Tese
Análise dos fatores influentes sobre o crescimento de ipê – roxo (Handroanthus heptaphyllus Vell. (Mattos)) – um estudo de caso
Autor
Schröder, Thomas
Institución
Resumen
Red Lapacho is timber species with largest market value, considered along with
Mahogany, as 'green gold' in areas of natural forest logging. Therefore, the objective of
this study was to analyze the different factors that influence the growth of this species,
taking into consideration the spatial and temporal dependence inherent to the data. A
census of Red Lapacho individuals was carried out in a natural fragment of Subtropical
Deciduous Forest with approximately 13 hectares of area. Quantitative morphological
and diameter increment data were obtained for each tree of this species. Competitors
defined by Bitterlich plots were measured and identified, and a regular grid with infill
points of soil sampling were also analyzed. Spatial patterns of distribution of Red
Lapacho and its dimensions had completely spatial randomness patterns. Sampled
species richness from competitors was of 60 species and the competition generated by
them had a random spatial pattern as well. A model for the height – diameter
relationship using Generalized Additive Mixed Models (GAMM) produced better results
when the latent spatial pattern was included in the model. The spatial patterns of nutrient
availability were influenced by relief of the area and distance from the edge of the forest
and grassland environments. Anionic nutrients were strongly influenced by the spatial
dynamics of the two vegetation types while cations were influenced mainly by
pedogenesis. The spatio-temporal Bayesian diameter increment model developed for
the Red Lapacho trees showed that there was considerable inter – annual variation in
tree growth. The spatial variation in tree growth was closely related to the pedogenesis
of the area under study, more specifically, lower increments were observed in areas
where the soil had signals of water influence in tits formation. Using site proxies based
on geocentric, phytocentric and dendrocentric approaches was able to take into
consideration the spatial variation in the growth of Red Lapacho trees and, all
approaches may be utilized in the development of growth models.