Biodiversity Exploratories
Biodiversity Exploratories are research units that investigate biological diversity in Germany. The Exploratorien are a joint project financed by the German Research Foundation (DFG Priority Program 1374 - Infrastructure). Three exploratories serve as an open research platform for scientists from all over Germany.
With the help of the stations, the relationships between the biodiversity of different taxa and levels, the role of land use and management for biodiversity and the role of biodiversity for ecosystem processes are examined.
The DFG Exploratories are the largest scientific project on functional biodiversity research in Germany to date. Over 330 scientists from various institutions and universities from all over Germany work in the various sub-projects.
Locations of the stations
So far there are three exploratories:
- Schorfheide-Chorin Biosphere Reserve in Brandenburg
- Hainich National Park and its surroundings in Thuringia
- Swabian Alb biosphere area in Baden-Württemberg
Research design
The investigations follow a strictly hierarchical structure.
Grid plots
There are a total of 1000 so-called grid plots: Each exploratory contains a large number of investigation areas, which differ in their investigation intensity. Since only grassland and forests are taken into account in the first project phase, a grid with a total of 1000 areas per exploratory was laid over selected landscape areas. In these, the number and frequency of plant species as well as land use types and intensity were documented. In addition, soil samples from each area are analyzed.
100 experiment plots (EPs)
After the first survey, a total of 100 of the grid plot areas (50 forest, 50 grassland per exploratory) were selected for a more intensive investigation. These represent the gradient of land use intensity from largely unused (e.g. EP in the landscape protection area at the Sternenberg / Swabian Alb) to heavily used ecosystems. These experiment plots are equipped with devices for measuring soil and air temperature as well as soil moisture and are of a size suitable for manipulation experiments.
On these experiment plots, the diversity of other groups such. B. of bees, ichneumonids and other Hymenoptera, Heteroptera, Diptera, Chrysomeliden, Curculioniden, Carabiden and xylobiontischen beetles examined. These groups of animals are regularly recorded using different trapping methods and types of traps (suction collectors, landing nets, cross window traps, photo-collectors and fumigation). In addition, the pollination systems for grassland plants and undergrowth are quantified by repeatedly collecting pollinating insects on individual plants.
Associated ecosystem processes are examined on these intensive study areas, e.g. B. biomass and growth of forests, annual net primary productivity in grasslands, soil respiration as well as carbon and nitrogen proportions of different parts of plants. In 16 of these 100 study areas (VIPs), very intensive studies on microorganism communities and mycorrhizal fungi are carried out with the help of molecular markers.
Experiments on the EPs
A number of so-called manipulation experiments take place on the experiment plots. Above all, they include manipulation of plant diversity, the exclusion of functional groups or the relocation of resources in order to determine the consequences for diversity and ecosystem function for the respective land use type and its intensity. In contrast to correlative connections from observations and monitoring, these experiments deal with the causal relationships.
Some tried and tested (established) experiments are:
- Seeding experiment in grassland to increase the limited number of seeds and thereby investigate the relationships between plant diversity and primary productivity
- Seeding experiment with tree species in order to test the limit of seed occurrence and the success of establishment as a function of the diversity and species identity of maternal trees
- Disturbance experiments to investigate the effects of disturbance intensity and frequency on the regenerative ability of different types of vegetation
- Enclosure experiment to exclude large herbivores and to determine their influence on tree establishment and diversity
- Litter displacement experiment to study changes in soil carbon and the destructive community
- Deadwood manipulation experiments on the ground and in the treetops to determine their importance for the xylobiontic community
- Small mammal exclusion experiment to determine their effects on arthropod diversity
- Bird and bat exclusion experiment with nets to determine their influence on arthropod diversity and the seed composition of plants
- Predator-prey manipulations z. B. Introduction of aphid colonies to assess their survival and that of associated predator communities
- Herbivory experiments to quantify the degree of herbivory on individual plants and to determine the plant fitness of sprayed and unsprayed plants
Sub-projects
In addition to the regular, systematic work of the core project, further sub-projects will cover various other taxa from 2008 onwards.
Publications
The project generates a large number of different data that lead to a wealth of publications. An almost complete list of publications can be found on the project page . Therefore only a small selection can be shown here.
PhD theses
- Steffen Boch (2011): Drivers of vascular plant and lichen diversity in Central European forests. Thesis, University of Bern
- Stephanie A. Socher (2011): Effects of land use on the diversity of grassland plants. Dissertation, University of Bern
- Manfred Türke (2011): Complicating a Complex Ecosystem Function: the Controversial Role of Gastropods in a Myrmecochorous Seed Dispersal Mutualism. Thesis, Friedrich Schiller University Jena
- Christiane Will (2011): Assessment of the functional diversity of soil microbial communities in the German Biodiversity Exploratories by metagenomics. Thesis, University of Goettingen
- Christiane Weiner (2016): Diversity and resource choice of flower-visiting insects in relation to pollen nutritional quality and land use. Thesis, TU Darmstadt
Diploma / Master / Bachelor theses
- Sofia Baur (June 2011): Food preference of the blue tit (Cyanistes caeruleus) before the start of the breeding season in the Swabian Alb. Bachelor thesis Institute for Experimental Ecology, supervision AG Kalko , University of Ulm .