The Atlantic Forest of South America: spatiotemporal dynamics of remaining vegetation and implications for conservation

Abstract

The Atlantic Forest in South America (AF) is one of the worlds most diverse and threatened biodiversity hotspots. We present a comprehensive spatiotemporal analysis of 34 years of AF landscape change between 1986-2020. We analyzed landscape metrics of forest vegetation only (FV), forest plus other natural vegetation (NV), and investigated the sensitivity of metrics to linear infrastructure. Currently, remnants comprise about 23% of FV and 36% of NV, and have decreased by 2.4% and 3.6% since 1986, respectively. Linear infrastructure negatively affected large fragments (>500,000 ha) by breaking them apart. Our findings suggest that AF protection legislation adopted in mid-2005 has taken effect: between 1986-2005, there was a loss of FV and NV (3% and 3.45%) and a decrease in the number of FV and NV fragments (8.6% and 8.3%). Between 2005-2020, there was a relative recovery of FV (1 Mha; 0.6%), slight loss of NV (0.25 Mha; 0.15%) and increase in the number of FV and NV fragments (12% and 9%). Still, 97% of the vegetation fragments are small (10 km). Our work highlights the importance of legislation and landscape dynamics analysis to help monitor and keep track of AF biodiversity conservation and restoration programs in the future. HighlightsO_LIThere is 23% forest and 36% natural vegetation cover remaining in the Atlantic Forest. C_LIO_LIBetween 1986-2020, native forest cover decreased by 2.4% and natural vegetation by 3.6%. C_LIO_LISince 2005, there has been a 1 Mha increase in forest area by small fragments (1 ha). C_LIO_LIRoads and railways reduced by 56%-89% fragment size, especially on large fragments. C_LIO_LIAlarmingly, 97% of fragments are small (<50 ha) and 60% are under edge effect (<90 m). C_LI