The present study aims to enrich the scientific and technical knowledge on a Mixed
Araucaria Forest fragment and, for that reason, this study was divided into five
chapters with specific goals. The first chapter describes the general aspects of this
research. The second chapter analyzes and compares the changes in floristic,
phytosociological and structure, as well as mortality and recruitment. The third
chapter evaluate the changes in species growth, botanical families and of the forest
as a whole, relating them with the meteorological variables in the region. The fourth
chapter tested accuracy of diameter projections, using the transition matrix and
movement ratio models in different temporal amplitudes and diameter class intervals.
The fifth and last chapter simulates the growth in number of trees and basal area
inside the forest as a whole, botanical families and species with the greater
importance value, using movement ratio model. For this pourpose the used data
proceeded from a continuous inventory conducted in a Mixed Araucaria Forest
fragment with three permanent sample plots of 1 ha each and one permanent plot of
0.5 ha, subdivided in 350 subunits with 100 m2 and 3.5 ha of sampled area, which
were measured annually ever in July since 1995 up to 2011, in the Experimental
Station Rudi Arno Seitz, in the São João do Triunfo, Paraná. All trees with diameter
at breast height equal or greater than 10.0 cm (DBH ≥ 10.0 cm) were identified and
measured, and during remeasurements all recruited and dead trees were counted
until the year 2011. The results showed that that fragment had high floristic diversity
and has changed little over the years. The Lauraceae and Myrtaceae had greater
diversity and representation in this forest as well as the species Araucaria
angustifolia, Nectandra grandiflora, Ilex paraguariensis and Matayba elaeagnoides.
The diameter distribution presented the decrescent form, typical behavior of allaged
and mixed forests. The average recruitment rate was higher than the mortality rate in
this fragment. The mean periodic diameter increment of the forest presented an
average of 0.22 cm.ano-1, but the increment values vary in relation to species. The
growth rate of the forest and for each species changed over the years, maintaining a
gradual growth, apogee and after senescence, even when one observes the same
diameter classes over the years. The results of diametric projections indicated that
the movement ratio model with temporal amplitudes of 2 years and diameter class
intervals of 10 cm are the most recommended to the realization of the prognosis of
the number of trees. In the future, the forest as a whole will grow considerably in
basal area, but not in number of trees, confirming the maturation of this Mixed
Araucaria Forest fragment.
