O que nos dizem as libélulas, em Áreas de Preservação Permanente de córregos, sobre o Código Florestal Brasileiro?

Abstract

The riparian areas have high beta-diversity and are being suggested as priority areas for conservation. In Brazil, the riparian forests are protected under the form of Permanent Preservation Areas, however changes have been recently proposed to the Brazilian Forest Code providing for the reduction of required minimum width of riparian vegetation. This proposal generated a demand for information on the response of biodiversity compared to the width of the forest that borders water bodies. In this article, we asked if the community of Odonata disclosed the width of the forest, according to the current Forest Code. We used composition data of Odonata from 45 sampling sites in a highly fragmented landscape in the Brazilian Midwest to test the hypothesis that composition of the community of Odonata differs mainly in the extremes of environmental integrity in riparian forest classes evaluated. In order to test if there are differences in the values of the species richness among the three classes of width of riparian forests we applied the analysis of variance (ANOVA). Analysis of Similarity (ANOSIM) was used to determine the statistical differences between species composition and riparian forest classes. And to evaluate the ordenation patterns of the forest and riparian species of Odonata, was applied non-metric Multidimensional Scaling (NMDS) using the Jaccard index. In our study it was detected no relationship between species composition and richness, and width of riparian forests. Among potential factors that may be related to this result include: i) predominance of generalist species, ii) the influence of historical processes and biogeography and iii) the landscape setting. In addition, the use of rare species (exemplified here by singletons in the extremes of the range of riparian forest) seems to be indicators of potential environmental conditions, reporting different processes related to these areas.