Restoration of grasslands on ex-arable land using regional and commercial seed mixtures and spontaneous succession: Successional trajectories and changes in species richness

Grasslands restored in the three different ways converged in their species composition and developed generally towards reference grasslands. Considering the number of target grassland species, sowing of regional seed mixtures was the most successful, especially in the beginning, but processes of spontaneous succession led virtually to the same number of target species, even at sites re-grassed with commercial seed mixtures, but more slowly. Development of sites re-grassed spontaneously and by sowing commercial seed mixtures led to the establishment of more mesic vegetation (Arrhenatherion) than when using the regional seed mixture, which was predominantly composed of species typical of dry grasslands (Bromion). Thus, restoration of the most valuable dry grasslands should preferably be based on using properly designed regional seed mixtures.