Turnover rates of regenerated forests challenge restoration efforts in the Brazilian Atlantic forest

Abstract

Natural forest regeneration is a key component of global ecosystem restoration scenarios. Regenerated forests, however, may not persist and a better understanding of the drivers of forest persistence is critical to ensure the success of restoration efforts. We used 35 years of detailed land cover maps to quantify forest regeneration and study the drivers of regenerated forest persistence and longevity in the Brazilian Atlantic Forest, a restoration hotspot. We mapped over 4.47 Mha of native forest regenerated in the region between 1985 and 2019, of which, two thirds persisted until 2019 (3.1 Mha). However, mean age of ephemeral (i.e. cleared before 2019) forest regeneration was only 7.9 years, suggesting a rapid turnover of regrowing forests under certain conditions. Regenerated forests had greater longevity and probability of persistence in steeper slopes, close to rivers and existing forests, near permanent agriculture, and in areas with higher Gross Development Product and agricultural yield, but were less likely to persist in areas with higher rural-urban population ratios. Regeneration occurred predominantly in pasturelands and areas of shifting agriculture, but it was also less likely to persist within these dynamic landscapes. Specific public policies should stimulate forest regeneration in areas of consolidated agriculture, where forest permanence tends to be higher. The ephemerality of forest regeneration in the Brazilian Atlantic Forest highlights the importance of favorable conditions and policies that promote second-growth forest persistence in tropical regions. Conservation of regenerating forests is critical for meeting national and global restoration and climate mitigation goals.

Keywords

• reforestation
• second growth forests
• tropical forests
• land-use change
• land use dynamics
• Latin America