The research unit DynaCom (Spatial community ecology in highly dynamic landscapes: from island biogeography to metaecosystems) is deeply rooted in ecological frameworks such as the equilibrium theory of island biogeography and metacommunity models. It investigates how spatial processes -such as colonization, extinction, and dispersal dynamics- structure the composition of ecological communities, biodiversity gradients, and associated ecosystem functions. DynaCom was planned for three phases with the overarching aim to develop a trait-based spatial community ecology, which allows understanding community composition, biodiversity and trophic interactions in spatially coupled systems across different scales. The final phase is serving as a synthesis phase enabling the work with the assembled data and furthering the model integration from previous phases.

Objectives

The overall goal of the research unit is split into three overarching objectives that were formulated at the start of DynaCom and that remain valid throughout the final synthesis phase:

• O1: Generate a multidimensional trait space for spatially structured food webs (meta-food webs), including the dimensions movement, interactions (including resource acquisition), and tolerance.
• O2: Extend the trait-based characterization of spatial communities to dynamic landscapes that experience strong stochastic disturbances.
• O3: Generalize this information to predict spatial patterns in biodiversity and food web structure in “island” systems ranging from the scale of local communities to regional island networks and the globe.

By integrating these goals, DynaCom is addressing a key gap in a rapidly evolving field which, despite substantial theoretical progress, has seen little coordinated empirical effort explicitly devoted to understanding the trait basis of spatial dynamics and its consequences for community organization. A marine-terrestrial interaction zone provided a unique environment for this purpose. The German Wadden Sea therefore served as the core field site, featuring strong rhythmic and stochastic dynamics in abiotic conditions, allowing an integrative analysis of marine and terrestrial food web compartments.

Project Structure

The research unit DynaCom is structured across three phases (DynaCom 1-3) and has now entered its third and final synthesis phase. During the first two phases (2019-2025), a large-scale field experiment in the back-barrier tidal flats of Spiekeroog was combined with extensive observational datasets from the East Frisian land-sea gradients and from island systems worldwide. These empirical studies were complemented by modelling approaches capturing both passive and active dispersal.
Building on the substantial empirical and theoretical advances achieved during these two phases, the third phase (2026-2028) brings together the complete datasets across organism groups with a metacommunity model capable of reproducing realistic community structure and biodiversity patterns along gradients. The integrated framework now enables the testing of concise hypotheses about the trait-based metacommunity ecology across terrestrial and marine environments.

Core hypotheses of DynaCom

In its final phase DynaCom will test three main hypotheses by unifying local, regional and global approaches across three main principles guiding the setup of the research group: (i) merging marine and terrestrial perspectives on spatial ecology in dynamic systems, (ii) enabling a large scale-transitive approach from local to global scales, and (iii) jointly fostering empirical and theoretical advances in the field.

•  H1: The land-sea interphase is characterized by transitions in traits, microbiomes and composition that shift dynamically in space depending on periodic (tides, seasons) and stochastic (droughts, storms) environmental changes.
• H2: Towards the stressful ends of the elevation gradient (i.e. at low elevation for terrestrial organisms and at high elevation for marine organisms), the dominant ecological processes in communities shift from predation (low-stress zones) to competition (moderate-stress zones) to environmental constraints (high-stress zones), whereas transition zones require symbiotic interactions.
• H3: Our understanding of community (dis-)assembly can be unified across gradients, metacommunities and island biogeography by a meta-gradient approach that allows gradients within patches as well as patches being aligned on gradients.