Synthesis area 2: Multitrophic interactions from local to regional scales

• Applicant: Professor Dr. Christoph Scherber
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 379417748

Salt marsh ecosystems are characterized by strong abiotic gradients (such as salinity and Inundation frequency). A multitude of previous studies has investigated invertebrate communities in salt marshes. However, These studies have often been restricted to either the above-or the belowground subsystem, or focused only on the terrestrial part of the gradient. Additionally, knowledge on feeding linkages among taxa has been limited. In synthesis subproject SYN2, data generated in the previous two phases of the DynaCom research unit (mainly from former subprojects 1-5 and 10) will be combined to test the stability and re-assembly of feeding linkages in salt marsh ecosystems following periodic (tides, seasons) and stochastic (droughts, storms) events (Hypothesis 1) and the response of multitrophic network attributes (size, structure) to abiotic gradients and stochastic disturbances (Hypothesis 2). Additionally, data collected within the DynaCom research unit will be combined with data from other, adjacent and similar salt marsh ecosystems (especially in the Netherlands) to test for generalizable patterns in multitrophic interaction network structure across space and time (Hypothesis 3). The subproject is structured into three work packages (WP): In WP1, an object-relational database on multitrophic interactions in salt marsh and intertidal ecosystems will be constructed, integrating an unprecedented range of data sources from eDNA metabarcoding of gut contents to amino acid, fatty acid profiles, plant DNA barcodes, fungal and bacterial DNA data from the project, literature sources and online databases. In WP2, state-of-the-art statistical analyses on multitrophic interactions will be done, using a combination of generalized linear mixed-effects models, graph-theoretical approaches and (piecewise) structural equation modeling. Finally, in WP3, additional data from other published sources and collaborating scientists from the Netherlands will be analyzed jointly with the DynaCom data to test for generalizability of multitrophic interaction structures. The subproject SYN2 will be tightly integrated into the other synthesis projects within Research Unit DynaCom, integrating data on plant community composition and traits (SYN1), molecular data (SYN3), model outputs from analyses across system boundaries (SYN4) and dispersal data useful for upscaling (SYN5). The subproject will thus be integral to achieve the overall goals described in the framework proposal of DynaCom, contributing to an enhanced understanding of the responses of multitrophic interactions to abiotic disturbances and periodicity in salt marsh ecosystems at marine-terrestrial boundaries.

• DFG Programme: Research Units
• Subproject of: FOR 2716: Spatial community ecology in highly dynamic landscapes: from island biogeography to metaecosystems [DynaCom]
• Co-Investigator: Professor Dr. Dirk Albach