DynaCom

Spatial community ecology in highly dynamic landscapes: from island biogeography to metaecosystems

The Wadden Sea and the adjacent salt marshes are characterised by rapidly changing environmental influences. Here, dynamic processes take place within ecological communities over short periods of time. These include (i) regional processes such as dispersal and colonisation and (ii) local organism interactions such as competition, mutualism and trophic interactions. Theoretical models such as the equilibrium theory of island biogeography and the concept of metacommunity can explain some of these dynamic processes. The Wadden Sea and the neighbouring salt marshes offer the opportunity to observe these processes in a relatively short time frame.

The project on the island of Spiekeroog, funded by the German Research Foundation (DFG), includes studies in the salt marshes of the Wadden Sea National Park and on several artificial islands. These islands have already proven their worth in previous projects for the empirical investigation of highly dynamic systems.

Project approach

The "DynaCom" research group is divided into several sub-projects, each investigating a different component of the marine and terrestrial food webs (primary producers, primary consumers, predators). In this project, various scientists from the universities of Oldenburg, Göttingen and Munich as well as from iDiv (Halle-Jena-Leipzig), the Senckenberg Research Institute in Frankfurt and the Museum Koenig in Bonn are working together in co-operation with the Lower Saxony Wadden Sea National Park. The results of the sub-projects will ultimately be combined to enable a high degree of generalisation across different types of organisms.

At Museum Koenig, the terrestrial biocoenosis of the salt marshes on the island of Spiekeroog is being analysed in sub-project 3. Spatial and temporal distribution patterns as well as trophic interactions of above- and below-ground invertebrates are analysed. Firstly, ground beetles from different zones of the salt marshes will be captured in order to collect regurgitated samples. The samples are then analysed using molecular methods (DNA metabarcoding) in order to decipher the ground beetles' food spectrum. These analyses can provide information on the origin of the resources (marine vs. terrestrial, primary vs. secondary producers). Finally, the activity of the invertebrates in relation to the constantly changing environmental influences is also documented by camera monitoring.

Trait-based model for ecosystem dynamics

The DFG Research Unit "DynaCom" investigates the significance of characteristics of terrestrial and marine organisms for regional and local dynamic processes in ecosystems. A comprehensive analysis of food web structures in a spatial context enables statements to be made about the dispersal, resource use and behaviour of different organism species in the event of sudden environmental changes. Ultimately, the experimentally collected data can be used to develop a feature-based model that enables the transfer of dynamic processes from local to global scales.