INFLUêNCIA DA TOPOGRAFIA E DA ABERTURA DO DOSSEL NA ESTRUTURA DO COMPONENTE HERBáCEO-ARBUSTIVO EM DOIS FRAGMENTOS FLORESTAIS NA PLANíCIE DE INUNDA??O DO ALTO RIO PARANá

摘要

Secondary forests have enlarged significantly throughout the years. Due to the importance that this kind of forest has taken on regarding plans for restoration and conservation, a wider understanding of its organization and functioning, considering the different forms of life is necessary. Aiming at comparing the composition and structure of the herb-shrub component between two forest areas at different stages of recovery (RFID–forest remnant and FLT– 57-year old forest), as well as the relative influence of the topography and canopy opening on the organization of the community, vegetation and environmental data were collected on 24 contiguous plots in each area. Moran’s I correlograms and partial Mantel tests were used to test for correlations between community data and environmental variables. To examine differences between sample areas, Student’s t -tests were applied. The lianas proved to be spatially structured in both environments, with a similar trend observed in the mean average. In RFID, average quota distances were positively correlated with the distances of tree density and total richness matrices and negatively correlated with the distance matrix density of herbaceous plants. In FLT, significant correlations were observed only between the distances of the tree density matrix and those of maximum difference of data and between distances of elevation data and those of total wealth array. By comparing the two areas, significant differences were not obtained only to the shrub components and to canopy opening. The structure of the herbaceous shrub component was associated with topographic characteristics, suggesting a strong influence of the flooding regime, whereas the canopy opening seemed not to exert an obvious influence on the same.