Avaliação da efetividade ecológica das áreas protegidas pela perspectiva do contexto espacial: implicações na Mata Atlântica

Abstract

Considering that the loss and fragmentation of habitats are the greatest threats to the maintenance of biodiversity on the planet, and the implementation of Protected Areas (PAs) is the largest conservation strategy used, the present work sought to systematize the assessment of the ecological effectiveness of these special units due to the consequences of the loss and fragmentation processes that is notable in the Atlantic Forest. Initially, in chapter 1, a bibliographic survey was made about the ecological mechanisms involved in the protected area environment relationship. It was verified that the reduction of habitats is crucial for the maintenance of the biodiversity found in the protected areas and it is the main consequence generated by the loss and fragmentation of habitats in the surroundings. These crucial habitats may be related to the effective ecosystem size for the species occurring in the PAs; to the presence of source landscapes of biodiversity; to the protection of edge effects of reserves; or to the ability to generate connectivity for the whole region. Landscape Ecology allowed us to generate efficient planning indicators for the evaluation of the ecological effectiveness of PAs from regional perspective. However, few methodologies explicitly consider these types of indicators. The second chapter presents a flexible methodological approach that allows the evaluation of the ecological effectiveness of protected areas through landscape metrics and identification of key landscapes in the surrounding region, using connectivity indexes based on graph theory and multiscale biological dispersal information of species. Through a case study presented in the Mosaic of the Extreme South of Bahia, it was evidenced that this protocol allowed to generate information quickly and useful to estimate the degree of threat of protected areas to the loss and the fragmentation of habitats in the surroundings. In addition, this protocol indicated, on a regional scale, a prioritization of landscapes that makes it possible to contribute to a more efficient management, focused on the objective of biodiversity conservation, by protected areas in the Atlantic Forest. We also note that the management of protected areas in this biome should be immersed in the concepts derived from Systematic Conservation Planning, highlighting the relationship of changes in land use around the ecological effectiveness of these special landscape units.