TITLE:
Anthropogenic Disturbances and the Natural Vegetation Regeneration: A Case Study of a Forest Fragment Located in a Cuesta Relief Area, State of São Paulo, Brazil
AUTHORS:
Luiz Alberto Blanco Jorge, Vanessa Rodrigues Pereira
KEYWORDS:
Secondary Succession, Diameter Distribution, Spatial Statistics, Vegetation Structure
JOURNAL NAME:
Open Journal of Forestry,
Vol.5 No.6,
August
25,
2015
ABSTRACT: The
present study has been conducted in one of the five natural vegetation
fragments at the Experimental Farm Edgardia, in Botucatu, São Paulo State,
Brazil. In the past the forest fragment suffered disturbances due to the
selective exploitation of tree species and the use of part of the surface as
pasture. The objectives of this research were to evaluate the structure and the
dynamics of natural vegetation. Three phytosociological surveys (2006, 2010 and
2014) were carried out in a sampled area of one hectare. The most abundant
species were mapped in 2014,
in a sampling unit with two hectares. Individuals of 37
families and 110 species have been recorded. The oscillation of the basal area
observed through the forest inventories was due to the instability caused by
disturbances. Only two out of the seven most abundant species mapped showed
exponential diameter distribution. The unimodal distributions shown by the
other five species have suggested that the vegetation has been occupying the
most open spaces through regeneration in cycles. There was direct association
between the spatial distribution and the dispersion syndrome for five out of
the seven most abundant species. Three species have zoochoric dispersion,
showing that wild animals populations have accomplished their function in the
dispersion of seeds/fruit. The spatial distributions of four out of the seven
most abundant species have provided evidence of how the regeneration of natural
vegetation is being processed in this area.