Restoration of calcareous grasslands by natural recolonization after forest clearing and its impact on the genetic variation of three common herb species

Abstract Species-rich calcareous grasslands in Europe strongly declined during the twentieth century due to drastic land use changes. Many were converted into more productive pastures or are covered by shrubs forests today, since they overgrown after abandonment afforested. Restoration of shrub forest clearing and subsequent recolonization grassland species from adjacent is, therefore, an important conservation approach. Restored populations may, however, differ their source genetic diversity differentiation potential founder bottleneck effects. In our study we analyzed, impact restoration natural on variation three common ( Agrimonia eupatoria , Campanula rotundifolia Knautia arvensis ) without a contribution persistent seed bank, South Western Germany. We used molecular markers AFLPs (Amplified fragment length polymorphisms) compare within between spontaneously recovered subpopulations with historically old, at eight sites. parts have been re-established 1990s. Molecular revealed broadly similar levels restored species. Only A. exhibited slightly higher subpopulations, which may be explained dispersal hooky fruits Genetic was not significant, indicating strong gene flow subpopulations. Our underlines, that is efficient method re-establish genetically variable comparable sources.