Our research focusses on the origin, distribution, status and conservation of biodiversity at different spatial (landscape, habitat, population, genomics) and temporal (past, present) scales. We combine field ecology approaches (landscape, vegetation and population analyses) with molecular methods for recording genetic and epigenetics variation (SSR, AFLP, MSAP and MIG-Seq analyses) in order to investigate current research questions. A particular concern in this context is the linking of scientific research with nature conservation practice, in order to contribute to the long-term conservation of biological diversity.
Vegetation, restoration and population ecology
1 In this research field, we focus on the influence of land-use change on biodiversity in the cultural landscape of Central Europe, which manifests itself, among other things, in the loss and qualitative change of species-rich habitats and is associated with a decline in species diversity. We analyse the decline of habitats at the landscape level using geographic information systems (GIS) and investigate changes in vegetation composition due to intensification or abandonment of land use. We also analyse the effects of restoring species-rich grassland stands by sowing seed mixtures and monitor the sown stands using permanent observation plots. Another focus is the influence of land-use change on the structure of plant populations (e.g. population size and age) within habitats and the question of how this can be qualitatively and quantitatively recorded. Finally, we are looking at changes in alpine vegetation under the conditions of climate change.
Molecular biogeography, landscape genetics and clade differentiation
This research field focuses on analysing genetic variation as an essential component of biodiversity in the context of landscape history and structure. Of particular interest is the (post-)glacial recolonisation history of Central Europe and the phylogeography of native plant species. As changes in landscape structure in historical times also affect the genetic variation of plant species, this research field also deals with the influence of habitat age, fragmentation, isolation and land use on the genetic variation of plant species in the cultural landscape. The inclusion of historical plant material from natural history collections (herbarium material) and the use of material from DNA collections play a special role in these investigations. In a current project, we are analysing the temporal change in genetic variation in the cultural landscape by comparing past and present samples of the field weed Sherardia arvensis using next-generation sequencing (MIG-Seq). Material from our DNA collection, which now contains over 38,000 samples from 184 species, is used for this purpose. Because differentiation processes at the genetic level can ultimately lead to the emergence of new species, we are also investigating clade differentiation in the genera Hieracium and Taraxacum, which have undergone a particular adaptive radiation in the cultivated landscape.
2 Conservation and restoration genetics
3 This field of research focuses on the study of rare and endangered plant species and conservation measures to preserve the populations concerned. Of particular interest is the question of how the condition of in situ populations, the collection of seeds in the field, ex situ conservation in seed banks or conservation cultures and subsequent reintroduction affect the genetic variation and fitness of populations of endangered species. The natural genetic structure forms the basis for all subsequent conservation measures, with the aim of avoiding the negative effects of inbreeding and outbreeding. We also deal in detail with ex situ conservation, which plays an important role as a central nature conservation measure in various projects to establish seed genebanks (WEL, Bayern Arche, WIPS). The natural genetic structure of plant species does not necessarily correspond to the biogeographical and natural distribution units that are used as the basis for ex situ conservation in gene banks and the production of native seed, which is why we are currently conducting a research project that deals in detail with the population genetic basis for delimiting these regions of origin. In another project, we are also investigating which and how many populations or individuals need to be collected in order to map the genetic variation of species in ex situ conservation and how this affects genetic variation in the long term. The effects of supporting or reintroducing populations of endangered species are also of particular interest. The cultivation and propagation of plant material, taking into account conservation genetics aspects, can significantly increase the number of individuals, fitness and genetic variation of endangered species and contribute to the stabilisation of species. Various projects are therefore focussing on the question of whether the reintroduction of material from distant populations has a positive or negative effect. Crossbreeding experiments are being carried out for this purpose.
Ecological genetics and epigenetics
In this research field, we analyse the influence of environmental conditions and the life history traits of plants on the genetic and epigenetics structure of species and their populations. The focus is on the influence of natural environmental factors such as climate, soil moisture or disturbance along gradients in mountains, in bogs or along rivers and the influence of anthropogenic environmental factors such as mowing, grazing, herbicides or climbing in the cultivated landscape. In addition to genetic techniques, we are increasingly using epigenetic analysis methods. As the biological characteristics of plants also affect their genetic structure, we are investigating the significance of sexual and asexual (clonal) reproduction on genetic variation within and between populations as well. In addition to individual case studies, meta-studies play an important role. We continuously collect literature data on genetic variation and integrate them into a database for meta-analyses, which allow broader statements about the relationship between the life history traits of species and their genetic variation. Finally, as part of this research field, we are also investigating the question of whether species diversity and genetic diversity, as central elements of biodiversity, follow comparable mechanisms and how possible conflicts of objectives between different levels of biodiversity can be taken into account in practical nature conservation.
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Photos: 1, 2, 3, 4, Christoph Reisch