Spatial-Temporal Analysis of the Forest Fragments Surrounding a Conservation Unit in the Southern Region of Brazil

Abstract

In recent years, anthropogenic actions have intensified forest fragmentation, causing several damages to the landscape's natural components, as the loss of biodiversity. This study aims to present an analysis of the forest fragments in a conservation unit located at southern of Brazil. The evaluation was carried out for the years 1998, 2008 and 2018, by using landscape metrics and classification of remote sensing imagery of the Landsat satellite. The following metrics were analyzed: area and edge, shape, core area, and aggregation. The results indicated an increase of 16.88% in the total area of vegetation, and the percentage of fragments increased from 16.16% to 18.89%. The number of fragments decreased, resulting in an increase of the mean area in 5.4 ha. The percentage of vegetation under border effect changed from 40.2% to 37.1%. In 1998, the average nearest neighbor distance was 155.4 m, and in 2018, 149.7 m. However, this distance is still classified as a high degree of isolation, which hinders the movement of organisms and the dispersion of species. Thus, all the analyzed metrics indicated a decrease in the fragmentation, except for the edge density metric, in which its increase of 1.86 pointed to a lower degree of conservation during the analyzed period. A study of this nature is important since it provides subsidies for future researches and can contribute to action strategies to be adopted in the management plan of the area.