Romans Shape Today's Vegetation and Soils: Two Millennia of Land-Use Legacy Dynamics in Mediterranean Grasslands

Archeological investigations in one of the most species-rich French Mediterranean dry grasslands (La Crau, Southern France) revealed a dense network of ancient sheep corrals dating from Roman to modern times. By analyzing soil chemistry and vegetation across abandonment dates spanning two millennia, we bring to light a persisting signature of Roman, eighteenth century and modern corrals on present-day ecosystems. Community composition and species-richness reflect time after abandonment of sheep stables and are linked to long-term persistence of eutrophication from historical sheep concentrations. Our data highlight changes in vegetation that persist two millennia after human impacts ceased. Small-scale pastoral legacies from Roman times continue to have significant impacts on present-day herbaceous plant communities. Our findings point to a need for greater consideration of persisting eutrophication in dry grasslands and of the conservation value of these long-term legacies.

Automated summary

Archaeological investigations in the species-rich French Mediterranean dry grasslands revealed a dense network of ancient sheep corrals dating from Roman to modern times, showing a persistent impact on present-day ecosystems. The study highlighted changes in vegetation that persist two millennia after human impacts ceased, indicating the significant impacts of Roman pastoral legacies on present-day herbaceous plant communities. This calls for greater consideration of persisting eutrophication and the conservation value of long-term legacies in dry grasslands.