Abandoned pastures cannot spontaneously recover the attributes of old-growth savannas

1.Active restoration strategies have been recommended to recover Neotropical savannas in abandoned lands, but no studies have investigated the trajectories and speeds of spontaneous recovery for these systems. Research into the dynamics of degraded savannas is urgently needed to guide restoration decision-making.

2.We analysed the dynamics of secondary savannas in the Brazilian Cerrado by sampling 29 abandoned pastures (time since abandonment ranging from 3 to 25 years) and applying the space-for-time substitution method. We modelled the temporal changes in plant community attributes and estimated the time (years) required for these attributes to match those of two reference ecosystems (three replicates each), old-growth savanna and a forest-type savanna, which had encroached following fire suppression (encroached savanna). We also analysed the plant community composition of the study sites.

3.Our models showed that tree canopy cover, richness and density rapidly increased with ti...