Illuminating the ecosystem metabolism black box: Linking metabolism to food web dynamics (MetaBoxWeb)

• Applicants: Dr. Mario Brauns; Janine Rüegg, Ph.D.
• Subject Area: Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 574707126

Human activities significantly threaten biodiversity in freshwater ecosystems due to various stressors, including eutrophication, hydromorphological degradation, and the introduction of non-native species. These activities jeopardize biodiversity and may impair ecosystem functioning, impacting the goods and services that humans depend on. It is still uncertain whether changes in biodiversity lead to altered ecosystem functioning or if they occur simultaneously as a related phenomenon. This lack of understanding prevents effective management of streams and rivers, which currently focuses primarily on biodiversity instead of managing these ecosystems to sustain their functionality and the interconnected services they provide. Hence, a novel approach is needed that connects species identities and their functional role with whole-system organic matter cycling. With MetaBoxWeb, we will address structural-functional knowledge gaps by combining two previously separate disciplines, namely food web ecology and biogeochemistry. The proposed research will assemble the most comprehensive database of whole-stream metabolism and macroinvertebrate food webs, compiled through a systematic literature review, along with national and international monitoring data, as well as unpublished information from our network of collaborators. On its basis, we quantify how diversity affects ecosystem function in streams and whether and how macroinvertebrate diversity and energy flow can be predicted from whole-stream primary production and respiration. Moreover, we aim to establish and apply functional indicators that link biodiversity metrics to ecosystem functioning via organismal productivity. Ultimately, our findings will contribute to developing better strategies for maintaining ecosystem function and the valuable services freshwater ecosystems provide.

• DFG Programme: Research Grants