Glacial Meltwater Increases the Dependence on Marine Subsidies of Fish in Freshwater Ecosystems ...

• Main Authors: Saboret, Grégoire, Moccetti, Coralie, Takatsu, Kunio, Janssen, David J., Matthews, Blake, Brodersen, Jakob, Schubert, Carsten J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2024
• Subjects: amino acid stable isotopes; arctic char; glaciers; global warming; marine-derived nutrients; meta-ecosystem; subsidies; salmon migration; trophic position; Arctic; Greenland; glacier; Global warming
• Online Access: https://dx.doi.org/10.3929/ethz-b-000681554; http://hdl.handle.net/20.500.11850/681554

In a warming world, the input of glacier meltwater to inland water ecosystems is predicted to change, potentially affecting their productivity. Meta-ecosystem theory, which posits that the nutrient availability in the recipient ecosystem can determine the extent of cross-ecosystem boundary utilization, can be useful for studying landscape-scale influences of glacier meltwater on inland waters. Here, we investigate how the input of glacier meltwater in a river system in Southern Greenland influences the utilization of marine subsidies in freshwater fish. Our study system comprised four sites, with controls for glacial meltwater and marine subsidies, harboring a partially migrating population of arctic char, meaning that some individuals migrate to the ocean and others remain in freshwaters, and two fully resident populations as a freshwater reference. We assessed the incorporation of marine carbon in freshwater resident char using both bulk and amino acid stable isotope analysis of muscle tissue. In the ... : Ecosystems ...