Connectivity dynamics of Araucaria forest and grassland surrounding Passo Fundo National Forest, southern Brazil

Changes in the structure of natural habitats surrounding Protected Areas interfere with biodiversity conservation measures. The goals of this research were to analyze the fragmentation and loss of vegetation in three landscape levels surrounding Passo Fundo National Forest, RS, Brazil, in 1986, 1997, and 2011, and to identify the degree of isolation/connectivity of these patches. These analyses were based on landscape metrics, in levels of classes and patches. The area occupied by vegetation increased for three landscape levels, from 1986 to 2011, accompanied by a reduction of the distances between remnants of the forest. Forest coverage was higher in the Protected Area in the other two levels of landscape. This scenario suggests a reduction of agricultural expansion in the region and an attenuation in the process of habitat loss and fragmentation. However, the current proportion (19%) of vegetation outside the Protected Area is still critical for many species.