Land-use change and intensification can be a threat to biodiversity of grassland habitats, including genetic diversity. This is especially true for areas where drastic changes in land use occurred in recent years. The Allgäu in Germany is known for a large proportion of grassland in its landscape. However, the sites often differ in their current management intensity and their land use history. While some sites have been used as grasslands for more than two centuries, other grasslands are much younger.
We assumed that landscape history and grassland management have a significant impact on genetic variation and therefore analysed the genetic variation of five typical grassland species using multiplexed ISSR (inter-simple sequence repeat) genotyping by sequencing (MIG-seq). We then related data on genetic variation with data on habitat quality, landscape structure and habitat age to identify possible drivers of genetic variation.
Our results indicated a high level of gene flow across the study area. Consequently, genetic differentiation among populations was correlated with geographic distance.
Genetic diversity clearly depended on habitat age but was not related to habitat conditions or landscape structure.
Synthesis and applications. Since ancient grasslands harbour genetically more diverse plant populations, land use history should be given more attention in conservation management.