Multi‐decadal woodland recovery after land abandonment: environmental constraints on passive rewilding in Mediterranean landscapes

Introduction Across the Mediterranean Basin, land abandonment has opened large areas to passive rewilding, raising questions about the pace and variability of secondary succession in these landscapes and how ecological and abiotic gradients mediate vegetation recovery in post‐agricultural landscapes. Objectives This study aims to quantify long‐term successional change under passive rewilding and identify the environmental constraints shaping recovery pathways and timelines. Methods Using the Baixo Sabor region in northeastern Portugal as a case study, we examined woody vegetation recovery over a 75‐year chronosequence following farmland abandonment. Data from 118 field plots, analyzed using Generalized Additive Models, were used to model vegetation structure, species composition, and regeneration as functions of time since abandonment and interacting environmental factors. Results We found that under passive rewilding, transitions toward late‐successional woodland structure may require at least 60–80 years, particularly in dry, exposed sites. Regeneration was faster in north‐facing, moister plots near remnant forests, favoring species such as Quercus rotundifolia , while early‐successional shrub dominance persisted in harsher areas far from historical forest patches. Environmental filters including solar radiation, slope, and historical forest connectivity strongly modulated successional pathways. Conclusions These findings show that the pace of passive rewilding is strongly context‐dependent and that, in dry and exposed settings, transitions toward late‐successional woodland structure may exceed 75 years.