Landscape fragmentation around ferruginous caves of the iron quadrangle, Minas Gerais, Brazil

Abstract

The aim of this article is to analyse the landscape fragmentation around ferruginous caves in the Iron Quadrangle (Minas Gerais, Brazil) and the conditions of environmental stability of the caves inserted in vegetal remnants under edge effects caused by anthropic activities. The methodology applied involved the implementation of three different landscape metrics to stablish the total area of patches, the area of the patches under edge effects (core area), and the distance from the nearest neighbour. The measurements were calculated considering classes of vegetal coverage (herbaceous, shrub, and arboreal vegetation) and then processed and combined by using map algebra to obtain the fragmentation degree, which was classified into three classes: high, moderate, and low. Results reveal that 62.88% of the vegetation coverage of the study area presents a low degree of fragmentation. Among the caves under edge effects, 15% obtained negative indices of environmental stability. Although most of the analysed caves are located in areas with a low degree of fragmentation, the proximity of anthropized areas and the risk they represent for the speleological heritage reinforce the need to create strategies focused on the conservation of the caves.