: 0.94; p < 0.0001), indicating that is possible to adapt the collection of the
sample correctly to esteem the density. These results demonstrate that not taking into account
variation among sites can cause significant error in the estimation of forest biomass. The
method employed here to estimate the density of the tree based on a percentage of the ray was
shown promising in standardization of the sampling of the tree in a representative way. |